Moon Exploration from "apollo" Magnetic and Gravity Field Data

NASA Astrophysics Data System (ADS)

Kharitonov, Andrey

Recently, the great value is given to various researches of the Moon, as nearest nature satellite of the Earth, because there is preparation for forthcoming starts on the Moon of the American, European, Russian, Chinese, Indian new Orbiters and Landers. Designing of International Lu-nar bases is planned also. Therefore, in the near future the series of the questions connected with placing of International Lunar bases which coordinates substantially should to be connected with heterogeneity of the internal structure of the Moon can become especially interesting. If in the Moon it will be possible to find large congestions of water ice and those chemical elements which stocks in the Earth are limited this area of the Moon can become perspective for Inter-national Lunar bases. To solve a question of research of the deep structure of the Moon in the locations of International Lunar bases, competently, without excessive expenses for start new various under the form of the Lunar orbit of automatic space vehicles (polar, equatorial, inclined to the rotation axis) and their altitude of flight, which also not always were connected with investigation programs of measured fields (video observation, radio-frequency sounding, mag-netic, gravity), is possible if already from the available information of space vehicles APOLLO, SMART1, KAGUYA, LCROSS, LRO, CHANDRAYAAN-1, CHANG'E-1 it will be possible to analyse simultaneously some various fields, at different altitudes of measuring over the surface (20-300 km) of the Moon. The experimental data of the radial component magnetic field and gravity field the Moon measured at different altitudes, in its equatorial part have been analysed for the research of the deep structure of the Moon. This data has been received as a result of start of space vehicles -APOLLO-15 and APOLLO-16 (USA), and also the Russian space vehicles "LUNOHOD". Authors had been used the data of a magnetic field of the Moon at flight altitude 160, 100, 75, 30, 0 km. All orbits of APOLLO-15 space vehicle at flight altitude from 160 to 75 km have been executed near to Moon equator, in the latitude direction round the Moon, in a strip in width about 250 km, in the range from 15 degrees of the northern latitude to 15 degrees of the southern latitude. For calculations of deep parameters according to the Moon magnetic field as much as possible high flight altitude (h=160 km), average flight altitude (h=100 km), the minimum flight altitude (h=75 km) APOLLO-15 space vehicle have been used. The data about the Moon magnetic field at 30 km flight altitude has been pre-sented by one pass APOLLO-16. The depths of several magnetic and density borders into the Moon which allow to make some assumptions of possible structure of rocks of the Moon were defined. The activity is executed at support of Russian Foundation of Basic Researh, grant 10-05-00343-a.

Reflection imaging of the Moon's interior using deep-moonquake seismic interferometry

NASA Astrophysics Data System (ADS)

Nishitsuji, Yohei; Rowe, C. A.; Wapenaar, Kees; Draganov, Deyan

2016-04-01

The internal structure of the Moon has been investigated over many years using a variety of seismic methods, such as travel time analysis, receiver functions, and tomography. Here we propose to apply body-wave seismic interferometry to deep moonquakes in order to retrieve zero-offset reflection responses (and thus images) beneath the Apollo stations on the nearside of the Moon from virtual sources colocated with the stations. This method is called deep-moonquake seismic interferometry (DMSI). Our results show a laterally coherent acoustic boundary around 50 km depth beneath all four Apollo stations. We interpret this boundary as the lunar seismic Moho. This depth agrees with Japan Aerospace Exploration Agency's (JAXA) SELenological and Engineering Explorer (SELENE) result and previous travel time analysis at the Apollo 12/14 sites. The deeper part of the image we obtain from DMSI shows laterally incoherent structures. Such lateral inhomogeneity we interpret as representing a zone characterized by strong scattering and constant apparent seismic velocity at our resolution scale (0.2-2.0 Hz).

Ancient Multiring Basins on the Moon Revealed by Clementine Laser Altimetry

NASA Astrophysics Data System (ADS)

Spudis, Paul D.; Reisse, Robert A.; Gillis, Jeffrey J.

1994-12-01

Analysis of laser altimetry data from Clementine has confirmed and extended our knowledge of nearly obliterated multiring basins on the moon. These basins were formed during the early bombardment phase of lunar history, have been filled to varying degrees by mare lavas and regional ejecta blankets, and have been degraded by the superposition of large impact craters. The Mendel-Rydberg Basin, a degraded three-ring feature over 600 kilometers in diameter on the lunar western limb, is about 6 kilometers deep from rim to floor, only slightly less deep than the nearby younger and much better preserved Orientale Basin (8 kilometers deep). The South Pole-Aitken Basin, the oldest discernible impact feature on the moon, is revealed as a basin 2500 kilometers in diameter with an average depth of more than 13 kilometers, rim crest to floor. This feature is the largest, deepest impact crater yet discovered in the solar system. Several additional depressions seen in the data may represent previously unmapped ancient impact basins.

Lunar and Planetary Science XXXV: Lunar Geophysics: Rockin' and a-Reelin'

NASA Technical Reports Server (NTRS)

2004-01-01

This document contained the following topics: The Influence of Tidal, Despinning, and Magma Ocean Cooling Stresses on the Magnitude and Orientation of the Moon#s Early Global Stress Field; New Approach to Development of Moon Rotation Theory; Lunar Core and Tides; Lunar Interior Studies Using Lunar Prospector Line-of-Sight Acceleration Data; A First Crustal Thickness Map of the Moon with Apollo Seismic Data; New Events Discovered in the Apollo Lunar Seismic Data; More Far-Side Deep Moonquake Nests Discovered; and Manifestation of Gas-Dust Streams from Double Stars on Lunar Seismicity.

Microbial habitability of Europa sustained by radioactive sources.

PubMed

Altair, Thiago; de Avellar, Marcio G B; Rodrigues, Fabio; Galante, Douglas

2018-01-10

There is an increasing interest in the icy moons of the Solar System due to their potential habitability and as targets for future exploratory missions, which include astrobiological goals. Several studies have reported new results describing the details of these moons' geological settings; however, there is still a lack of information regarding the deep subsurface environment of the moons. The purpose of this article is to evaluate the microbial habitability of Europa constrained by terrestrial analogue environments and sustained by radioactive energy provided by natural unstable isotopes. The geological scenarios are based on known deep environments on Earth, and the bacterial ecosystem is based on a sulfate-reducing bacterial ecosystem found 2.8 km below the surface in a basin in South Africa. The results show the possibility of maintaining the modeled ecosystem based on the proposed scenarios and provides directions for future models and exploration missions for a more complete evaluation of the habitability of Europa and of icy moons in general.

Mass Wasting on the Moon: Implications for Seismicity

NASA Technical Reports Server (NTRS)

Weber, Renee; Nahm, Amanda; Schmerr, Nick; Yanites, Brian

2016-01-01

Seismicity estimates play an important role in creating regional geological characterizations, which are useful for understanding a planet's formation and evolution, and are of key importance to site selection for landed missions. Here we investigate the regional effects of seismicity in planetary environments with the goal of determining whether such surface features on the Moon, could be triggered by fault motion.

Mass Wasting on the Moon: Implications for Seismicity

NASA Technical Reports Server (NTRS)

Weber, R. C.; Nahm, A. L.; Yanites, B.; Schmerr, N.

2016-01-01

Introduction: Seismicity estimates play an important role in creating regional geological characterizations, which are useful for understanding a planet's formation and evolution, and of key importance to site selection for landed missions. Here we investigate the regional effects of lunar seismicity with the goal of determining whether surface features such as landslides and boulder trails on the Moon are triggered by fault motion.

Constraining the Material that Formed the Moon: The Origin of Lunar V, CR, and MN Depletions

NASA Technical Reports Server (NTRS)

Chabot, N. L.; Agee, C. B.

2002-01-01

The mantles of the Earth and Moon are similarly depleted in V, Cr, and Mn relative to chondritic values. Core formation deep within the Earth was suggested by as the origin of the depletions. Following Earth's core formation, the Moon was proposed to have inherited its mantle from the depleted mantle of the Earth by a giant impact event. This theory implied the Moon was primarily composed of material from the Earth's mantle. Recent systematic metal-silicate experiments of V, Cr, and Mn evaluated the behavior of these elements during different core formation scenarios. The study found that the V, Cr, and Mn depletions in the Earth could indeed be explained by core formation. The conditions of core formation necessary to deplete V, Cr, and Mn in the Earth's mantle were consistent with the deep magma ocean proposed to account for the Earth's mantle abundances of Ni and Co. Using the parameterizations of for the metal-silicate partition coefficients (D) of V, Cr, and Mn, we investigate here the conditions needed to match the depletions in the silicate Moon and determine if such conditions could have been present on the giant impactor.

The clementine bistatic radar experiment: Evidence for ice on the moon

USGS Publications Warehouse

Spudis, P.D.; Nozette, S.; Lichtenberg, C.; Bonner, R.; Ort, W.; Malaret, E.; Robinson, M.; Shoemaker, E.

1998-01-01

Ice deposits, derived from comets and water-bearing meteorites hitting the Moon over geological times, have long been postulated to exist in dark areas near the poles of the Moon. The characteristics of radio waves beamed from the Clementine spacecraft into the polar areas, reflected from the Moon's surface, and received on the large dish antennas of the Deep Space Network here on Earth show that roughly the volume of a small lake (???0.9-1.8 km3) of water ice makes up part of the Moon's surface layer near the south pole. The discovery of ice near the lunar south pole has important ramifications for a permanent return to the Moon. These deposits could be used to manufacture rocket propellant and to support human life on the Moon. ?? 1998 MAHK Hayka/Interperiodica Publishing.

High stress shallow moonquakes - Evidence for an initially totally molten moon

NASA Technical Reports Server (NTRS)

Binder, A. B.; Oberst, J.

1985-01-01

Thermoelastic stress calculations show that if the moon was initially molten only in the outer few hundred kilometers, as in the magma ocean model of the moon, the highlands crust should be aseismic. In contrast, if the moon was initially totally molten, high stress (1 to more than about 3 kbar), shallow (0 to about 6 km deep), compressional moonquakes should be occurring in the highlands crust. Calculations of the minimum stress drops made for the 28 observed shallow moonquakes suggest that 3 of them probably have stress drops in the kbar range. Thus, these very limited seismic data are consistent with the model that the moon was initially totally molten.

Low-Cost Planetary Missions Enabled by the Deep Space Gateway

NASA Astrophysics Data System (ADS)

Berinstain, A.; Richards, R. D.

2018-02-01

The authors will present options for discussion among participants of how low-cost lunar and planetary missions using the Moon Express family of spacecraft can be enabled by the presence of the Deep Space Gateway.

Evaluating Space Weather Architecture Options to Support Human Deep Space Exploration of the Moon and Mars

NASA Astrophysics Data System (ADS)

Parker, L.; Minow, J.; Pulkkinen, A.; Fry, D.; Semones, E.; Allen, J.; St Cyr, C.; Mertens, C.; Jun, I.; Onsager, T.; Hock, R.

2018-02-01

NASA's Engineering and Space Center (NESC) is conducting an independent technical assessment of space environment monitoring and forecasting architecture options to support human and robotic deep space exploration.

Deep electromagnetic sounding of the moon with Lunokhod 2 data

NASA Technical Reports Server (NTRS)

Vanyan, L. L.; Yegorov, I. V.; Faynberg, E. B.

1977-01-01

Results of electromagnetic sounding distinguished an outer high resistance shell about 200 km thick in the moon's structure. A preliminary petrological interpretation of the moon's layers indicated their origin as a consequence of differentiation of the initial peridotite material. Upon melting, 20% to 40% of the material melts and is removed to form a high resistance basaltic shell underlain by a layer of spinal peridotites enriched in divalent iron oxides and having a reduced resistance.

Electromagnetic sounding of the moon using Apollo 16 and Lunokhod 2 surface magnetometer observations /preliminary results/

NASA Technical Reports Server (NTRS)

Vanian, L. L.; Vnutchokova, T. A.; Fainberg, E. B.; Eroschenko, E. A.; Dyal, P.; Parkin, C. W.; Daily, W. D.

1977-01-01

A technique of deep electromagnetic sounding of the moon using simultaneous magnetic-field measurements at two lunar surface sites is described. The method, used with the assumption that deep electrical conductivity is a function only of lunar radius, has the advantage of allowing calculation of the external driving field from two surface-site measurements only and therefore does not require data from a lunar orbiting satellite. A transient-response calculation is presented for the example of a magnetic-field discontinuity, measured simultaneously by Apollo 16 and Lunokhod 2 surface magnetometers.

Electromagnetic Sounding of the Moon Using Apollo 16 and Lunokhod 2 Surface Magnetometer Observations (Preliminary Results)

NASA Technical Reports Server (NTRS)

Vanyan, L. L.; Vnutchokova, T. A.; Fainberg, E. B.; Eroschenko, E. A.; Dyal, P.; Parkin, C. W.; Parkin, C. W.

1977-01-01

A new technique of deep electromagnetic sounding of the Moon using simultaneous magnetic field measurements at two lunar surface sites is described. The method, used with the assumption that deep electrical conductivity is a function only of lunar radius, has the advantage of allowing calculation of the external driving field from two surface site measurements only, and therefore does not require data from a lunar orbiting satellite. A transient response calculation is presented for the example of a magnetic field discontinuity of February 13, 1973, measured simultaneously by Apollo 16 and Lunokhod 2 surface magnetometers.

Deep Mapping the Biome: The Biology of Place in Don Gayton's "The Wheatgrass Mechanism" and John Janovy Jr.'s "Dunwoody Pond"

ERIC Educational Resources Information Center

Maher, Susan Naramore

2005-01-01

The term "deep map" is the invention of writer William Least Heat-Moon, whose extended essay "PrairyErth (a deep map)" has given definition to this form. Deep-map writing is marked by its intertextual, interdisciplinary, and multivocal nature. It is also self-consciously cartographic, presenting maps, following maps, and redrawing maps. Deep…

Scientific analogs and the development of human mission architectures for the Moon, deep space and Mars

NASA Astrophysics Data System (ADS)

Lim, D. S. S.; Abercromby, A.; Beaton, K.; Brady, A. L.; Cardman, Z.; Chappell, S.; Cockell, C. S.; Cohen, B. A.; Cohen, T.; Deans, M.; Deliz, I.; Downs, M.; Elphic, R. C.; Hamilton, J. C.; Heldmann, J.; Hillenius, S.; Hoffman, J.; Hughes, S. S.; Kobs-Nawotniak, S. E.; Lees, D. S.; Marquez, J.; Miller, M.; Milovsoroff, C.; Payler, S.; Sehlke, A.; Squyres, S. W.

2016-12-01

Analogs are destinations on Earth that allow researchers to approximate operational and/or physical conditions on other planetary bodies and within deep space. Over the past decade, our team has been conducting geobiological field science studies under simulated deep space and Mars mission conditions. Each of these missions integrate scientific and operational research with the goal to identify concepts of operations (ConOps) and capabilities that will enable and enhance scientific return during human and human-robotic missions to the Moon, into deep space and on Mars. Working under these simulated mission conditions presents a number of unique challenges that are not encountered during typical scientific field expeditions. However, there are significant benefits to this working model from the perspective of the human space flight and scientific operations research community. Specifically, by applying human (and human-robotic) mission architectures to real field science endeavors, we create a unique operational litmus test for those ConOps and capabilities that have otherwise been vetted under circumstances that did not necessarily demand scientific data return meeting the rigors of peer-review standards. The presentation will give an overview of our team's recent analog research, with a focus on the scientific operations research. The intent is to encourage collaborative dialog with a broader set of analog research community members with an eye towards future scientific field endeavors that will have a significant impact on how we design human and human-robotic missions to the Moon, into deep space and to Mars.

Lunar environment and design of China's first moon rover Yutu

NASA Astrophysics Data System (ADS)

Jianhui, Wu

China launched the Chang'e-3 lunar probe with the country's first moon rover aboard on Dec.14, marking a significant step toward deep space exploration.Lunar environment and environmental tests of typical lunar survyeors are discussed in this papaer.According to the needs of China's lunar exploration project,environmental impact of moon rovers and Yutu design ideas are studied.Through the research, temperature control device, micro-gravity environment design ,dust and other equipment devices used on Yutu all meet the mission requirements.

Deep Space Gateway "Recycler" Mission

NASA Astrophysics Data System (ADS)

Graham, L.; Fries, M.; Hamilton, J.; Landis, R.; John, K.; O'Hara, W.

2018-02-01

Use of the Deep Space Gateway provides a hub for a reusable planetary sample return vehicle for missions to gather star dust as well as samples from various parts of the solar system including main belt asteroids, near-Earth asteroids, and Mars moon.

Mass Wasting In Planetary Environments: Implications For Seismicity

NASA Technical Reports Server (NTRS)

Weber, R. C.; Nahm, A. L.; Schmerr, N.

2015-01-01

On Earth, mass wasting events such as rock falls and landslides are well known conse-quences of seismic activity. Through a variety of re-mote sensing techniques, tectonic faults have been pos-itively identified on all four of the inner planets, Earth's Moon, several outer planet satellites, and aster-oids. High-resolution imaging has furthermore ena-bled positive identification of mass wasting events on many of these bodies. On Mars, it has been suggested that fallen boulders may be indicative of pale-omarsquakes. On the Moon, meteor impacts and moonquakes have likewise been suggested as potential triggering mechanisms for mass wasting. Indeed, we know from the Apollo era that the Moon experienc-es a wide variety of seismicity. Seismicity estimates play an important role in creat-ing regional geological characterizations, which are useful not only for understanding a planet's formation and evolution, but also of key importance to site selec-tion for landed missions. Here we investigate the re-gional effects of seismicity in planetary environments with the goal of determining whether surface features such as landslides and boulder trails on the Moon, Mars, and Mercury could be triggered by fault motion. We attempt to quantify the amount of near-source ground shaking necessary to mobilize the mate-rial observed in various instances of mass wasting.

A World of Hurt

NASA Technical Reports Server (NTRS)

2005-01-01

The most detailed images ever taken of Saturn's moon Mimas show it to be one of the most heavily cratered Saturnian moons, with little if any evidence for internal activity. Mimas has been so heavily cratered that new impacts can only overprint or even completely obliterate other older craters. Mimas is 397 kilometers or (247 miles) across.

The moon displays an unexpected array of crater shapes. The highest crater walls tower 6 kilometers (4 miles) above the floors and show signs of material sliding down slope. Indeed, many of the large craters -- more than 15 kilometers (10 miles) in diameter -- appear to be filled in with rough-surfaced material, likely the result of landslides triggered by subsequent impacts elsewhere on Mimas' surface. Some of these deposits have craters superimposed on them, demonstrating that the landslides themselves may be quite old.

Grooves, some of which are over a kilometer deep, cut across the surface for more than 100 kilometers (63 miles). These are some of the only indications that there might have once been internal activity under this ancient, battered surface.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

Recent activity in the moon; Proceedings of the Special Symposium, Houston, Tex., March 16, 1976

NASA Technical Reports Server (NTRS)

Runcorn, S. K.; Oreilly, W.; Srnka, L. J.

1977-01-01

The papers review evidence for recent activity within the moon as manifested by lunar grid system, transient phenomena, moonquakes, and episodic emissions of radiogenic gases. Topics include a survey of lunar transient phenomena, possible causes of such phenomena, evidence that high-frequency seismic events may be shallow moonquakes, lunar seismicity and tectonics, a hypothesis on the nature of sites of lunar gas venting, and a search for sporadic gas emissions from the moon. Other contributions discuss the release of radiogenic argon-40 from the moon, radon-222 emission as an indicator of current activity on the moon, upper limits to gas emission from sites of lunar transient phenomena, physical processes that could produce transient changes on the lunar surface, critical-velocity gas-plasma interaction as a mechanism for lunar transient phenomena, and tidal triggering of moonquakes, transient phenomena, and radiogenic-gas emissions.

The legal regime for moon resource utilization, with particular emphasis on environmental protection, and comparable solutions adopted for deep seabed activities

NASA Astrophysics Data System (ADS)

Viikari, L.

This paper will examine the resource utilization regime as established by the body of international space law and by the 1979 Moon Treaty in particular, as well as the current problems pertaining to it. A particular area of interest is environmental protection vis-à-vis resource utilization. A potential source of fruitful analogy is provided by the deep seabed mineral utilization regime, as established by the 1982 United Nations Convention on the Law of the Sea, the 1994 New York Agreement amending it, and the recent 2000 Mining Code as the first part of more detailed regulations that will eventually govern exploration for and exploitation of all deep seabed minerals. Such comparison seems advantageous, because several developments in the field of using the space environment are showing obvious similarities with previous developments in the law of the sea regarding deep seabed resource management. The Moon and the deep seabed (and their natural resources) are also the only environs explicitly proclaimed as the common heritage of mankind. On the other hand, both domains are increasingly affected by commercializat ion and privatization, too. A recent new (legally non-binding) instrument for space activities is the 1996 Declaration on International Cooperation in the Exploration and Use of Outer Space for the Benefit and in the Interests of All States, Taking into Particular Account the Needs of Developing Countries. It attempts at an important compromise regarding the Common Heritage provision, offering a means to share benefits while recognizing market principles. These principles very much resemble the previous solutions adopted by the 1994 New York Agreement for the deep seabed. The paper attempts to reflect in particular upon the experience available from such developments.

Further Constraints and Uncertainties on the Deep Seismic Structure of the Moon

NASA Technical Reports Server (NTRS)

Lin, Pei-Ying Patty; Weber, Renee C.; Garnero, Ed J.; Schmerr, Nicholas C.

2011-01-01

The Apollo Passive Seismic Experiment (APSE) consisted of four 3-component seismometers deployed between 1969 and 1972, that continuously recorded lunar ground motion until late 1977. The APSE data provide a unique opportunity for investigating the interior of a planet other than Earth, generating the most direct constraints on the elastic structure, and hence the thermal and compositional evolution of the Moon. Owing to the lack of far side moonquakes, past seismic models of the lunar interior were unable to constrain the lowermost 500 km of the interior. Recently, array methodologies aimed at detecting deep lunar seismic reflections found evidence for a lunar core, providing an elastic model of the deepest lunar interior consistent with geodetic parameters. Here we study the uncertainties in these models associated with the double array stacking of deep moonquakes for imaging deep reflectors in the Moon. We investigate the dependency of the array stacking results on a suite of parameters, including amplitude normalization assumptions, polarization filters, assumed velocity structure, and seismic phases that interfere with our desired target phases. These efforts are facilitated by the generation of synthetic seismograms at high frequencies (approx. 1Hz), allowing us to directly study the trade-offs between different parameters. We also investigate expected amplitudes of deep reflections relative to direct P and S arrivals, including predictions from arbitrarily oriented focal mechanisms in our synthetics. Results from separate versus combined station stacking help to establish the robustness of stacks. Synthetics for every path geometry of data were processed identically to that done with data. Different experiments were aimed at examining various processing assumptions, such as adding random noise to synthetics and mixing 3 components to some degree. The principal stacked energy peaks put forth in recent work persist, but their amplitude (which maps into reflector impedance contrast) and timing (which maps into reflector depth) depend on factors that are not well constrained -- most notably, the velocity structure of the overlying lunar interior. Thus, while evidence for the lunar core remains strong, the depths of imaged reflectors have associated uncertainties that will require new seismic data and observations to constrain. These results strongly advocate further investigations on the Moon to better resolve the interior (e.g., Selene missions), for the Moon apparently has a rich history of construction and evolution that is inextricably tied to that of Earth.

Global Lunar Topography from the Deep Space Gateway for Science and Exploration

NASA Astrophysics Data System (ADS)

Archinal, B.; Gaddis, L.; Kirk, R.; Edmundson, K.; Stone, T.; Portree, D.; Keszthelyi, L.

2018-02-01

The Deep Space Gateway, in low lunar orbit, could be used to achieve a long standing goal of lunar science, collecting stereo images in two months to make a complete, uniform, high resolution, known accuracy, global topographic model of the Moon.

Lunar Heat Flux Measurements Enabled by a Microwave Radiometer Aboard the Deep Space Gateway

NASA Astrophysics Data System (ADS)

Siegler, M.; Ruf, C.; Putzig, N.; Morgan, G.; Hayne, P.; Paige, D.; Nagihara, S.; Weber, R.

2018-02-01

We would like to present a concept to use the Deep Space Gateway as a platform for constraining the geothermal heat production, surface, and near-surface rocks, and dielectric properties of the Moon from orbit with passive microwave radiometery.

Lunar Science: Using the Moon as a Testbed

NASA Technical Reports Server (NTRS)

Taylor, G. J.

1993-01-01

The Moon is an excellent test bed for innovative instruments and spacecraft. Excellent science can be done, the Moon has a convenient location, and previous measurements have calibrated many parts of it. I summarize these attributes and give some suggestions for the types of future measurements. The Lunar Scout missions planned by NASA's Office of Exploration will not make all the measurements needed. Thus, test missions to the Moon can also return significant scientific results, making them more than technology demonstrations. The Moon is close to Earth, so cruise time is insignificant, tracking is precise, and some operations can be controlled from Earth, but it is in the deep space environment, allowing full tests of instruments and spacecraft components. The existing database on the Moon allows tests of new instruments against known information. The most precise data come from lunar samples, where detailed analyses of samples from a few places on the Moon provide data on chemical and mineralogical composition and physical properties.

Astronomy and Space Science from the Moon: Proceedings of Symposium E4 of the COSPAR 29th Plenary Meeting held in Washington, DC, 28 Aug.-5 Sep., 1992

NASA Technical Reports Server (NTRS)

Foing, B. H. (Editor)

1994-01-01

The goal of the conference was to assess the moon as a base for conducting astronomy, solar system observations, and space sciences. The lunar vacuum allows a complete opening of the electromagnetic window and distortion-free measurements at the highest angular resolution, precision, and temporal stability. The moon is perfect for continuous monitoring of the Sun, Solar System targets, and for deep observations of galactic and extragalactic objects. It is an in-situ laboratory for selenophysics, chemistry, and exobiology. The moon contains useful resources and is accessible from Earth for installation, operations maintenance, robotics, and human activities.

Physicochemical Requirements Inferred for Chemical Self-Organization Hardly Support an Emergence of Life in the Deep Oceans of Icy Moons.

PubMed

Pascal, Robert

2016-05-01

An approach to the origin of life, focused on the property of entities capable of reproducing themselves far from equilibrium, has been developed recently. Independently, the possibility of the emergence of life in the hydrothermal systems possibly present in the deep oceans below the frozen crust of some of the moons of Jupiter and Saturn has been raised. The present report is aimed at investigating the mutual compatibility of these alternative views. In this approach, the habitability concept deduced from the limits of life on Earth is considered to be inappropriate with regard to emerging life due to the requirement for an energy source of sufficient potential (equivalent to the potential of visible light). For these icy moons, no driving force would have been present to assist the process of emergence, which would then have had to rely exclusively on highly improbable events, thereby making the presence of life unlikely on these Solar System bodies, that is, unless additional processes are introduced for feeding chemical systems undergoing a transition toward life and the early living organisms. Icy moon-Bioenergetics-Chemical evolution-Habitability-Origin of life. Astrobiology 16, 328-334.

Science Goals and Objectives for Canadian Robotic Exploration of the Moon Enabled by the Deep Space Gateway

NASA Astrophysics Data System (ADS)

Bourassa, M.; Osinski, G. R.; Cross, M.; Hill, P.; King, D.; Morse, Z.; Pilles, E.; Tolometti, G.; Tornabene, L. L.; Zanetti, M.

2018-02-01

Canadian contributions to the science goals and objectives of a lunar precursor rover for HERACLES, an international mission concept, are discussed. Enabled by the Deep Space Gateway, this rover is a technical demonstrator for robotic sample return.

Deep Space Gateway Facilitates Exploration of Planetary Crusts: A Human/Robotic Exploration Design Reference Campaign to the Lunar Orientale Basin

NASA Astrophysics Data System (ADS)

Head, J. W.; Pieters, C. M.; Scott, D. R.

2018-02-01

We outline an Orientale Basin Human/Robotic Architecture that can be facilitated by a Deep Space Gateway International Science Operations Center (DSG-ISOC) (like McMurdo/Antarctica) to address fundamental scientific problems about the Moon and Mars.

Radiometric Calibration of Earth Science Imagers Using HyCalCam on the Deep Space Gateway Platform

NASA Astrophysics Data System (ADS)

Butler, J. J.; Thome, K. J.

2018-02-01

HyCalCam, an SI-traceable imaging spectrometer on the Deep Space Gateway, acquires images of the Moon and Earth to characterize the lunar surface and terrestrial scenes for use as absolute calibration targets for on-orbit LEO and GEO sensors.

The formation of the moon

NASA Technical Reports Server (NTRS)

O'Keefe, J. A., III

1974-01-01

Supporting evidence for the fission hypothesis for the origin of the moon is offered. The maximum allowable amount of free iron now present in the moon would not suffice to extract the siderophiles from the lunar silicates with the observed efficiency. Hence extraction must have been done with a larger amount of iron, as in the mantle of the earth, of which the moon was once a part, according to the fission hypothesis. The fission hypothesis gives a good resolution of the tektite paradox. Tektites are chemically much like products of the mantle of the earth; but no physically possible way has been found to explain their production from the earth itself. Perhaps they are a product of late, deep-seated lunar volcanism. If so, the moon must have inside it some material with a strong resemblance to the earth's mantle.

Association between lunar phase and sleep characteristics.

PubMed

Turányi, Csilla Zita; Rónai, Katalin Zsuzsanna; Zoller, Rezső; Véber, Orsolya; Czira, Mária Eszter; Újszászi, Ákos; László, Gergely; Szentkirályi, András; Dunai, Andrea; Lindner, Anett; Szőcs, Julianna Luca; Becze, Ádám; Kelemen, Andrea; Lendvai, Zsófia; Molnar, Miklos Z; Mucsi, István; Novák, Márta

2014-11-01

Popular belief holds that the lunar cycle affects human physiology, behavior, and health, including sleep. To date, only a few and conflicting analyses have been published about the association between lunar phases and sleep. Our aim was to analyze the relationship between lunar phases and sleep characteristics. In this retrospective, cross-sectional analysis, data from 319 patients who had been referred for sleep study were included. Individuals with apnea-hypopnea index ≥ 15/h were excluded. Socio-demographic parameters were recorded. All participants underwent one-night standard polysomnography. Associations between lunar cycle (new moon, full moon and alternate moon) and sleep parameters were examined in unadjusted and adjusted models. Fifty-seven percent of patients were males. Mean age for men was 45 ± 14 years and 51 ± 12 years for women. In total, 224 persons had their sleep study done during alternate moon, 47 during full moon, and 48 during new moon. Full moon was associated with lower sleep efficiency [median (%) (IQR): new moon 82 (18), full moon 74 (19), alternate moon 82 (15); P < 0.001], less deep sleep [median (%) (IQR): new moon 9 (9), full moon 6 (4), alternate moon 11 (9); P < 0.001], and increased REM latency [median (min) (IQR): new moon 98 (74), full moon 137 (152), alternate moon 97 (76); P < 0.001], even after adjustment for several covariables. The results are consistent with a recent report and the widely held belief that sleep characteristics may be associated with the full moon. Copyright © 2014 Elsevier B.V. All rights reserved.

Internal structure of the Moon inferred from Apollo seismic data and selenodetic data from GRAIL and LLR

NASA Astrophysics Data System (ADS)

Matsumoto, Koji; Yamada, Ryuhei; Kikuchi, Fuyuhiko; Kamata, Shunichi; Ishihara, Yoshiaki; Iwata, Takahiro; Hanada, Hideo; Sasaki, Sho

2015-09-01

The internal structure of the Moon is important for discussions on its origin and evolution. However, the deep structure of the Moon is still debated due to the absence of comprehensive seismic data. This study explores lunar interior models by complementing Apollo seismic travel time data with selenodetic data which have recently been improved by Gravity Recovery and Interior Laboratory (GRAIL) and Lunar Laser Ranging (LLR). The observed data can be explained by models including a deep-seated zone with a low velocity (S wave velocity = 2.9 ± 0.5 km/s) and a low viscosity (˜3 × 1016 Pa s). The thickness of this zone above the core-mantle boundary is larger than 170 km, showing a negative correlation with the radius of the fluid outer core. The inferred density of the lowermost mantle suggests a high TiO2 content (>11 wt.%) which prefers a mantle overturn scenario.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Payne, S. J.; Bruhn, D. F.; Hodges, J. M.

During 2012, the Idaho National Laboratory Seismic Monitoring Program evaluated 17,329 independent triggers that included earthquakes from around the world, the western United States, and local region of the Snake River Plain. Seismologists located 1,460 earthquakes and man-made blasts within and near the 161-km (or 100-mile) radius of the Idaho National Laboratory. Of these earthquakes, 16 had small-to-moderate size magnitudes (M) from 3.0 to 3.6. Within the 161-km radius, the majority of 695 earthquakes (M < 3.6) occurred in the active regions of the Basin and Range Provinces adjacent to the eastern Snake River Plain. Only 11 microearthquakes occurred withinmore » the Snake River Plain, four of which occurred in Craters of the Moon National Monument. The earthquakes had magnitudes from 1.0 to 1.7 and occurred at deep depths (11-24 km). Two events with magnitudes less than 1.0 occurred within the Idaho National Laboratory boundaries and had depths less than 10 km.« less

Global and Local Gravity Field Models of the Moon Using GRAIL Primary and Extended Mission Data

NASA Technical Reports Server (NTRS)

Goossens, Sander; Lemoine, Frank G.; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Loomis, Bryant D.; Chinn, Douglas S.; Neumann, Gregory A.; Smith, David E.;

Time and Energy, Exploring Trajectory Options Between Nodes in Earth-Moon Space

NASA Technical Reports Server (NTRS)

Martinez, Roland; Condon, Gerald; Williams, Jacob

2012-01-01

The Global Exploration Roadmap (GER) was released by the International Space Exploration Coordination Group (ISECG) in September of 2011. It describes mission scenarios that begin with the International Space Station and utilize it to demonstrate necessary technologies and capabilities prior to deployment of systems into Earth-Moon space. Deployment of these systems is an intermediate step in preparation for more complex deep space missions to near-Earth asteroids and eventually Mars. In one of the scenarios described in the GER, "Asteroid Next", there are activities that occur in Earth-Moon space at one of the Earth-Moon Lagrange (libration) points. In this regard, the authors examine the possible role of an intermediate staging point in an effort to illuminate potential trajectory options for conducting missions in Earth-Moon space of increasing duration, ultimately leading to deep space missions. This paper will describe several options for transits between Low Earth Orbit (LEO) and the libration points, transits between libration points, and transits between the libration points and interplanetary trajectories. The solution space provided will be constrained by selected orbital mechanics design techniques and physical characteristics of hardware to be used in both crewed missions and uncrewed missions. The relationships between time and energy required to transfer hardware between these locations will provide a better understanding of the potential trade-offs mission planners could consider in the development of capabilities, individual missions, and mission series in the context of the ISECG GER.

Evidence for an early wet Moon from experimental crystallization of the lunar magma ocean

NASA Astrophysics Data System (ADS)

Lin, Yanhao; Tronche, Elodie J.; Steenstra, Edgar S.; van Westrenen, Wim

2017-01-01

The Moon is thought to have been covered initially by a deep magma ocean, its gradual solidification leading to the formation of the plagioclase-rich highland crust. We performed a high-pressure, high-temperature experimental study of lunar mineralogical and geochemical evolution during magma ocean solidification that yields constraints on the presence of water in the earliest lunar interior. In the experiments, a deep layer containing both olivine and pyroxene is formed in the first ~50% of crystallization, β-quartz forms towards the end of crystallization, and the last per cent of magma remaining is extremely iron rich. In dry experiments, plagioclase appears after 68 vol.% solidification and yields a floatation crust with a thickness of ~68 km, far above the observed average of 34-43 km based on lunar gravity. The volume of plagioclase formed during crystallization is significantly less in water-bearing experiments. Using the relationship between magma water content and the resulting crustal thickness in the experiments, and considering uncertainties in initial lunar magma ocean depth, we estimate that the Moon may have contained at least 270 to 1,650 ppm water at the time of magma ocean crystallization, suggesting the Earth-Moon system was water-rich from the start.

Preliminary Results on Lunar Interior Properties from the GRAIL Mission

NASA Technical Reports Server (NTRS)

Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, H. Jay; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.;

Particle Radiation Sources, Propagation and Interactions in Deep Space, at Earth, the Moon, Mars, and Beyond: Examples of Radiation Interactions and Effects

NASA Astrophysics Data System (ADS)

Schwadron, Nathan A.; Cooper, John F.; Desai, Mihir; Downs, Cooper; Gorby, Matt; Jordan, Andrew P.; Joyce, Colin J.; Kozarev, Kamen; Linker, Jon A.; Mikíc, Zoran; Riley, Pete; Spence, Harlan E.; Török, Tibor; Townsend, Lawrence W.; Wilson, Jody K.; Zeitlin, Cary

2017-11-01

Particle radiation has significant effects for astronauts, satellites and planetary bodies throughout the Solar System. Acute space radiation hazards pose risks to human and robotic exploration. This radiation also naturally weathers the exposed surface regolith of the Moon, the two moons of Mars, and other airless bodies, and contributes to chemical evolution of planetary atmospheres at Earth, Mars, Venus, Titan, and Pluto. We provide a select review of recent areas of research covering the origin of SEPs from coronal mass ejections low in the corona, propagation of events through the solar system during the anomalously weak solar cycle 24 and important examples of radiation interactions for Earth, other planets and airless bodies such as the Moon.

Design and Experimental Verification of Chang'E-3 Moon-night Survival Device for APXS

NASA Astrophysics Data System (ADS)

Deng-yi, Chen; Jian, Wu; Yi-ming, Hu; Jin, Chang; Yi-zhong, Gong; Ming-sheng, Cai; Huan-yu, Wang; Jia-yu, Zhang; Xing-zhu, Cui; Jin-zhou, Wang

2016-07-01

The Active Particle X-ray Spectrometer (APXS) is one of the 4 scientific payloads of Chang'E-3 (CE-3) Lunar Rover, of which the scientific object is to identify the elements of lunar soil and rock samples by a carried radioactive source to trigger and detect the characteristic X-ray from them. According to the extreme temperature environment of the APXS and under the restriction of limited resources, this paper presents the design and analysis of the moon-night survival device RHU (radioisotope heating unit) for the APXS, and describes the corresponding environmental tests on its structure dynamics and moon-night survival. Finally, its reinstallation on the launch tower and the preliminary result of its on-orbit operation are introduced.

Gravity fields. [Jovian, Martian, Cytherean, Mercurian and lunar mass distributions

NASA Technical Reports Server (NTRS)

Sjogren, W. L.; Anderson, J. D.; Phillips, R. J.; Trask, D. W.

1976-01-01

Detailed results on internal mass distribution have been obtained via earth-based Doppler radio tracking of deep space probes in the case of Mars, the earth's moon, Venus, Mercury, and Jupiter. Global gravity fields show close correlation with topography in the case of the moon and Mars, as data from orbiting spacecraft indicate. Some data are available on Jovian satellites. The gravity measuring instrumentation and data reduction techniques are described. Gravity profiles referable to lunar frontside mascons, craters, and mountain chains have been acquired from low-altitude (15-20 km) orbit surveys. Theoretically based cross sections through the moon and Jupiter are presented.

A diffusion source for sodium and potassium in the atmospheres of Mercury and the moon

NASA Technical Reports Server (NTRS)

Sprague, Ann L.

1990-01-01

Deep grain-boundary diffusion and regolith diffusion through a fractured crust and regolith can account not only for the Na/K ratios observed in the Mercurian and lunar atmospheres, but the large Na abundance enhancement of Mercury over lunar levels. A hot component of Na and K at Mercury is noted to be smaller in proportion to the total abundances of these two constituents than at the moon; this hot component is consistent with a population of meteoritic substances similar to lunar ones, as well as with a surface composition which has undergone no greater K depletion than that of the moon.

Physicochemical Requirements Inferred for Chemical Self-Organization Hardly Support an Emergence of Life in the Deep Oceans of Icy Moons

NASA Astrophysics Data System (ADS)

Pascal, Robert

2016-05-01

An approach to the origin of life, focused on the property of entities capable of reproducing themselves far from equilibrium, has been developed recently. Independently, the possibility of the emergence of life in the hydrothermal systems possibly present in the deep oceans below the frozen crust of some of the moons of Jupiter and Saturn has been raised. The present report is aimed at investigating the mutual compatibility of these alternative views. In this approach, the habitability concept deduced from the limits of life on Earth is considered to be inappropriate with regard to emerging life due to the requirement for an energy source of sufficient potential (equivalent to the potential of visible light). For these icy moons, no driving force would have been present to assist the process of emergence, which would then have had to rely exclusively on highly improbable events, thereby making the presence of life unlikely on these Solar System bodies, that is, unless additional processes are introduced for feeding chemical systems undergoing a transition toward life and the early living organisms.

Tremor evidence for dynamically triggered creep events on the deep San Andreas Fault

NASA Astrophysics Data System (ADS)

Peng, Z.; Shelly, D. R.; Hill, D. P.; Aiken, C.

2010-12-01

Deep tectonic tremor has been observed along major subduction zones and the San Andreas fault (SAF) in central and southern California. It appears to reflect deep fault slip, and it is often seen to be triggered by small stresses, including passing seismic waves from large regional and teleseismic earthquakes. Here we examine tremor activity along the Parkfield-Cholame section of the SAF from mid-2001 to early 2010, scrutinizing its relationship with regional and teleseismic earthquakes. Based on similarities in the shape and timing of seismic waveforms, we conclude that triggered and ambient tremor share common sources and a common physical mechanism. Utilizing this similarity in waveforms, we detect tremor triggered by numerous large events, including previously unreported triggering from the recent 2009 Mw7.3 Honduras, 2009 Mw8.1 Samoa, and 2010 Mw8.8 Chile earthquakes at teleseismic distances, and the relatively small 2007 Mw5.4 Alum Rock and 2008 Mw5.4 Chino Hills earthquakes at regional distances. We also find multiple examples of systematic migration in triggered tremor, similar to ambient tremor migration episodes observed at other times. Because these episodes propagate much more slowly than the triggering waves, the migration likely reflects a small, triggered creep event. As with ambient tremor bursts, triggered tremor at times persists for multiple days, probably indicating a somewhat larger creep event. This activity provides a clear example of delayed dynamic triggering, with a mechanism perhaps also relevant for triggering of regular earthquakes.

A wet, heterogeneous lunar interior: Lower mantle and core dynamo evolution

NASA Astrophysics Data System (ADS)

Evans, A. J.; Zuber, M. T.; Weiss, B. P.; Tikoo, S. M.

2014-05-01

While recent analyses of lunar samples indicate the Moon had a core dynamo from at least 4.2-3.56 Ga, mantle convection models of the Moon yield inadequate heat flux at the core-mantle boundary to sustain thermal core convection for such a long time. Past investigations of lunar dynamos have focused on a generally homogeneous, relatively dry Moon, while an initial compositionally stratified mantle is the expected consequence of a postaccretionary lunar magma ocean. Furthermore, recent re-examination of Apollo samples and geophysical data suggests that the Moon contains at least some regions with high water content. Using a finite element model, we investigate the possible consequences of a heterogeneously wet, compositionally stratified interior for the evolution of the Moon. We find that a postoverturn model of mantle cumulates could result in a core heat flux sufficiently high to sustain a dynamo through 2.5 Ga and a maximum surface, dipolar magnetic field strength of less than 1 μT for a 350-km core and near ˜2 μT for a 450-km core. We find that if water was transported or retained preferentially in the deep interior, it would have played a significant role in transporting heat out of the deep interior and reducing the lower mantle temperature. Thus, water, if enriched in the lower mantle, could have influenced core dynamo timing by over 1.0 Gyr and enhanced the vigor of a lunar core dynamo. Our results demonstrate the plausibility of a convective lunar core dynamo even beyond the period currently indicated by the Apollo samples.

MPST Software: MoonKommand

NASA Technical Reports Server (NTRS)

Kwok, John H.; Call, Jared A.; Khanampornpan, Teerapat

2012-01-01

This software automatically processes Sally Ride Science (SRS) delivered MoonKAM camera control files (ccf) into uplink products for the GRAIL-A and GRAIL-B spacecraft as part of an education and public outreach (EPO) extension to the Grail Mission. Once properly validated and deemed safe for execution onboard the spacecraft, MoonKommand generates the command products via the Automated Sequence Processor (ASP) and generates uplink (.scmf) files for radiation to the Grail-A and/or Grail-B spacecraft. Any errors detected along the way are reported back to SRS via email. With Moon Kommand, SRS can control their EPO instrument as part of a fully automated process. Inputs are received from SRS as either image capture files (.ccficd) for new image requests, or downlink/delete files (.ccfdl) for requesting image downlink from the instrument and on-board memory management. The Moon - Kommand outputs are command and file-load (.scmf) files that will be uplinked by the Deep Space Network (DSN). Without MoonKommand software, uplink product generation for the MoonKAM instrument would be a manual process. The software is specific to the Moon - KAM instrument on the GRAIL mission. At the time of this writing, the GRAIL mission was making final preparations to begin the science phase, which was scheduled to continue until June 2012.

Solid state convection models of lunar internal temperature

NASA Technical Reports Server (NTRS)

Schubert, G.; Young, R. E.; Cassen, P.

1975-01-01

Thermal models of the Moon were made which include cooling by subsolidus creep and consideration of the creep behavior of geologic material. Measurements from the Apollo program on seismic velocities, electrical conductivity of the Moon's interior, and heat flux at two locations were used in the calculations. Estimates of 1500 to 1600 K were calculated for the temperature, and one sextillion to ten sextillion sq cm/sec were calcualted for the viscosity of the deep lunar interior.

Design and Hardware-in-the-Loop Implementation of Optimal Canonical Maneuvers for an Autonomous Planetary Aerial Vehicle

DTIC Science & Technology

2012-12-01

selflessly working your own school and writing schedule around mine , supporting me throughout career paths that have been anything but traditional...observation, and other scientific research and exploration purposes. 4 A ground rover on a planet, moon, or other body such as an asteroid must...applied to autonomous craft that could eventually operate on the surface of planets, moons, and asteroids , as well as in Earth orbit or deep space

The Use of Standards on the LADEE Mission

NASA Technical Reports Server (NTRS)

Gundy-Burlet, Karen

2015-01-01

The Lunar Atmosphere Dust Environment Explorer (LADEE) was a small explorer class mission that launched Sept 7, 2013 and successfully de-orbited and impacted the moon's surface on April 17, 2014. The spacecraft was the first to launch from a Minotaur 5 and was the first deep space mission to launch from the Wallops flight facility. Figure 1 shows the famous image of a frog unlucky enough to be launched from the facility at the same time as LADEE. The science mission for the spacecraft was to determine the density, composition and variability of the lunar exosphere. In addition, it performed a first-of-a-kind demonstration of laser-based communications from deep space that exhibited a record downlink rate of 622 megabits per second from the moon. In order to perform the lunar dust surveys, the spacecraft was placed in a retrograde equatorial orbit with periapsis between 20 and 60 kilometers. The mission was granted an extension in which final science surveys were performed at altitudes as low as 2 kilometers over the moon's surface. The cadence for spacecraft operations was demanding: the moon's highly inhomogeneous gravity field distorted the orbit, the regular maneuvers were subject to strict payload-induced pointing requirements, and there were periodic attitude changes to keep the spacecraft thermally safe. This led to a need for high reliability in the operation of the spacecraft while obeying strict budget and schedule guidelines.

Formation and composition of the moon

NASA Technical Reports Server (NTRS)

Anderson, D. L.

1977-01-01

Many of the properties of the Moon, including the enrichment in Ca, Al, Ti, U, Th, Ba, Sr, and the REE and the depletion in Fe, Rb, K, Na, and other volatiles can be understood if the Moon represents a high-temperature condensate from the solar nebula. Thermodynamic calculations show that Ca-, Al-, and Ti-rich compounds condense first in a cooling nebula. The initial high temperature mineralogy is gehlenite, spinel, perovskite, Ca-Al-rich pyroxenes, and anorthite. Inclusions in carbonaceous chondrites such as the Allende meteorite are composed primarily of these minerals and, in addition, are highly enriched in refractories such as REE relative to carbonaceous chondrites. These inclusions can yield basalt and anorthosite in the proportions required to eliminate the europium anomaly, leaving a residual spinel-melilite interior. A deep interior high in Ca-Al does not imply an unacceptable mean density or moment of inertia for the Moon. The inferred high-U content of the lunar interior, both from the Allende analog and the high heat flow, indicates a high-temperature interior. The model is consistent with extensive early melting, with shallow melting at 3 AE, and with presently high deep internal temperatures. It is predicted that the outer 250 km is rich in plagioclase and FeO. The low iron content of the interior in this model raises the interior temperatures estimated from electrical conductivity by some 800 C.

Influence of Tidal Forces on the Triggering of Seismic Events

NASA Astrophysics Data System (ADS)

Varga, Péter; Grafarend, Erik

2018-05-01

Tidal stresses are generated in any three-dimensional body influenced by an external inhomogeneous gravity field of rotating planets or moons. In this paper, as a special case, stresses caused within the solid Earth by the body tides are discussed from viewpoint of their influence on seismic activity. The earthquake triggering effects of the Moon and Sun are usually investigated by statistical comparison of tidal variations and temporal distribution of earthquake activity, or with the use of mathematical or experimental modelling of physical processes in earthquake prone structures. In this study, the magnitude of the lunisolar stress tensor in terms of its components along the latitude of the spherical surface of the Earth as well as inside the Earth (up to the core-mantle boundary) were calculated for the PREM (Dziewonski and Anderson in Phys Earth Planet Inter 25(4):297-356, 1981). Results of calculations prove that stress increases as a function of depth reaching a value around some kPa at the depth of 900-1500 km, well below the zone of deep earthquakes. At the depth of the overwhelming part of seismic energy accumulation (around 50 km) the stresses of lunisolar origin are only (0.0-1.0)·103 Pa. Despite the fact that these values are much smaller than the earthquake stress drops (1-30 MPa) (Kanamori in Annu Rev Earth Planet Sci 22:207-237, 1994) this does not exclude the possibility of an impact of tidal forces on outbreak of seismic events. Since the tidal potential and its derivatives are coordinate dependent and the zonal, tesseral and sectorial tides have different distributions from the surface down to the CMB, the lunisolar stress cannot influence the break-out of every seismological event in the same degree. The influencing lunisolar effect of the solid earth tides on earthquake occurrences is connected first of all with stress components acting parallel to the surface of the Earth. The influence of load tides is limited to the loaded area and its immediate vicinity.

Influence of Tidal Forces on the Triggering of Seismic Events

NASA Astrophysics Data System (ADS)

Varga, Péter; Grafarend, Erik

2017-05-01

Tidal stresses are generated in any three-dimensional body influenced by an external inhomogeneous gravity field of rotating planets or moons. In this paper, as a special case, stresses caused within the solid Earth by the body tides are discussed from viewpoint of their influence on seismic activity. The earthquake triggering effects of the Moon and Sun are usually investigated by statistical comparison of tidal variations and temporal distribution of earthquake activity, or with the use of mathematical or experimental modelling of physical processes in earthquake prone structures. In this study, the magnitude of the lunisolar stress tensor in terms of its components along the latitude of the spherical surface of the Earth as well as inside the Earth (up to the core-mantle boundary) were calculated for the PREM (Dziewonski and Anderson in Phys Earth Planet Inter 25(4):297-356, 1981). Results of calculations prove that stress increases as a function of depth reaching a value around some kPa at the depth of 900-1500 km, well below the zone of deep earthquakes. At the depth of the overwhelming part of seismic energy accumulation (around 50 km) the stresses of lunisolar origin are only (0.0-1.0)·103 Pa. Despite the fact that these values are much smaller than the earthquake stress drops (1-30 MPa) (Kanamori in Annu Rev Earth Planet Sci 22:207-237, 1994) this does not exclude the possibility of an impact of tidal forces on outbreak of seismic events. Since the tidal potential and its derivatives are coordinate dependent and the zonal, tesseral and sectorial tides have different distributions from the surface down to the CMB, the lunisolar stress cannot influence the break-out of every seismological event in the same degree. The influencing lunisolar effect of the solid earth tides on earthquake occurrences is connected first of all with stress components acting parallel to the surface of the Earth. The influence of load tides is limited to the loaded area and its immediate vicinity.

Goldstone solar system radar

NASA Technical Reports Server (NTRS)

Jurgens, R. F.; Clark, P. E.; Goldstein, R. M.; Ostro, S. J.; Slade, M. A.; Thompson, T. W.; Saunders, R. S.

1986-01-01

Information is provided about physical nature planetary surfaces and their topography as well as dynamical properties such as orbits and spin states using ground based radar as a remote sensing tool. Accessible targets are the terrestrial planets: the Earth's Moon, Mercury, Venus and Mars, the outer planets rings and major moons, and many transient objects such as asteroids and comets. Data acquisition utilizes the unique facilities of the Goldstone Deep Space Network, occasionally the Arecibo radar, and proposed use of the VLA (very large array).

Lunar seismicity and tectonics

NASA Technical Reports Server (NTRS)

Lammlein, D. R.

1977-01-01

Results are presented for an analysis of all moonquake data obtained by the Apollo seismic stations during the period from November 1969 to May 1974 and a preliminary analysis of critical data obtained in the interval from May 1974 to May 1975. More accurate locations are found for previously located moonquakes, and additional sources are located. Consideration is given to the sources of natural seismic signals, lunar seismic activity, moonquake periodicities, tidal periodicities in moonquake activity, hypocentral locations and occurrence characteristics of deep and shallow moonquakes, lunar tidal control over moonquakes, lunar tectonism, the locations of moonquake belts, and the dynamics of the lunar interior. It is concluded that: (1) moonquakes are distributed in several major belts of global extent that coincide with regions of the youngest and most intense volcanic and tectonic activity; (2) lunar tides control both the small quakes occurring at great depth and the larger quakes occurring near the surface; (3) the moon has a much thicker lithosphere than earth; (4) a single tectonic mechanism may account for all lunar seismic activity; and (5) lunar tidal stresses are an efficient triggering mechanism for moonquakes.

50 CFR 660.112 - Trawl fishery-prohibitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... reports of groundfish landings, containing all data, and in the exact manner, required by the regulation.../Biogenic Area, Farallon Islands/Fanny Shoal, Half Moon Bay, Monterey Bay/Canyon, Point Sur Deep, Big Sur...

The Ring Sculptor

NASA Image and Video Library

2006-09-08

Prometheus zooms across the Cassini spacecraft field of view, attended by faint streamers and deep gores in the F ring. This movie sequence of five images shows the F ring shepherd moon shaping the ring inner edge

An Integrated Science Glovebox for the Gateway Habitat

NASA Astrophysics Data System (ADS)

Calaway, M. J.; Evans, C. A.; Garrison, D. H.; Bell, M. S.

2018-02-01

A Deep Space Gateway astromaterials glovebox facility would enable science to return to Earth collected astromaterials from the Moon and ultimately Mars. Next generation habitats will benefit from on-board glovebox capability.

The first laboratory measurements of sulfur ions sputtering water ice

NASA Astrophysics Data System (ADS)

Galli, André; Pommerol, Antoine; Vorburger, Audrey; Wurz, Peter; Tulej, Marek; Scheer, Jürgen; Thomas, Nicolas; Wieser, Martin; Barabash, Stas

2015-04-01

The upcoming JUpiter ICy moons Explorer mission to Europa, Ganymede, and Callisto has renewed the interest in the interaction of plasma with an icy surface. In particular, the surface release processes on which exosphere models of icy moons rely should be tested with realistic laboratory experiments. We therefore use an existing laboratory facility for space hardware calibration in vacuum to measure the sputtering of water ice due to hydrogen, oxygen, and sulfur ions at energies from 1 keV to 100 keV. Pressure and temperature are comparable to surface conditions encountered on Jupiter's icy moons. The sputter target is a 1cm deep layer of porous, salty water ice. Our results confirm theoretical predictions that the sputter yield from oxygen and sulfur ions should be similar. Thanks to the modular set-up of our experiment we can add further surface processes relevant for icy moons, such as electron sputtering, sublimation, and photodesorption due to UV light.

From a Million Miles Away, NASA Camera Shows Moon Crossing Face of Earth

NASA Image and Video Library

2015-08-05

This animation still image shows the far side of the moon, illuminated by the sun, as it crosses between the DISCOVR spacecraft's Earth Polychromatic Imaging Camera (EPIC) camera and telescope, and the Earth - one million miles away. Credits: NASA/NOAA A NASA camera aboard the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the moon as it moved in front of the sunlit side of Earth last month. The series of test images shows the fully illuminated “dark side” of the moon that is never visible from Earth. The images were captured by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope on the DSCOVR satellite orbiting 1 million miles from Earth. From its position between the sun and Earth, DSCOVR conducts its primary mission of real-time solar wind monitoring for the National Oceanic and Atmospheric Administration (NOAA).

Capture of terrestrial-sized moons by gas giant planets.

PubMed

Williams, Darren M

2013-04-01

Terrestrial moons with masses >0.1 M (symbol in text) possibly exist around extrasolar giant planets, and here we consider the energetics of how they might form. Binary-exchange capture can occur if a binary-terrestrial object (BTO) is tidally disrupted during a close encounter with a giant planet and one of the binary members is ejected while the other remains as a moon. Tidal disruption occurs readily in the deep gravity wells of giant planets; however, the large encounter velocities in the wells make binary exchange more difficult than for planets of lesser mass. In addition, successful capture favors massive binaries with large rotational velocities and small component mass ratios. Also, since the interaction tends to leave the captured moons on highly elliptical orbits, permanent capture is only possible around planets with sizable Hill spheres that are well separated from their host stars.

Delayed dynamic triggering of deep tremor along the Parkfield-Cholame section of the San Andreas Fault following the 2014 M6.0 South Napa earthquake

USGS Publications Warehouse

Peng, Zhigang; Shelly, David R.; Ellsworth, William L.

2015-01-01

Large, distant earthquakes are known to trigger deep tectonic tremor along the San Andreas Fault and in subduction zones. However, there are relatively few observations of triggering from regional distance earthquakes. Here we show that a small tremor episode about 12–18 km NW of Parkfield was triggered during and immediately following the passage of surface waves from the 2014 Mw 6.0 South Napa main shock. More notably, a major tremor episode followed, beginning about 12 h later, and centered SE of Parkfield near Cholame. This major episode is one of the largest seen over the past several years, containing intense activity for ~3 days and taking more than 3 weeks to return to background levels. This episode showed systematic along-strike migration at ~5 km/d, suggesting that it was driven by a slow-slip event. Our results suggest that moderate-size earthquakes are capable of triggering major tremor and deep slow slip at regional distances.

Applying new seismic analysis techniques to the lunar seismic dataset: New information about the Moon and planetary seismology on the eve of InSight

NASA Astrophysics Data System (ADS)

Dimech, J. L.; Weber, R. C.; Knapmeyer-Endrun, B.; Arnold, R.; Savage, M. K.

2016-12-01

The field of planetary science is poised for a major advance with the upcoming InSight mission to Mars due to launch in May 2018. Seismic analysis techniques adapted for use on planetary data are therefore highly relevant to the field. The heart of this project is in the application of new seismic analysis techniques to the lunar seismic dataset to learn more about the Moon's crust and mantle structure, with particular emphasis on `deep' moonquakes which are situated half-way between the lunar surface and its core with no surface expression. Techniques proven to work on the Moon might also be beneficial for InSight and future planetary seismology missions which face similar technical challenges. The techniques include: (1) an event-detection and classification algorithm based on `Hidden Markov Models' to reclassify known moonquakes and look for new ones. Apollo 17 gravimeter and geophone data will also be included in this effort. (2) Measurements of anisotropy in the lunar mantle and crust using `shear-wave splitting'. Preliminary measurements on deep moonquakes using the MFAST program are encouraging, and continued evaluation may reveal new structural information on the Moon's mantle. (3) Probabilistic moonquake locations using NonLinLoc, a non-linear hypocenter location technique, using a modified version of the codes designed to work with the Moon's radius. Successful application may provide a new catalog of moonquake locations with rigorous uncertainty information, which would be a valuable input into: (4) new fault plane constraints from focal mechanisms using a novel approach to Bayes' theorem which factor in uncertainties in hypocenter coordinates and S-P amplitude ratios. Preliminary results, such as shear-wave splitting measurements, will be presented and discussed.

Apollo astronaut supports return to the Moon

NASA Astrophysics Data System (ADS)

Showstack, Randy

2012-12-01

Nearly 40 years after the Apollo 17 Moon launch on 7 December 1972, former NASA astronaut Harrison Schmitt said there is "no question" that the Moon is still worth going to, "whether you think about the science of the Moon or the resources of the Moon, or its relationship to accelerating our progress toward Mars." Schmitt, a geologist and the lunar module pilot for that final Apollo mission, was speaking at a 6 December news briefing about lunar science at the AGU Fall Meeting. "By going back to the Moon, you accelerate your ability to go anywhere else," Schmitt said, because of the ability to gain experience on a solar system body just a 3-day journey from Earth; test new hardware and navigation and communication techniques; and utilize lunar resources such as water, hydrogen, methane, and helium-3. He said lunar missions also would be a way "to develop new generations of people who know how to work in deep space. The people who know how to work [there] are my age, if not older, and we need young people to get that kind of experience." Schmitt, 77, said that a particularly interesting single location to explore would be the Aitken Basin at the Moon's south pole, where a crater may have reached into the Moon's upper mantle. He also said a longer duration exploration program might be able to explore multiple sites.

The U.S. Rosetta Project: Mars Gravity Assist

NASA Technical Reports Server (NTRS)

Alexander, Claudia; Holmes, Dwight P.; Goldstein, R.; Parker, Joel

2008-01-01

Since launch on March 2, 2004, the International Rosetta Mission has flown by the Earth/Moon system one time and conducted several distant observations of comets, including support for the Deep Impact measurements of comet 9 P/Tempel 1. In 2007, Rosetta flew by Mars for a gravity assist, and conducted observations of the Martian upper atmosphere as well as extended observations, in support of the New Horizons Jupiter encounter, of the Jovian magnetotail and Io torus. In late 2007 Rosetta had its second encounter with the Earth/Moon system. NASA's contribution to the Rosetta mission consists of three hardware experiments, and the portion of the electronics package for a fourth, as well as the participation of an Interdisciplinary Scientist (IDS); backup tracking, telecommunications, and navigation assurance provided by the Deep Space Network (DSN); support for the scientific participation of U.S. investigators on non-U.S. PI-led experiments. Collectively these elements are known as the U.S. Rosetta Project. In this paper we will update the status of the instruments following the both the Mars and Earth/Moon gravity assists. In addition, we will present a summary of the science observations for both Mars and Jupiter. 12.

Scattering attenuation profile of the Moon: Implications for shallow moonquakes and the structure of the megaregolith

NASA Astrophysics Data System (ADS)

Gillet, K.; Margerin, L.; Calvet, M.; Monnereau, M.

2017-01-01

We report measurements of the attenuation of short period seismic waves in the Moon based on the quantitative analysis of envelope records of lunar quakes. Our dataset consists of waveforms corresponding to 62 events, including artificial and natural impacts, shallow moonquakes and deep moonquakes, recorded by the four seismometers deployed during Apollo missions 12, 14, 15 and 16. To quantify attenuation and distinguish between elastic (scattering) and inelastic (absorption) mechanisms we measure the time of arrival of the maximum of energy tmax and the coda quality factor Qc . The former is controlled by both scattering and absorption, while the latter is an excellent proxy for absorption. Consistent with the strong broadening of seismogram envelopes in the Moon, we employ diffusion theory in spherical geometry to model the propagation of seismic energy in depth-dependent scattering and absorbing media. To minimize the misfit between predicted and observed tmax for deep moonquakes and impacts, we employ a genetic algorithm and explore a large number of depth-dependent attenuation models quantified by the scattering quality factor Qsc or equivalently the wave diffusivity D, and the absorption quality factor Qi . The scattering and absorption profiles that best fit the data display very strong scattering attenuation (Qsc ≤ 10) or equivalently very low wave diffusivity (D ≈ 2 km2/s) in the first 10 km of the Moon. These values correspond to the most heterogeneous regions on Earth, namely volcanic areas. Below this surficial layer, the diffusivity rises very slowly up to a depth of approximately 80 km where Qsc and D exhibit an abrupt increase of about one order of magnitude. Below 100 km depth, Qsc increases rapidly up to approximately 2000 at a depth of about 150 km, a value similar to the one found in the Earth's mantle. By contrast, the absorption quality factor on the Moon Qi ≈ 2400 is about one order or magnitude larger than on Earth. Our results suggest the existence of an approximately 100 km thick megaregolith, which is much larger than what was previously thought. The rapid decrease of scattering attenuation below this depth is compatible with crack healing through viscoelastic mechanisms. Using our best attenuation model, we invert for the depth of shallow moonquakes based on the observed variation of tmax with epicentral distance. On average, they are found to originate from a depth of about 50 km ± 20 km, which suggests that these earthquakes are caused by the failure of deep faults in the brittle part of the Moon.

Wind Tunnel Testing Underway for Next, More Powerful Version of NASA SLS Rocket

NASA Image and Video Library

2017-01-24

Engineers at NASA's Langley Research Center and Ames Research Center are running tests in supersonic wind tunnels to develop the next, more powerful version of the world's most advanced launch vehicle, the Space Launch System -- capable of carrying humans to deep space destinations. The new wind tunnel tests are for the second generation of SLS. It will deliver a 105-metric-ton (115-ton) lift capacity and will be 364 feet tall in the crew configuration -- taller than the Saturn V that launched astronauts on missions to the moon. The rocket's core stage will be the same, but the newer rocket will feature a powerful exploration upper stage. On SLS’s second flight with Orion, the rocket will carry up to four astronauts on a mission around the moon, in the deep-space proving ground for the technologies and capabilities needed on NASA’s Journey to Mars.

The AMERE project: Enabling real-time detection of radiation effects in individual cells in deep space

NASA Astrophysics Data System (ADS)

De Vos, Winnok H.; Meesen, Geert; Szpirer, Cedric; Scohy, Sophie; Cherukuri, Chaitanya; Evrard, Olivier; Hutsebaut, Xavier; Beghuin, Didier

2012-12-01

A major concern for long-term deep space missions is the detrimental impact of cosmic radiation on human health. Especially the presence of high-energy particles of high atomic mass (HZE) represents a serious threat. To contribute to a fundamental understanding of space radiation effects and to help improving risk assessment for humans on the Moon, the ESA Lunar Lander mission model payload includes a package dedicated to cell-based radiobiology experiments in the form of an Autonomous Microscope for Examination of Radiation Effects (AMERE). The purpose of this setup is to enable real-time visualization of DNA damage repair in living cells after traversal of HZE particles on the Moon. To assess the feasibility of this challenging experiment, we have analysed the biological and technological demands. In this article, we discuss the experimental concept, the biological considerations and describe the implications for system design.

Earthquakes - on the moon

NASA Technical Reports Server (NTRS)

Nakamura, Y.

1981-01-01

Information obtained with the Apollo lunar seismic stations is discussed. The four types of natural seismic sources that have been identified are described, viz., thermal moonquakes, deep moonquakes, meteoroid impacts, and shallow moonquakes. It is suggested that: (1) the thermal quakes represent the slow cracking and movement of surface rocks; (2) the deep quakes are induced by the tide-generating force of the earth's gravity; (3) the meteoroids responsible for most of the observed impacts are in the mass range from 1 to 100 kg and are clustered in groups near the earth's orbit; and (4) the shallow quakes are similar to intraplate earthquakes and indicate that the moon is as seismically active as the interior regions of the earth's tectonic plates. The structure of the lunar interior as inferred from seismic signals due to both the last three natural sources and 'artificial' impacts of used spacecraft is examined in detail.

Mass Wasting in Planetary Environments: Implications for Seismicity

NASA Technical Reports Server (NTRS)

Weber, Renee; Nahm, Amanda; Schmerr, Nick

2015-01-01

On Earth, mass wasting events such as rock falls and landslides are well known consequences of seismic activity. Here we investigate the regional effects of seismicity in planetary environments with the goal of determining whether such surface features on the Moon, Mars, and Mercury could be triggered by fault motion.

Earthquake triggering, Earth's rotation variations, Meton's cycle and torques acting on the Earth.

NASA Astrophysics Data System (ADS)

Ostrihansky, L.

2012-04-01

In contrast to unsuccessful searching (lasting over 150 years) of correlation of earthquakes with biweekly tides the author found correlation of earthquakes with sidereal 13.66 days Earth's rotation variations expressed as the length of a day (LOD) measured daily by the International Earth's Rotation Service. After short mention about earthquakes Denali Fault Alaska 3rd November 2002, M 7.9, triggered on LOD maximum and Great Sumatra earthquake 26th December 2004 triggered on LOD minimum and the full Moon, the main object of this paper are earthquakes of period 2010-VI. 2011: Haiti M 7.0 Jan. 12, 2010 on LOD minimum, Maule Chile M 8.8 Feb. 12, 2010 on LOD maximum, Sumatra and Andaman Sea region 6 earthquakes revealed from 7 on LOD minimum, New Zealand, Christchurch M 7.1 Sep. 9, 2010 on LOD minimum and Christchurch M 6.3 Feb. 21, 2011 on LOD maximum and Japan Near coast of Honshu M 9.1 March 11, 2011 on LOD minimum. I found that LOD minimums coincide with full or new Moon only twice in a year in solstices and also twice in the year with LOD maximums in equinoxes. To prove that determined coincidences of earthquakes and LOD extremes stated above are not accidental events, histograms were constructed of earthquake occurrence and their position on LOD graph deeply in the past, in some cases from the time the IERS started to measure the Earth's rotation variations in 1962. Evaluation of histograms and the Schuster's test has proven that maxima of earthquakes are triggered always in both Earth's rotation deceleration and acceleration. Backward overview of the past earthquakes revealed that the Great Sumatra earthquake Dec. 26, 2004 had its equivalent in the shape of LOD graph, full Moon position, character of aftershocks, 19 years ago in difference only one day of Dec. 27, 1985 M 6.6, proving that not only sidereal 13.66 days variations but also the 19 years Meton's cycle is the period of the earthquakes occurrence.

S-191 sensor performance evaluation

NASA Technical Reports Server (NTRS)

Hughes, C. L.

1975-01-01

A final analysis was performed on the Skylab S-191 spectrometer data received from missions SL-2, SL-3, and SL-4. The repeatability and accuracy of the S-191 spectroradiometric internal calibration was determined by correlation to the output obtained from well-defined external targets. These included targets on the moon and earth as well as deep space. In addition, the accuracy of the S-191 short wavelength autocalibration was flight checked by correlation of the earth resources experimental package S-191 outputs and the Backup Unit S-191 outputs after viewing selected targets on the moon.

Radio Science Concepts and Approaches for Jupiter Icy Moons Orbiter

NASA Technical Reports Server (NTRS)

Anderson, J. D.; Asmar, S. W.; Castillo, J. C.; Folkner, W. M.; Konopliv, A. S.; Marouf, E. A.; Rappaport, N. J.; Schubert, G.; Spilker, T. R.; Tyler, G. L.

2003-01-01

Radio Science experiments have been conducted on most deep space missions leading to numerous scientific discoveries. A set of concepts and approaches are proposed for the Jupiter Icy Moons Orbiter (JIMO) to apply Radio Science tools to investigate the interior structures of the Galilean Satellites and address key questions on their thermal and dynamical evolution. Measurements are identified that utilize the spacecraft's telecommunication system. Additional instruments can augment these measurements in order to leverage observational synergies. Experiments are also offered for the purpose of investigating the atmospheres and surfaces of the satellites.

Xenoliths in maars and diatremes with inferences for the moon, Mars, and Venus.

NASA Technical Reports Server (NTRS)

Mcgetchin, T. R.; Ullrich, G. W.

1973-01-01

Some field observations of the occurrence of deep-seated rock fragments in three terrestrial volcanic features that may have counterparts on the moon or Mars are reviewed, and results of numerical hydrodynamic calculations of the eruption of these types of volcanoes are presented. In particular, the transport of entrained fragmental debris is investigated for the surface (muzzle) velocity of fragments that it yields as a function of fragment size and various values of surface gravity. The implications of these observations and inferences for possible future space missions are examined.

Modern Gemini-Approach to Technology Development for Human Space Exploration

NASA Technical Reports Server (NTRS)

White, Harold

2010-01-01

In NASA's plan to put men on the moon, there were three sequential programs: Mercury, Gemini, and Apollo. The Gemini program was used to develop and integrate the technologies that would be necessary for the Apollo program to successfully put men on the moon. We would like to present an analogous modern approach that leverages legacy ISS hardware designs, and integrates developing new technologies into a flexible architecture This new architecture is scalable, sustainable, and can be used to establish human exploration infrastructure beyond low earth orbit and into deep space.

Triple Asteroid System Triples Asteroid Observers Interest

NASA Image and Video Library

2009-08-06

NASA Deep Space Network, Goldstone radar images show triple asteroid 1994 CC, which consists of a central object approximately 700 meters 2,300 feet in diameter and two smaller moons that orbit the central body. Animation available at the Photojournal

The Role of Cis-Lunar Space in Future Global Space Exploration

NASA Technical Reports Server (NTRS)

Bobskill, Marianne R.; Lupisella, Mark L.

2012-01-01

Cis-lunar space offers affordable near-term opportunities to help pave the way for future global human exploration of deep space, acting as a bridge between present missions and future deep space missions. While missions in cis-lunar space have value unto themselves, they can also play an important role in enabling and reducing risk for future human missions to the Moon, Near-Earth Asteroids (NEAs), Mars, and other deep space destinations. The Cis-Lunar Destination Team of NASA's Human Spaceflight Architecture Team (HAT) has been analyzing cis-lunar destination activities and developing notional missions (or "destination Design Reference Missions" [DRMs]) for cis-lunar locations to inform roadmap and architecture development, transportation and destination elements definition, operations, and strategic knowledge gaps. The cis-lunar domain is defined as that area of deep space under the gravitational influence of the earth-moon system. This includes a set of earth-centered orbital locations in low earth orbit (LEO), geosynchronous earth orbit (GEO), highly elliptical and high earth orbits (HEO), earth-moon libration or "Lagrange" points (E-ML1 through E-ML5, and in particular, E-ML1 and E-ML2), and low lunar orbit (LLO). To help explore this large possibility space, we developed a set of high level cis-lunar mission concepts in the form of a large mission tree, defined primarily by mission duration, pre-deployment, type of mission, and location. The mission tree has provided an overall analytical context and has helped in developing more detailed design reference missions that are then intended to inform capabilities, operations, and architectures. With the mission tree as context, we will describe two destination DRMs to LEO and GEO, based on present human space exploration architectural considerations, as well as our recent work on defining mission activities that could be conducted with an EML1 or EML2 facility, the latter of which will be an emphasis of this paper, motivated in part by recent interest expressed at the Global Exploration Roadmap Stakeholder meeting. This paper will also explore the links between this HAT Cis-Lunar Destination Team analysis and the recently released ISECG Global Exploration Roadmap and other potential international considerations, such as preventing harmful interference to radio astronomy observations in the shielded zone of the moon.

First LOCSMITH locations of deep moonquakes

NASA Astrophysics Data System (ADS)

Hempel, S.; Knapmeyer, M.; Sens-Schönfelder, C.; Oberst, J.

2008-09-01

Introduction Several thousand seismic events were recorded by the Apollo seismic network from 19691977. Different types of events can be distinguished: meteoroid impacts, thermal quakes and internally caused moonquakes. The latter subdivide into shallow (100 to 300km) and deep moonquakes (700 to 1100km), which are by far the most common events. The deep quakes would be no immediate danger to inhabitated stations on the Earth's Moon because of their relatively low magnitude and great depth. However, they bear important information on lunar structure and evolution, and their distribution probably reflects their source mechanism. In this study, we reinvestigate location patterns of deep lunar quakes. LOCSMITH The core of this study is a new location method (LOCSMITH, [1]). This algorithm uses time intervals rather than time instants as input, which contain the dedicated arrival with probability 1. LOCSMITH models and compares theoretical and actual travel times on a global scale and uses an adaptive grid to search source locations compatible with all observations. The output is a set of all possible hypocenters for the considered region of repeating, tidally triggered moonquake activity, called clusters. The shape and size of these sets gives a better estimate of the location uncertainty than the formal standard deviations returned by classical methods. This is used for grading of deep moonquake clusters according to the currently available data quality. Classification of deep moonquakes As first step, we establish a reciprocal dependence of size and shape of LOCSMITH location clouds on number of arrivals. Four different shapes are recognized, listed here in an order corresponding to decreasing spatial resolution: 1. "Balls", which are well defined and relatively small types of sets resembling the commonly assumed error ellipsoid. These are found in the best cases with many observations. Locations in this shape are obtained for clusters 1, 18 or 33, these were already well located by earlier works [2,3]. 2. The next best shape of a location set is the "banana" as found for clusters 5, 39 or 53 [Fig. 1]. In this case, only limited depth resolution is available, and the solution spreads over a large volume. The size of a "banana" could be minimized by either finding a not yet discovered shear wave arrival or estimating a S arrival time interval by considering the coda instead of a clear S arrival. 3. Shape of clouds we call "cones" are formed by clusters for which no compressional wave arrivals, but three S arrivals were picked. Such solutions were found for clusters 35, 201 or 218 [Fig. 2]. A depth limitation is given only by the surface of the Moon's far side. In previous works, locations of these clusters were usually determined with a fixed depth, thus neglecting all depth uncertainty [2]. 4. The fourth and worst class shows a "disc"like shape with no depth resolution and almost no latitude resolution. Clusters of this class, like 4, 23 or 43, were not located so far. From class 1 ("ball") to 4 ("disc") the amount of possible hypocenters increases. So we also found a correlation between size and shape of volumes containing possible hypocenter solutions. Aim We classified all clusters according to the solution set scheme by using arrival times of [2] with an estimated error of ±10s as input for LOCSMITH. We reprocess selected clusters of each class to come up with the special requirements and possibilities of this new location method. As said above, one of the requirements of LOCSMITH is the definition of a time interval instead of a time instant for input, and an interesting option is using an estimated S arrival time interval derived from coda and scattering model, lacking a clear S arrival. We try to find fully automated methods for each processing step, dependent on the quality of data. Methods For despiking we merged methods by [4] and [5] and achieve very good results even for worst case as already presented in [6]. Prior to stacking we developed a complex multiparameter correlation algorithm to calculate the optimum time shift. Results We present relocations of selected deep moonquakes in context of data availability and quality. Previous locations are often contained in our location clouds, but realistic location uncertainties allow large deviations from the best fitting solutions, including locations on the far side of the Moon. Perspective By developing new methods for data processing and using the LOCSMITH locating algorithm we hope to reduce the location uncertainty sufficiently to make sure that all sources are on the near side, or to prove a far side origin of some of them. This would answer questions of hemispheric symmetry of lunar deep seismicity and the Moon's internal structure. References [1] Knapmeyer (2008) accepted to GJI. [2] Nakamura (2005) JGR, 110, E01001. [3] Lognonné (2003) EPSL, 211, 2744. [4] Bulow (2005) JGR, 110, E10003. [5] Sonnemann (2005) EGU05A07960. [6] Hempel, Knapmeyer, Oberst (2008) EGU2008A07989.

Earthquakes drive large-scale submarine canyon development and sediment supply to deep-ocean basins.

PubMed

Mountjoy, Joshu J; Howarth, Jamie D; Orpin, Alan R; Barnes, Philip M; Bowden, David A; Rowden, Ashley A; Schimel, Alexandre C G; Holden, Caroline; Horgan, Huw J; Nodder, Scott D; Patton, Jason R; Lamarche, Geoffroy; Gerstenberger, Matthew; Micallef, Aaron; Pallentin, Arne; Kane, Tim

2018-03-01

Although the global flux of sediment and carbon from land to the coastal ocean is well known, the volume of material that reaches the deep ocean-the ultimate sink-and the mechanisms by which it is transferred are poorly documented. Using a globally unique data set of repeat seafloor measurements and samples, we show that the moment magnitude ( M w ) 7.8 November 2016 Kaikōura earthquake (New Zealand) triggered widespread landslides in a submarine canyon, causing a powerful "canyon flushing" event and turbidity current that traveled >680 km along one of the world's longest deep-sea channels. These observations provide the first quantification of seafloor landscape change and large-scale sediment transport associated with an earthquake-triggered full canyon flushing event. The calculated interevent time of ~140 years indicates a canyon incision rate of 40 mm year -1 , substantially higher than that of most terrestrial rivers, while synchronously transferring large volumes of sediment [850 metric megatons (Mt)] and organic carbon (7 Mt) to the deep ocean. These observations demonstrate that earthquake-triggered canyon flushing is a primary driver of submarine canyon development and material transfer from active continental margins to the deep ocean.

Earthquakes drive large-scale submarine canyon development and sediment supply to deep-ocean basins

PubMed Central

Mountjoy, Joshu J.; Howarth, Jamie D.; Orpin, Alan R.; Barnes, Philip M.; Bowden, David A.; Rowden, Ashley A.; Schimel, Alexandre C. G.; Holden, Caroline; Horgan, Huw J.; Nodder, Scott D.; Patton, Jason R.; Lamarche, Geoffroy; Gerstenberger, Matthew; Micallef, Aaron; Pallentin, Arne; Kane, Tim

2018-01-01

Although the global flux of sediment and carbon from land to the coastal ocean is well known, the volume of material that reaches the deep ocean—the ultimate sink—and the mechanisms by which it is transferred are poorly documented. Using a globally unique data set of repeat seafloor measurements and samples, we show that the moment magnitude (Mw) 7.8 November 2016 Kaikōura earthquake (New Zealand) triggered widespread landslides in a submarine canyon, causing a powerful “canyon flushing” event and turbidity current that traveled >680 km along one of the world’s longest deep-sea channels. These observations provide the first quantification of seafloor landscape change and large-scale sediment transport associated with an earthquake-triggered full canyon flushing event. The calculated interevent time of ~140 years indicates a canyon incision rate of 40 mm year−1, substantially higher than that of most terrestrial rivers, while synchronously transferring large volumes of sediment [850 metric megatons (Mt)] and organic carbon (7 Mt) to the deep ocean. These observations demonstrate that earthquake-triggered canyon flushing is a primary driver of submarine canyon development and material transfer from active continental margins to the deep ocean. PMID:29546245

Moon - False Color Mosaic

NASA Technical Reports Server (NTRS)

1992-01-01

This false-color photograph is a composite of 15 images of the Moon taken through three color filters by Galileo's solid-state imaging system during the spacecraft's passage through the Earth-Moon system on December 8, 1992. When this view was obtained, the spacecraft was 425,000 kilometers (262,000 miles) from the Moon and 69,000 kilometers (43,000 miles) from Earth. The false-color processing used to create this lunar image is helpful for interpreting the surface soil composition. Areas appearing red generally correspond to the lunar highlands, while blue to orange shades indicate the ancient volcanic lava flow of a mare, or lunar sea. Bluer mare areas contain more titanium than do the orange regions. Mare Tranquillitatis, seen as a deep blue patch on the right, is richer in titanium than Mare Serenitatis, a slightly smaller circular area immediately adjacent to the upper left of Mare Tranquillitatis. Blue and orange areas covering much of the left side of the Moon in this view represent many separate lava flows in Oceanus Procellarum. The small purple areas found near the center are pyroclastic deposits formed by explosive volcanic eruptions. The fresh crater Tycho, with a diameter of 85 kilometers (53 miles), is prominent at the bottom of the photograph, where part of the Moon's disk is missing.

The deep Earth may not be cooling down

NASA Astrophysics Data System (ADS)

Andrault, Denis; Monteux, Julien; Le Bars, Michael; Samuel, Henri

2016-06-01

The Earth is a thermal engine generating the fundamental processes of geomagnetic field, plate tectonics and volcanism. Large amounts of heat are permanently lost at the surface yielding the classic view of the deep Earth continuously cooling down. Contrary to this conventional depiction, we propose that the temperature profile in the deep Earth has remained almost constant for the last ∼4.3 billion years. The core-mantle boundary (CMB) has reached a temperature of ∼4400 K in probably less than 1 million years after the Moon-forming impact, regardless the initial core temperature. This temperature corresponds to an abrupt increase in mantle viscosity atop the CMB, when ∼60% of partial crystallization was achieved, accompanied with a major decrease in heat flow at the CMB. Then, the deep Earth underwent a very slow cooling until it reached ∼4100 K today. This temperature at, or just below, the mantle solidus is suggested by seismological evidence of ultra-low velocity zones in the D;-layer. Such a steady thermal state of the CMB temperature excludes thermal buoyancy from being the predominant mechanism to power the geodynamo over geological time. An alternative mechanism to sustain the geodynamo is mechanical forcing by tidal distortion and planetary precession. Motions in the outer core are generated by the conversion of gravitational and rotational energies of the Earth-Moon-Sun system. Mechanical forcing remains efficient to drive the geodynamo even for a sub-adiabatic temperature gradient in the outer core. Our thermal model of the deep Earth is compatible with an average CMB heat flow of 3.0 to 4.7 TW. Furthermore, the regime of core instabilities and/or secular changes in the astronomical forces could have supplied the lowermost mantle with a heat source of variable intensity through geological time. Episodic release of large amounts of heat could have remelted the lowermost mantle, thereby inducing the dramatic volcanic events that occurred during the Earth's history. In this scenario, because the Moon is a necessary ingredient to sustain the magnetic field, the habitability on Earth appears to require the existence of a large satellite.

7.3 Communications and Navigation

NASA Technical Reports Server (NTRS)

Manning, Rob

2005-01-01

This presentation gives an overview of the networks NASA currently uses to support space communications and navigation, and the requirements for supporting future deep space missions, including manned lunar and Mars missions. The presentation addresses the Space Network, Deep Space Network, and Ground Network, why new support systems are needed, and the potential for catastrophic failure of aging antennas. Space communications and navigation are considered during Aerocapture, Entry, Descent and Landing (AEDL) only in order to precisely position, track and interact with the spacecraft at its destination (moon, Mars and Earth return) arrival. The presentation recommends a combined optical/radio frequency strategy for deep space communications.

Imaging the Moon's Core with Seismology

NASA Technical Reports Server (NTRS)

Weber, Renee C.; Lin, Pei-Ying Patty; Garnero, Ed J.; Williams, Quetin C.; Lognonne, Philippe

2011-01-01

Constraining the structure of the lunar core is necessary to improve our understanding of the present-day thermal structure of the interior and the history of a lunar dynamo, as well as the origin and thermal and compositional evolution of the Moon. We analyze Apollo deep moonquake seismograms using terrestrial array processing methods to search for the presence of reflected and converted energy from the lunar core. Although moonquake fault parameters are not constrained, we first explore a suite of theoretical focal spheres to verify that fault planes exist that can produce favorable core reflection amplitudes relative to direct up-going energy at the Apollo stations. Beginning with stacks of event seismograms from the known distribution of deep moonquake clusters, we apply a polarization filter to account for the effects of seismic scattering that (a) partitions energy away from expected components of ground motion, and (b) obscures all but the main P- and S-wave arrivals. The filtered traces are then shifted to the predicted arrival time of a core phase (e.g. PcP) and stacked to enhance subtle arrivals associated with the Moon s core. This combination of filtering and array processing is well suited for detecting deep lunar seismic reflections, since we do not expect scattered wave energy from near surface (or deeper) structure recorded at varying epicentral distances and stations from varying moonquakes at varying depths to stack coherently. Our results indicate the presence of a solid inner and fluid outer core, overlain by a partial-melt-containing boundary layer (Table 1). These layers are consistently observed among stacks from four classes of reflections: P-to-P, S-to-P, P-to-S, and S-to-S, and are consistent with current indirect geophysical estimates of core and deep mantle properties, including mass, moment of inertia, lunar laser ranging, and electromagnetic induction. Future refinements are expected following the successful launch of the GRAIL lunar orbiter and SELENE 2 lunar lander missions.

New Inquiry into Distribution and Mechanism of Deep Moonquakes with Recently Identified Seismic Events

NASA Technical Reports Server (NTRS)

Nakamura, Yosio

2005-01-01

The objectives of the project were (1) to complete our preceding effort, supported by NASA grant NAGS-1 1619, of searching for deep moonquakes in the far hemisphere of the Moon among the seismic events detected by the Apollo seismic array; and (2) to re-examine the distribution and mechanism of deep moonquakes in the light of the newly identified deep moonquakes. The project was originally planned for completion in three years, of which only the first year, covered by this report, was funded. As a result, we were able to address only the first objective during the period, and the major part of the second objective was left for the future.

In-Situ Environmental Monitoring and Science Investigations Enabled by the Deep Space Gateway

NASA Astrophysics Data System (ADS)

Clark, P. E.; Collier, M. R.; Farrell, W. M.

2018-02-01

A distributed network of instrument packages in an ARTEMIS-like orbit will serve as the much-needed basis for on-going monitoring of cislunar environmental dynamics, critical for a successful human presence on the Moon.

Folds on Europa: implications for crustal cycling and accommodation of extension.

PubMed

Prockter, L M; Pappalardo, R T

2000-08-11

Regional-scale undulations with associated small-scale secondary structures are inferred to be folds on Jupiter's moon Europa. Formation is consistent with stresses from tidal deformation, potentially triggering compressional instability of a region of locally high thermal gradient. Folds may compensate for extension elsewhere on Europa and then relax away over time.

The last stage of Earth's formation: Increasing the pressure

NASA Astrophysics Data System (ADS)

Lock, S. J.; Stewart, S. T.; Mukhopadhyay, S.

2017-12-01

A range of high-energy, high-angular momentum (AM) giant impacts have been proposed as a potential trigger for lunar origin. High-energy, high-AM collisions create a previously unrecognized planetary object, called a synestia. Terrestrial synestias exceed the corotation limit for a rocky planet, forming an extended structure with a corotating inner region and disk-like outer region. We demonstrate that the internal pressures of Earth-like planets do not increase monotonically during the giant impact stage, but can vary substantially in response to changes in rotation and thermal state. The internal pressures in an impact-generated synestia are much lower than in condensed, slowly rotating planets of the same mass. For example, the core-mantle boundary (CMB) pressure can be as low as 60 GPa for a synestia with Earth mass and composition, compared to 136 GPa in the present-day Earth. The lower pressures are due to the low density and rapid rotation of the post-impact structure. After a high-AM Moon-forming impact, the internal pressures in the interior of the synestia would have increased to present-day Earth values in two stages: first by vapor condensation and second by removal of AM from the Earth during the tidal evolution of the Moon. The pressure evolution of the Earth has several implications. Metal-silicate equilibration after the impact would have occurred at much lower pressures than has previously been assumed. The observed moderately siderophile element abundances in the mantle may be consistent with equilibration at the bottom of a deep, lower-pressure magma ocean. In addition, the pressure at the CMB during cooling is coincident with, or lower than, the proposed intersection of liquid adiabats with the mantle liquidus. The mantle would hence freeze from the bottom up and there would be no basal magma ocean. The subsequent pressure increase and tidal heating due to the Moon's orbital evolution likely induces melting in the lowermost mantle. Increasing pressure in the upper mantle also leads to exothermic and endothermic phase changes potentially producing partial melts in the mid-mantle. High-pressure partial melts could produce precursor material for the seismically and chemically anomalous regions that are observed in the lower mantle today.

Volatiles in the Earth and Moon: Constraints on planetary formation and evolution

NASA Astrophysics Data System (ADS)

Parai, Rita

The volatile inventories of the Earth and Moon reflect unique histories of volatile acquisition and loss in the early Solar System. The terrestrial volatile inventory was established after the giant impact phase of accretion, and the planet subsequently settled into a regime of long-term volatile exchange between the mantle and surface reservoirs in association with plate tectonics. Therefore, volatiles in the Earth and Moon shed light on a diverse array of processes that shaped planetary bodies in the Solar System as they evolved to their present-day states. Here we investigate new constraints on volatile depletion in the early Solar System, early outgassing of the terrestrial mantle, and the long-term evolution of the deep Earth volatile budget. We develop a Monte Carlo model of long-term water exchange between the mantle and surface reservoirs. Previous estimates of the deep Earth return flux of water are up to an order of magnitude too large, and incorporation of recycled slabs on average rehydrates the upper mantle but dehydrates the plume source. We find evidence for heterogeneous recycling of atmospheric argon and xenon into the upper mantle from noble gases in Southwest Indian Ridge basalts. Xenon isotope systematics indicate that xenon budgets of mid-ocean ridge and plume-related mantle sources are dominated by recycled atmospheric xenon, though the two sources have experienced different degrees of degassing. Differences between the mid-ocean ridge and plume sources were initiated within the first 100 million years of Earth history, and the two sources have never subsequently been homogenized. New high-precision xenon isotopic data contribute to an emerging portrait of two mantle reservoirs with distinct histories of outgassing and incorporation of recycled material in association with plate tectonics. Xenon isotopes indicate that the Moon likely formed within ˜70 million years of the start of the Solar System. To further investigate early Solar System chronology, we determined strontium isotopic compositions in a suite of planetary materials. If the Moon is derived from proto-Earth material, then rubidium-strontium systematics in the lunar anorthosite 60025 and Moore County plagioclase indicate that Moon formation occurred within ~62 million years of the start of the Solar System.

Cryogenic Selective Surfaces

NASA Technical Reports Server (NTRS)

Youngquist, Robert C.; Nurge, Mark A.

2015-01-01

Under our NASA Innovative Advanced Concepts (NIAC) project we have theoretically demonstrated a novel selective surface that reflects roughly 100 times more solar radiation than any other known coating. If this prediction holds up under experimental tests it will allow cryogenic temperatures to be reached in deep space even in the presence of the sun. It may allow LOX to be carried to the Moon and Mars. It may allow superconductors to be used in deep space without a refrigeration system.

Dynamic triggering of deep earthquakes within a fossil slab

NASA Astrophysics Data System (ADS)

Cai, Chen; Wiens, Douglas A.

2016-09-01

The 9 November 2009 Mw 7.3 Fiji deep earthquake is the largest event in a region west of the Tonga slab defined by scattered seismicity and velocity anomalies. The main shock rupture was compact, but the aftershocks were distributed along a linear feature at distances of up to 126 km. The aftershocks and some background seismicity define a sharp northern boundary to the zone of outboard earthquakes, extending westward toward the Vitiaz deep earthquake cluster. The northern earthquake lineament is geometrically similar to tectonic reconstructions of the relict Vitiaz subduction zone at 8-10 Ma, suggesting the earthquakes are occurring in the final portion of the slab subducted at the now inactive Vitiaz trench. A Coulomb stress change calculation suggests many of the aftershocks were dynamically triggered. We propose that fossil slabs contain material that is too warm for earthquake nucleation but may be near the critical stress susceptible to dynamic triggering.

Ionospheric Bow Wave Induced by the Moon Shadow Ship Over the Continent of United States on 21 August 2017

NASA Astrophysics Data System (ADS)

Sun, Yang-Yi; Liu, Jann-Yenq; Lin, Charles Chien-Hung; Lin, Chi-Yen; Shen, Ming-Hsueh; Chen, Chieh-Hung; Chen, Chia-Hung; Chou, Min-Yang

2018-01-01

A moon shadow of the total solar eclipse swept through the continent of United States (CONUS) from west to east on 21 August 2017. Massive total electron content (integration of electron density from 0 km to 20,200 km altitude) observations from 2,255 ground-based Global Navigation Satellite System receivers show that the moon shadow ship generates a great ionospheric bow wave front which extends 1,500 km away from the totality path covering the entire CONUS. The bow wave front consists of the acoustic shock wave due to the supersonic/near-supersonic moon shadow ship and the significant plasma recombination due to the reduction in solar irradiation within the shadow area. The deep bow wave trough (-0.02 total electron content unit (1 TECU = 1016 el m-2) area) nearly coincides with the 100% obscuration moving along the totality path over the CONUS through the entire eclipse period. The supersonic moon shadow ship induces a bow wave crest in front of the ship ( 80% obscuration). It is the first time to find the acoustic shock wave-formed bow wave trough and crest near the totality.

The earliest Lunar Magma Ocean differentiation recorded in Fe isotopes

NASA Astrophysics Data System (ADS)

Wang, Kun; Jacobsen, Stein B.; Sedaghatpour, Fatemeh; Chen, Heng; Korotev, Randy L.

2015-11-01

Recent high-precision isotopic measurements show that the isotopic similarity of Earth and Moon is unique among all known planetary bodies in our Solar System. These observations provide fundamental constraints on the origin of Earth-Moon system, likely a catastrophic Giant Impact event. However, in contrast to the isotopic composition of many elements (e.g., O, Mg, Si, K, Ti, Cr, and W), the Fe isotopic compositions of all lunar samples are significantly different from those of the bulk silicate Earth. Such a global Fe isotopic difference between the Moon and Earth provides an important constraint on the lunar formation - such as the amount of Fe evaporation as a result of a Giant Impact origin of the Moon. Here, we show through high-precision Fe isotopic measurements of one of the oldest lunar rocks (4.51 ± 0.10 Gyr dunite 72 415), compared with Fe isotope results of other lunar samples from the Apollo program, and lunar meteorites, that the lunar dunite is enriched in light Fe isotopes, complementing the heavy Fe isotope enrichment in other lunar samples. Thus, the earliest olivine accumulation in the Lunar Magma Ocean may have been enriched in light Fe isotopes. This new observation allows the Fe isotopic composition of the bulk silicate Moon to be identical to that of the bulk silicate Earth, by balancing light Fe in the deep Moon with heavy Fe in the shallow Moon rather than the Moon having a heavier Fe isotope composition than Earth as a result of Giant Impact vaporization.

Observation of the shadowing of cosmic rays by the Moon using a deep underground detector

NASA Astrophysics Data System (ADS)

Ambrosio, M.; Antolini, R.; Aramo, C.; Auriemma, G.; Baldini, A.; Barbarino, G. C.; Barish, B. C.; Battistoni, G.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bisi, V.; Bloise, C.; Bower, C.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Carboni, M.; Castellano, M.; Cecchini, S.; Cei, F.; Chiarella, V.; Choudhary, B. C.; Coutu, S.; de Benedictis, L.; de Cataldo, G.; Dekhissi, H.; de Marzo, C.; de Mitri, I.; Derkaoui, J.; de Vincenzi, M.; di Credico, A.; Erriquez, O.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Giorgini, M.; Grassi, M.; Gray, L.; Grillo, A.; Guarino, F.; Guarnaccia, P.; Gustavino, C.; Habig, A.; Hanson, K.; Heinz, R.; Huang, Y.; Iarocci, E.; Katsavounidis, E.; Kearns, E.; Kim, H.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D. S.; Lipari, P.; Longley, N. P.; Longo, M. J.; Maaroufi, F.; Mancarella, G.; Mandrioli, G.; Manzoor, S.; Neri, A. Margiotta; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M. N.; Mazzotta, C.; Michael, D. G.; Mikheyev, S.; Miller, L.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicoló, D.; Orth, C.; Osteria, G.; Ouchrif, M.; Palamara, O.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C. W.; Petrera, S.; Pistilli, P.; Popa, V.; Pugliese, V.; Rainò, A.; Reynoldson, J.; Ronga, F.; Rubizzo, U.; Satriano, C.; Satta, L.; Scapparone, E.; Scholberg, K.; Sciubba, A.; Serra-Lugaresi, P.; Severi, M.; Sioli, M.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J. L.; Sulak, L. R.; Surdo, A.; Tarlè, G.; Togo, V.; Ugolotti, D.; Vakili, M.; Walter, C. W.; Webb, R.

1999-01-01

Using data collected by the MACRO experiment during the years 1989-1996, we show evidence for the shadow of the Moon in the underground cosmic ray flux with a significance of 3.6σ. This detection of the shadowing effect is the first by an underground detector. A maximum-likelihood analysis is used to determine that the angular resolution of the apparatus is 0.9°+/-0.3°. These results demonstrate MACRO's capabilities as a muon telescope by confirming its absolute pointing ability and quantifying its angular resolution.

The exploration about the means of lunar-landing based on space-launch

NASA Astrophysics Data System (ADS)

Yi, Jiang; Zheming, Zhang; Debin, Fu

The lunar exploration and lunar-landing is the first step of china s deep space exploration On the basement of our country s achievements and the experiences of the foreign countries the paper brings forward the idea that use the existing transportation technology to sent the Launch vehicles and cosmonauts to the near-earth orbit in batches assemble the components together on the Space-launch Platform and then launch them to the Moon to fulfill our dream of manned landing on the moon The paper also discusses the Space-launch Platform and the launching way

The effects of magmatic redistribution of heat producing elements on the lunar mantle evolution inferred from numerical models that start from various initial states

NASA Astrophysics Data System (ADS)

Ogawa, Masaki

2018-02-01

To discuss how redistribution of heat producing elements (HPEs) by magmatism affects the lunar mantle evolution depending on the initial condition, I present two-dimensional numerical models of magmatism in convecting mantle internally heated by incompatible HPEs. Mantle convection occurs beneath a stagnant lithosphere that inhibits recycling of the HPE-enriched crustal materials to the mantle. Magmatism is modeled by a permeable flow of magma generated by decompression melting through matrix. Migrating magma transports heat, mass, and HPEs. When the deep mantle is initially hot with the temperature TD around 1800 K at its base, magmatism starts from the beginning of the calculated history to extract HPEs from the mantle. The mantle is monotonously cooled, and magmatism ceases within 2 Gyr, accordingly. When the deep mantle is initially colder with TD around 1100 K, HPEs stay in the deep mantle for a longer time to let the planet be first heated up and then cooled only slightly. If, in addition, there is an HPE-enriched domain in the shallow mantle at the beginning of the calculation, magma continues ascending to the surface through the domain for more than 3 Gyr. The low TD models fit in with the thermal and magmatic history of the Moon inferred from spacecraft observations, although it is not clear if the models are consistent with the current understanding of the origin of the Moon and its magnetic field. Redistribution of HPEs by magmatism is a crucial factor that must be taken into account in future studies of the evolution of the Moon.

Lunar Sample Return Missions Using a Tele-Robotic Lander

NASA Astrophysics Data System (ADS)

Downes, H.; Crawford, I. A.; Alexander, L.

2018-02-01

Deep Space Gateway would allow tele-robotic landers and rovers to access regions of the Moon which have not been previously sampled. Scientific questions, e.g., the nature and duration of volcanic activity and the composition of the mantle/lower crust, could be addressed.

Protecting the Moon for research: ILEWG report

NASA Astrophysics Data System (ADS)

Foing, Bernard H.

We give a report on recommendations with emphasis on environment protection, and since last COSPAR from ILEWG International conferences Exploration and Utilisation of the Moon on held at Cape Canaveral in 2008 (ICEUM10), and in Beijing in May 2010 with IAF (GLUC -ICEUM11). We discuss the different rationale for Moon exploration, as debated at ILEWG. ILEWG Science task group has listed priorities for scientific investigations: clues on the formation and evolution of rocky planets, accretion and bombardment in the inner solar system, comparative planetology processes (tectonic, volcanic, impact cratering, volatile delivery), records astrobiology, survival of organics; past, present and future life; sciences from a biology lunar laboratory. We discuss how to preserve Moon research potential in these areas while operating with instruments, landers, rover during a cooperative robotic village, and during the transition form lunar human outpost to permanent sustainable human base. We discuss how Moon-Mars Exploration can inspire solutions to global Earth sustained development with the trade-off of In-Situ Utilisation of resources; Establishment of permanent robotic infrastructures, Environmental and planetary protection aspects and lessons for Mars; Life sciences laboratories, and support to human exploration. Co-authors: ILEWG Task Groups on Science, Technology and Human Lunar Bases ILEWG Reference documents: http://sci.esa.int/ilewg -10th ILEWG Conference on Exploration and Utilisation of the Moon, NASA Lunar Ex-ploration Analysis Group-PSace Resources Roundtable, Cape Canaveral October 2008, pro-gramme online at http://sci.esa.int/ilewg/ -9th ILEWG Conference on Exploration and Utilisation of the Moon, ICEUM9 Sorrento 2007, programme online at http://sci.esa.int/ilewg/ -8th ILEWG Conference on Exploration and Utilisation of the Moon, Beijing July 2006, programme online at http://sci.esa.int/ilewg/ -The Moon and Near Earth Objects (P. Ehrenfreund , B.H. Foing, A. Cellino Editors), Ad-vances in Space Research, Volume 37, Issue 1, pp 1-192, 2006 -7th ILEWG Conference on Exploration and Utilisation of the Moon, Toronto Sept 2005, Programme and Proceedings on line at www.ilewg.org, R. Richards et al Editors -6th ILEWG Conference on Exploration and Utilisation of the Moon, Udaipur Nov. 2004, Proceedings ( N. Bhandari Editor), Journal Earth System Science, India, 114, No6, Dec 2005, pp. 573-841 -5th ILEWG Conference on Exploration and Utilisation of the Moon, Hawaii Nov 2003, Pro-ceedings ILC2005/ICEUM5 (S.M. Durst et al Editors), Vol 108, 1-576 pp, Science and Tech-nology Series, American Astronautical Society, 2004 -'The next steps in exploring deep space -A cosmic study by the IAA', W. Huntress, D. Stetson, R. Farquhar, J. Zimmerman, B. Clark, W. O'Neil, R. Bourke and B. Foing, Acta Astronautica, Vol 58, Issues 6-7, March-April 2006, p302-377 -IAA/ESA workshop on "Next Steps in Exploring Deep Space", ESTEC 22-23 sept. 2003 (B.H. Foing W. Huntress, conveners) Lunar Exploration, Planetary and Space Science, Vol 50, issue 14-15, Dec 2002 (B.H. Foing al) -ESLAB36 symposium on "Earth-like Planets and Moons", 2002, ESA-SP514, pp. 1-356, (B.H.Foing B. Battrick, editors) -'Lunar Exploration 2000', (B.H. Foing, D. Heather, Editors), Adv. Space Research Vol 30, Nr 8, 2002 -'Earth-Moon Relationships', Proceedings of the Conference held in Padova, Italy at the Ac-cademia Galileiana di Scienze Lettere ed Arti, Nov. 2000, (C. Barbieri and F. Rampazzi, Editors), in Earth, Moon , Planets Vol. 85-86, Nos 1-3, pp 1-575, 2001 -4th International Conference on Exploration and Utilisation of the Moon, ESTEC, 2000, ESA SP-462 (B.H. Foing M. Perry, editors) -Investing in Space: The Challenge for Europe. Long-Term Space Policy Committee, Second Report, May 1999. ESA-SP-2000 -2nd International Lunar Workshop, held at Kyoto in October 1996, Proceedings, H. Mizutani, editor, Japan Space Forum Publisher, 1997 International Lunar Workshop, 1994 May 31-June 3, Beatenberg, Switzerland. Proceedings. Ed. Balsiger, H. et al. European Space Agency, 1994. ESA-SP-1170 -Astronomy and Space Science from the Moon', Proceedings of COSPAR/IAF session at World Congress, Washington, (B.H. Foing et al editors), Advances in Space Research, Volume 14, Issue 6, 1994 -Mission to the Moon, Europe's Priorities for Scientific Exploration and Utilisation of the Moon', R.M. Bonnet et al, European Space Agency, ESA SP-1150, June 1992

DEEP-South: Preliminary Photometric Results from the KMTNet-CTIO

NASA Astrophysics Data System (ADS)

Kim, Myung-Jin; Moon, Hong-Kyu; Choi, Young-Jun; Yim, Hong-Suh; Bae, Young-Ho; Roh, Dong-Goo; Park, Jin Tae; Moon, Bora

2016-01-01

Korea Astronomy and Space Science Institute (KASI) successfully completed the development of Korea Microlensing Telescope Network (KMTNet, Park et al. 2012) in mid-2015, following which it conducted test runs for several months. `DEep Ecliptic Patrol of the Southern sky' (DEEP-South, Moon et al. 2015), which will be used for asteroid and comet studies, will not only characterize targeted asteroids, carrying out blind surveys toward the sweet spots, but will also mine the data of such bodies using the KMTNet archive. We report preliminary lightcurves of four Potentially Hazardous Asteroids (PHAs) from test runs at KMTNet-CTIO in the February - May 2015 period.

Early History of the Moon: Zircon Perspective

NASA Technical Reports Server (NTRS)

Grange, M.L.; Nemchin, A.A.; Pidgeon, R.T.; Meyer, C.

2009-01-01

The Moon is believed to have formed from debris produced by a giant impact of a Mars sized body with the Earth (at around 4.51 Ga), forming a primitive body with a thick global layer of melt referred to as the Lunar Magma Ocean (LMO). The crystallization of LMO created internal stratification of the Moon forming main geochemical reservoirs. The surface features on the Moon were shaped by the subsequent collision with several large impactors during a short period of time (3.9-4.0 Ga). This process known as the Late Heavy Bombardment is supported by models of planetary motion, suggesting that rapid migration of giant planets could have triggered a massive delivery of planetesimals from the asteroid belt into the inner Solar System at about 3.9 Ga. Although, general chronology of LMO and LHB is well established using both long lived (U-Pb, Rb-Sr, Sm-147-Nd-143 and Ar-Ar) and extinct (Hf-182-W-182 and 146Sm-142Nd) isotope systems, some of these systems such as Ar-Ar are known to reset easily during secondary thermal overprints. As a result important details in the timing of LMO and LHB remain unresolved. In addition, the relative weakness of these systems under high T conditions can potentially bias the chronological information towards later events in the history of the Moon.

Can tides influence volcanic eruptions?

NASA Astrophysics Data System (ADS)

Girona, T.; Huber, C.

2015-12-01

The possibility that the Moon-Sun gravitational force can affect terrestrial volcanoes and trigger eruptions is a controversial issue that has been proposed since ancient times, and that has been widely debated during the last century. The controversy arises mainly from two reasons. First, the days of initiation of eruptions are not well known for many volcanoes, and thus a robust statistical comparison with tidal cycles cannot be performed for many of them. Second, the stress changes induced by tides in the upper crust are very small (10-3 MPa) compared to the tensile strength of rocks (~ 10-1-10 MPa), and hence the mechanism by which tidal stresses might trigger eruptions is unclear. In this study, we address these issues for persistently degassing volcanoes, as they erupt frequently and thus the initiation time of a significant number of eruptions (>30) is well known in several cases (9). In particular, we find that the occurrence of eruptions within ±2 days from neap tides (first and third quarter moon) is lower than 34% (e.g., 29% for Etna, Italy; 28% for Merapi, Indonesia), which is the value expected if eruptions occur randomly with no external influence. To understand this preference for erupting far away from neap tides, we have developed a new lumped-parameter model that accounts for the deformation of magma reservoirs, a partially open conduit, and a gas layer where bubbles accumulate beneath volcanic craters before being released. We demonstrate that this system reservoir-conduit-gas layer acts as an amplifier of the tidal stresses, such that, when a volcano approaches to a critical state, the gas overpressure beneath the crater can reach up to several MPa more during a spring tide (full and new moon) than during a neap tide. This amplification mechanism can explain why active volcanoes are sensitive to the moon cycles.

KSC-2014-3217

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, a crowd turns out for a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

The Delivery of Water to the Lunar Mantle by Late Planetesimal Accretion (Invited)

NASA Astrophysics Data System (ADS)

Bottke, W. F.; Walker, R. J.; Day, J.; Nesvorny, D.; Elkins-Tanton, L. T.

2010-12-01

The final stages of planet formation in the inner Solar System are thought to have culminated in enormous planetary collisions, such as the hypothesized ‘giant impact’ origin for the Earth and Moon that occurred ~50-100 My after the formation of the first Solar System solids. The giant impact event probably triggered a final phase of core formation on these worlds, with global magma oceans effectively stripping the terrestrial and lunar mantles of highly siderophile elements (HSE; Re, Os, Ir, Ru, Pt, Rh, Pd, Au), which have extremely high metal-silicate partition coefficients. Studies of mantle-derived terrestrial peridotites and derivative lunar mantle melts, however, show that the terrestrial and lunar mantles have elevated absolute, and approximately chondritic relative abundances of highly siderophile elements (HSE). We argue this material was most likely delivered by continued planetesimal accretion via HSE-rich impactors within tens of My of core formation termination, with subsequently-accreted materials mixed into each mantle by convection. This process, often called the “late veneer” but here termed late accretion, delivered > 0.4% Earth masses to the terrestrial mantle and produced an Earth/Moon mass input ratio of ~1,000. Using Monte Carlo models, we found that this high ratio most likely came from planetesimal populations dominated by massive impactors. Specifically, if the late accretion population had the form dN ∝ D-q dD (i.e., dN is the number of planetesimals of diameter D within bin dD), the power law index of the projectiles was q < 2 for 200 < D < 4000 km. Interestingly, q ~ 2 populations are also found in planetesimal size distributions derived from evidence taken near 1 AU (e.g., D > 250 km asteroids in the inner/central main belt with semimajor axis < 2.8 AU, the population of non-saturated ancient martian impact basins with 700 < D < 2000 km) as well as from new planetary accretion models that allow planetesimals to be “born big” via turbulent concentration mechanisms in the gas disk. Using a q ~ 2 size distribution and HSE constraints, we predict the largest late accretion impactors to strike the Earth and Moon, on average, were D = 2,500-3,000 km and 250-300 km, respectively. If true, it is possible that the same projectile that delivered most of the Moon's HSE may have also have provided it with water. The Moon's interior was once thought to be largely dry, with bulk water estimates of less than 1 part per billion (ppb). New sample measurements, however, suggest the water content in the lunar mantle is between 200 and several thousand ppb. Assuming that our inferred D = 250-300 km lunar projectile could reach and mix itself into a spherical shell that is 100 to 500 km deep within the Moon, and that the projectile had a minimum bulk water content of 0.05-0.2 wt% (i.e., conservative values similar to those measured from “dry rocks” like ordinary and enstatite chondrites), we estimate that 400-3000 ppb water could be delivered to the lunar interior by late accretion. This finding could help sidestep a difficult problem, namely explaining how the water in the lunar mantle could migrate from a “wet” primordial Earth to a growing Moon through a very hot and largely vaporized protolunar disk.

Seismic effects from major basin formation on the Moon and Mercury

NASA Technical Reports Server (NTRS)

Schultz, P. H.; Gault, D. E.

1974-01-01

Grooved and hilly terrains are reported which occur at the antipode of major basins on the Moon (Imbrium, Orientale) and Mercury (Caloris). Order-of-magnitude calculations, for an Imbrium-size impact on the Moon, indicate P-wave-induced surface displacements of 10 m at the basin antipode that would arrive prior to secondary ejecta. Comparable surface waves are reported which would arrive subsequent to secondary ejecta impacts and would increase in magnitude as they converge at the antipode. Other seismically induced surface features include: subdued, furrowed crater walls produced by landslides and concomitant secondary impacts; emplacement and leveling of light plains units owing to seismically induced "fluidization" of slide material; knobby, pitted terrain around old basins from enhancement of seismic waves in ancient ejecta blankets; and the production and enhancement of deep-seated fractures that led to the concentration of farside lunar maria in the Apollo-Ingenii region.

Ares V: Progress Towards a Heavy Lift Capability for the Moon and Beyond

NASA Technical Reports Server (NTRS)

Creech, Steve

2008-01-01

NASA's new exploration initiative will again take humans beyond low Earth orbit, to the moon, and into deep space. The space agency is developing a new fleet of launch vehicles that will fulfill the national goals of replacing the Space Shuttle fleet, completing the International Space Station, establishing a permanent outpost on the moon, and eventually traveling to Mars. Separate crew and cargo vehicles emerged from mission architecture studies - the Ares I to carry the Orion crew exploration vehicle and its crew of4 to 6 astronauts, and the Ares V to carry the Altair lunar lander or other supplies to support future exploration missions. (Figure 1) These vehicles will be designed to be safe, affordable, sustainable, reliable, operable with the safety, reliability, flexibility, and operability to serve this nation's manned and unmanned exploration programs for the coming decades. This paper discusses recent and current progress on the Ares V and planned future activities.

Moon Dust may Simulate Vascular Hazards of Urban Pollution

NASA Astrophysics Data System (ADS)

Rowe, W. J.

A long duration mission to the moon presents several potential cardiovascular complications. To the risks of microgravity and hypokinesia, and the fact that pharmaceuticals cannot be always depended upon in the space fight conditions, there is a possible additional risk due to inhalation in the lunar module of ultra-fine dust (<100 nm). This may trigger endothelial dysfunction by mechanisms similar to those shown to precipitate endothelial insults complicating ultra-fine urban dust exposure. Vascular constriction and a significant increase in diastolic blood pressures have been found in subjects inhaling urban dust within just two hours, possibly triggered by oxidative stress, inflammatory effects, and calcium overload with a potential magnesium ion deficit playing an important contributing role. Both Irwin and Scott on Apollo 15, experienced arrhythmias, and in Irwin's case associated with syncope and severe dyspnea with angina during reentry. After the mission both had impairment in cardiac function, and delay in cardiovascular recovery, with Irwin in addition having stress test- induced extremely high blood pressures, with no available stress test results in Scott's case for comparison. It is conceivable that the chemical nature or particle size of the lunar dust is sufficiently variable to account for these complications, which were not described on the other Apollo missions. This could be determined by non-invasive endothelial-dependent flow-mediated dilatation studies in the lunar environment at various sites, thereby determining the site with the least endothelial vulnerability to dysfunction. These studies could be used also to demonstrate possible intensification of endothelial dysfunction from inhalation of ultra-fine moon dust in the lunar module.

New Active Remote-sensing Capabilities: Laser Ablation Spectrometer and Lidar Atmospheric Species Profile Measurements

NASA Technical Reports Server (NTRS)

DeYoung, R. J.; Bergstralh, J. T.

2005-01-01

Introduction: With the anticipated development of high-capacity fission power and electric propulsion for deep-space missions, it will become possible to propose experiments that demand higher power than current technologies (e.g. radioisotope power sources) provide. Jupiter Icy Moons Orbiter (JIMO), the first mission in the Project Prometheus program, will explore the icy moons of Jupiter with a suite of high-capability experiments that take advantage of the high power levels (and indirectly, the high data rates) that fission power affords. This abstract describes two high-capability active-remote-sensing experiments that will be logical candidates for subsequent Prometheus-class missions.

In-Space Propulsion Engine Architecture Based on Sublimation of Planetary Resources: From Exploration Robots to NED Mitigation

NASA Technical Reports Server (NTRS)

Sibille, Laurent; Mantovani, James; Dominquez, Jesus

2011-01-01

The purpose of this NIAC study is to identify those volatile and mineral resources that are available on asteroids, comets, moons and planets in the solar system, and investigate methods to transform these resources into forms of power that will expand the capabilities of future robotic and human exploration missions to explore planetary bodies beyond the Moon and will mitigate hazards from NEOs. The sources of power used for deep space probe missions are usually derived from either solar panels for electrical energy, radioisotope thermal generators for thermal energy, or fuel cells and chemical reactions for chemical energy and propulsion.

Ocean science. Enhanced: internal tides and ocean mixing.

PubMed

Garrett, Chris

2003-09-26

Recent satellite and in situ observations have shown that at ocean ridges and other seafloor topographic features, a substantial amount of energy is transferred from the main ocean tides into "internal tides." In his Perspective, Garrett explains how these internal waves with tidal periods propagate through the density-stratified deep ocean and eventually break down into turbulence. The resulting mixing affects ocean stratification and ocean circulation. It thus influences climate as well as biological production. The energy for the internal tides is derived from the rotational energy of the Earth-Moon system changes of the length of the day and the distance to the Moon.

Hard X-ray (greater than 10 keV) telescope for space astronomy from the Moon

NASA Astrophysics Data System (ADS)

Frontera, F.; de Chiara, P.; Pasqualini, G.

1994-06-01

The use of the Moon as site for deep observations of astrophysical sources in hard X-rays (greater than 10 keV) is very exciting, in spite of several technological problems to be solved. A strong limitation to the sensitivity of hard X-ray experiments is imposed by the use of direct-viewing (with or without masks) detectors. We propose a lunar hard X-ray observatory, (LHEXO), that makes use of a hard X-ray concentrator which is based on the use of confocal paraboloidal mirrors made of mosaic crystals of graphite (002). In this paper we describe telescope concept and its expected performances.

Volatile accretion history of the terrestrial planets and dynamic implications.

PubMed

Albarède, Francis

2009-10-29

Accretion left the terrestrial planets depleted in volatile components. Here I examine evidence for the hypothesis that the Moon and the Earth were essentially dry immediately after the formation of the Moon-by a giant impact on the proto-Earth-and only much later gained volatiles through accretion of wet material delivered from beyond the asteroid belt. This view is supported by U-Pb and I-Xe chronologies, which show that water delivery peaked approximately 100 million years after the isolation of the Solar System. Introduction of water into the terrestrial mantle triggered plate tectonics, which may have been crucial for the emergence of life. This mechanism may also have worked for the young Venus, but seems to have failed for Mars.

Event Recognition Based on Deep Learning in Chinese Texts

PubMed Central

Zhang, Yajun; Liu, Zongtian; Zhou, Wen

2016-01-01

Event recognition is the most fundamental and critical task in event-based natural language processing systems. Existing event recognition methods based on rules and shallow neural networks have certain limitations. For example, extracting features using methods based on rules is difficult; methods based on shallow neural networks converge too quickly to a local minimum, resulting in low recognition precision. To address these problems, we propose the Chinese emergency event recognition model based on deep learning (CEERM). Firstly, we use a word segmentation system to segment sentences. According to event elements labeled in the CEC 2.0 corpus, we classify words into five categories: trigger words, participants, objects, time and location. Each word is vectorized according to the following six feature layers: part of speech, dependency grammar, length, location, distance between trigger word and core word and trigger word frequency. We obtain deep semantic features of words by training a feature vector set using a deep belief network (DBN), then analyze those features in order to identify trigger words by means of a back propagation neural network. Extensive testing shows that the CEERM achieves excellent recognition performance, with a maximum F-measure value of 85.17%. Moreover, we propose the dynamic-supervised DBN, which adds supervised fine-tuning to a restricted Boltzmann machine layer by monitoring its training performance. Test analysis reveals that the new DBN improves recognition performance and effectively controls the training time. Although the F-measure increases to 88.11%, the training time increases by only 25.35%. PMID:27501231

Event Recognition Based on Deep Learning in Chinese Texts.

PubMed

Zhang, Yajun; Liu, Zongtian; Zhou, Wen

2016-01-01

Event recognition is the most fundamental and critical task in event-based natural language processing systems. Existing event recognition methods based on rules and shallow neural networks have certain limitations. For example, extracting features using methods based on rules is difficult; methods based on shallow neural networks converge too quickly to a local minimum, resulting in low recognition precision. To address these problems, we propose the Chinese emergency event recognition model based on deep learning (CEERM). Firstly, we use a word segmentation system to segment sentences. According to event elements labeled in the CEC 2.0 corpus, we classify words into five categories: trigger words, participants, objects, time and location. Each word is vectorized according to the following six feature layers: part of speech, dependency grammar, length, location, distance between trigger word and core word and trigger word frequency. We obtain deep semantic features of words by training a feature vector set using a deep belief network (DBN), then analyze those features in order to identify trigger words by means of a back propagation neural network. Extensive testing shows that the CEERM achieves excellent recognition performance, with a maximum F-measure value of 85.17%. Moreover, we propose the dynamic-supervised DBN, which adds supervised fine-tuning to a restricted Boltzmann machine layer by monitoring its training performance. Test analysis reveals that the new DBN improves recognition performance and effectively controls the training time. Although the F-measure increases to 88.11%, the training time increases by only 25.35%.

Long-Duration Orbit Exposure Experiment with Sub-Surface Microorganism from a Mars Terrestrial Analog

NASA Astrophysics Data System (ADS)

Davila, A. F.; Lim, D.; Fairen, A. G.; Uceda, E. R.; Zavaleta, J.; McKay, C.

2007-07-01

Orbit Exposure Experiments (OEE) allow us to test the possibility of life transfer between planets and moons. Deep sub-surface microorganisms may be the best candidates to survive long-term exposure to space conditions. A long duration OEE is proposed to test our hypothesis.

Inferences About the Early Moon From Gravity and Topography

NASA Technical Reports Server (NTRS)

Smith, D. E.; Zuber, M. T.

1998-01-01

Recent spacecraft missions to the Moon have significantly improved our knowledge of the lunar gravity and topography fields, and have raised some new and old questions about the early lunar history. It has frequently been assumed that the shape of the Moon today reflects an earlier equilibrium state and that the Moon has retained some internal strength. Recent analysis indicating a superisostatic state of some lunar basins lends support to this hypothesis. On its simplest level, the present shape of the Moon is slightly flattened by 2.2 +/- 0.2 km while its gravity field, represented by an equipotential surface, is flattened only about 0.5 km. The hydrostatic component to the flattening arising from the Moon's present day rotation contributes only 7 m. This difference between the topographic shape of the MOon and the shape of its gravitational equipotential has frequently been explained as the "memory" of an earlier moon that was rotating faster and had a correspondingly larger hydrostatic flattening. To obtain this amount of hydrostatic flattening from rotation alone, and accounting for the contribution of the present-day gravity field, the Moon's rotation rate would need to be about 15x greater than at present, leading ot a period of < 2 days. Maintaining its synchronous rotation with Earth would require a radius for the Moon's orbit of approximately 9 Earth Radii. Unfortunately, our confidence in the observed lunar flattening is not as great as we would like. The uncertainty of .02 km may not properly reflect the limitations of the Clementine dataset, which did not sample poleward of latitudes 81 N and 79 S. Also, the large variation of topography +/- 8 km seen on the MOon dwarfs our estimate fo the flattening. Further the lunar south pole is on the edge of, or possibly inside the massive deep, South Pole-Aitken Basin. Thus, polar radii could be underestimated. This would yield a smaller flattening, which would imply a greater lunar rotation period and orbital radius. However, Basin compensation states and analyses of support and relaxation of topography at long wavelengths point to a lunar shape that has retained a flattening from an earlier faster rotation period.

CubeX: The CubeSAT X-ray Telescope for Elemental Abundance Mapping of Airless Bodies and X-ray Pulsar Navigation

NASA Astrophysics Data System (ADS)

Nittler, L. R.; Hong, J.; Kenter, A.; Romaine, S.; Allen, B.; Kraft, R.; Masterson, R.; Elvis, M.; Gendreau, K.; Crawford, I.; Binzel, R.; Boynton, W. V.; Grindlay, J.; Ramsey, B.

2017-12-01

The surface elemental composition of a planetary body provides crucial information about its origin, geological evolution, and surface processing, all of which can in turn provide information about solar system evolution as a whole. Remote sensing X-ray fluorescence (XRF) spectroscopy has been used successfully to probe the major-element compositions of airless bodies in the inner solar system, including the Moon, near-Earth asteroids, and Mercury. The CubeSAT X-ray Telescope (CubeX) is a concept for a 6U planetary X-ray telescope (36U with S/C), which utilizes Miniature Wolter-I X-ray optics (MiXO), monolithic CMOS and SDD X-ray sensors for the focal plane, and a Solar X-ray Monitor (heritage from the REXIS XRF instrument on NASA's OSIRIS-REx mission). CubeX will map the surface elemental composition of diverse airless bodies by spectral measurement of XRF excited by solar X-rays. The lightweight ( 1 kg) MiXO optics provide sub-arcminute resolution with low background, while the inherently rad-hard CMOS detectors provide improved spectral resolution ( 150 eV) at 0 °C. CubeX will also demonstrate X-ray pulsar timing based deep space navigation (XNAV). Successful XNAV will enable autonomous deep navigation with little to no support from the Deep Space Network, hence lowering the operation cost for many more planetary missions. Recently selected by NASA Planetary Science Deep Space SmallSat Studies, the first CubeX concept, designed to rideshare to the Moon as a secondary spacecraft on a primary mission, is under study in collaboration with the Mission Design Center at NASA Ames Research Center. From high altitude ( 6,000 km) frozen polar circular orbits, CubeX will study > 8 regions ( 110 km) of geological interest on the Moon over one year to produce a high resolution ( 2-3 km) elemental abundance map of each region. The novel focal plane design of CubeX also allows us to evaluate the performance of absolute navigation by sequential observations of several millisecond pulsars without moving parts.

Geophysical evidence for melt in the deep lunar interior and implications for lunar evolution (Invited)

NASA Astrophysics Data System (ADS)

Khan, A.; Connolly, J. A.; Pommier, A.

2013-12-01

Analysis of lunar seismic and lunar laser ranging data has yielded evidence that has been interpreted to indicate a molten zone in the lower-most mantle and/or the outer core of the Moon. Such a zone would provide strong constraints on models of the thermal evolution of the Moon. Here we invert lunar geophysical data in combination with phase-equilibrium modeling to derive information about the thermo-chemical and physical structure of the deep lunar interior. Specifically, we assess whether a molten layer is required by the geophysical data and, if so, its likely composition and physical properties (e.g., density and seismic wave speeds). The data considered are mean mass and moment of inertia, second-degree tidal Love number, and frequency-dependent electromagnetic sounding data. The main conclusion drawn from this study is that a region with high dissipation located deep within the Moon is indeed required to explain the geophysical data. If this dissipative region is located within the mantle, then the solidus is crossed at a depth of ~1200 km (>1600 deg C). The apparent absence of far-side deep moonquakes (DMQs) is supporting evidence for a highly dissipative layer. Inverted compositions for the partially molten layer (typically 100--200 km thick) are enriched in FeO and TiO2 relative to the surrounding mantle. While the melt phase in >95 % of inverted models is neutrally buoyant at pressures of ~4.5--4.6 GPa, the melt contains less TiO2 (>~4 wt %) than the Ti-rich (~16 wt % TiO2) melts that produced a set of high-density primitive lunar magmas (~3.4 g/ccm). Melt densities computed here range from 3.3 to 3.4 g/ccm bracketing the density of lunar magmas with moderate-to-high TiO2 contents. Our results are consistent with a model of lunar evolution in which the cumulate pile formed from crystallization of the magma ocean as it overturned, trapping heat-producing elements in the lower mantle.

Alternative method for VIIRS Moon in space view process

NASA Astrophysics Data System (ADS)

Anderson, Samuel; Chiang, Kwofu V.; Xiong, Xiaoxiong

2013-09-01

The Visible Infrared Imaging Radiometer Suite (VIIRS) is a radiometric sensing instrument currently operating onboard the Suomi National Polar-orbiting Partnership (S-NPP) spacecraft. It provides high spatial-resolution images of the emitted and reflected radiation from the Earth and its atmosphere in 22 spectral bands (16 moderate resolution bands M1-M16, 5 imaging bands I1-I5, and 1 day/night pan band DNB) spanning the visible and infrared wavelengths from 412 nm to 12 μm. Just prior to each scan it makes of the Earth, the VIIRS instrument makes a measurement of deep space to serve as a background reference. These space view (SV) measurements form a crucial input to the VIIRS calibration process and are a major determinant of its accuracy. On occasion, the orientation of the Suomi NPP spacecraft coincides with the position of the moon in such a fashion that the SV measurements include light from the moon, rendering the SV measurements unusable for calibration. This paper investigates improvements to the existing baseline SV data processing algorithm of the Sensor Data Record (SDR) processing software. The proposed method makes use of a Moon-in-SV detection algorithm that identifies moon-contaminated SV data on a scan-by-scan basis. Use of this algorithm minimizes the number of SV scans that are rejected initially, so that subsequent substitution processes are always able to find alternative substitute SV scans in the near vicinity of detected moon-contaminated scans.

Evaluation of Human and AutomationRobotics Integration Needs for Future Human Exploration Missions

NASA Technical Reports Server (NTRS)

Marquez, Jessica J.; Adelstein, Bernard D.; Ellis, Stephen; Chang, Mai Lee; Howard, Robert

2016-01-01

NASA employs Design Reference Missions (DRMs) to define potential architectures for future human exploration missions to deep space, the Moon, and Mars. While DRMs to these destinations share some components, each mission has different needs. This paper focuses on the human and automation/robotic integration needs for these future missions, evaluating them with respect to NASA research gaps in the area of space human factors engineering. The outcomes of our assessment is a human and automation/robotic (HAR) task list for each of the four DRMs that we reviewed (i.e., Deep Space Sortie, Lunar Visit/Habitation, Deep Space Habitation, and Planetary), a list of common critical HAR factors that drive HAR design.

Chemical stratigraphy of the Apollo 17 deep drill cores 70009-70007

NASA Technical Reports Server (NTRS)

Ehmann, W. D.; Ali, M. Z.

1977-01-01

A description is presented of an analysis of a total of 26 samples from three core segments (70009, 70008, 70007) of the Apollo 17 deep drill string. The deep drill string was taken about 700 m east of the Camelot Crater in the Taurus-Littrow region of the moon. Three core segments have been chemically characterized from the mainly coarse-grained upper portion of the deep drill string. The chemical data suggest that the entire 70007-70009 portion of the deep drill string examined was not deposited as a single unit, but was formed by several events sampling slightly different source materials which may have occurred over a relatively short period of time. According to the data from drill stem 70007, there were at least two phases of deposition. Core segment 70009 is probably derived from somewhat different source material than 70008. It seems to be a very well mixed material.

The U.S. Rosetta Project : eighteen months in flight

NASA Technical Reports Server (NTRS)

Alexander, Claudia J.; Gulkis, Samuel; Frerking, Margaret A.; Holmes, Dwight P.; Weissman, Paul A.; Burch, J.; Stern, A.; Goldstein, R.; Parker, J.; Cravens, T.;

Simulation of Earth-Moon-Mars Environments for the Assessment of Organ Doses

NASA Astrophysics Data System (ADS)

Kim, M. Y.; Schwadron, N. A.; Townsend, L.; Cucinotta, F. A.

2010-12-01

Space radiation environments for historically large solar particle events (SPE) and galactic cosmic rays (GCR) at solar minimum and solar maximum are simulated in order to characterize exposures to radio-sensitive organs for missions to low-Earth orbit (LEO), moon, and Mars. Primary and secondary particles for SPE and GCR are transported through the respective atmosphere of Earth or Mars, space vehicle, and astronaut’s body tissues using the HZETRN/QMSFRG computer code. In LEO, exposures are reduced compared to deep space because particles are deflected by the Earth’s magnetic field and absorbed by the solid body of the Earth. Geomagnetic transmission function as a function of altitude was applied for the particle flux of charged particles, and the shift of the organ exposures to higher velocity or lower stopping powers compared to those in deep space was analyzed. In the transport through Mars atmosphere, a vertical distribution of atmospheric thickness was calculated from the temperature and pressure data of Mars Global Surveyor, and the directional cosine distribution was implemented to describe the spherically distributed atmospheric distance along the slant path at each altitude. The resultant directional shielding by Mars atmosphere at solar minimum and solar maximum was used for the particle flux simulation at various altitudes on the Martian surface. Finally, atmospheric shielding was coupled with vehicle and body shielding for organ dose estimates. We made predictions of radiation dose equivalents and evaluated acute symptoms at LEO, moon, and Mars at solar minimum and solar maximum.

Power Processing for a Conceptual Project Prometheus Electric Propulsion System

NASA Technical Reports Server (NTRS)

Scina, Joseph E., Jr.; Aulisio, Michael; Gerber, Scott S.; Hewitt, Frank; Miller, Leonard; Elbuluk, Malik; Pinero, Luis R. (Technical Monitor)

2005-01-01

NASA has proposed a bold mission to orbit and explore the moons of Jupiter. This mission, known as the Jupiter Icy Moons Orbiter (JIMO), would significantly increase NASA s capability to explore deep space by making use of high power electric propulsion. One electric propulsion option under study for JIMO is an ion propulsion system. An early version of an ion propulsion system was successfully used on NASA's Deep Space 1 mission. One concept for an ion thruster system capable of meeting the current JIMO mission requirement would have individual thrusters that are 16 to 25 kW each and require voltages as high as 8.0 kV. The purpose of this work is to develop power processing schemes for delivering the high voltage power to the spacecraft ion thrusters based upon a three-phase AC distribution system. In addition, a proposed DC-DC converter topology is presented for an ion thruster ancillary supply based upon a DC distribution system. All specifications discussed in this paper are for design convenience and are speculative in nature.

Enzyme-triggered size shrink and laser-enhanced NO release nanoparticles for deep tumor penetration and combination therapy.

PubMed

Hu, Chuan; Cun, Xingli; Ruan, Shaobo; Liu, Rui; Xiao, Wei; Yang, Xiaotong; Yang, Yuanyuan; Yang, Chuanyao; Gao, Huile

2018-06-01

Chemotherapy remains restricted by poor drug delivery efficacy due to the heterogenous nature of tumor. Herein, we presented a novel nanoparticle that could not only response to the tumor microenvironment but also modulate it for deep tumor penetration and combination therapy. The intelligent nanoparticle (IDDHN) was engineered by hyaluronidase (HAase)-triggered size shrinkable hyaluronic acid shells, which were modified with NIR laser sensitive nitric oxide donor (HN), small-sized dendrimeric prodrug (IDD) of doxorubicin (DOX) as chemotherapy agent and indocyanine green (ICG) as photothermal agent into a single nanoparticle. IDDHN displayed synergistic deep penetration both in vitro and in vivo, owing to the enzymatically degradable HN shell mediated by HAase and laser-enhanced NO release triggered deep penetration upon strong hyperthermia effect of ICG under the NIR laser irradiation. The therapeutic effect of IDDHN was verified in 4T1 xenograft tumor model, and IDDHN showed a much better antitumor efficiency with few side effects upon NIR laser irradiation. Therefore, the valid of this study might provide a novel tactic for engineering nanoparticles both response to and modulate the tumor microenvironment for improving penetration and heterogeneity distribution of therapeutic agents in tumor. Copyright © 2018 Elsevier Ltd. All rights reserved.

Meteorological variables associated with deep slab avalanches on persistent weak layers

USGS Publications Warehouse

Marienthal, Alex; Hendrikx, Jordy; Birkeland, Karl; Irvine, Kathryn M.

2014-01-01

Deep slab avalanches are a particularly challenging avalanche forecasting problem. These avalanches are typically difficult to trigger, yet when they are triggered they tend to propagate far and result in large and destructive avalanches. For this work we define deep slab avalanches as those that fail on persistent weak layers deeper than 0.9m (3 feet), and that occur after February 1st. We utilized a 44-year record of avalanche control and meteorological data from Bridger Bowl Ski Area to test the usefulness of meteorological variables for predicting deep slab avalanches. As in previous studies, we used data from the days preceding deep slab cycles, but we also considered meteorological metrics over the early months of the season. We utilized classification trees for our analyses. Our results showed warmer temperatures in the prior twenty-four hours and more loading over the seven days before days with deep slab avalanches on persistent weak layers. In line with previous research, extended periods of above freezing temperatures led to days with deep wet slab avalanches on persistent weak layers. Seasons with either dry or wet avalanches on deep persistent weak layers typically had drier early months, and often had some significant snow depth prior to those dry months. This paper provides insights for ski patrollers, guides, and avalanche forecasters who struggle to forecast deep slab avalanches on persistent weak layers late in the season.

Rationale and Roadmap for Moon Exploration

NASA Astrophysics Data System (ADS)

Foing, B. H.; ILEWG Team

We discuss the different rationale for Moon exploration. This starts with areas of scientific investigations: clues on the formation and evolution of rocky planets, accretion and bombardment in the inner solar system, comparative planetology processes (tectonic, volcanic, impact cratering, volatile delivery), records astrobiology, survival of organics; past, present and future life. The rationale includes also the advancement of instrumentation: Remote sensing miniaturised instruments; Surface geophysical and geochemistry package; Instrument deployment and robotic arm, nano-rover, sampling, drilling; Sample finder and collector. There are technologies in robotic and human exploration that are a drive for the creativity and economical competitivity of our industries: Mecha-electronics-sensors; Tele control, telepresence, virtual reality; Regional mobility rover; Autonomy and Navigation; Artificially intelligent robots, Complex systems, Man-Machine interface and performances. Moon-Mars Exploration can inspire solutions to global Earth sustained development: In-Situ Utilisation of resources; Establishment of permanent robotic infrastructures, Environmental protection aspects; Life sciences laboratories; Support to human exploration. We also report on the IAA Cosmic Study on Next Steps In Exploring Deep Space, and ongoing IAA Cosmic Studies, ILEWG/IMEWG ongoing activities, and we finally discuss possible roadmaps for robotic and human exploration, starting with the Moon-Mars missions for the coming decade, and building effectively on joint technology developments.

KSC-2014-3218

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Rick Armstrong addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Rick is Neil Armstrong's son. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3200

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, visiting Apollo astronauts have a group portrait taken in front of the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are Mike Collins, Buzz Aldrin and Jim Lovell. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3213

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3205

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo 11 astronaut Michael Collins participates in a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3252

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo 11 command module pilot Michael Collins signs a banner displaying the new name of the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. The banner signing followed a ceremony renaming the refurbished building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3208

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana, left, and NASA Administrator Charles Bolden participate a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3212

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo 11 astronaut Michael Collins addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3231

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo astronauts tour the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Viewing the Orion crew module stacked on top of the service module from left, are Apollo 11 astronaut Michael Collins, Apollo astronaut Jim Lovell, and Apollo 11 astronaut Buzz Aldrin. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System. Orion is designed to take humans farther than they've ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3206

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3204

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo 11 astronaut Buzz Aldrin participates in a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3219

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, media representatives turn out for a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay, in which the ceremony was held, is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3209

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo astronauts participate in a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are Jim Lovell, Buzz Aldrin and Michael Collins. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3223

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo 11 astronaut Michael Collins gets a close look at an Apollo-era spacesuit following its unveiling in the lobby of the newly named Neil Armstrong Operations and Checkout Building. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

KSC-2014-3199

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts have a group portrait taken in front of the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are NASA Administrator Charles Bolden, Apollo astronauts Mike Collins, Buzz Aldrin and Jim Lovell, and Center Director Robert Cabana. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3211

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo 11 astronaut Buzz Aldrin addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3221

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana, left, and NASA Administrator Charles Bolden unveil a plaque on display in the lobby of the newly named Neil Armstrong Operations and Checkout Building. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

KSC-2014-3210

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Apollo astronaut Jim Lovell addresses the audience at a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Lovell served on the crews of Apollo 8 and Apollo 13. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3220

NASA Image and Video Library

2014-07-21

KSC-2014-3220 – CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana unveils an Apollo-era spacesuit on display in the lobby of the newly named Neil Armstrong Operations and Checkout Building. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

Aerial Vehicles to Detect Maximum Volume of Plume Material Associated with Habitable Areas in Extreme Environments

NASA Technical Reports Server (NTRS)

Gunasekara, Onalli; Wong, Uland Y.; Furlong, Michael P.; Dille, Michael

2017-01-01

Current technologies of exploring habitable areas of icy moons are limited to flybys of space probes. This research project addresses long-term navigation of icy moons by developing a MATLAB adjustable trajectory based on the volume of plume material observed. Plumes expose materials from the sub-surface without accessing the subsurface. Aerial vehicles capable of scouting vapor plumes and detecting maximum plume material volumes, which are considered potentially habitable in inhospitable environments, would enable future deep-space missions to search for extraterrestrial organisms on the surface of icy moons. Although this platform is still a prototype, it demonstrates the potential aerial vehicles can have in improving the capabilities of long-term space navigation and enabling technology for detecting life in extreme environments. Additionally, this work is developing the capabilities that could be utilized as a platform for space biology research. For example, aerial vehicles that are sent to map extreme environments of icy moons or the planet Mars, could also carry small payloads with automated cell-biology experiments, designed to probe the biological response of low-gravity and high-radiation planetary environments, serving as a pathfinder for future human missions.

A Flexible Path for Human and Robotic Space Exploration

NASA Technical Reports Server (NTRS)

Korsmeyer, David J.; Landis, Robert; Merrill, Raymond Gabriel; Mazanek, Daniel D.; Falck, Robert D.; Adams, Robert B.

2010-01-01

During the summer of 2009, a flexible path scenario for human and robotic space exploration was developed that enables frequent, measured, and publicly notable human exploration of space beyond low-Earth orbit (LEO). The formulation of this scenario was in support of the Exploration Beyond LEO subcommittee of the Review of U.S. Human Space Flight Plans Committee that was commissioned by President Obama. Exploration mission sequences that allow humans to visit a wide number of inner solar system destinations were investigated. The scope of destinations included the Earth-Moon and Earth-Sun Lagrange points, near-Earth objects (NEOs), the Moon, and Mars and its moons. The missions examined assumed the use of Constellation Program elements along with existing launch vehicles and proposed augmentations. Additionally, robotic missions were envisioned as complements to human exploration through precursor missions, as crew emplaced scientific investigations, and as sample gathering assistants to the human crews. The focus of the flexible path approach was to gain ever-increasing operational experience through human exploration missions ranging from a few weeks to several years in duration, beginning in deep space beyond LEO and evolving to landings on the Moon and eventually Mars.

Spaceport operations for deep space missions

NASA Technical Reports Server (NTRS)

Holt, Alan C.

1990-01-01

Space Station Freedom is designed with the capability to cost-effectively evolve into a transportation node which can support manned lunar and Mars missions. To extend a permanent human presence to the outer planets (moon outposts) and to nearby star systems, additional orbiting space infrastructure and great advances in propulsion system and other technologies will be required. To identify primary operations and management requirements for these deep space missions, an interstellar design concept was developed and analyzed. The assembly, test, servicing, logistics resupply, and increment management techniques anticipated for lunar and Mars missions appear to provide a pattern which can be extended in an analogous manner to deep space missions. A long range, space infrastructure development plan (encompassing deep space missions) coupled with energetic, breakthrough level propulsion research should be initiated now to assist in making the best budget and schedule decisions.

Built to Explore MSFC-SLS-077

NASA Image and Video Library

2018-04-20

NASA's Space Launch System, the world's most powerful rocket, will enable a new era of exploration. With NASA's Orion spacecraft, SLS will launch astronauts on missions to the Moon, Mars and beyond. Exploration Mission-1, the first integrated flight of SLS and an uncrewed Orion, will be the first in a series of increasingly complex missions that will provide the foundation for human deep-space exploration and demonstrate NASA's commitment and capability to extend human existence beyond low-Earth orbit. Launching from NASA's Kennedy Space Center in Florida, the nation's premier multi-user spaceport, SLS will be the only rocket capable of sending crew and large cargo to the Moon in a single launch. (NASA/MSFC)

Realtime processing of LOFAR data for the detection of nano-second pulses from the Moon

NASA Astrophysics Data System (ADS)

Winchen, T.; Bonardi, A.; Buitink, S.; Corstanje, A.; Enriquez, J. E.; Falcke, H.; Hörandel, J. R.; Mitra, P.; Mulrey, K.; Nelles, A.; Rachen, J. P.; Rossetto, L.; Schellart, P.; Scholten, O.; Thoudam, S.; Trinh, T. N. G.; ter Veen, S.; KSP, The LOFAR Cosmic Ray

2017-10-01

The low flux of the ultra-high energy cosmic rays (UHECR) at the highest energies provides a challenge to answer the long standing question about their origin and nature. Even lower fluxes of neutrinos with energies above 1022 eV are predicted in certain Grand-Unifying-Theories (GUTs) and e.g. models for super-heavy dark matter (SHDM). The significant increase in detector volume required to detect these particles can be achieved by searching for the nanosecond radio pulses that are emitted when a particle interacts in Earth’s moon with current and future radio telescopes. In this contribution we present the design of an online analysis and trigger pipeline for the detection of nano-second pulses with the LOFAR radio telescope. The most important steps of the processing pipeline are digital focusing of the antennas towards the Moon, correction of the signal for ionospheric dispersion, and synthesis of the time-domain signal from the polyphased-filtered signal in frequency domain. The implementation of the pipeline on a GPU/CPU cluster will be discussed together with the computing performance of the prototype.

Mars Radiation Risk Assessment and Shielding Design for Long-term Exposure to Ionizing Space Radiation

NASA Technical Reports Server (NTRS)

Tripathi, Ram K.; Nealy, John E.

2007-01-01

NASA is now focused on the agency's vision for space exploration encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. As a result, there is a focus on long duration space missions. NASA is committed to the safety of the missions and the crew, and there is an overwhelming emphasis on the reliability issues for space missions and the habitat. The cost-effective design of the spacecraft demands a very stringent requirement on the optimization process. Exposure from the hazards of severe space radiation in deep space and/or long duration missions is a critical design constraint and a potential 'show stopper'. Thus, protection from the hazards of severe space radiation is of paramount importance to the agency's vision. It is envisioned to have long duration human presence on the Moon for deep space exploration. The exposures from ionizing radiation - galactic cosmic radiation and solar particle events - and optimized shield design for a swing-by and a long duration Mars mission have been investigated. It is found that the technology of today is inadequate for safe human missions to Mars, and revolutionary technologies need to be developed for long duration and/or deep space missions. The study will provide a guideline for radiation exposure and protection for long duration missions and career astronauts and their safety.

The tungsten isotopic composition of the Earth's mantle before the terminal bombardment.

PubMed

Willbold, Matthias; Elliott, Tim; Moorbath, Stephen

2011-09-07

Many precious, 'iron-loving' metals, such as gold, are surprisingly abundant in the accessible parts of the Earth, given the efficiency with which core formation should have removed them to the planet's deep interior. One explanation of their over-abundance is a 'late veneer'--a flux of meteorites added to the Earth after core formation as a 'terminal' bombardment that culminated in the cratering of the Moon. Some 3.8 billion-year-old rocks from Isua, Greenland, are derived from sources that retain an isotopic memory of events pre-dating this cataclysmic meteorite shower. These Isua samples thus provide a window on the composition of the Earth before such a late veneer and allow a direct test of its importance in modifying the composition of the planet. Using high-precision (less than 6 parts per million, 2 standard deviations) tungsten isotope analyses of these rocks, here we show that they have a isotopic tungsten ratio (182)W/(184)W that is significantly higher (about 13 parts per million) than modern terrestrial samples. This finding is in good agreement with the expected influence of a late veneer. We also show that alternative interpretations, such as partial remixing of a deep-mantle reservoir formed in the Hadean eon (more than four billion years ago) or core-mantle interaction, do not explain the W isotope data well. The decrease in mantle (182)W/(184)W occurs during the Archean eon (about four to three billion years ago), potentially on the same timescale as a notable decrease in (142)Nd/(144)Nd (refs 3 and 6). We speculate that both observations can be explained if late meteorite bombardment triggered the onset of the current style of mantle convection.

Deep Space Test Bed for Radiation Studies

NASA Technical Reports Server (NTRS)

Adams, James H.; Adcock, Leonard; Apple, Jeffery; Christl, Mark; Cleveand, William; Cox, Mark; Dietz, Kurt; Ferguson, Cynthia; Fountain, Walt; Ghita, Bogdan

2006-01-01

The Deep Space Test-Bed (DSTB) Facility is designed to investigate the effects of galactic cosmic rays on crews and systems during missions to the Moon or Mars. To gain access to the interplanetary ionizing radiation environment the DSTB uses high-altitude polar balloon flights. The DSTB provides a platform for measurements to validate the radiation transport codes that are used by NASA to calculate the radiation environment within crewed space systems. It is also designed to support other Exploration related investigations such as measuring the shielding effectiveness of candidate spacecraft and habitat materials, testing new radiation monitoring instrumentation and flight avionics and investigating the biological effects of deep space radiation. We describe the work completed thus far in the development of the DSTB and its current status.

With Eyes on the Future, Marshall Leads the Way to Deep Space in 2017

NASA Image and Video Library

2017-12-27

NASA's Marshall Space Flight Center in Huntsville, Alabama, led the way in space exploration in 2017. Marshall's work is advancing how we explore space and preparing for deep-space missions to the Moon, Mars and beyond. Progress continued on NASA's Space Launch System that will enable missions beyond Earth's orbit, while flight controllers at "Science Central" for the International Space Station coordinated research and experiments with astronauts in orbit, learning how to live in space. At Marshall, 2017 was also marked with ground-breaking discoveries, innovations that will send us into deep space, and events that will inspire future generations of explorers. Follow along in 2018 as Marshall continues to advance space exploration: www.nasa.gov/marshall

The formation of ore mineral deposits on the Moon: A feasibility study

NASA Technical Reports Server (NTRS)

Taylor, Lawrence A.; Lu, Fengxiang

1992-01-01

Most of the ore deposits on Earth are the direct result of formation by hydrothermal solutions. Analogous mineral concentrations do not occur on the Moon, however, because of the absence of water. Stratified ore deposits form in layered instrusives on Earth due to fractional crystallization of magma and crystal settling of high-density minerals, particularly chromium in the mineral chromite. We have evaluated the possibility of such mineral deposition on the Moon, based upon considerations of 'particle settling velocities' in lunar vs. terrestrial magmas. A first approximation of Stoke's Law would seem to indicate that the lower lunar gravity (1/6 terrestrial) would result in slower crystal settling on the Moon. However, the viscosity of the silicate melt is the most important factor affecting the settling velocity. The viscosities of typical lunar basaltic melts are 10-100 times less than their terrestrial analogs. These lower viscosities result from two factors: (1) lunar basaltic melts are typically higher in FeO and lower in Al2O3, Na2O, and K2O than terrestrial melts; and (2) lunar igneous melts and phase equilibria tend to be 100-150 C higher than terrestrial, largely because of the general paucity of water and other volatile phases on the Moon. Therefore, particle settling velocities on the Moon are 5-10 times greater than those on Earth. It is highly probable that stratiform ore deposits similar to those on Earth exist on the Moon. The most likely ore minerals involved are chromite, ilmenite, and native FeNi metal. In addition, the greater settling velocities of periodotite in lunar magmas indicate that the buoyancy effects of the melt are less than on Earth. Consequently, the possibility is considerably less than on Earth of deep-seated volcanism transporting upper mantle/lower crustal xenoliths to the surface of the Moon, such as occurs in kimberlites on Earth.

Lunar Polar Coring Lander

NASA Technical Reports Server (NTRS)

Angell, David; Bealmear, David; Benarroche, Patrice; Henry, Alan; Hudson, Raymond; Rivellini, Tommaso; Tolmachoff, Alex

1990-01-01

Plans to build a lunar base are presently being studied with a number of considerations. One of the most important considerations is qualifying the presence of water on the Moon. The existence of water on the Moon implies that future lunar settlements may be able to use this resource to produce things such as drinking water and rocket fuel. Due to the very high cost of transporting these materials to the Moon, in situ production could save billions of dollars in operating costs of the lunar base. Scientists have suggested that the polar regions of the Moon may contain some amounts of water ice in the regolith. Six possible mission scenarios are suggested which would allow lunar polar soil samples to be collected for analysis. The options presented are: remote sensing satellite, two unmanned robotic lunar coring missions (one is a sample return and one is a data return only), two combined manned and robotic polar coring missions, and one fully manned core retrieval mission. One of the combined manned and robotic missions has been singled out for detailed analysis. This mission proposes sending at least three unmanned robotic landers to the lunar pole to take core samples as deep as 15 meters. Upon successful completion of the coring operations, a manned mission would be sent to retrieve the samples and perform extensive experiments of the polar region. Man's first step in returning to the Moon is recommended to investigate the issue of lunar polar water. The potential benefits of lunar water more than warrant sending either astronauts, robots or both to the Moon before any permanent facility is constructed.

Review of exchange processes on Ganymede in view of its planetary protection categorization.

PubMed

Grasset, O; Bunce, E J; Coustenis, A; Dougherty, M K; Erd, C; Hussmann, H; Jaumann, R; Prieto-Ballesteros, O

2013-10-01

In this paper, we provide a detailed review of Ganymede's characteristics that are germane to any consideration of its planetary protection requirements. Ganymede is the largest moon in our solar system and is the subject of one of the main science objectives of the JUICE mission to the jovian system. We explore the probability of the occurrence of potentially habitable zones within Ganymede at present, including those both within the deep liquid ocean and those in shallow liquid reservoirs. We consider the possible exchange processes between the surface and any putative habitats to set some constraints on the planetary protection approach for this moon. As a conclusion, the "remote" versus "significant" chance of contamination will be discussed, according to our current understanding of this giant icy moon. Based on the different estimates we investigate here, it appears extremely unlikely that material would be exchanged downward through the upper icy layer of Ganymede and, thus, bring material into the ocean over timescales consistent with the survival of microorganisms.

ESA SMART-1 mission: review of results and legacy 10 years after launch

NASA Astrophysics Data System (ADS)

Foing, Bernard

2014-05-01

We review ESA's SMART-1 highlights and legacy 10 years after launch. The SMART-1 mission to the Moon achieved record firsts such as: 1) first Small Mission for Advanced Research and Technology; with spacecraft built and integrated in 2.5 years and launched 3.5 years after mission approval; 2) first mission leaving the Earth orbit using solar power alone with demonstration for future deep space missions such as BepiColombo; 3) most fuel effective mission (60 litres of Xenon) and longest travel (13 month) to the Moon!; 4) first ESA mission reaching the Moon and first European views of lunar poles; 5) first European demonstration of a wide range of new technologies: Li-Ion modular battery, deep-space communications in X- and Ka-bands, and autonomous positioning for navigation; 6) first lunar demonstration of an infrared spectrometer and of a Swept Charge Detector Lunar X-ray fluorescence spectrometer ; 7) first ESA mission with opportunity for lunar science, elemental geochemistry, surface mineralogy mapping, surface geology and precursor studies for exploration; 8) first controlled impact landing on the Moon with real time observations campaign; 9) first mission supporting goals of the ILEWG/COSPAR International Lunar Exploration Working Group in technical and scientific exchange, international collaboration, public and youth engagement; 10) first mission preparing the ground for ESA collaboration in Chandrayaan-1, Chang'E1-2-3 and near-future landers, sample return and human lunar missions. The SMART-1 technology legacy is applicable to geostationary satellites and deep space missions using solar electric propulsion. The SMART-1 archive observations have been used to support scientific research and prepare subsequent lunar missions and exploration. Most recent SMART-1 results are relevant to topics on: 1) the study of properties of the lunar dust, 2) impact craters and ejecta, 3) the study of illumination, 4) observations and science from the Moon, 5) support to future missions, 6) identifying and characterising sites for exploration and exploitation. This legacy is relevant to the preparation for future orbiters, landers, sample return, a global robotic village, human missions and international lunar bases (consistent with ILEWG, COSPAR and Global Space Exploration roadmaps). Link: http://sci.esa.int/smart-1/ References and citations: http://scholar.google.nl/scholar?&q=smart-1+moon **We acknowledge ESA, member states, industry and institutes for their contribution, and the members of SMART-1 Teams: G.Racca and SMART-1 Project Team, O. Camino and SMART-1 Operations Team, D. Frew and SMART-1 STOC, B.H. Foing and STWT, B. Grieger, D. Koschny, J.-L. Josset, S. Beauvivre, M. Ellouzi, S. Peters, A. Borst, E. Martellato, M. Almeida, J.Volp, D. Heather, M. Grande, J. Huovelin, H.U. Keller, U. Mall, A. Nathues, A. Malkki, W. Schmidt, G. Noci, Z. Sodnik, B. Kellett, P. Pinet, S. Chevrel, P. Cerroni, M.C. de Sanctis, M.A. Barucci, S. Erard, D. Despan, K. Muinonen, V. Shevchenko, Y. Shkuratov, P. McMannamon, P. Ehrenfreund, C. Veillet, M. Burchell, other Co-Investigators, associated scientists, collaborators, students and colleagues.

Treatment of temporomandibular myofascial pain with deep dry needling

PubMed Central

Gonzalez-Perez, Luis M.; Granados-Nuñez, Mercedes; Urresti-Lopez, Francisco J.

2012-01-01

Objectives: The present study was designed to evaluate the usefulness of deep dry needling in the treatment of temporomandibular myofascial pain. Study Design: We selected 36 patients with myofascial pain located in the external pterygoid muscle (30 women/6 men, mean age=27 years with SD±6,5). We studied differences in pain with a visual analog scale and range of mandibular movements before and after intervention. Results: We found a statistically significant relationship (p<0,01) between therapeutic intervention and the improvement of pain and jaw movements, which continued up to 6 months after treatment. Pain reduction was greater the higher was the intensity of pain at baseline. Conclusions: Although further studies are needed, our findings suggest that deep dry needling in the trigger point in the external pterygoid muscle can be effective in the management of patients with myofascial pain located in that muscle. Key words:Temporomandibular joint, myofascial pain, external pterygoid muscle, trigger point, deep dry needling. PMID:22549679

A Novel Benzoquinone Compound Isolated from Deep-Sea Hydrothermal Vent Triggers Apoptosis of Tumor Cells.

PubMed

Xu, Chenxi; Sun, Xumei; Jin, Min; Zhang, Xiaobo

2017-06-26

Microorganisms are important sources for screening bioactive natural products. However, natural products from deep-sea microbes have not been extensively explored. In this study, the metabolites of bacteriophage GVE2 -infected ( Geobacillus sp. E263 virus) thermophilic bacterium Geobacillus sp. E263, which was isolated from a deep-sea hydrothermal vent, were characterized. A novel quinoid compound, which had anti-tumor activity, was isolated from the phage-challenged thermophile. The chemical structure analysis showed that this novel quinoid compound was 2-amino-6-hydroxy-[1,4]-benzoquinone. The results indicated that 2-amino-6-hydroxy-[1,4]-benzoquinone and its two derivatives could trigger apoptosis of gastric cancer cells and breast cancer cells by inducing the accumulation of intracellular reactive oxygen species. Therefore, our study highlighted that the metabolites from the phage-challenged deep-sea microbes might be a kind of promising sources for anti-tumor drug discovery, because of the similarity of metabolic disorder between bacteriophage-infected microbes and tumor cells.

Simulations of tremor-related creep reveal a weak crustal root of the San Andreas Fault

USGS Publications Warehouse

Shelly, David R.; Bradley, Andrew M.; Johnson, Kaj M.

2013-01-01

Deep aseismic roots of faults play a critical role in transferring tectonic loads to shallower, brittle crustal faults that rupture in large earthquakes. Yet, until the recent discovery of deep tremor and creep, direct inference of the physical properties of lower-crustal fault roots has remained elusive. Observations of tremor near Parkfield, CA provide the first evidence for present-day localized slip on the deep extension of the San Andreas Fault and triggered transient creep events. We develop numerical simulations of fault slip to show that the spatiotemporal evolution of triggered tremor near Parkfield is consistent with triggered fault creep governed by laboratory-derived friction laws between depths of 20–35 km on the fault. Simulated creep and observed tremor northwest of Parkfield nearly ceased for 20–30 days in response to small coseismic stress changes of order 104 Pa from the 2003 M6.5 San Simeon Earthquake. Simulated afterslip and observed tremor following the 2004 M6.0 Parkfield earthquake show a coseismically induced pulse of rapid creep and tremor lasting for 1 day followed by a longer 30 day period of sustained accelerated rates due to propagation of shallow afterslip into the lower crust. These creep responses require very low effective normal stress of ~1 MPa on the deep San Andreas Fault and near-neutral-stability frictional properties expected for gabbroic lower-crustal rock.

Probing reservoir-triggered earthquakes in Koyna, India, through scientific deep drilling

USGS Publications Warehouse

Gupta, H.; Nayak, Shailesh; Ellsworth, William L.; Rao, Y. J. B.; Rajan, S.; Bansal, B.K.; Purnachandra Rao, N.; Roy, S.; Arora, K.; Mohan, R.; Tiwari, V. M.; Satyanarayana, H. V. S.; Patro, P. K.; Shashidhar, D.; Mallika, K.

2014-01-01

We report here the salient features of the recently concluded International Continental Scientific Drilling Program (ICDP) workshop in Koyna, India. This workshop was a sequel to the earlier held ICDP workshop in Hyderabad and Koyna in 2011. A total of 49 experts (37 from India and 12 from 8 other countries) spent 3 days reviewing the work carried out during the last 3 years based on the recommendations of the 2011 workshop and suggesting the future course of action, including detailed planning for a full deep drilling proposal in Koyna, India. It was unanimously concluded that Koyna is one of the best sites anywhere in the world to investigate genesis of triggered earthquakes from near-field observations. A broad framework of the activities for the next phase leading to deep drilling has been worked out.

Impacts and tectonism in Earth and moon history of the past 3800 million years

NASA Technical Reports Server (NTRS)

Stothers, Richard B.

1992-01-01

The moon's surface, unlike the Earth's, displays a comparatively clear record of its past bombardment history for the last 3800 Myr, the time since active lunar tectonism under the massive premare bombardment ended. From Baldwin's (1987) tabulation of estimated ages for a representative sample of large lunar craters younger than 3800 Ma, six major cratering episodes can be discerned. These six bombardment episodes, which must have affected the Earth too, appear to match in time the six major episodes of orogenic tectonism on Earth, despite typical resolution errors of +/- 100 Myr and the great uncertainties of the two chronologies. Since more highly resolved events during the Cenozoic and Mesozoic Eras suggest the same correlation, it is possible that large impacts have influenced plate tectonics and other aspects of geologic history, perhaps by triggering flood basalt eruptions.

Assessment of pelvic floor muscles in women with deep endometriosis.

PubMed

Dos Bispo, Ana Paula Santos; Ploger, Christine; Loureiro, Alessandra Fernandes; Sato, Hélio; Kolpeman, Alexander; Girão, Manoel João Batista Castello; Schor, Eduardo

2016-09-01

To assess function and prevalence of spasms and trigger points of the pelvic floor muscles in women with deep endometriosis. One hundred and four (104) patients were assessed. Group 1 (G1) was composed of 52 subjects diagnosed with deep endometriosis proven by magnetic resonance imaging (MRI); Group 2 (G2) was composed of 52 women with no signs of endometriosis. Subjects from both G1 and G2 were seen at the Division of Pelvic Pain and Endometriosis and at Center for Prevention of Sexually Transmitted Diseases, both at Federal University of São Paulo (UNIFESP), respectively. A full physical therapy evaluation was carried out, including medical history, presence of dyspareunia and physical examination, which included detailed evaluation of pelvic floor muscles and occurrence of muscle spasm, trigger point and muscle function. The average age of the subjects in the study group was 36.4 and 30.9 years in the control group (p = 0.002). A greater prevalence of deep dyspareunia was found in the subjects in the endometriosis group when compared to the control group (p = 0.010). Women in G1 had higher prevalence of muscle spasms. In this group, 53.9 % had spasms-compared to only 17.3 % of women in G2 (p < 0.001). On the other hand, no significant difference between the groups (p = 0.153) was found while searching for the presence of trigger points. Women with deep endometriosis have increased prevalence of pelvic floor muscle spasms when compared to the control group.

Optimal Cooling of High Purity Germanium Spectrometers for Missions to Planets and Moons

NASA Astrophysics Data System (ADS)

Chernenko, A.; Kostenko, V.; Konev, S.; Rybkin, B.; Paschin, A.; Prokopenko, I.

2004-04-01

Gamma-ray spectrometers based on high purity germanium (HPGe) detectors are ultimately sensitive instruments for composition studies of surfaces of planets and moons. However, they require deep cooling well below 120K for the entire duration of space mission, and this challenges the feasibility of such instruments in the era of small and cost-efficient missions. In this paper we summarise our experience in the field of the theoretical and experimental studies of optimal cryogenic cooling of gamma-ray spectrometers based on HPGe detectors in order to find out how efficient, light and compact these instruments could be, provided such technologies like cryogenic heat pipe diodes (HPDs), efficient thermal insulation and efficient miniature cryocoolers are used.

KSC-2014-3215

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA Administrator Charles Bolden, left, presents Center Director Robert Cabana with an Apollo 11 patch that flew to the moon on the Apollo 11 mission and is signed by all three Apollo 11 astronauts. The patch will remain at Kennedy until the first human spaceflight to Mars, when it will fly once again. The presentation was made during a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay, in which the ceremony was held, is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

Achievements and Future Plan of Interplanetary CubeSats and Micro-Sats in Japan

NASA Astrophysics Data System (ADS)

Funase, Ryu

2016-07-01

This paper introduces Japanese achievements and future plans of CubeSats and Micro-Sats for deep space exploration. As the first step toward deep space mission by such tiny spacecraft, University of Tokyo and Japan Aerospace Exploration Agency (JAXA) developed the world's first deep space micro-spacecraft PROCYON (Proximate Object Close flYby with Optical Navigation). Its mission objective is to demonstrate a micro-spacecraft bus technology for deep space exploration and proximity flyby to asteroids performing optical measurements. PROCYON was launched into the Earth departure trajectory on December 3, 2014 together with Japanese asteroid sample return mission Hayabusa-2. PROCYON successfully completed the bus system demonstration mission in its interplanetary flight. Currently, Japan is not only pursuing the improvement and utilization of the demonstrated micro-sat deep space bus system with a weight of tens of kg or more for more practical scientific deep space missions, but also trying to develop smaller spacecraft with a weight of less than tens of kg, namely CubeSats, for deep space exploration. We are proposing a self-contained 6U CubeSat mission for the rideshare opportunity on the USA's SLS EM-1 mission, which will fly to a libration orbit around Earth-Moon L2 point and perform scientific observations of the Earth and the Moon. We are also seeking the possibility of CubeSats which is carried by a larger spacecraft to the destination and supports the mission by taking advantage of its low-cost and risk-tolerable feature. As an example of such style of CubeSat missions, we are studying a CubeSat for close observations of an asteroid, which will be carried to the target asteroid by a larger mother spacecraft. This CubeSat is released from the mother spacecraft to make a close flyby for scientific observations, which is difficult to be performed by the mother spacecraft if we consider the risk of the collision to the target asteroid or dust particles ejected from the asteroid. In order to utilize the large deep space maneuverability of the mother spacecraft, the CubeSat is retrieved by the mother spacecraft after the close flyby observation and it is carried to the next target asteroid to realize multiple asteroids flyby exploration.

Behavior Prediction Tools Strengthen Nanoelectronics

NASA Technical Reports Server (NTRS)

2013-01-01

Several years ago, NASA started making plans to send robots to explore the deep, dark craters on the Moon. As part of these plans, NASA needed modeling tools to help engineer unique electronics to withstand extremely cold temperatures. According to Jonathan Pellish, a flight systems test engineer at Goddard Space Flight Center, "An instrument sitting in a shadowed crater on one of the Moon s poles would hover around 43 K", that is, 43 kelvin, equivalent to -382 F. Such frigid temperatures are one of the main factors that make the extreme space environments encountered on the Moon and elsewhere so extreme. Radiation is another main concern. "Radiation is always present in the space environment," says Pellish. "Small to moderate solar energetic particle events happen regularly and extreme events happen less than a handful of times throughout the 7 active years of the 11-year solar cycle." Radiation can corrupt data, propagate to other systems, require component power cycling, and cause a host of other harmful effects. In order to explore places like the Moon, Jupiter, Saturn, Venus, and Mars, NASA must use electronic communication devices like transmitters and receivers and data collection devices like infrared cameras that can resist the effects of extreme temperature and radiation; otherwise, the electronics would not be reliable for the duration of the mission.

KSC-2014-3226

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts tour the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left, are Apollo 11 astronaut Buzz Aldrin, Mark Geyer, Orion Program manager, and Scott Wilson, manager, production operations for the Orion Program. Also at the renaming ceremony were Apollo astronauts Michael Collins and Jim Lovell. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System. Orion is designed to take humans farther than they've ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3224

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, members of the Armstrong family pose for a portrait with an Apollo-era spacesuit following its unveiling in the lobby of the newly named Neil Armstrong Operations and Checkout Building. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are Armstrong's son Mark, his grandson Bryce, his son Rick and his granddaughter Lily. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

KSC-2014-3243

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo astronaut Michael Collins tours the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, accompanied by family members and friends. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3232

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts tour the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Viewing the Orion crew module stacked on top of the service module from left, are Kennedy Center Director Bob Cabana, Apollo 11 astronaut Michael Collins, Apollo astronaut Jim Lovell, Apollo 11 astronaut Buzz Aldrin, and NASA Administrator Charlie Bolden. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System. Orion is designed to take humans farther than they've ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3202

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, the family of Neil Armstrong poses for a group portrait in front of the refurbished Operations and Checkout Building. From left are Armstrong's son Mark, his former wife Janet, his granddaughter Lily, his son Rick and his grandson Bryce. Armstrong, an Apollo 11 astronaut, was the first person to set foot on the moon and for whom the facility is newly named. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3251

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, NASA Administrator Charles Bolden, left, signs a banner displaying the new name of the Operations and Checkout Building, as Apollo 11 moonwalker Buzz Aldrin prepares to sign. The banner signing followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3242

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo astronauts Jim Lovell, left, and Buzz Aldrin tour the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3239

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo 11 astronaut Michael Collins checks out some equipment during a tour of the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3227

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts tour the refurbished Operations and Checkout Building, newly named for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Leading the way at left is Kennedy Center Director Bob Cabana, Scott Wilson, manager, production operations for the Orion Program, and Apollo 11 astronaut Michael Collins. At right is Apollo 11 astronaut Buzz Aldrin, and Mark Geyer, Orion Program manager. The building's high bay is being used to support the agency's new Orion spacecraft, which will lift off atop the Space Launch System. Orion is designed to take humans farther than they've ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3225

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, members of the Armstrong family pose beside a plaque following its unveiling in the lobby of the newly named Neil Armstrong Operations and Checkout Building. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are Armstrong's son Mark, his former wife Janet, his son Rick, his grandson Bryce, and his granddaughter Lily. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

KSC-2014-3254

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- A banner displaying the new name of the Operations and Checkout Building at NASA's Kennedy Space Center in Florida is signed by Apollo astronauts and their families. The banner signing followed a ceremony renaming the refurbished building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. The Orion spacecraft is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. Orion's first flight will be Exploration Fight Test-1, planned for December 2014. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3253

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Family members of Apollo 11 astronaut Neil Armstrong sign a banner displaying the new name of the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. The banner signing followed a ceremony renaming the refurbished building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are Armstrong's son Rick, his grandson Bryce and his granddaughter Lily. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kevin O'Connell

KSC-2014-3222

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, Center Director Robert Cabana reads the inscription on a plaque to invited guests following its unveiling in the lobby of the newly named Neil Armstrong Operations and Checkout Building. NASA Administrator Charles Bolden is at his right. The facility has been renamed for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The unveiling was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Apollo 11 astronauts landed in the moon's Sea of Tranquility aboard the lunar module, Eagle, on July 20, 1969, as the command module, Columbia, orbited overhead. For more: http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission/ Photo credit: NASA/Kim Shiflett

From a Million Miles Away, NASA Camera Shows Moon Crossing Face of Earth

NASA Image and Video Library

2015-08-05

This animation shows images of the far side of the moon, illuminated by the sun, as it crosses between the DISCOVR spacecraft's Earth Polychromatic Imaging Camera (EPIC) camera and telescope, and the Earth - one million miles away. Credits: NASA/NOAA A NASA camera aboard the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the moon as it moved in front of the sunlit side of Earth last month. The series of test images shows the fully illuminated “dark side” of the moon that is never visible from Earth. The images were captured by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope on the DSCOVR satellite orbiting 1 million miles from Earth. From its position between the sun and Earth, DSCOVR conducts its primary mission of real-time solar wind monitoring for the National Oceanic and Atmospheric Administration (NOAA). Read more: www.nasa.gov/feature/goddard/from-a-million-miles-away-na... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

From a Million Miles Away, NASA Camera Shows Moon Crossing Face of Earth

NASA Image and Video Library

2017-12-08

This animation still image shows the far side of the moon, illuminated by the sun, as it crosses between the DISCOVR spacecraft's Earth Polychromatic Imaging Camera (EPIC) camera and telescope, and the Earth - one million miles away. Credits: NASA/NOAA A NASA camera aboard the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the moon as it moved in front of the sunlit side of Earth last month. The series of test images shows the fully illuminated “dark side” of the moon that is never visible from Earth. The images were captured by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope on the DSCOVR satellite orbiting 1 million miles from Earth. From its position between the sun and Earth, DSCOVR conducts its primary mission of real-time solar wind monitoring for the National Oceanic and Atmospheric Administration (NOAA). Read more: www.nasa.gov/feature/goddard/from-a-million-miles-away-na... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

LADEE in Lunar Orbit

NASA Image and Video Library

2013-09-04

An artist's concept showing the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft is seen orbiting the moon as it prepares to fire its maneuvering thrusters to maintain a safe orbital altitude. Credit: NASA Ames / Dana Berry ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

LADEE Fires Thrusters Artist's Concept

NASA Image and Video Library

2013-09-04

An artist's concept of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft firing its maneuvering thrusters in order to maintain a safe altitude as it orbits the moon. Credit: NASA Ames / Dana Berry ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Inventory of Multiring Basins on the Moon After the Clementine Mission

NASA Astrophysics Data System (ADS)

Spudis, P. D.

1995-09-01

Multi-ring basins (impact craters greater than 300 km in diameter, regardless of presently expressed morphology; [1, 2]) are of primary importance in the excavation and redistribution of crustal materials and serve as the loci for the accumulation of extruded lavas on the Moon. Understanding their distribution and configuration is important in order to reconstruct the basin-forming impact [2]. The Clementine mission has made the first global maps of the Moon, including altimetry from a laser ranging experiment [3, 4]. This map permits the characterization of long-wavelength topographic features of the lunar crust, including the most prominent and important features, multi-ring basins. We have now surveyed the entire Moon with laser altimetry data from Clementine and have inventoried the global basin population. Many of the most obscure and degraded basins are strikingly expressed in the topographic data. Basins such as Mendel-Rydberg, a nearly obliterated ancient basin (600 km diameter, 5 km deep) south of Orientale, displays nearly as much relief as the "pristine" Orientale basin (900 km diameter; 7 km depth) [5]. The Fecunditatis basin, an obscure quasi-circular feature south of Mare Crisium [3], displays considerable topographic prominence, including an average relief of about 5 km. However, not all of the ancient basins are so deep: the Mutus-Vlacq basin [3], south of Nectaris, is clearly visible in the altimetry [5], but is only 1 to 1.5 km deep. Other basins that appear very ill-defined in the altimetry, yet clearly are present as regional depressions include the Australe, Tranquillitatis, and Margims basins [3]. That both relatively deep and shallow basins exist on the Moon is not surprising; what is remarkable is that there is no correlation between basin depth and geologic age. Apparently, basin morphology is more dependent on local conditions (e.g., crustal thickness, lithospheric conditions at the time of impact) than age. Another unusual expression of topography for a basin is that of the degraded Lomonosov-Fleming basin [3,6]. This feature appears as a quasi-circular, smooth plateau of nearly constant elevation about 500 km across. Such an expression is likely caused by infilling of the basin with ancient mare basalts, covered by highland plains and reexposed as the ejecta of dark halo impact craters [7,8]. This interpretation is supported by the mafic signature of the plains in this region in the Clementine global color image [9] and the presense of elevated amounts of iron in the highland crust here [10]. The altimetry data also show many depressions that are likely to be previously unrecognized basins. For example, depressions near the crater Darwin (20 degrees S, 70 degrees W; basin about 300 km diameter), eastern Mare Frigoris (55 degrees N, 30 degrees W; basin about 700 km across), and east of Mare Humboldtianum (60 degrees N, 130 degrees E; basin about 400 km diameter) are probably degraded impact basins. To date, over 45 basins and their rings have been mapped on the Moon and the relief and volumes of the basins have been measured. Work continues on the analysis of this numerical data, which should give insight into the processes of basin formation and planetary evolution. References: [1] Wilhelms D. E. (1987) USGS Prof. Pap. 1348, 302 pp. [2] Spudis P. D. (1993) Geology of Multi-Ring Impact Basins, Cambridge Univ., 263 pp. [3] Nozette S. et al. (1994) Science, 266, 1835. [4] Zuber M. T. et al. (1994) Science, 266, 1839. [5] Spudis P. D. et al. (1994) Science, 266, 1848. [6] Wilhelms D. and El-Baz F. (1977) USGS Map I-948. [7] Schultz P. H. and Spudis P. D. (1979) Proc. LPSC 10th, 2899. [8] Schultz P. H. and Spudis P. D. (1982) Nature, 302, 233. [9] Lucey P. G. et al. (1994) Science, 266, 1855. [10] Lucey P. G. et al. (1995) Science, 268, 1150.

Site Selection and Deployment Scenarios for Servicing of Deep-Space Observatories

NASA Technical Reports Server (NTRS)

Willenberg, Harvey J.; Fruhwirth, Michael A.; Potter, Seth D.; Leete, Stephen J.; Moe, Rud V.

2001-01-01

The deep-space environment and relative transportation accessibility of the Weak Stability Boundary (WSB) region connecting the Earth-Moon and Sun-Earth libration points makes the Sun-Earth L2 an attractive operating location for future observatories. A summary is presented of key characteristics of future observatories designed to operate in this region. The ability to service observatories that operate within the region around the Lagrange points may greatly enhance their reliability, lifetime, and scientific return. The range of servicing missions might begin with initial deployment, assembly, test, and checkout. Post-assembly servicing missions might also include maintenance and repair, critical fluids resupply, and instrument upgrades. We define the range of servicing missions that can be performed with extravehicular activity, with teleoperated robots, and with autonomous robots. We then describe deployment scenarios that affect payload design. A trade study is summarized of the benefits and risks of alternative servicing sites, including at the International Space Station, at other low-Earth-orbit locations, at the Earth-Moon L1 location, and on-site at the Sun-Earth L2 location. Required technology trades and development issues for observatory servicing at each site, and with each level of autonomy, are summarized.

Magnesian anorthosites and a deep crustal rock from the farside crust of the moon

NASA Astrophysics Data System (ADS)

Takeda, Hiroshi; Yamaguchi, A.; Bogard, D. D.; Karouji, Y.; Ebihara, M.; Ohtake, M.; Saiki, K.; Arai, T.

2006-07-01

Among over thirty lunar meteorites recovered from the hot deserts and Antarctica, Dhofar 489 is the most depleted in thorium (0.05 ppm), FeO, and rare earth elements (REE). Dhofar 489 is a crystalline matrix anorthositic breccia and includes clasts of magnesian anorthosites and a spinel troctolite. The Mg / (Mg + Fe) mol% (Mg numbers = 75-85) of olivine and pyroxene grains in this meteorite are higher than those of the Apollo ferroan anorthosites. Such materials were not recovered by the Apollo and Luna missions. However, remote sensing data suggest that the estimated concentrations of Th and FeO are consistent with the presence of such samples on the farside of the Moon. The differentiation trend deduced from the mineralogy of the anorthositic clasts define a magnesian extension of the ferroan anorthosite (FAN) trend constructed from the Apollo samples. The presence of magnesian anorthositic clasts in Dhofar 489 still offers a possibility that the farside trend with magnesian compositions is more primitive than the FAN trend, and may require a revision of this classical differentiation trend. The Ar-Ar age of Dhofar 489 is 4.23 ± 0.034 Gyr, which is older than most Ar ages reported for highland rocks returned by Apollo. The old Ar-Ar age of impact formation of this breccia and the presence of a fragment of spinel troctolite of deep crustal origin suggest that a basin forming event on the farside excavated the deep crust and magnesian anorthosites before formation of Imbrium.

Spatially Resolved Chemical Imaging for Biosignature Analysis: Terrestrial and Extraterrestrial Examples

NASA Astrophysics Data System (ADS)

Bhartia, R.; Wanger, G.; Orphan, V. J.; Fries, M.; Rowe, A. R.; Nealson, K. H.; Abbey, W. J.; DeFlores, L. P.; Beegle, L. W.

2014-12-01

Detection of in situ biosignatures on terrestrial and planetary missions is becoming increasingly more important. Missions that target the Earth's deep biosphere, Mars, moons of Jupiter (including Europa), moons of Saturn (Titan and Enceladus), and small bodies such as asteroids or comets require methods that enable detection of materials for both in-situ analysis that preserve context and as a means to select high priority sample for return to Earth. In situ instrumentation for biosignature detection spans a wide range of analytical and spectroscopic methods that capitalize on amino acid distribution, chirality, lipid composition, isotopic fractionation, or textures that persist in the environment. Many of the existing analytical instruments are bulk analysis methods and while highly sensitive, these require sample acquisition and sample processing. However, by combining with triaging spectroscopic methods, biosignatures can be targeted on a surface and preserve spatial context (including mineralogy, textures, and organic distribution). To provide spatially correlated chemical analysis at multiple spatial scales (meters to microns) we have employed a dual spectroscopic approach that capitalizes on high sensitivity deep UV native fluorescence detection and high specificity deep UV Raman analysis.. Recently selected as a payload on the Mars 2020 mission, SHERLOC incorporates these optical methods for potential biosignatures detection on Mars. We present data from both Earth analogs that operate as our only examples known biosignatures and meteorite samples that provide an example of abiotic organic formation, and demonstrate how provenance effects the spatial distribution and composition of organics.

How did the Lunar Magma Ocean crystallize?

NASA Astrophysics Data System (ADS)

Davenport, J.; Neal, C. R.

2012-12-01

It is generally accepted that the lunar crust and at least the uppermost (500 km) mantle was formed by crystallization of a magma ocean. How the magma ocean cooled and crystallized is still under debate. Parameters such as bulk composition, lunar magma ocean (LMO) crystallization method (fractional vs. equilibrium), depth of the LMO, and time for LMO solidification (effects of tidal heating mechanisms, insulating crustal lid, etc.) are still under debate. Neal (2001, JGR 106, 27865-27885) argues for the presence of garnet in the deep lunar mantle via compositional differences between low- and high-Ti mare basalts and volcanic glasses. Neal (2001) suggests that these compositional differences are due to the presence of garnet in the source regions of certain volcanic glass bead groups. As Neal (2001, JGR 106, 27865-27885) points out, determining if there is garnet in the lunar mantle is important in determining if the LMO was a "whole-Moon" event or if it was limited to certain areas. In the latter case, garnet would have been preserved in the lunar mantle and would have been used in the source material for some of the volcanic glasses. High-pressure experimental work concludes that with the right T-P conditions (2.5-4.5 GPa and 1675-1800° C) there could be a garnet-bearing pyroxene rich protolith at ~500 km depth. This also has significant implications for the bulk Al2O3 composition of the initial bulk Moon. If the LMO was not global, the volcanic glass beads that show evidence of garnet in their sources were formed from the deep, primitive lunar mantle, it begs the questions how was the non-LMO regions of the Moon formed and what was it's bulk composition? To try to answer these questions, it is necessary to thoroughly model the evolution of the LMO and then use that work to model the sources and formation of mare basalts, the volcanic glass beads, and other regions in question. To begin to answer these questions, we developed a scenario we have termed reverse LMO modeling. Geochemical compositions such as KREEP, ur-KREEP and FAN will be run backwards through various LMO models that have been proposed in the literature. The concentration of the initial bulk Moon, according to the concentrations of the particular type of rock being used, can be modeled by taking this from 0 percent liquid (PCL; a completely solidified Moon) to 100 PCL. Using the KREEP composition reported by Warren and Wasson (1979, Rev. of Geophysics and Space Physics 17, 73-88), Warren (1988, Proc. 18th LPSC, 233-241) and Warren (1989, LPI Tech. Report 89, 149-153), the Mg numbers (Mg#) for the bulk initial Moon were calculated yielding 0.87, 0.76, and 0.86 respectively. The major element compositions of calculated bulk Moon compositions have elevated Al2O3, FeO, and TiO2, consistent with the presence of garnet in the lunar mantle as well as generating high-Ti basalts. Using these data we can model the petrogenesis of the low- and high-Ti mare basalt and volcanic glass source regions. Furthermore, using remote sensing and the calculated source data we can compare the modeled concentrations of these rocks to where these ranges of concentrations fall on the Moon's surfaces, so that we can constrain the areas where the presence of a magma ocean on the Moon was possible.

Worlds Without Moons

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-04-01

Many of the exoplanets that weve discovered lie in compact systems with orbits very close to their host star. These systems are especially interesting in the case of cool stars where planets lie in the stars habitable zone as is the case, for instance, for the headline-making TRAPPIST-1 system.But other factors go into determining potential habitability of a planet beyond the rough location where water can remain liquid. One possible consideration: whether the planets have moons.Supporting HabitabilityLocations of equality between the Hill and Roche radius for five different potential moon densities. The phase space allows for planets of different semi-major axes and stellar host masses. Two example systems are shown, Kepler-80 and TRAPPIST-1, with dots representing the planets within them. [Kane 2017]Earths Moon is thought to have been a critical contributor to our planets habitability. The presence of a moon stabilizes its planets axial tilt, preventing wild swings in climate as the stars radiation shifts between the planets poles and equator. But what determines if a planet can have a moon?A planet can retain a moon in a stable orbit anywhere between an outer boundary of the Hill radius (beyond which the planets gravity is too weak to retain the moon) and an inner boundary of the Roche radius (inside which the moon would be torn apart by tidal forces). The locations of these boundaries depend on both the planets and moons properties, and they can be modified by additional perturbative forces from the host star and other planets in the system.In a new study, San Francisco State University scientist Stephen R. Kane modeled these boundaries for planets specifically in compact systems, to determine whether such planets can host moons to boost their likelihood of habitability.Allowed moon density as a function of semimajor axis for the TRAPPIST-1 system, for two different scenarios with different levels of perturbations. The vertical dotted lines show the locations of the six innermost TRAPPIST-1 planets. [Kane 2017]Challenge of Moons in Compact SystemsKane found that compact systems have a harder time supporting stable moons; the range of radii at which their moons can orbit is greatly reduced relative to spread-out systems like our own. As an example, Kane calculates that if the Earth were in a compact planetary system with a semimajor axis of 0.05 AU, its Hill radius would shrink from being 78.5 times to just 4.5 times its Roche radius greatly narrowing the region in which our Moon would be able to reside.Kane applied his models to the TRAPPIST-1 system as an example, demonstrating that its very unlikely that many if any of the systems seven planets would be able to retain a stable moon unless that moon were unreasonably dense.Is TRAPPIST-1 Really Moonless?Image of the Moon as it transits across the face of the Sun, as viewed from the Stereo-B spacecraft (which is in an Earth-trailing orbit). [NASA]How do these results fit with other observations of TRAPPIST-1? Kane uses our Moon as an example again: if we were watching a transit of the Earth and Moon in front of the Sun from a distance, the Moons transit depth would be 7.4% as deep as Earths. A transit of this depth in the TRAPPIST-1 system would have been detectable in Spitzer photometry of the system so the fact that we didnt see anything like this supports the idea that the TRAPPIST-1 planets dont have large moons.On the other hand, smaller moons (perhaps no more than 200300 km in radius) would have escaped detection. Future long-term monitoring of TRAPPIST-1 with observatories like the James Webb Space Telescope or 30-meter-class ground-based telescopes will help constrain this possibility, however.CitationStephen R. Kane 2017 ApJL 839 L19. doi:10.3847/2041-8213/aa6bf2

Coupling surface and mantle dynamics: A novel experimental approach

NASA Astrophysics Data System (ADS)

Kiraly, Agnes; Faccenna, Claudio; Funiciello, Francesca; Sembroni, Andrea

2015-05-01

Recent modeling shows that surface processes, such as erosion and deposition, may drive the deformation of the Earth's surface, interfering with deeper crustal and mantle signals. To investigate the coupling between the surface and deep process, we designed a three-dimensional laboratory apparatus, to analyze the role of erosion and sedimentation, triggered by deep mantle instability. The setup is constituted and scaled down to natural gravity field using a thin viscous sheet model, with mantle and lithosphere simulated by Newtonian viscous glucose syrup and silicon putty, respectively. The surface process is simulated assuming a simple erosion law producing the downhill flow of a thin viscous material away from high topography. The deep mantle upwelling is triggered by the rise of a buoyant sphere. The results of these models along with the parametric analysis show how surface processes influence uplift velocity and topography signals.

Decelerated invasion and waning-moon patterns in public goods games with delayed distribution.

PubMed

Szolnoki, Attila; Perc, Matjaž

2013-05-01

We study the evolution of cooperation in the spatial public goods game, focusing on the effects that are brought about by the delayed distribution of goods that accumulate in groups due to the continuous investments of cooperators. We find that intermediate delays enhance network reciprocity because of a decelerated invasion of defectors, who are unable to reap the same high short-term benefits as they do in the absence of delayed distribution. Long delays, however, introduce a risk because the large accumulated wealth might fall into the wrong hands. Indeed, as soon as the curvature of a cooperative cluster turns negative, the engulfed defectors can collect the heritage of many generations of cooperators and by doing so start a waning-moon pattern that nullifies the benefits of decelerated invasion. Accidental meeting points of growing cooperative clusters may also act as triggers for the waning-moon effect, thus linking the success of cooperators with their propensity to fail in a rather bizarre way. Our results highlight that "investing in the future" is a good idea only if that future is sufficiently near and not likely to be burdened by inflation.

NASA's Space Launch System: SmallSat Deployment to Deep Space

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Creech, Stephen D.

2017-01-01

Leveraging the significant capability it offers for human exploration and flagship science missions, NASA's Space Launch System (SLS) also provides a unique opportunity for lower-cost deep-space science in the form of small-satellite secondary payloads. Current plans call for such opportunities to begin with the rocket's first flight; a launch of the vehicle's Block 1 configuration, capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO), which will send the Orion crew vehicle around the moon and return it to Earth. On that flight, SLS will also deploy 13 CubeSat-class payloads to deep-space destinations. These secondary payloads will include not only NASA research, but also spacecraft from industry and international partners and academia. The payloads also represent a variety of disciplines including, but not limited to, studies of the moon, Earth, sun, and asteroids. While the SLS Program is making significant progress toward that first launch, preparations are already under way for the second, which will see the booster evolve to its more-capable Block 1B configuration, able to deliver 105t to LEO. That configuration will have the capability to carry large payloads co-manifested with the Orion spacecraft, or to utilize an 8.4-meter (m) fairing to carry payloads several times larger than are currently possible. The Block 1B vehicle will be the workhorse of the Proving Ground phase of NASA's deep-space exploration plans, developing and testing the systems and capabilities necessary for human missions into deep space and ultimately to Mars. Ultimately, the vehicle will evolve to its full Block 2 configuration, with a LEO capability of 130 metric tons. Both the Block 1B and Block 2 versions of the vehicle will be able to carry larger secondary payloads than the Block 1 configuration, creating even more opportunities for affordable scientific exploration of deep space. This paper will outline the progress being made toward flying smallsats on the first flight of SLS, and discuss future opportunities for smallsats on subsequent flights.

Microorganisms in extreme environments with a view to astrobiology in the outer solar system

NASA Astrophysics Data System (ADS)

Seckbach, Joseph; Chela-Flores, Julian

2015-09-01

We review the various manifestations of the evolution of life in extreme environments. We review those aspects of extremophiles that are most relevant for astrobiology. We are aware that geothermal energy triggering sources of heat in oceanic environments are not unique to our planet, a fact that was exposed by the Voyager mission images of volcanic activity on Io, the Jovian moon. Such activity exceeded by far what was known form terrestrial geology. The science of astrobiology has considered the possible presence of several moon oceans in the vicinity of both giant gas and icy planets. These watery environments include, not only Europa (strongly suggested by data from the Galileo mission), but the Voyager flybys exposed, not only the unusual geothermal activity on Io, but also the possible presence of subsurface oceans and some geothermal activity on the Neptune's moon Triton. More recently, calculations of Hussmann and coworkers with available data do not exclude that even Uranus moons may be candidates for bearing subsurface oceans. These possibilities invite a challenge that we gladly welcome, of preliminary discussions of habitability of extremophiles in so far novel environments for the science of astrobiology. Nevertheless, such exploration is currently believed to be feasible with the new generations of missions suggested for the time window of 2030 - 2040, or even earlier. We are envisaging, not only the current exploration of the moons of Saturn, but in the coming years we expect to go beyond to Uranus and Neptune to include dwarf planets and trans-neptunian worlds. Consequently, it is necessary to begin questioning whether the Europa-like conditions for the evolution of microorganisms are repeatable elsewhere. At present three new missions are in the process of being formulated, including the selection of payloads that will be necessary for the exploration of the various so far unexplored moons.

Shallow Lunar Seismic Activity and the Current Stress State of the Moon

NASA Technical Reports Server (NTRS)

Watters, Thomas R.; Weber, Renee C.; Collins, Geoffrey C.; Johnson, Catherine L.

2017-01-01

A vast, global network of more than 3200 lobate thrust fault scarps has been revealed in high resolution Lunar Reconnaissance Orbiter Camera (LROC) images. The fault scarps are very young, less than 50 Ma, based on their small scale and crisp appearance, crosscutting relations with small-diameter impact craters, and rates of infilling of associated small, shallow graben and may be actively forming today. The population of young thrust fault scarps provides a window into the recent stress state of the Moon and offers insight into the origin of global lunar stresses. The distribution of orientations of the fault scarps is non-random, inconsistent with isotropic stresses from late-stage global contraction as the sole source of stress. Modeling shows that tidal stresses contribute significantly to the current stress state of the lunar crust. Tidal stresses (orbital recession and diurnal tides) superimposed on stresses from global contraction result in non-isotropic compressional stress and may produce thrust faults consistent with lobate scarp orientations. At any particular point on the lunar surface, peak compressive stress will be reached at a certain time in the diurnal cycle. Coseismic slip events on currently active thrust faults are expected to be triggered when peak stresses are reached. Analysis of the timing of the 28 the shallow moonquakes recorded by the Apollo seismic network shows that 19 indeed occur when the Moon is closer to apogee, while only 9 shallow events occur when the Moon is closer to perigee. Here we report efforts to refine the model for the current stress state of the Moon by investigating the contribution of polar wander. Progress on relocating the epicentral locations of the shallow moonquakes using an algorithm designed for sparse networks is also reported.

Final Hazard Search

NASA Image and Video Library

2015-07-08

This single frame from a four-frame movie shows New Horizons' final deep search for hazardous material around Pluto, obtained on July 1, 2015. These data allow a highly sensitive search for any new moons. The images were taken with the spacecraft's Long Range Reconnaissance Imager (LORRI) over a 100-minute period, and were the final observations in the series of dedicated searches for hazards in the Pluto system which began on May 11. The images show all five known satellites of Pluto moving in their orbits around the dwarf planet, but analysis of these data has so far not revealed the existence of any additional moons. This means that any undiscovered Plutonian moons further than a few thousand miles from Pluto must be smaller than about 1 mile (1.6 kilometers) in diameter, if their surfaces have similar brightness to Pluto's big moon Charon. For comparison, Pluto's faintest known moon, Styx, which is conspicuous in the lower left quadrant of these images, is about 4 miles (7 kilometers) across, assuming the same surface brightness. The absence of additional moons, and also the absence of detectable rings in the hazard search data, imply that the spacecraft is very unlikely to be damaged by collisions with rings, or dust particles ejected from moons, during its high-speed passage through the Pluto system. The four movie frames were taken at 16:28, 16:38, 17:52, and 18:04 UTC on July 1, from a range of 9.4 million miles (15.2 million kilometers). Each frame is a mosaic of four sets of overlapping images, with a total exposure time of 120 seconds. The images have been heavily processed to remove the glare of Pluto and Charon, and the dense background of stars, though blemishes remain at the locations of many of the brighter stars. The "tails" extending to the right or downward from Pluto and Charon are camera artifacts caused by the extreme overexposure of both objects. Pluto and its five moons Charon, Styx, Nix, Kerberos and Hydra are identified by their initials, and their orbits around the center of gravity of the system (which is located just outside Pluto itself) are also shown. http://photojournal.jpl.nasa.gov/catalog/PIA19701

Evaluation of lunar regolith geopolymer binder as a radioactive shielding material for space exploration applications

NASA Astrophysics Data System (ADS)

Montes, Carlos; Broussard, Kaylin; Gongre, Matthew; Simicevic, Neven; Mejia, Johanna; Tham, Jessica; Allouche, Erez; Davis, Gabrielle

2015-09-01

Future manned missions to the moon will require the ability to build structures using the moon's natural resources. The geopolymer binder described in this paper (Lunamer) is a construction material that consists of up to 98% lunar regolith, drastically reducing the amount of material that must be carried from Earth in the event of lunar construction. This material could be used to fabricate structural panels and interlocking blocks that have radiation shielding and thermal insulation characteristics. These panels and blocks could be used to construct living quarters and storage facilities on the lunar surface, or as shielding panels to be installed on crafts launched from the moon surface to deep-space destinations. Lunamer specimens were manufactured in the laboratory and compressive strength results of up to 16 MPa when cast with conventional methods and 37 MPa when cast using uniaxial pressing were obtained. Simulation results have shown that the mechanical and chemical properties of Lunamer allow for adequate radiation shielding for a crew inside the lunar living quarters without additional requirements.

The Moon: Keystone to Understanding Planetary Geological Processes and History

NASA Technical Reports Server (NTRS)

2002-01-01

Extensive and intensive exploration of the Earth's Moon by astronauts and an international array of automated spacecraft has provided an unequaled data set that has provided deep insight into geology, geochemistry, mineralogy, petrology, chronology, geophysics and internal structure. This level of insight is unequaled except for Earth. Analysis of these data sets over the last 35 years has proven fundamental to understanding planetary surface processes and evolution, and is essential to linking surface processes with internal and thermal evolution. Much of the understanding that we presently have of other terrestrial planets and outer planet satellites derives from the foundation of these data. On the basis of these data, the Moon is a laboratory for understanding of planetary processes and a keystone for providing evolutionary perspective. Important comparative planetology issues being addressed by lunar studies include impact cratering, magmatic activity and tectonism. Future planetary exploration plans should keep in mind the importance of further lunar exploration in continuing to build solid underpinnings in this keystone to planetary evolution. Examples of these insights and applications to other planets are cited.

Goldstone Solar System Radar (GSSR)

NASA Technical Reports Server (NTRS)

Renzetti, N. A.

1991-01-01

The primary objective of the Goldstone Solar System Radar is the investigation of solar system bodies by means of Earth-based radar. Targets of primary interest include the Galilean moons, Saturn's rings and moons, and Earth-approaching asteroids and comets. Planets are also of interest, particularly Mercury and the planets to which NASA has not yet planned spacecraft visits. Based on a history of solid achievement, including the definition of the Astronomical Unit, imaging and topography of Mars, Venus, and Mercury, and contributions to the general theory of relativity, the program will continue to support flight project requirements and its primary objectives. The individual target objectives are presented, and information on the following topics are presented in tabular form: Deep Space Network support, compatibility tests, telemetry, command, and tracking support responsibility.

Properties of the Lunar Interior: Preliminary Results from the GRAIL Mission

NASA Technical Reports Server (NTRS)

Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.;

ESA SMART-1 mission: results and lessons for future lunar exploration

NASA Astrophysics Data System (ADS)

Foing, Bernard H.

We review ESA’s SMART-1 highlights and legacy 10 years after launch. We discuss lessons for future lunar exploration and upcoming missions. The SMART-1 mission to the Moon achieved record firsts such as: 1) first Small Mission for Advanced Research and Technology; with spacecraft built and integrated in 2.5 years and launched 3.5 years after mission approval; 2) first mission leaving the Earth orbit using solar power alone with demonstration for future deep space missions such as BepiColombo; 3) most fuel effective mission (60 litres of Xenon) and longest travel (13 month) to the Moon!; 4) first ESA mission reaching the Moon and first European views of lunar poles; 5) first European demonstration of a wide range of new technologies: Li-Ion modular battery, deep-space communications in X- and Ka-bands, and autonomous positioning for navigation; 6) first lunar demonstration of an infrared spectrometer and of a Swept Charge Detector Lunar X-ray fluorescence spectrometer ; 7) first ESA mission with opportunity for lunar science, elemental geochemistry, surface mineralogy mapping, surface geology and precursor studies for exploration; 8) first controlled impact landing on the Moon with real time observations campaign; 9) first mission supporting goals of the ILEWG/COSPAR International Lunar Exploration Working Group in technical and scientific exchange, international collaboration, public and youth engagement; 10) first mission preparing the ground for ESA collaboration in Chandrayaan-1, Chang’ E1-2-3 and near-future landers, sample return and human lunar missions. The SMART-1 technology legacy is applicable to application geostationary missions and deep space missions using solar electric propulsion. The SMART-1 archive observations have been used to support scientific research and prepare subsequent lunar missions. Most recent SMART-1 results are relevant to topics on: 1) the study of properties of the lunar dust, 2) impact craters and ejecta, 3) the study of illumination, 4) observations and science from the Moon, 5) support to future missions, 6) identifying and characterising sites for exploration and exploitation. These results and legacy are relevant to the preparation for future missions, in particular in the frame of collaboration between Russia and ESA on upcoming landers and on a polar sample return. Also the results contribute to the preparation for a global robotic village and international lunar bases (consistent with ILEWG, COSPAR and Global Space Exploration roadmaps). Link: http://sci.esa.int/smart-1/ References and citations: http://scholar.google.nl/scholar?&q=smart-1+moon *We acknowledge ESA, member states, industry and institutes for their contribution, and the members of SMART-1 Teams: G.Racca and SMART-1 Project Team, O. Camino and SMART-1 Operations Team, D. Frew and SMART-1 STOC, B.H. Foing and STWT, B. Grieger, D. Koschny, J.-L. Josset, S. Beauvivre, M. Ellouzi, S. Peters, A. Borst, E. Martellato, M. Almeida, J.Volp, D. Heather, M. Grande, J. Huovelin, H.U. Keller, U. Mall, A. Nathues, A. Malkki, W. Schmidt, G. Noci, Z. Sodnik, B. Kellett, P. Pinet, S. Chevrel, P. Cerroni, M.C. de Sanctis, M.A. Barucci, S. Erard, D. Despan, K. Muinonen, V. Shevchenko, Y. Shkuratov, P. McMannamon, P. Ehrenfreund, C. Veillet, M. Burchell, other Co-Investigators, associated scientists, collaborators, students and colleagues

Formation of Iapetus' extreme albedo dichotomy by exogenically triggered thermal ice migration.

PubMed

Spencer, John R; Denk, Tilmann

2010-01-22

The extreme albedo asymmetry of Saturn's moon Iapetus, which is about 10 times as bright on its trailing hemisphere as on its leading hemisphere, has been an enigma for three centuries. Deposition of exogenic dark material on the leading side has been proposed as a cause, but this alone cannot explain the global shape, sharpness, and complexity of the transition between Iapetus' bright and dark terrain. We demonstrate that all these characteristics, and the asymmetry's large amplitude, can be plausibly explained by runaway global thermal migration of water ice, triggered by the deposition of dark material on the leading hemisphere. This mechanism is unique to Iapetus among the saturnian satellites because its slow rotation produces unusually high daytime temperatures and water ice sublimation rates for a given albedo.

LADEE Test

NASA Image and Video Library

2017-12-08

Engineers at NASA's Ames Research Center, Moffett Field, Calif., prepare NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) Observatory for acoustic environmental testing. Credit: NASA/Ames ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

LADEE Preparations

NASA Image and Video Library

2013-09-04

NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft being prepared in the clean room at Wallops Flight Facility. Credit: NASA ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Constraining the volatile budget of the lunar interior

NASA Astrophysics Data System (ADS)

Potts, N. J.; Bromiley, G. D.

2017-12-01

Measurements of volatiles (F, Cl, S, H2O) in a range of lunar samples confirm the presence of volatile material in lunar magmas. It remains unknown, however, where this volatile material is stored and when it was delivered to the Moon. On Earth, point defects within mantle olivine, and its high-pressure polymorphs, are thought to be the largest reservoir of volatile material. However, as volatiles have been cycled into and out of the Earth's mantle throughout geological time, via subduction and volcanism, this masks any original volatile signatures. As the Moon has no plate tectonics, it is expected that any volatile material present in the deep lunar interior would have been inherited during accretion and differentiation, providing insight into the delivery of volatiles to the early Earth-Moon system. Our aim was, therefore, to test the volatile storage capacity of the deep lunar mantle and determine mineral/melt partitioning for key volatiles. Experiments were performed in a primitive lunar mantle composition and run at relevant T, P, and at fO2 below the IW buffer. Experiments replicated the initial stages of LMO solidification with either olivine + melt, olivine + pyroxene + melt, or pyroxene + melt as the only phases present. Mineral-melt partition coefficients (Dx) derived for volatile material (F, Cl, S, H2O) vary significantly compared to those derived for terrestrial conditions. An order of magnitude more H2O was found to partition into lunar olivine compared to the terrestrial upper mantle. DF derived for lunar olivine are comparable to the highest terrestrial derived values whilst no Cl was found to partition into lunar olivine under these conditions. Furthermore, an inverse trend between DF and DOH hints towards coupled-substitution mechanisms between H and F under low-fO2/lunar bulk composition. These results suggest that if volatile material was present in the LMO a significant proportion could be partitioned into the lower lunar mantle. The implications of this are not only important for understanding the behaviour of volatiles during planetary differentiation but would impact any future seismic study of the Moon.

KSC-2014-3196

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts visiting Launch Pad 39B with their families and friends take a moment to enjoy the view. From left are Apollo astronaut Jim Lovell, Center Director Bob Cabana, Apollo 11 command module pilot Mike Collins, and Apollo 11 moonwalker Buzz Aldrin's son Andy Aldrin. The group is at Kennedy for a ceremony renaming the Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. The pad is being modified to support the agency's new Orion spacecraft which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Neil Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3241

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo astronauts and their families tour the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Here, from left, Apollo 11 command module pilot Michael Collins, Apollo 8 and Apollo 13 crew member Jim Lovell, and Apollo 11 moonwalker Buzz Aldrin share a light moment. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3240

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo astronauts and their families tour the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Here, from left, Apollo 11 astronaut Michael Collins, NASA Administrator Charles Bolden, and Apollo 8 and Apollo 13 crew member Jim Lovell share a light moment. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the moon landing. As the world watched, Neil Armstrong and Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

Smart pH-responsive upconversion nanoparticles for enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

PubMed

Wang, Sheng; Zhang, Lei; Dong, Chunhong; Su, Lin; Wang, Hanjie; Chang, Jin

2015-01-01

A smart pH-responsive photodynamic therapy system based on upconversion nanoparticle loaded PEG coated polymeric lipid vesicles (RB-UPPLVs) was designed and prepared. These RB-UPPLVs which are promising agents for deep cancer photodynamic therapy applications can achieve enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

Giant impactors - Plausible sizes and populations

NASA Technical Reports Server (NTRS)

Hartmann, William K.; Vail, S. M.

1986-01-01

The largest sizes of planetesimals required to explain spin properties of planets are investigated in the context of the impact-trigger hypothesis of lunar origin. Solar system models with different large impactor sources are constructed and stochastic variations in obliquities and rotation periods resulting from each source are studied. The present study finds it highly plausible that earth was struck by a body of about 0.03-0.12 earth masses with enough energy and angular momentum to dislodge mantle material and form the present earth-moon system.

Operations Concepts for Deep-Space Missions: Challenges and Opportunities

NASA Technical Reports Server (NTRS)

McCann, Robert S.

2010-01-01

Historically, manned spacecraft missions have relied heavily on real-time communication links between crewmembers and ground control for generating crew activity schedules and working time-critical off-nominal situations. On crewed missions beyond the Earth-Moon system, speed-of-light limitations will render this ground-centered concept of operations obsolete. A new, more distributed concept of operations will have to be developed in which the crew takes on more responsibility for real-time anomaly diagnosis and resolution, activity planning and replanning, and flight operations. I will discuss the innovative information technologies, human-machine interfaces, and simulation capabilities that must be developed in order to develop, test, and validate deep-space mission operations

The Lunar Space Tug: A sustainable bridge between low Earth orbits and the Cislunar Habitat

NASA Astrophysics Data System (ADS)

Mammarella, M.; Paissoni, C. A.; Viola, N.; Denaro, A.; Gargioli, E.; Massobrio, F.

2017-09-01

The International Space Station is the first space human outpost and over the last 15 years, it has represented a peculiar environment where science, technology and human innovation converge together in a unique microgravity and space research laboratory. With the International Space Station entering the second part of its life and its operations running steadily at nominal pace, the global space community is starting planning how the human exploration could move further, beyond Low-Earth-Orbit. According to the Global Exploration Roadmap, the Moon represents the next feasible path-way for advances in human exploration towards the nal goal, Mars. Based on the experience of the ISS, one of the most widespread ideas is to develop a Cislunar Station in preparation of long duration missions in a deep space environment. Cislunar space is de ned as the area of deep space under the influence of Earth-Moon system, including a set of special orbits, e.g. Earth-Moon Libration points and Lunar Retrograde Orbit. This habitat represents a suitable environment for demonstrating and testing technologies and capabilities in deep space. In order to achieve this goal, there are several crucial systems and technologies, in particular related to transportation and launch systems. The Orion Multi-Purpose Crew Vehicle is a reusable transportation capsule designed to provide crew transportation in deep space missions, whereas NASA is developing the Space Launch System, the most powerful rocket ever built, which could provide the necessary heavy-lift launch capability to support the same kind of missions. These innovations would allow quite-fast transfers from Earth to the Cislunar Station and vice versa, both for manned and unmanned missions. However, taking into account the whole Concept of Operations for both the growth and sustainability of the Cislunar Space Station, the Lunar Space Tug can be considered as an additional, new and fundamental element for the mission architecture. The Lunar Space Tug represents an alternative to the SLS scenario, especially for what concerns all unmanned or logistic missions (e.g. cargo transfer, on orbit assembly, samples return), from Low Earth Orbit to Cislunar space. The paper focuses on the mission analysis and conceptual design of the Lunar Space Tug to support the growth and sustainment of the Cislunar Station. Particular attention is dedicated to the analysis of the propulsion subsystem effects of the Lunar Space Tug design. Main results are presented and discussed, and main conclusions are drawn.

Ultra High Voltage Propellant Isolators and Insulators for JIMO Ion Thrusters

NASA Technical Reports Server (NTRS)

Banks, Bruce A.; Gaier, James R.; Hung, Ching-Cheh; Walters, Patty A.; Sechkar, Ed; Panko, Scott; Kamiotis, Christina A.

2004-01-01

Within NASA's Project Prometheus, high specific impulse ion thrusters for electric propulsion of spacecraft for the proposed Jupiter Icy Moon Orbiter (JIMO) mission to three of Jupiter's moons: Callisto, Ganymede and Europa will require high voltage operation to meet mission propulsion. The anticipated approx.6,500 volt net ion energy will require electrical insulation and propellant isolation which must exceed that used successfully by the NASA Solar Electric Propulsion Technology Readiness (NSTAR) Deep Space 1 mission thruster by a factor of approx.6. Xenon propellant isolator prototypes that operate at near one atmosphere and prototypes that operate at low pressures (<100 Torr) have been designed and are being tested for suitability to the JIMO mission requirements. Propellant isolators must be durable to Paschen breakdown, sputter contamination, high temperature, and high voltage while operating for factors longer duration than for the Deep Space 1 Mission. Insulators used to mount the thrusters as well as those needed to support the ion optics have also been designed and are under evaluation. Isolator and insulator concepts, design issues, design guidelines, fabrication considerations and performance issues are presented. The objective of the investigation was to identify candidate isolators and insulators that are sufficiently robust to perform durably and reliably during the proposed JIMO mission.

Context odor presentation during sleep enhances memory in honeybees.

PubMed

Zwaka, Hanna; Bartels, Ruth; Gora, Jacob; Franck, Vivien; Culo, Ana; Götsch, Moritz; Menzel, Randolf

2015-11-02

Sleep plays an important role in stabilizing new memory traces after learning [1-3]. Here we investigate whether sleep's role in memory processing is similar in evolutionarily distant species and demonstrate that a context trigger during deep-sleep phases improves memory in invertebrates, as it does in humans. We show that in honeybees (Apis mellifera), exposure to an odor during deep sleep that has been present during learning improves memory performance the following day. Presentation of the context odor during wake phases or novel odors during sleep does not enhance memory. In humans, memory consolidation can be triggered by presentation of a context odor during slow-wave sleep that had been present during learning [3-5]. Our results reveal that deep-sleep phases in honeybees have the potential to prompt memory consolidation, just as they do in humans. This study provides strong evidence for a conserved role of sleep-and how it affects memory processes-from insects to mammals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Results from the Galileo Laser Uplink: A JPL Demonstration of Deep-Space Optical Communications

NASA Technical Reports Server (NTRS)

Wilson, K. E.; Lesh, J. R.

1993-01-01

The successful completion of the Galileo Optical Experiment (GOPEX), represented the accomplishment of a significant milestone in JPL's optical communication plan. The experiment demonstrated the first transmission of a narrow laser beam to a deep-space vehicle. Laser pulses were beamed to the Galileo spacecraft by Earth-based transmitters at the Table Mountain Facility (TMF), California, and Starfire Optical Range (SOR), New Mexico. The experiment took place over an eight-day period (December 9 through December 16, 1992) as Galileo receded from Earth on its way to Jupiter, and covered ranges from 1 to 6 million kilometers (15 times the Earth-Moon distance), the laser uplink from TMF covered the longest known range for laser beam transmission and detection. This demonstration is the latest in a series of accomplishments by JPL in the development of deep-space optical communications technology.

Evidence for infragravity wave-tide resonance in deep oceans.

PubMed

Sugioka, Hiroko; Fukao, Yoshio; Kanazawa, Toshihiko

2010-10-05

Ocean tides are the oscillatory motions of seawater forced by the gravitational attraction of the Moon and Sun with periods of a half to a day and wavelengths of the semi-Pacific to Pacific scale. Ocean infragravity (IG) waves are sea-surface gravity waves with periods of several minutes and wavelengths of several dozen kilometres. Here we report the first evidence of the resonance between these two ubiquitous phenomena, mutually very different in period and wavelength, in deep oceans. The evidence comes from long-term, large-scale observations with arrays of broadband ocean-bottom seismometers located at depths of more than 4,000 m in the Pacific Ocean. This observational evidence is substantiated by a theoretical argument that IG waves and the tide can resonantly couple and that such coupling occurs over unexpectedly wide areas of the Pacific Ocean. Through this resonant coupling, some of ocean tidal energy is transferred in deep oceans to IG wave energy.

Exomoon habitability constrained by illumination and tidal heating.

PubMed

Heller, René; Barnes, Rory

2013-01-01

The detection of moons orbiting extrasolar planets ("exomoons") has now become feasible. Once they are discovered in the circumstellar habitable zone, questions about their habitability will emerge. Exomoons are likely to be tidally locked to their planet and hence experience days much shorter than their orbital period around the star and have seasons, all of which works in favor of habitability. These satellites can receive more illumination per area than their host planets, as the planet reflects stellar light and emits thermal photons. On the contrary, eclipses can significantly alter local climates on exomoons by reducing stellar illumination. In addition to radiative heating, tidal heating can be very large on exomoons, possibly even large enough for sterilization. We identify combinations of physical and orbital parameters for which radiative and tidal heating are strong enough to trigger a runaway greenhouse. By analogy with the circumstellar habitable zone, these constraints define a circumplanetary "habitable edge." We apply our model to hypothetical moons around the recently discovered exoplanet Kepler-22b and the giant planet candidate KOI211.01 and describe, for the first time, the orbits of habitable exomoons. If either planet hosted a satellite at a distance greater than 10 planetary radii, then this could indicate the presence of a habitable moon.

A Model for the Thermal and Chemical Evolution of the Moon's Interior: Implications for the Onset of Mare Volcanism

NASA Technical Reports Server (NTRS)

Hess, Paul C.; Parmentier, E. M.

1995-01-01

Crystallization of the lunar magma ocean creates a chemically stratified Moon consisting of an anorthositic crust and magma ocean cumulates overlying the primitive lunar interior. Within the magma ocean cumulates the last liquids to crystallize form dense, ilmenite-rich cumulates that contain high concentrations of incompatible radioactive elements. The underlying olivine-orthopyroxene cumulates are also stratified with later crystallized, denser, more Fe-rich compositions at the top. This paper explores the chemical and thermal consequences of an internal evolution model accounting for the possible role of these sources of chemical buoyancy. Rayleigh-Taylor instability causes the dense ilmenite-rich cumulate layer and underlying Fe-rich cumulates to sink toward the center of the Moon, forming a dense lunar core. After this overturn, radioactive heating within the ilmenite-rich cumulate core heats the overlying mantle, causing it to melt. In this model, the source region for high-TiO2 mare basalts is a convectively mixed layer above the core-mantle boundary which would contain small and variable amounts of admixed ilmenite and KREEP. This deep high-pressure melting, as required for mare basalts, occurs after a reasonable time interval to explain the onset of mare basalt volcanism if the content of radioactive elements in the core and the chemical density gradients above the core are sufficiently high but within a range of values that might have been present in the Moon. Regardless of details implied by particular model parameters, gravitational overturn driven by the high density of magma ocean Fe-rich cumulates should concentrate high-TiO2 mare basalt sources, and probably a significant fraction of radioactive heating, toward the center of the Moon. This will have important implications for both the thermal evolution of the Moon and for mare basalt genesis.

LADEE Encapsulated in the Fairing

NASA Image and Video Library

2013-09-04

Engineers at NASA's Wallops Flight Facility in Virginia prepare to encapsulate the LADEE spacecraft into the fairing of the Minotaur V launch vehicle nose-cone. Credit: NASA/Wallops/Terry Zaperach ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Popular belief meets surgical reality: impact of lunar phases, Friday the 13th and zodiac signs on emergency operations and intraoperative blood loss.

PubMed

Schuld, Jochen; Slotta, Jan E; Schuld, Simone; Kollmar, Otto; Schilling, Martin K; Richter, Sven

2011-09-01

The influence of superstition, moon calendars, and popular belief on evidence-based medicine is stunning. More than 40% of medical staff is convinced that lunar phases can affect human behavior. The idea that Friday the 13th is associated with adverse events and bad luck is deep-rooted in the population of Western industrial countries. The aim of the present study was to test the hypothesis that these myths are transferable to real-life surgery. We analyzed the extent to which moon phases, zodiac signs, and Friday the 13th influence blood loss, emergency frequency, and intestinal perforations by evaluating the operation records of all 27,914 consecutive patients of our institution undergoing general, visceral, or vascular surgery between August 2001 and August 2010. Dates of surgery were allocated to lunar phases and to zodiac signs, as well as to Friday the 13th. A total of 111 lunar cycles and 15 Fridays the 13th occurred within the 3,281-day observation period. Patients' characteristics did not differ in lunar phases, zodiac signs, or Fridays the 13th. Full moon phases, the presence of Friday the 13th, and zodiac signs influenced neither intraoperative blood loss nor emergency frequency. No statistical peaks regarding perforated aortic aneurysms and gastrointestinal perforations were found on full moon or Friday the 13th. Scientific analysis of our data does not support the belief that moon phases, zodiac signs, or Friday 13th influence surgical blood loss and emergency frequency. Our data indicate that such beliefs are myths far beyond reality.

Orbital Perturbations of the Galilean Satellites during Planetary Encounters

NASA Astrophysics Data System (ADS)

Deienno, Rogerio; Nesvorný, David; Vokrouhlický, David; Yokoyama, Tadashi

2014-08-01

The Nice model of the dynamical instability and migration of the giant planets can explain many properties of the present solar system, and can be used to constrain its early architecture. In the jumping-Jupiter version of the Nice model, required from the terrestrial planet constraint and dynamical structure of the asteroid belt, Jupiter has encounters with an ice giant. Here, we study the survival of the Galilean satellites in the jumping-Jupiter model. This is an important concern because the ice-giant encounters, if deep enough, could dynamically perturb the orbits of the Galilean satellites and lead to implausible results. We performed numerical integrations where we tracked the effect of planetary encounters on the Galilean moons. We considered three instability cases from Nesvorný & Morbidelli that differed in the number and distribution of encounters. We found that in one case, where the number of close encounters was relatively small, the Galilean satellite orbits were not significantly affected. In the other two, the orbital eccentricities of all moons were excited by encounters, Callisto's semimajor axis changed, and, in a large fraction of trials, the Laplace resonance of the inner three moons was disrupted. The subsequent evolution by tides damps eccentricities and can recapture the moons in the Laplace resonance. A more important constraint is represented by the orbital inclinations of the moons, which can be excited during the encounters and not appreciably damped by tides. We find that one instability case taken from Nesvorný & Morbidelli clearly does not meet this constraint. This shows how the regular satellites of Jupiter can be used to set limits on the properties of encounters in the jumping-Jupiter model, and help us to better understand how the early solar system evolved.

Thorium abundances of basalt ponds in South Pole-Aitken basin: Insights into the composition and evolution of the far side lunar mantle

USGS Publications Warehouse

Hagerty, Justin J.; Lawrence, D.J.; Hawke, B.R.

2011-01-01

Imbrian-aged basalt ponds, located on the floor of South Pole-Aitken (SPA) basin, are used to provide constraints on the composition and evolution of the far side lunar mantle. We use forward modeling of the Lunar Prospector Gamma Ray Spectrometer thorium data, to suggest that at least five different and distinct portions of the far side lunar mantle contain little or no thorium as of the Imbrian Period. We also use spatial correlations between local thorium enhancements and nonmare material on top of the basalt ponds to support previous assertions that lower crustal materials exposed in SPA basin have elevated thorium abundances, consistent with noritic to gabbronoritic lithologies. We suggest that the lower crust on the far side of the Moon experienced multiple intrusions of thorium-rich basaltic magmas, prior to the formation of SPA basin. The fact that many of the ponds on the lunar far side have elevated titanium abundances indicates that the far side of the Moon experienced extensive fractional crystallization that likely led to the formation of a KREEP-like component. However, because the Imbrian-aged basalts contain no signs of elevated thorium, we propose that the SPA impact event triggered the transport of a KREEP-like component from the lunar far side and concentrated it on the nearside of the Moon. Because of the correlation between basaltic ponds and basins within SPA, we suggest that Imbrian-aged basaltic volcanism on the far side of the Moon was driven by basin-induced decompressional melting.

Low-thrust trajectory optimization of asteroid sample return mission with multiple revolutions and moon gravity assists

NASA Astrophysics Data System (ADS)

Tang, Gao; Jiang, FanHuag; Li, JunFeng

2015-11-01

Near-Earth asteroids have gained a lot of interest and the development in low-thrust propulsion technology makes complex deep space exploration missions possible. A mission from low-Earth orbit using low-thrust electric propulsion system to rendezvous with near-Earth asteroid and bring sample back is investigated. By dividing the mission into five segments, the complex mission is solved separately. Then different methods are used to find optimal trajectories for every segment. Multiple revolutions around the Earth and multiple Moon gravity assists are used to decrease the fuel consumption to escape from the Earth. To avoid possible numerical difficulty of indirect methods, a direct method to parameterize the switching moment and direction of thrust vector is proposed. To maximize the mass of sample, optimal control theory and homotopic approach are applied to find the optimal trajectory. Direct methods of finding proper time to brake the spacecraft using Moon gravity assist are also proposed. Practical techniques including both direct and indirect methods are investigated to optimize trajectories for different segments and they can be easily extended to other missions and more precise dynamic model.

Human Assisted Robotic Vehicle Studies - A conceptual end-to-end mission architecture

NASA Astrophysics Data System (ADS)

Lehner, B. A. E.; Mazzotta, D. G.; Teeney, L.; Spina, F.; Filosa, A.; Pou, A. Canals; Schlechten, J.; Campbell, S.; Soriano, P. López

2017-11-01

With current space exploration roadmaps indicating the Moon as a proving ground on the way to human exploration of Mars, it is clear that human-robotic partnerships will play a key role for successful future human space missions. This paper details a conceptual end-to-end architecture for an exploration mission in cis-lunar space with a focus on human-robot interactions, called Human Assisted Robotic Vehicle Studies (HARVeSt). HARVeSt will build on knowledge of plant growth in space gained from experiments on-board the ISS and test the first growth of plants on the Moon. A planned deep space habitat will be utilised as the base of operations for human-robotic elements of the mission. The mission will serve as a technology demonstrator not only for autonomous tele-operations in cis-lunar space but also for key enabling technologies for future human surface missions. The successful approach of the ISS will be built on in this mission with international cooperation. Mission assets such as a modular rover will allow for an extendable mission and to scout and prepare the area for the start of an international Moon Village.

Stochastic events lead to accretion in Saturn’s rings

NASA Astrophysics Data System (ADS)

Esposito, L. W.

2009-12-01

UVIS occultations indicate accretion is triggered at the B ring edge, in strong density waves in ring A and in the F ring. Moons may trigger accretion by streamline crowding (Lewis & Stewart); which enhances collisions, leading to accretion; increasing random velocities; leading to more collisions and more accretion. Cassini occultations of these strongly perturbed locations show not only accretion but also disaggregation, with time scales of hours to weeks. The collisions may lead to temporary aggregations via stochastic events: they can compress unconsolidated objects, trigger adhesion or bring small pieces into contact with larger or higher-density seeds. Disaggregation then can follow from disruptive collisions or tidal shedding. In the accretion/disruption balance, increased random motions could eventually give the upper hand to disruption… just as ‘irrational exuberance’ can lead to financial panic in the economy; or the overpopulation of hares can lead to boom-and-bust in the population of foxes. This unstable equilibrium can similarly give rise to episodic cycles in accretion: explaining why the observable ring features that indicate embedded objects have been increasing since the beginning of Cassini’s observations of Saturn in 2004.

Stochastic events lead to accretion in Saturn's rings

NASA Astrophysics Data System (ADS)

Esposito, Larry W.

2010-05-01

UVIS occultations indicate accretion is triggered at the B ring edge, in strong density waves in ring A and in the F ring. Moons may trigger accretion by streamline crowding (Lewis & Stewart); which enhances collisions, leading to accretion; increasing random velocities; leading to more collisions and more accretion. Cassini occultations of these strongly perturbed locations show not only accretion but also disaggregation, with time scales of hours to weeks. The collisions may lead to temporary aggregations via stochastic events: collisions can compress unconsolidated objects, trigger adhesion or bring small pieces into contact with larger or higher-density seeds. Disaggregation then can follow from disruptive collisions or tidal shedding. In the accretion/disruption balance, increased random motions could eventually give the upper hand to disruption… just as ‘irrational exuberance' can lead to financial panic in the economy; or the overpopulation of hares can lead to boom-and-bust in the population of foxes. This unstable equilibrium can similarly give rise to episodic cycles in accretion: explaining why the observable ring features that indicate embedded objects have been increasing since the beginning of Cassini's observations of Saturn in 2004.

Development and Testing of a Laser-Powered Cryobot for Outer Planet Icy Moon Exploration

NASA Astrophysics Data System (ADS)

Siegel, V.; Stone, W.; Hogan, B.; Lelievre, S.; Flesher, C.

2013-12-01

Project VALKYRIE (Very-deep Autonomous Laser-powered Kilowatt-class Yo-yoing Robotic Ice Explorer) is a NASA-funded effort to develop the first laser powered cryobot - a self-contained intelligent ice penetrator capable of delivering science payloads through ice caps of the outer planet icy moons. The long range objective is to enable a full-scale Europa lander mission in which an autonomous life-searching underwater vehicle is transported by the cryobot and launched into the sub-surface Europan ocean. Mission readiness testing will involve an Antarctic sub-glacial lake cryobot sample return through kilometers of ice cap thickness. A key element of VALKYRIE's design is the use of a high energy laser as the primary power source. 1070 nm laser light is transmitted at a power level of 5 kW from a surface-based laser and injected into a custom-designed optical waveguide that is spooled out from the descending cryobot. Light exits the downstream end of the fiber, travels through diverging optics, and strikes a beam dump, which channels thermal power to hot water jets that melt the descent hole. Some beam energy is converted, via photovoltaic cells, to electricity for running onboard electronics and jet pumps. Since the vehicle can be sterilized prior to deployment and the melt path freezes behind it, preventing forward contamination, expansions on VALKYRIE concepts may enable cleaner and faster access to sub-glacial Antarctic lakes. Testing at Stone Aerospace between 2010 and 2013 has already demonstrated high power optical energy transfer over relevant (kilometer scale) distances as well as the feasibility of a vehicle-deployed optical waveguide (through which the power is transferred). The test vehicle is equipped with a forward-looking synthetic aperture radar (SAR) that can detect obstacles out to 1 kilometer from the vehicle. The initial ASTEP test vehicle will carry a science payload consisting of a DUV flow cytometer and a water sampling sub-system that will be triggered based on real-time analysis of the cytometer data. Results of laboratory test data and details of planned field campaigns will be discussed.

Analysis of selected deep space missions

NASA Technical Reports Server (NTRS)

West, W. S.; Holman, M. L.; Bilsky, H. W.

1971-01-01

Task 1 of the NEW MOONS (NASA Evaluation With Models of Optimized Nuclear Spacecraft) study is discussed. Included is an introduction to considerations of launch vehicles, spacecraft, spacecraft subsystems, and scientific objectives associated with precursory unmanned missions to Jupiter and thence out of the ecliptic plane, as well as other missions to Jupiter and other outer planets. Necessity for nuclear power systems is indicated. Trajectories are developed using patched conic and n-body computer techniques.

Solar Warning Architecture for Manned Missions to Mars

DTIC Science & Technology

2011-06-01

public discussions of manned missions to return to the Moon, explore near-earth asteroids , and even visit Mars, a deep-space solar weather warning...mission planning, and libration points. In addition, the limited previous analysis on this problem was mined for information. 2.2 Radiation Effects...behind the Earth, on its orbital path. These two libration points are stable along all 3 axes, leading some to theorize there may be asteroids or

An Integrated Science Glovebox for the Gateway Habitat

NASA Technical Reports Server (NTRS)

Calaway, M. J.; Evans, C. A.; Garrison, D. H.; Bell, M. S.

2018-01-01

Next generation habitats for deep space exploration of cislunar space, the Moon, and ultimately Mars will benefit from on-board glovebox capability. Such a glovebox facility will maintain sample integrity for a variety of scientific endeavors whether for life science, materials science, or astromaterials. Glovebox lessons learned from decades of astromaterials curation, ISS on-board sample handling, and robust analog missions provide key design and operational factors for inclusion in on-going habitat development.

Modified-Fibonacci-Dual-Lucas method for earthquake prediction

NASA Astrophysics Data System (ADS)

Boucouvalas, A. C.; Gkasios, M.; Tselikas, N. T.; Drakatos, G.

2015-06-01

The FDL method makes use of Fibonacci, Dual and Lucas numbers and has shown considerable success in predicting earthquake events locally as well as globally. Predicting the location of the epicenter of an earthquake is one difficult challenge the other being the timing and magnitude. One technique for predicting the onset of earthquakes is the use of cycles, and the discovery of periodicity. Part of this category is the reported FDL method. The basis of the reported FDL method is the creation of FDL future dates based on the onset date of significant earthquakes. The assumption being that each occurred earthquake discontinuity can be thought of as a generating source of FDL time series The connection between past earthquakes and future earthquakes based on FDL numbers has also been reported with sample earthquakes since 1900. Using clustering methods it has been shown that significant earthquakes (<6.5R) can be predicted with very good accuracy window (+-1 day). In this contribution we present an improvement modification to the FDL method, the MFDL method, which performs better than the FDL. We use the FDL numbers to develop possible earthquakes dates but with the important difference that the starting seed date is a trigger planetary aspect prior to the earthquake. Typical planetary aspects are Moon conjunct Sun, Moon opposite Sun, Moon conjunct or opposite North or South Modes. In order to test improvement of the method we used all +8R earthquakes recorded since 1900, (86 earthquakes from USGS data). We have developed the FDL numbers for each of those seeds, and examined the earthquake hit rates (for a window of 3, i.e. +-1 day of target date) and for <6.5R. The successes are counted for each one of the 86 earthquake seeds and we compare the MFDL method with the FDL method. In every case we find improvement when the starting seed date is on the planetary trigger date prior to the earthquake. We observe no improvement only when a planetary trigger coincided with the earthquake date and in this case the FDL method coincides with the MFDL. Based on the MDFL method we present the prediction method capable of predicting global events or localized earthquakes and we will discuss the accuracy of the method in as far as the prediction and location parts of the method. We show example calendar style predictions for global events as well as for the Greek region using planetary alignment seeds.

Earth's rotation variations and earthquakes 2010-2011

NASA Astrophysics Data System (ADS)

Ostřihanský, L.

2012-01-01

In contrast to unsuccessful searching (lasting over 150 years) for correlation of earthquakes with biweekly tides, the author found correlation of earthquakes with sidereal 13.66 days Earth's rotation variations expressed as length of a day (LOD) measured daily by International Earth's Rotation Service. After short mention about earthquakes M 8.8 Denali Fault Alaska 3 November 2002 triggered on LOD maximum and M 9.1 Great Sumatra earthquake 26 December 2004 triggered on LOD minimum and the full Moon, the main object of this paper are earthquakes of period 2010-June 2011: M 7.0 Haiti (12 January 2010 on LOD minimum, M 8.8 Maule Chile 12 February 2010 on LOD maximum, map constructed on the Indian plate revealing 6 earthquakes from 7 on LOD minimum in Sumatra and Andaman Sea region, M 7.1 New Zealand Christchurch 9 September 2010 on LOD minimum and M 6.3 Christchurch 21 February 2011 on LOD maximum, and M 9.1 Japan near coast of Honshu 11 March 2011 on LOD minimum. It was found that LOD minimums coincide with full or new Moon only twice in a year in solstices. To prove that determined coincidences of earthquakes and LOD extremes stated above are not accidental events, histograms were constructed of earthquake occurrences and their position on LOD graph deeply in the past, in some cases from the time the IERS (International Earth's Rotation Service) started to measure the Earth's rotation variations in 1962. Evaluations of histograms and the Schuster's test have proven that majority of earthquakes are triggered in both Earth's rotation deceleration and acceleration. Because during these coincidences evident movements of lithosphere occur, among others measured by GPS, it is concluded that Earth's rotation variations effectively contribute to the lithospheric plates movement. Retrospective overview of past earthquakes revealed that the Great Sumatra earthquake 26 December 2004 had its equivalent in the shape of LOD graph, full Moon position, and character of aftershocks 19 years earlier in difference only one day to 27 December 1985 earthquake, proving that not only sidereal 13.66 days variations but also that the 19 years Metons cycle is the period of the earthquakes occurrence. Histograms show the regular change of earthquake positions on branches of LOD graph and also the shape of histogram and number of earthquakes on LOD branches from the mid-ocean ridge can show which side of the ridge moves quicker.

Trajectory Design and Orbital Dynamics of Deep Space Exploration

NASA Astrophysics Data System (ADS)

Zhao, Y. H.

2013-05-01

The term of deep space exploration is used for the exploration in which a probe, unlike an earth satellite, escapes from the Earth's gravitation field, and conducts the exploration of celestial bodies within or away from the solar system. As the progress of aerospace science and technology, the exploration of the Moon and other planets of the solar system has attracted more and more attention throughout the world since late 1990s. China also accelerated its progress of the lunar exploration in recent years. Its first lunar-orbiting spacecraft, Chang'e 1, was successfully launched on 2007 October 24. It then achieved the goals of accurate maneuver and lunar orbiting, acquired a large amount of scientific data and a full lunar image, and finally impacted the Moon under control. On 2010 October 1, China launched Chang'e 2 with success, which obtained a full lunar image with a higher resolution and a high-definition image of the Sinus Iridum, and completed multiple extended missions such as orbiting the Lagrangian point L2, laying the groundwork for future deep space exploration. As the first phase of the three main operational phases (orbiting, landing, return) of the Chinese Lunar Exploration Program, the successful launches and flights of Chang'e 1 and Chang'e 2 are excellent applications of the orbit design of both the Earth-Moon transfer orbit and the circumlunar orbit, yet not involving the design of the entire trajectory consisting of the Earth-Moon transfer orbit, the circumlunar orbit, and the return orbit, which is produced particularly for sample return spacecraft. This paper studies the entire orbit design of the lunar sample return spacecraft which would be employed in both the third phase of the lunar exploration program and the human lunar landing program, analyzes the dynamic characteristics of the orbit, and works out the launch windows based on specific conditions. The results are universally applicable, and could serve as the basis of the orbit design of the lunar sample return spacecraft. Meanwhile, China's independent Mars exploration is in progress. In this context, this paper also carries out comprehensive related researches, such as the orbit design and computation of the Earth-Mars transfer orbit, the selection of its launch window, and mid-course trajectory correction maneuver (TCM), etc. It conducts calculations and dynamic analysis for Hohmann transfer orbit in accurate dynamic model, providing basis for the selection and design of the transfer orbit in China's Mars exploration. On the basis of orbit dynamics theory of the small bodies including detectors in the solar system, all the works concerned about trajectory design in this paper are worked out in a complete and reasonable dynamic model, that is why the results have some referential value for the trajectory design in the deep space exploration. The major innovations in this paper are as follows: (1) This paper studies different types of the Earth-Moon transfer orbit on the basis of orbit dynamics theory of small bodies in the solar system, and provides the theoretical basis of the orbit type selection in practical missions; (2) This paper works on the orbit dynamics of the free return orbit, which intends to guarantee the safety of the astronauts in the human landing moon exploration, and carries out the free return orbit calculated in the real dynamic model; (3) This paper shows the characteristics of the reentry angle of the Moon-Earth transfer orbit. With the conditions of the landing range of our country taken into account, our works carry out the constraints of the reentry angle and the latitude of the explorer at reentry time, and provide the basis of orbit type choice for practical applications; (4) Based on the error transition matrix of the small bodies' motion, this paper analyzes the attributes of the error propagation of the Earth-Moon transfer orbit, on the basis of which it proposes the timing methods as well as the equation for the determination of the velocity increment for TCMs; (5) Based on the IAU2000 Mars orientation model, this paper studies the precession part of the change of Mars gravitation, which lays the foundation for further study of its influence on the Mars orbiter's orbit of precession. This paper proposes the analytical solution of the corresponding coordinate additional perturbations; (6) This paper studies the characteristics of the Earth-Mars transfer orbit in the real dynamic model, and puts forward the according theoretical analysis; (7) The theoretical analysis of the error propagation of the Earth-Mars transfer orbit is performed on the basis of error transition matrix, thereafter the determination of time and the calculation of velocity increment for TCMs are given. By comparing the results of different methods, it proves that the linear method of TCM calculation is the most timesaving one among all applicable methods for a certain accuracy requirement; (8) All the numerical simulations in the production of this paper are carried out by programs written on my own, which could apply to other relevant missions.

Preconditioning and Formation Mechanisms of Maud Rise (Open Ocean) Polynyas in a High-Resolution CESM Simulation

NASA Astrophysics Data System (ADS)

Kurtakoti, P. K.; Veneziani, C.; Stoessel, A.; Weijer, W.

2016-12-01

Processes responsible for preconditioning and formation of Maud Rise Polynyas (MRP) were analyzed within the framework of a high-resolution fully coupled Community Earth System Model (CESM) simulation. Open Ocean Polynyas (OOPs) are large ice-free areas within the winter ice pack. These are regions of deep convection and strong atmosphere-ice-ocean interaction through which they play an important role in the formation of bottom waters. The data analyzed comes from a simulation conducted in a pre-industrial scenario as part of the Accelerated Climate Modeling for Energy (ACME) project. Within this simulation, persistent winter OOPs were simulated in the Weddell Sea (Weddell Sea Polynya) and over the Maud Rise seamount (Maud Rise Polynya). The sea ice concentration in the Weddell Sea shows that MRP acts as a precondition to Weddell Sea polynyas, which is consistent with mid 1970s observations of a westward expansion of MRP into the Weddell Sea. The OOPs in years 30-40 of the CESM simulation are largely over Maud Rise giving us an opportunity to investigate processes that trigger and maintain the OOP in winter over Maud Rise. The heat content of the Weddell Deep Water (WDW) is seen to be an important factor for MRPs, consistent with previous studies. The first MRP in the 30s coincides with the strongest negative wind stress curl over the Weddell Sea, which implies that this condition is a triggering mechanism for deep convection. The deep convective event associated with the OOP leads to a reduction of deep ocean heat reservoir up to 3000m depth. The simulation captures a westward flow of WDW impinging on Maud Rise seamount. Previous studies suggest Taylor column dynamics to be necessary for MRPs to emerge. We have explored how Taylor column dynamics could contribute to preconditioning and triggering deep open ocean convection over Maud Rise Seamount. We also investigate the importance of resolution of bottom topography for the formation of a strong enough Taylor column over Maud Rise to interact with the pycnocline to the point that an OOP develops.

KSC-2014-3190

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center in Florida, NASA officials and Apollo astronauts visiting Launch Pad 39B with their families and friends preserve the moment with a group portrait. The group was at Kennedy for a ceremony renaming the Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are NASA Administrator Charles Bolden, Apollo astronaut Jim Lovell, Neil's son Mark Armstrong, Neil's granddaughter Lily Armstrong, Neil's son Rick Armstrong, Neil's grandson Bryce Armstrong, Neil's former wife Janet Armstrong, Apollo 11 moonwalker Buzz Aldrin, and Apollo 11 command module pilot Michael Collins. The pad is being modified to support the agency's new Orion spacecraft which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Neil Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

KSC-2014-3238

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- Apollo astronauts and their families tour the astronaut crew quarters in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. The tour followed a ceremony renaming the refurbished Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. Here, Armstrong's grandchildren, Bryce and Lily, in front, make their way into the room. Center Director Robert Cabana talks with Apollo 8 and Apollo 13 crew member Jim Lovell, at left, as NASA Administrator Charles Bolden talks with other Armstrong family members, at right. Besides housing the crew quarters, the building's high bay is being used to support the agency's new Orion spacecraft and is the same spaceport facility where the Apollo 11 command/service module and lunar module were prepped for the first lunar landing mission in 1969. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The ceremony was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Buzz Aldrin landed in the moon's Sea of Tranquility on July 20, 1969, aboard the lunar module Eagle. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

How cold pool triggers deep convection?

NASA Astrophysics Data System (ADS)

Yano, Jun-Ichi

2014-05-01

The cold pool in the boundary layer is often considered a major triggering mechanism of convection. Here, presented are basic theoretical considerations on this issue. Observations suggest that cold pool-generated convective cells is available for shallow maritime convection (Warner et al. 1979; Zuidema et al. 2012), maritime deep convection (Barnes and Garstang 1982; Addis et al. 1984; Young et al. 1995) and continental deep convection (e.g., Lima and Wilson 2008; Flamant 2009; Lothon et al. 2011; Dione et al. 2013). Moreover, numerical studies appear to suggest that cold pools promote the organization of clouds into larger structures and thereby aid the transition from shallow to deep convection (Khairoutdinov and Randall 2006, Boing et al. 2012, Schlemmer and Hohenegger, 2014). Even a cold--pool parameterization coupled with convection is already proposed (Grandpeix and Lafore 2010: but see also Yano 2012). However, the suggested link between the cold pool and deep convection so far is phenomenological at the best. A specific process that the cold pool leads to a trigger of deep convection must still to be pinned down. Naively, one may imagine that a cold pool lifts up the air at the front as it propagates. Such an uplifting leads to a trigger of convection. However, one must realize that a shift of air along with its propagation does not necessarily lead to an uplifting, and even if it may happen, it would not far exceed a depth of the cold pool itself. Thus, the uplifting can never be anything vigorous. Its thermodynamic characteristics do help much either for inducing convection. The cold-pool air is rather under rapid recovering process before it can induce convection under a simple parcel-lifting argument. The most likely reason that the cold pool may induce convection is its gust winds that may encounter an air mass from an opposite direction. This induces a strong convergence, also leading to a strong uplifting. This is an argument essentially developed by Moncrieff and Liu (1999). As a whole, in attempting a statistical description of boundary-layer processes, the cold pool is essentially nothing other than an additional contribution to a TKE (turbulent kinetic energy) budget. Significance of trigger of convection by cold pool in context of convection parameterization must also be seen with much caution. Against a common misunderstanding, current convection parameterization is not designed to describe a trigger process of individual convection. In this respect, process studies on cold pool do not contribute to improvements of convection parameterization until a well-defined parameterization formulation for individual convection processes is developed. Even before then a question should also be posed whether such a development is necessary. Under a current mass-flux convection parameterization, a more important process to consider is re-evaporative cooling of detrained cloudy air, which may also be associated with downdraft, possibly further leading to a generation of a cold pool. Yano and Plant (2012) suggest, from a point of view of the convective-energy cycle, what follows would be far less important than the fact the re-evaporation induces a generation of convective kinetic energy (though it may initially be considered TKE). Both well-focused convective process studies as well as convection parameterization formulation would be much needed.

Engines for the Cosmos

NASA Technical Reports Server (NTRS)

Rodgers, Stephen L.; Reisz, Al; Wyckoff, James (Technical Monitor)

2002-01-01

Galactic forces spiral across the cosmos fueled by nuclear fission and fusion and atoms in plasmatic states with throes of constraints of gravitational forces and magnetic fields, In their wanderings these galaxies spew light, radiation, atomic and subatomic particles throughout the universe. Throughout the ages of man visions of journeying through the stars have been wondered. If humans and human devices from Earth are to go beyond the Moon and journey into deep space, it must be accomplished with like forces of the cosmos such as electrical fields, magnetic fields, ions, electrons and energies generated from the manipulation of subatomic and atomic particles. Forms of electromagnetic waves such as light, radio waves and lasers must control deep space engines. We won't get far on our Earth accustomed hydrocarbon fuels.

Shallow Lunar Seismic Activity and the Current Stress State of the Moon

NASA Technical Reports Server (NTRS)

Watters, T. R.; Weber, R. C.; Collins, G. C.; Johnson, C. L.

2017-01-01

A vast, global network of more than 3200 lobate thrust fault scarps has been revealed in high resolution Lunar Reconnaissance Orbiter Camera (LROC) images. The fault scarps very young, less than 50 Ma, based on their small scale and crisp appearance, crosscutting relations with small-diameter impact craters, and rates of infilling of associated small, shallow graben and may be actively forming today. The population of young thrust fault scarps provides a window into the recent stress state of the Moon and offers insight into the origin of global lunar stresses. The distribution of orientations of the fault scarps is non-random, inconsistent with isotropic stresses from late-stage global contraction as the sole source of stress Modeling shows that tidal stresses contribute significantly to the current stress state of the lunar crust. Tidal stresses (orbital recession and diurnal tides) superimposed on stresses from global contraction result in non-isotropic compressional stress and thrust faults consistent with lobate scarp orientations. Stresses due to orbital recession do not change with orbital position, thus it is with the addition of diurnal stresses that peak stresses are reached. At apogee, diurnal and recession stresses are most compressive near the tidal axis, while at perigee they are most compressive 90 degrees away from the tidal axis. Coseismic slip events on currently active thrust faults are expected to be triggered when peak stresses are reached. Analysis of the timing of the 28 the shallow moonquakes recorded by the Apollo seismic network shows that 19 indeed occur when the Moon is closer to apogee, while only 9 shallow events occur when the Moon is closer to perigee. Here we show the results of relocating the shallow moonquake using an algorithm designed for sparse networks to better constrain their epicentral locations in order to compare them with stress models. The model for the current stress state of the Moon is refined by investigating the contribution of polar wander.

Geophysical evidence for melt in the deep lunar interior and implications for lunar evolution

NASA Astrophysics Data System (ADS)

Khan, A.; Connolly, J. A. D.; Pommier, A.; Noir, J.

2014-10-01

Analysis of lunar laser ranging and seismic data has yielded evidence that has been interpreted to indicate a molten zone in the lowermost mantle overlying a fluid core. Such a zone provides strong constraints on models of lunar thermal evolution. Here we determine thermochemical and physical structure of the deep Moon by inverting lunar geophysical data (mean mass and moment of inertia, tidal Love number, and electromagnetic sounding data) in combination with phase-equilibrium computations. Specifically, we assess whether a molten layer is required by the geophysical data. The main conclusion drawn from this study is that a region with high dissipation located deep within the Moon is required to explain the geophysical data. This region is located within the mantle where the solidus is crossed at a depth of ˜1200 km (≥1600°C). Inverted compositions for the partially molten layer (150-200 km thick) are enriched in FeO and TiO2 relative to the surrounding mantle. The melt phase is neutrally buoyant at pressures of ˜4.5-4.6 GPa but contains less TiO2 (<15 wt %) than the Ti-rich (˜16 wt %) melts that produced a set of high-density primitive lunar magmas (density of 3.4 g/cm3). Melt densities computed here range from 3.25 to 3.45 g/cm3 bracketing the density of lunar magmas with moderate-to-high TiO2 contents. Our results are consistent with a model of lunar evolution in which the cumulate pile formed from crystallization of the magma ocean as it overturned, trapping heat-producing elements in the lower mantle.

Response Versus Scan-Angle Corrections for MODIS Reflective Solar Bands Using Deep Convective Clouds

NASA Technical Reports Server (NTRS)

Bhatt, Rajendra; Angal, Amit; Doelling, David R.; Xiong, Xiaoxiong; Wu, Aisheng; Haney, Conor O.; Scarino, Benjamin R.; Gopalan, Arun

2016-01-01

The absolute radiometric calibration of the reflective solar bands (RSBs) of Aqua- and Terra-MODIS is performed using on-board calibrators. A solar diffuser (SD) panel along with a solar diffuser stability monitor (SDSM) system, which tracks the performance of the SD over time, provides the absolute reference for calibrating the MODIS sensors. MODIS also views the moon and deep space through its space view (SV) port for lunar-based calibration and computing the zero input radiance, respectively. The MODIS instrument views the Earths surface through a two-sided scan mirror, whose reflectance is a function of angle of incidence (AOI) and is described by response versus scan-angle (RVS). The RVS for both MODIS instruments was characterized prior to launch. MODIS also views the SD and the moon at two different assigned RVS positions. There is sufficient evidence that the RVS is changing on orbit over time and as a function of wavelength. The SD and lunar observation scans can only track the RVS variation at two RVS positions. Consequently, the MODIS Characterization Support Team (MCST) developed enhanced approaches that supplement the onboard calibrator measurements with responses from pseudo-invariant desert sites. This approach has been implemented in Level 1B (L1B) Collection 6 (C6) for selected short-wavelength bands. This paper presents an alternative approach of characterizing the mirror RVS to derive the time-dependent RVS correction factors for MODIS RSBs using tropical deep convective cloud (DCC) targets. An initial assessment of the DCC response from Aqua-MODIS band 1 C6 data indicates evidence of RVS artifacts, which are not uniform across the scans and are more prevalent in the left side Earth-view scans.

Response Versus Scan-Angle Corrections for MODIS Reflective Solar Bands Using Deep Convective Clouds

NASA Technical Reports Server (NTRS)

Bhatt, Rajendra; Angal, Amit; Doelling, David R.; Xiong, Xiaoxiong; Wu, Aisheng; Haney, Conor O.; Scarino, Benjamin R.; Gopalan, Arun

2016-01-01

The absolute radiometric calibration of the reflective solar bands (RSBs) of Aqua- and Terra-MODIS is performed using on-board calibrators. A solar diffuser (SD) panel along with a solar diffuser stability monitor (SDSM) system, which tracks the performance of the SD over time, provides the absolute reference for calibrating the MODIS sensors. MODIS also views the moon and deep space through its space view (SV) port for lunar-based calibration and computing the zero input radiance, respectively. The MODIS instrument views the Earth's surface through a two-sided scan mirror, whose reflectance is a function of angle of incidence (AOI) and is described by response versus scan-angle (RVS). The RVS for both MODIS instruments was characterized prior to launch. MODIS also views the SD and the moon at two different assigned RVS positions. There is sufficient evidence that the RVS is changing on orbit over time and as a function of wavelength. The SD and lunar observation scans can only track the RVS variation at two RVS positions. Consequently, the MODIS Characterization Support Team (MCST) developed enhanced approaches that supplement the onboard calibrator measurements with responses from pseudo-invariant desert sites. This approach has been implemented in Level 1B (L1B) Collection 6 (C6) for selected short-wavelength bands. This paper presents an alternative approach of characterizing the mirror RVS to derive the time-dependent RVS correction factors for MODIS RSBs using tropical deep convective cloud (DCC) targets. An initial assessment of the DCC response from Aqua-MODIS band 1 C6 data indicates evidence of RVS artifacts, which are not uniform across the scans and are more prevalent in the left side Earth-view scans.

Response versus scan-angle corrections for MODIS reflective solar bands using deep convective clouds

NASA Astrophysics Data System (ADS)

Bhatt, Rajendra; Angal, Amit; Doelling, David R.; Xiong, Xiaoxiong; Wu, Aisheng; Haney, Conor O.; Scarino, Benjamin R.; Gopalan, Arun

2016-05-01

The absolute radiometric calibration of the reflective solar bands (RSBs) of Aqua- and Terra-MODIS is performed using on-board calibrators. A solar diffuser (SD) panel along with a solar diffuser stability monitor (SDSM) system, which tracks the degradation of the SD over time, provides the baseline for calibrating the MODIS sensors. MODIS also views the moon and deep space through its space view (SV) port for lunar-based calibration and computing the background, respectively. The MODIS instrument views the Earth's surface using a two-sided scan mirror, whose reflectance is a function of the angle of incidence (AOI) and is described by response versus scan-angle (RVS). The RVS for both MODIS instruments was characterized prior to launch. MODIS also views the SD and the moon at two different AOIs. There is sufficient evidence that the RVS is changing on orbit over time and as a function of wavelength. The SD and lunar observation scans can only track the RVS variation at two AOIs. Consequently, the MODIS Characterization Support Team (MCST) developed enhanced approaches that supplement the onboard calibrator measurements with responses from the pseudo-invariant desert sites. This approach has been implemented in Level 1B (L1B) Collection 6 (C6) for select short-wavelength bands. This paper presents an alternative approach of characterizing the mirror RVS to derive the time-dependent RVS correction factors for MODIS RSBs using tropical deep convective cloud (DCC) targets. An initial assessment of the DCC response from Aqua-MODIS band 1 C6 data indicates evidence of RVS artifacts, which are not uniform across the scans and are more prevalent at the beginning of the earth-view scan.

NASA Acting Administrator Robert Lightfoot presents the 2018 "St

NASA Image and Video Library

2018-02-12

NASA Acting Administrator Robert Lightfoot delivers the "State of NASA", February 12, 2018, at the Marshall Space Flight Center in Huntsville, Alabama. In his address, Lightfoot discussed what the President's Fiscal Year 2019 budget request means for America's space agency. According to Lightfoot, it "reflects the administration's confidence that America will lead the way back to the Moon and take the next giant leap". Lightfoot delivered the "State of NASA" address in Marshall's Center for Advanced Manufacturing where engineers are pushing boundaries in the fields of additive manufacturing, 3D printing, and more. Hardware for NASA's Space Launch System and a model of the agency's Orion spacecraft served as a backdrop for the annual event. SLS, which is managed by Marshall, will enable a new era of exploration beyond Earth's orbit by launching astronauts on missions to deep-space destinations including the Moon and Mars.

NASA Acting Administrator Robert Lightfoot presents the 2018 "St

NASA Image and Video Library

2018-02-12

Marshall Space Flight Center Director Todd May introduces NASA Acting Adminstrator Robert Lightfoot prior to his delivery of the "State of NASA", February 12, 2018, at the Marshall Space Flight Center in Huntsville, Alabama. In his address, Lightfoot discussed what the President's Fiscal Year 2019 budget request means for America's space agency. According to Lightfoot, it "reflects the administration's confidence that America will lead the way back to the Moon and take the next giant leap". Lightfoot delivered the "State of NASA" address in Marshall's Center for Advanced Manufacturing where engineers are pushing boundaries in the fields of additive manufacturing, 3D printing, and more. Hardware for NASA's Space Launch System and a model of the agency's Orion spacecraft served as a backdrop for the annual event. SLS, which is managed by Marshall, will enable a new era of exploration beyond Earth's orbit by launching astronauts on missions to deep-space destinations including the Moon and Mars.

Integrated Network Architecture for Sustained Human and Robotic Exploration

NASA Technical Reports Server (NTRS)

Noreen, Gary; Cesarone, Robert; Deutsch, Leslie; Edwards, Charles; Soloff, Jason; Ely, Todd; Cook, Brian; Morabito, David; Hemmati, Hamid; Piazolla, Sabino;

Mapping the Concentration of Iron, Titanium, and Thorium in Mare Basalts in the Western Procellarum Region of the Moon

NASA Technical Reports Server (NTRS)

Flor, E. L.; Jolliff, B. L.; Gillis, J. J.

2003-01-01

Mare basalt flows in the Western Procellarum region (WPR) are extensive and include some of the youngest geologic features on the Moon. Compositional remote sensing by the Lunar Prospector gammaray spectrometer (LPGRS) indicates elevated Th concentrations in many of these flows relative to basalts sampled by the Apollo and Luna missions [1,2,3,4]. The primary goals of this investigation are to determine whether the Th enrichment in this region contributed to the extensive and prolonged volcanism in the WPR, and to determine whether the Th is inherent to the basalts themselves or a result of contamination from nonvolcanic material. Thorium enrichment indigenous to the basalts of the Western Procellarum Region would provide evidence that the general concentration of Th in the Procellarum region extends below the crust and possibly as deep as the sources for the basalts themselves.

Volatile elements in and on lunar volcanic glasses: What do they tell us about lunar genesis?

NASA Technical Reports Server (NTRS)

Koeberl, C.

1984-01-01

There are good reasons to believe that lunar volcanic glasses originated from a deep interior source. The presence of a thin layer of surface correlated elements on these glasses may indicate that the Moon has some reservoirs that are enriched in volatiles. Since the glasses themselves do not show similar enrichment, the source should be of limited extent. Three scenarios are advanced for the origin of these elements. The mechanism for lunar volcanism differs from the mechanism for volcanism on Earth since the former produces bubbling and the latter explosive fountaining. From the condensation behavior of the volatile compounds, which leads to heterogeneous condensation, it is concluded that comparing element ratios of surface correlated elements gives little sense. It seems as if the volatile reservoirs are of rather limited extent and that they do not enlarge the volatile content of the bulk Moon significantly.

Results from the Apollo passive seismic experiment

NASA Technical Reports Server (NTRS)

Lathum, G.; Nakamura, Y.; Dorman, J.; Duennebier, F.; Ewing, M.; Lammlein, D.

1974-01-01

Recent results from the Apollo seismic network suggest that primitive differentiation occurred in the outer shell of the moon to a depth of approximately 300 km; and the central region of the moon is presently molten to a radius of between 200 and 300 km. If early melting to a depth of 300 to 400 km was a consequence of accretional energy, very short accretion times are required. The best model for the zone of original differentiation appears to be a crust 40 to 80 km thick, ranging in composition from anorthositic gabbro to gabbro; overlying an ultramafic cumulate (olivine-pyroxene) about 250 km thick. The best candidate for the molten core appears to be iron or iron sulphide. A new class of seismic signals has recently been identified that may correspond to shallow moonquakes. These are rare, but much more energetic than the more numerous, deep moonquakes.

Results from the Apollo passive seismic experiment

NASA Technical Reports Server (NTRS)

Latham, G.; Nakamura, Y.; Dorman, J.; Duennebier, F.; Ewing, M.; Lammlein, D.

1977-01-01

Recent results from the Apollo Seismic Network suggest that primitive differentiation occurred in the outer shell of the moon to a depth of approximately 300 km and the central region of the moon is presently molten to a radius of between 200 and 300 km. If early melting to a depth of 300 to 400 km was a consequence of accretional energy, very short accretion times are required. It was shown that the best model for the zone of original differentiation is a crust 40 to 80 km thick, ranging in composition from anorthositic gabbro to gabbro, and overlying an ultramafic cumulate about 250 km thick. The best candidate for the molten core appears to be iron or iron sulphide. A new class of seismic signals recently were identified that may correspond to shallow moonquakes. These are rare, but much more energetic than the more numerous, deep moonquakes.

2014 Summer Series - Brian Lewis - Skimming the Lunar Surface for Science: The LADEE Mission

NASA Image and Video Library

2014-07-15

On Sept. 6, 2013, a near-perfect launch of the first Minotaur V rocket successfully carried NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) into space. LADEE arrived at the Moon on October 6, 2013, during the government shutdown. With commissioning completed, LADEE lowered periapsis over the sunrise terminator on Nov. 10, and on Nov. 20 lowered apoapsis as well. On April 11, after its primary mission was complete, LADEE performed it's final maneuver, placing it in a very low-altitude orbit that would yield a short period of highly valuable science while guaranteeing impact on the far side of the moon. On April 15, LADEE flew through a four hour lunar eclipse, demonstrating an ability to survive low temperatures and a deep drain on battery systems. LADEE ultimately impacted on the lunar surface between 9:30 pm and 10:22 pm PDT on April 17, 2014.

Global Exploration Roadmap Derived Concept for Human Exploration of the Moon

NASA Technical Reports Server (NTRS)

Whitley, Ryan; Landgraf, Markus; Sato, Naoki; Picard, Martin; Goodliff, Kandyce; Stephenson, Keith; Narita, Shinichiro; Gonthier, Yves; Cowley, Aiden; Hosseini, Shahrzad;

Deep Pyriform Space: Anatomical Clarifications and Clinical Implications.

PubMed

Surek, Christopher K; Vargo, James; Lamb, Jerome

2016-07-01

The purpose of this study was to define the anatomical boundaries, transformation in the aging face, and clinical implications of the Ristow space. The authors propose a title of deep pyriform space for anatomical continuity. The deep pyriform space was dissected in 12 hemifacial fresh cadaver dissections. Specimens were divided into three separate groups. For group 1, dimensions were measured and plaster molds were fashioned to evaluate shape and contour. For group 2, the space was injected percutaneously with dyed hyaluronic acid to examine proximity relationships to adjacent structures. For group 3, the space was pneumatized to evaluate its cephalic extension. The average dimensions of the deep pyriform space are 1.1 × 0.9 cm. It is bounded medially by the depressor septi nasi and cradled laterally and superficially in a "half-moon" shape by the deep medial cheek fat and lip elevators. The angular artery courses on the roof of the space within a septum between the space and deep medial cheek fat. Pneumatization of the space traverses cephalic to the level of the tear trough ligament in a plane deep to the premaxillary space. The deep pyriform space is a midface cavity cradled by the pyriform aperture and deep medial cheek compartment. Bony recession of the maxilla with age predisposes this space for use as a potential area of deep volumization to support overlying cheek fat and draping lip elevators. The position of the angular artery in the roof of the space allows safe injection on the bone without concern for vascular injury.

The orbital TUS detector simulation

NASA Astrophysics Data System (ADS)

Grinyuk, A.; Grebenyuk, V.; Khrenov, B.; Klimov, P.; Lavrova, M.; Panasyuk, M.; Sharakin, S.; Shirokov, A.; Tkachenko, A.; Tkachev, L.; Yashin, I.

2017-04-01

The TUS space experiment is aimed at studying energy and arrival distribution of UHECR at E > 7 × 1019 eV by using the data of EAS fluorescent radiation in atmosphere. The TUS mission was launched at the end of April 2016 on board the dedicated ;Lomonosov; satellite. The TUSSIM software package has been developed to simulate performance of the TUS detector for the Fresnel mirror optical parameters, the light concentrator of the photo detector, the front end and trigger electronics. Trigger efficiency crucially depends on the background level which varies in a wide range: from 0.2 × 106 to 15 × 106 ph/(m2 μ s sr) at moonless and full moon nights respectively. The TUSSIM algorithms are described and the expected TUS statistics is presented for 5 years of data collection from the 500 km solar-synchronized orbit with allowance for the variability of the background light intensity during the space flight.

J-2X powerpack

NASA Image and Video Library

2012-10-05

NASA removed J-2X engine No. 10001 from the A-2 Test Stand at Stennis Space Center in early October. Opening of the test stand clamshell flooring allowed a clear view of the next-generation engine and stub nozzle, which is being built to help power future deep-space missions. The engine is an upgrade from the heritage J-2 rocket engine, which helped power Apollo missions to the moon during the late 1960s and early 1970s.

Rethinking turbidite paleoseismology along the Cascadia subduction zone

USGS Publications Warehouse

Atwater, Brian F.; Carson, Bobb; Griggs, Gary B.; Johnson, H. Paul; Salmi, Marie

2014-01-01

A stratigraphic synthesis of dozens of deep-sea cores, most of them overlooked in recent decades, provides new insights into deep-sea turbidites as guides to earthquake and tsunami hazards along the Cascadia subduction zone, which extends 1100 km along the Pacific coast of North America. The synthesis shows greater variability in Holocene stratigraphy and facies off the Washington coast than was recognized a quarter century ago in a confluence test for seismic triggering of sediment gravity flows. That test compared counts of Holocene turbidites upstream and downstream of a deep-sea channel junction. Similarity in the turbidite counts among seven core sites provided evidence that turbidity currents from different submarine canyons usually reached the junction around the same time, as expected of widespread seismic triggering. The fuller synthesis, however, shows distinct differences between tributaries, and these differences suggest sediment routing for which the confluence test was not designed. The synthesis also bears on recent estimates of Cascadia earthquake magnitudes and recurrence intervals. The magnitude estimates hinge on stratigraphic correlations that discount variability in turbidite facies. The recurrence estimates require turbidites to represent megathrust earthquakes more dependably than they do along a flow path where turbidite frequency appears limited less by seismic shaking than by sediment supply. These concerns underscore the complexity of extracting earthquake history from deep-sea turbidites at Cascadia.

Diverse rupture processes in the 2015 Peru deep earthquake doublet.

PubMed

Ye, Lingling; Lay, Thorne; Kanamori, Hiroo; Zhan, Zhongwen; Duputel, Zacharie

2016-06-01

Earthquakes in deeply subducted oceanic lithosphere can involve either brittle or dissipative ruptures. On 24 November 2015, two deep (606 and 622 km) magnitude 7.5 and 7.6 earthquakes occurred 316 s and 55 km apart. The first event (E1) was a brittle rupture with a sequence of comparable-size subevents extending unilaterally ~50 km southward with a rupture speed of ~4.5 km/s. This earthquake triggered several aftershocks to the north along with the other major event (E2), which had 40% larger seismic moment and the same duration (~20 s), but much smaller rupture area and lower rupture speed than E1, indicating a more dissipative rupture. A minor energy release ~12 s after E1 near the E2 hypocenter, possibly initiated by the S wave from E1, and a clear aftershock ~165 s after E1 also near the E2 hypocenter, suggest that E2 was likely dynamically triggered. Differences in deep earthquake rupture behavior are commonly attributed to variations in thermal state between subduction zones. However, the marked difference in rupture behavior of the nearby Peru doublet events suggests that local variations of stress state and material properties significantly contribute to diverse behavior of deep earthquakes.

Future Concepts for Integrating the Space Launch System and the Multi-Purpose Crew Vehicle into a Reusable Space Transportation Infrastructure

NASA Technical Reports Server (NTRS)

Smitherman, David; Woodcock, Gordon

2012-01-01

A space transportation infrastructure is described that utilizes the Space Launch System (SLS), the Mulit-Purpose Crew Vehicle (MPCV), the International Space Station (ISS), and propellant depot servicing platforms to support all foreseeable missions in the Earth-Moon vicinity and deep space out to Mars. The infrastructure utilizes current expendable launch vehicle (ELV) systems such as the Delta IV Heavy, Atlas V, and Falcon 9, for commercial crew, cargo, and propellant launches to a Low-Earth-Orbit (LEO) Depot and/or the ISS. The SLS provides all payload and propellant launches to the Earth-Moon Langrange Point 1 (EML1) Depot to support new reusable in-space transportation vehicles. The ISS or follow-on LEO Depot supports missions to Geosynchronous Earth Orbit (GEO) for satellite servicing and to Earth-Moon L1 for EML1 Depot missions. The EML1 Depot supports Lunar, Earth-Sun L2 (ESL2), Asteroid, and Mars missions. New vehicle design concepts are presented that can be launched utilizing the SLS and current ELV systems. These new reusable vehicle concepts include a Crew Transfer Vehicle (CTV) derived from the MPCV and a reusable Cryogenic Propulsion Stage (CPS) for crew transportation between the LEO Depot, EML1 Depot and missions beyond the Earth-Moon vicinity; a new reusable Lunar Lander for crew transportation between the EML1 Depot and the lunar surface; and a new reusable Deep Space Habitat (DSH) with a CTV to support crew missions from the EML1 Depot to ESL2, Asteroids, and a Mars Orbital Depot. The LEO Depot, EML1 Depot, and Mars Orbital Depot are based on International Space Station (ISS) heritage hardware. Data provided includes the number of launches required for each mission utilizing SLS and current ELV systems (Delta IV Heavy or equivalent) and the approximate vehicle masses and propellant requirements. Also included is a discussion on affordability with ideas on technologies that could reduce the number of launches required and thoughts on how this infrastructure might be implemented incrementally over the next few decades. The potential benefits of this infrastructure include competitive bidding for ELV flights and propellant services, development of new reusable in-space vehicles, and development of a robust multiuse infrastructure that can support many government and commercial missions simultaneously.

SMART-1 leaves Earth on a long journey to the Moon

NASA Astrophysics Data System (ADS)

2003-09-01

The European Space Agency’s SMART-1 was one of three payloads on Ariane Flight 162. The generic Ariane-5 lifted off from the Guiana Space Centre, Europe’s spaceport at Kourou, French Guiana, at 2014 hrs local time (2314 hrs GMT) on 27 September (01:14 Central European Summer time on 28 September). 42 minutes after launch, SMART-1 as last of the three satellites had been successfully released into a geostationary transfer orbit (654 x 35 885 km, inclined at 7 degrees to the Equator). While the other two satellites are due to manoeuvre towards geostationary orbit, the 367 kg SMART-1 will begin a much longer journey to a target ten times more distant than the geostationary orbit: the Moon. “Europe can be proud”, said ESA Director General Jean-Jacques Dordain, after witnessing the launch from ESA’s ESOC space operations centre in Darmstadt, Germany, “we have set course for the Moon again. And this is only the beginning: we are preparing to reach much further”. The spacecraft has deployed its solar arrays and is currently undergoing initial checkout of its systems under control from ESA/ESOC. This checkout will continue until 4 October and will include with the initial firing of SMART-1’s innovative ion engine. By ion drive to the Moon “Science and technology go hand in hand in this exciting mission to the Moon. The Earth and Moon have over 4 thousand million years of shared history, so knowing the Moon better will help scientists in Europe and all over the world to better understand our planet and will give them valuable new hints on how to better safeguard it” said ESA Director of Science David Southwood, following the launch from Kourou. As the first mission in the new series of Small Missions for Advanced Research in Technology, SMART-1 is mainly designed to demonstrate innovative and key technologies for future deep space science missions. The first technology to be demonstrated on SMART-1 will be Solar Electric Primary Propulsion (SEPP), a highly efficient and lightweight propulsion system that is ideal for long-duration deep space missions in and beyond our solar system. SMART-1’s propulsion system consists in a single ion engine fuelled by 82 kg of xenon gas and pure solar energy. This plasma thruster relies on the “Hall effect” to accelerate xenon ions to speed up to 16,000 m/s (or 57 600 km/hr). It is able to deliver 70 mN of thrust with a specific impulse (the ratio between thrust and propellant consumption) 5 to 10 times better than traditional chemical thrusters and for much longer durations (months or even years, compared to the few minutes’ operating times typical of traditional chemical engines). The ion engine is scheduled to go into action on 30 September. At first, it will fire almost continuously -stopping only when the spacecraft is in the Earth’s shadow - to accelerate the probe (at about 0.2 mm/s2) and raise the altitude of its perigee (the lowest point of its orbit) from 654 to 14 000 km. This manoeuvre will take about 80 days to complete and will place the spacecraft safely above the radiation belts that surround the Earth. Commissioning will be completed within 2 weeks, after which ESA’s control centre at ESOC will be in contact with the spacecraft for two 8-hour periods every week. Once at a safe distance from Earth, SMART-1 will fire its thruster for periods of several days to progressively raise its apogee (the maximum altitude of its orbit) to the orbit of the Moon. At 200 000 km from Earth, it will begin receiving significant tugs from the Moon as it passes by. It will then perform three gravity-assist manoeuvres while flying by the Moon in late December 2004, late January and February 2005. Eventually, SMART-1 will be “captured” and enter a near-polar elliptical lunar orbit in March 2005. SMART-1 will then use its thruster to reduce the altitude and eccentricity of this orbit. During this 18-month transfer phase, the solar-electric primary propulsion’s performance, and its interactions with the spacecraft and its environment, will be closely monitored by the Spacecraft Potential, Electron & Dust Experiment (SPEDE) and the Electric Propulsion Diagnostic Package (EPDP) to detect possible side-effects or interactions with natural electric and magnetic phenomena in nearby space. A promising technology, Solar Electric Primary Propulsion could be applied to numerous interplanetary missions in the Solar System, reducing the size and cost of propulsion systems while increasing manoeuvring flexibility and the mass available for scientific instrumentation. In addition to Solar Electric Primary Propulsion, SMART-1 will demonstrate a wide range of new technologies like a Li-Ion modular battery package; new-generation high-data-rate deep space communications in X and Ka bands with the X/Ka-band Telemetry and Telecommand Experiment (KaTE); a computer technique enabling spacecraft to determine their position autonomously in space, which is the first step towards fully autonomous spacecraft navigation. Digging for the Moon’s remaining secrets In April 2005 SMART-1 will begin the second phase of its mission, due to last at least six months and dedicated to the study of the Moon from a near polar orbit. For more than 40 years, the Moon has been visited by automated space probes and by nine manned expeditions, six of which landed on its surface. Nevertheless, much remains to be learnt about our closest neighbour, and SMART-1’s payload will conduct observations never performed before in such detail. The Advanced/Moon Micro-Imaging Experiment (AMIE) miniaturised CCD camera will provide high-resolution and high-sensitivity imagery of the surface, even in poorly lit polar areas. The highly compact SIR infrared spectrometer will map lunar materials and look for water and carbon dioxide ice in permanently shadowed craters. The Demonstration Compact Imaging X-ray Spectrometer (D-CIXS) will provide the first global chemical map of the Moon and the X-ray Solar Monitor (XSM) will perform spectrometric observations of the Sun and provide calibration data to D-CIXS to compensate for solar variability. The SPEDE experiment used to monitor Solar Electric Primary Propulsion interactions with the environment will also study how the solar wind affects the Moon. The overall data collected by SMART-1 will provide new inputs for studies of the evolution of the Moon, its chemical composition and its geophysical processes, and also for comparative planetology in general. Paving the way for future space probes In addition to valuable lunar science, SMART-1’s payload will be involved in the mission’s technology demonstrations to prepare for future-generation deep space missions. For instance, the AMIE camera will be used to validate the On-Board Autonomous Navigation (OBAN) algorithm, which correlates data from sensors and star trackers to provide navigational data. It will also participate in a laser communication link experiment with ESA’s optical ground station at the Teide Observatory in Tenerife, Canary Islands, trying to detect an incoming laser beam from the ground. Using both AMIE and KaTE hardware, the Radio Science Investigation System (RSIS) experiment will demonstrate a new way of gauging the interiors of planets and their moons by detecting the well-known tilting motion of the Moon. This technology can be used later by ESA planetary missions. SMART-1 was developed for ESA by the Swedish Space Corporation, as prime contractor, with contributions from almost 30 contractors from 11 European countries and the United States. Despite its small size, the spacecraft carries 19 kg of science payload consisting in experiments led by Principal Investigators from Finland, Germany, Italy, Switzerland and the United Kingdom. Despite its relatively small budget and short development schedule, SMART-1 holds tremendous potential for future missions and is a clear illustration of Europe’s ambitions in the exploration of the solar system, also highlighted by June’s launch of Mars Express, which has now completed over the half on its journey to Mars, and the launch of Rosetta, due in February 2004, to visit comet Churyumov-Gerasimenko.

Evolution of the earliest mantle caused by the magmatism-mantle upwelling feedback: Implications for the Moon and the Earth

NASA Astrophysics Data System (ADS)

Ogawa, M.

2017-12-01

The two most important agents that cause mantle evolution are magmatism and mantle convection. My earlier 2D numerical models of a coupled magmatism-mantle convection system show that these two agents strongly couple each other, when the Rayleigh number Ra is sufficiently high: magmatism induced by a mantle upwelling flow boosts the upwelling flow itself. The mantle convection enhanced by this positive feedback (the magmatism-mantle upwelling, or MMU, feedback) causes vigorous magmatism and, at the same time, strongly stirs the mantle. I explored how the MMU feedback influences the evolution of the earliest mantle that contains the magma ocean, based on a numerical model where the mantle is hot and its topmost 1/3 is partially molten at the beginning of the calculation: The evolution drastically changes its style, as Ra exceeds the threshold for onset of the MMU feedback, around 107. At Ra < 107, basaltic materials generated by the initial widespread magmatism accumulate in the deep mantle to form a layer; the basaltic layer is colder than the overlying shallow mantle. At Ra > 107, however, the mantle remains compositionally more homogeneous in spite of the widespread magmatism, and the deep mantle remains hotter than the shallow mantle, because of the strong convective stirring caused by the feedback. The threshold value suggests that the mantle of a planet larger than Mars evolves in a way substantially different from that in the Moon does. Indeed, in my earlier models, magmatism makes the early mantle compositionally stratified in the Moon, but the effects of strong convective stirring overwhelms that of magmatism to keep the mantle compositionally rather homogeneous in Venus and the Earth. The MMU feedback is likely to be a key to understanding why vestiges of the magma ocean are so scarce in the Earth.

Dielectric Breakdown Weathering by Solar Energetic Particles Charging Airless Bodies in the Inner Solar System

NASA Astrophysics Data System (ADS)

Jordan, A.; Stubbs, T. J.; Wilson, J. K.; Schwadron, N.; Spence, H. E.; Hayne, P. O.; Izenberg, N.

2016-12-01

Solar energetic particles (SEPs) can penetrate regoliths of airless bodies to depths of 1 mm and cause deep dielectric charging. This charging is predicted to dissipate slowly (on the order of days) in regoliths with low electrical conductivities, which could form subsurface electric fields (> 106 V/m) large enough to cause dielectric breakdown (or "sparking"). Colder regoliths are expected to have lower conductivities, so the coldest regions of airless planetary bodies can become the most deep dielectrically charged. Consequently, large SEP events may cause dielectric breakdown in these regions, possibly contributing to space weathering on airless bodies in the inner solar system. Previous work has predicted that, in permanently shadowed regions (PSRs) on the Moon, breakdown weathering may have melted and/or vaporized 10-25 wt% of the meteoritically gardened regolith, a percentage comparable to weathering by meteoroid impacts. But much of the Moon's nightside can also reach cold (<100 K) temperatures, so we now show how breakdown weathering may have affected 4-11 wt% of the gardened regolith over the entire lunar surface. We use data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO) to show two examples of SEP events that may have caused breakdown on the Moon. We also scale large SEP events to the orbit of Mars and predict the rate at which they may cause dielectric breakdown on Phobos and Deimos, whose polar regions remain <100 K during their long winters (nearly half an Earth year). On these satellites, the gardening rates are unknown, so we estimate the percentage of regolith affected in these locations as a function of gardening rate. Finally, we briefly show that dielectric breakdown may occur on asteroids that have either high obliquities or PSRs, like Vesta and Ceres, respectively. This work also emphasizes the need for laboratory experiments to inform both remote sensing observations and the analysis of samples already obtained during the Luna and Apollo missions.

Exomoon Habitability Constrained by Illumination and Tidal Heating

PubMed Central

2013-01-01

Abstract The detection of moons orbiting extrasolar planets (“exomoons”) has now become feasible. Once they are discovered in the circumstellar habitable zone, questions about their habitability will emerge. Exomoons are likely to be tidally locked to their planet and hence experience days much shorter than their orbital period around the star and have seasons, all of which works in favor of habitability. These satellites can receive more illumination per area than their host planets, as the planet reflects stellar light and emits thermal photons. On the contrary, eclipses can significantly alter local climates on exomoons by reducing stellar illumination. In addition to radiative heating, tidal heating can be very large on exomoons, possibly even large enough for sterilization. We identify combinations of physical and orbital parameters for which radiative and tidal heating are strong enough to trigger a runaway greenhouse. By analogy with the circumstellar habitable zone, these constraints define a circumplanetary “habitable edge.” We apply our model to hypothetical moons around the recently discovered exoplanet Kepler-22b and the giant planet candidate KOI211.01 and describe, for the first time, the orbits of habitable exomoons. If either planet hosted a satellite at a distance greater than 10 planetary radii, then this could indicate the presence of a habitable moon. Key Words: Astrobiology—Extrasolar planets—Habitability—Habitable zone—Tides. Astrobiology 13, 18–46. PMID:23305357

User's Guide - WRF Lightning Assimilation

EPA Pesticide Factsheets

This document describes how to run WRF with the lightning assimilation technique described in Heath et al. (2016). The assimilation method uses gridded lightning data to trigger and suppress sub-grid deep convection in Kain-Fritsch.

Exercise-Induced Asthma

MedlinePlus

... as triggers include: Cold air Dry air Air pollution High pollen counts Chlorine in swimming pools Chemicals used with ice rink resurfacing equipment Respiratory infections or other lung disease Activities with extended periods of deep breathing, such ...

Breakup of last glacial deep stratification in the South Pacific

NASA Astrophysics Data System (ADS)

Basak, Chandranath; Fröllje, Henning; Lamy, Frank; Gersonde, Rainer; Benz, Verena; Anderson, Robert F.; Molina-Kescher, Mario; Pahnke, Katharina

2018-02-01

Stratification of the deep Southern Ocean during the Last Glacial Maximum is thought to have facilitated carbon storage and subsequent release during the deglaciation as stratification broke down, contributing to atmospheric CO2 rise. Here, we present neodymium isotope evidence from deep to abyssal waters in the South Pacific that confirms stratification of the deepwater column during the Last Glacial Maximum. The results indicate a glacial northward expansion of Ross Sea Bottom Water and a Southern Hemisphere climate trigger for the deglacial breakup of deep stratification. It highlights the important role of abyssal waters in sustaining a deep glacial carbon reservoir and Southern Hemisphere climate change as a prerequisite for the destabilization of the water column and hence the deglacial release of sequestered CO2 through upwelling.

Drivers of deep-water renewal events observed over 13 years in the South Basin of Lake Baikal

NASA Astrophysics Data System (ADS)

Tsimitri, Chrysanthi; Rockel, Burkhardt; Wüest, Alfred; Budnev, Nikolay M.; Sturm, Michael; Schmid, Martin

2015-03-01

Lake Baikal, with a depth of 1637 m, is characterized by deep-water intrusions that bridge the near-surface layer to the hypolimnion. These episodic events transfer heat and oxygen over large vertical scales and maintain the permanent temperature stratified deep-water status of the lake. Here we evaluate a series of intrusion events that reached the bottom of the lake in terms of the stratification and the wind conditions under which they occurred and provide a new insight into the triggering mechanisms. We make use of long-term temperature and current meter data (2000-2013) recorded in the South Basin of the lake combined with wind data produced with a regional downscaling of the global NCEP-RA1 reanalysis product. A total of 13 events were observed during which near-surface cold water reached the bottom of the South Basin at 1350 m depth. We found that the triggering mechanism of the events is related to the time of the year that they take place. We categorized the events in three groups: (1) winter events, observed shortly before the complete ice cover of the lake that are triggered by Ekman coastal downwelling, (2) under-ice events, and (3) spring events, that show no correlation to the wind conditions and are possibly connected to the increased spring outflow of the Selenga River. This article was corrected on 18 MAR 2015. See the end of the full text for details.

Evaluation of deep moonquake source parameters: Implication for fault characteristics and thermal state

NASA Astrophysics Data System (ADS)

Kawamura, Taichi; Lognonné, Philippe; Nishikawa, Yasuhiro; Tanaka, Satoshi

2017-07-01

While deep moonquakes are seismic events commonly observed on the Moon, their source mechanism is still unexplained. The two main issues are poorly constrained source parameters and incompatibilities between the thermal profiles suggested by many studies and the apparent need for brittle properties at these depths. In this study, we reinvestigated the deep moonquake data to reestimate its source parameters and uncover the characteristics of deep moonquake faults that differ from those on Earth. We first improve the estimation of source parameters through spectral analysis using "new" broadband seismic records made by combining those of the Apollo long- and short-period seismometers. We use the broader frequency band of the combined spectra to estimate corner frequencies and DC values of spectra, which are important parameters to constrain the source parameters. We further use the spectral features to estimate seismic moments and stress drops for more than 100 deep moonquake events from three different source regions. This study revealed that deep moonquake faults are extremely smooth compared to terrestrial faults. Second, we reevaluate the brittle-ductile transition temperature that is consistent with the obtained source parameters. We show that the source parameters imply that the tidal stress is the main source of the stress glut causing deep moonquakes and the large strain rate from tides makes the brittle-ductile transition temperature higher. Higher transition temperatures open a new possibility to construct a thermal model that is consistent with deep moonquake occurrence and pressure condition and thereby improve our understandings of the deep moonquake source mechanism.

The full moon as a synchronizer of circa-monthly biological rhythms: Chronobiologic perspectives based on multidisciplinary naturalistic research.

PubMed

Reinberg, Alain; Smolensky, Michael H; Touitou, Yvan

Biological rhythmicity is presumed to be an advantageous genetic adaptation of fitness and survival value resulting from evolution of life forms in an environment that varies predictably-in-time during the 24 h, month, and year. The 24 h light/dark cycle is the prime synchronizer of circadian periodicities, and its modulation over the course of the year, in terms of daytime photoperiod length, is a prime synchronizer of circannual periodicities. Circadian and circannual rhythms have been the major research focus of most scientists. Circa-monthly rhythms triggered or synchronized by the 29.5 day lunar cycle of nighttime light intensity, or specifically the light of the full moon, although explored in waterborne and certain other species, have received far less study, perhaps because of associations with ancient mythology and/or an attitude naturalistic studies are of lesser merit than ones that entail molecular mechanisms. In this editorial, we cite our recent discovery through multidisciplinary naturalistic investigation of a highly integrated circadian, circa-monthly, and circannual time structure, synchronized by the natural ambient nyctohemeral, lunar, and annual light cycles, of the Peruvian apple cactus (C. peruvianus) flowering and reproductive processes that occur in close temporal coordination with like rhythms of the honey bee as its pollinator. This finding led us to explore the preservation of this integrated biological time structure, synchronized and/or triggered by environmental light cues and cycles, in the reproduction of other species, including Homo sapiens, and how the artificial light environment of today in which humans reside may be negatively affecting human reproduction efficiency.

Results of the Compensated Earth-Moon-Earth Retroreflector Laser Link (CEMERLL) Experiment

NASA Technical Reports Server (NTRS)

Wilson, K. E.; Leatherman, P. R.; Cleis, R.; Spinhirne, J.; Fugate, R. Q.

1997-01-01

Adaptive optics techniques can be used to realize a robust low bit-error-rate link by mitigating the atmosphere-induced signal fades in optical communications links between ground-based transmitters and deep-space probes. Phase I of the Compensated Earth-Moon-Earth Retroreflector Laser Link (CEMERLL) experiment demonstrated the first propagation of an atmosphere-compensated laser beam to the lunar retroreflectors. A 1.06-micron Nd:YAG laser beam was propagated through the full aperture of the 1.5-m telescope at the Starfire Optical Range (SOR), Kirtland Air Force Base, New Mexico, to the Apollo 15 retroreflector array at Hadley Rille. Laser guide-star adaptive optics were used to compensate turbulence-induced aberrations across the transmitter's 1.5-m aperture. A 3.5-m telescope, also located at the SOR, was used as a receiver for detecting the return signals. JPL-supplied Chebyshev polynomials of the retroreflector locations were used to develop tracking algorithms for the telescopes. At times we observed in excess of 100 photons returned from a single pulse when the outgoing beam from the 1.5-m telescope was corrected by the adaptive optics system. No returns were detected when the outgoing beam was uncompensated. The experiment was conducted from March through September 1994, during the first or last quarter of the Moon.

Possible seasonality in large deep-focus earthquakes

NASA Astrophysics Data System (ADS)

Zhan, Zhongwen; Shearer, Peter M.

2015-09-01

Large deep-focus earthquakes (magnitude > 7.0, depth > 500 km) have exhibited strong seasonality in their occurrence times since the beginning of global earthquake catalogs. Of 60 such events from 1900 to the present, 42 have occurred in the middle half of each year. The seasonality appears strongest in the northwest Pacific subduction zones and weakest in the Tonga region. Taken at face value, the surplus of northern hemisphere summer events is statistically significant, but due to the ex post facto hypothesis testing, the absence of seasonality in smaller deep earthquakes, and the lack of a known physical triggering mechanism, we cannot rule out that the observed seasonality is just random chance. However, we can make a testable prediction of seasonality in future large deep-focus earthquakes, which, given likely earthquake occurrence rates, should be verified or falsified within a few decades. If confirmed, deep earthquake seasonality would challenge our current understanding of deep earthquakes.

SMART-1 technology, scientific results and heritage for future space missions

NASA Astrophysics Data System (ADS)

Foing, B. H.; Racca, G.; Marini, A.; Koschny, D.; Frew, D.; Grieger, B.; Camino-Ramos, O.; Josset, J. L.; Grande, M.; Smart-1 Science; Technology Working Team

2018-02-01

ESA's SMART-1 mission to the Moon achieved record firsts such as: 1) first Small Mission for Advanced Research and Technology; with spacecraft built and integrated in 2.5 years and launched 3.5 years after mission approval; 2) first mission leaving the Earth orbit using solar power alone; 3) most fuel effective mission (60 L of Xenon) and longest travel (13 months) to the Moon!; 4) first ESA mission reaching the Moon and first European views of lunar poles; 5) first European demonstration of a wide range of new technologies: Li-Ion modular battery, deep-space communications in X- and Ka-bands, and autonomous positioning for navigation; 6) first lunar demonstration of an infrared spectrometer and of a Swept Charge Detector Lunar X-ray fluorescence spectrometer; 7) first ESA mission with opportunity for lunar science, elemental geochemistry, surface mineralogy mapping, surface geology and precursor studies for exploration; 8) first controlled impact landing on the Moon with real time observations campaign; 9) first mission supporting goals of the International Lunar Exploration Working Group (ILEWG) in technical and scientific exchange, international collaboration, public and youth engagement; 10) first mission preparing the ground for ESA collaboration in Chandrayaan-1, Chang' E1 and future international lunar exploration. We review SMART-1 highlights and new results that are relevant to the preparation for future lunar exploration. The technology and methods had impact on space research and applications. Recent SMART-1 results are relevant to topics on: 1) the study of properties of the lunar dust, 2) impact craters and ejecta, 3) the study of illumination, 4) radio observations and science from the Moon, 5) support to future missions, 6) identifying and characterising sites for exploration and exploitation. On these respective topics, we discuss recent SMART-1 results and challenges. We also discuss the use of SMART-1 publications library. The SMART-1 archive observations have been used to support the goals of ILEWG. SMART-1 has been useful to prepare for Kaguya, Chandrayaan-1, Chang'E 1, the US Lunar Reconnaissance Orbiter, the LCROSS impact, future lunar landers and upcoming missions, and to contribute towards objectives of the Moon Village and future exploration.

Compact, Deep-Penetrating Geothermal Heat Flow Instrumentation for Lunar Landers

NASA Technical Reports Server (NTRS)

Nagihara, S.; Zacny, K.; Hedlund, M.; Taylor, P. T.

2012-01-01

Geothermal heat flow is obtained as a product of the two separate measurements of geothermal gradient in, and thermal conductivity of, the vertical soi/rock/regolith interval penetrated by the instrument. Heat flow measurements are a high priority for the geophysical network missions to the Moon recommended by the latest Decadal Survey [I] and previously the International Lunar Network [2]. The two lunar-landing missions planned later this decade by JAXA [3] and ESA [4] also consider geothermal measurements a priority.

The morphology and origin of Hadley Rille, the moon

NASA Technical Reports Server (NTRS)

Brewer, T.

1976-01-01

Hadley Rille is directly related to the emplacement of mare basalts in Palus Putredinis. Existing hypotheses of sinuous rille origin are in discord with the cooling behavior of deep lava flows and the strength of materials. It is proposed that Hadley Rille is a channel which returned lava to the southern vent from which it initially extruded and that the channel persisted through many episodes of volcanism. This view is supported by available topographic information obtained by the lunar orbiter photography and the Apollo 15 mission.

Deep Interior: Probing the Structure of Primitive Bodies

NASA Astrophysics Data System (ADS)

Asphaug, Erik; Scheeres, Daniel; Safaeinili, Ali

Deep Interior is a mature Discovery-class mission concept focused on probing the geophysical behavior of primitive bodies, from the mechanics of their exterior materials to the structures of their interiors. Its theme is to discover how small bodies work - to learn the natural origin and evolution of asteroids, comets and other primitive bodies through radar reflection tomography and through detailed observations of the local and global effects of cratering. Learning the structure and mechanical response of asteroids and comets is also a precursor to resource utilization and hazardous asteroid mitigation. Overall the mission is aligned with NASA strategic sub-goal 3C, to advance scientific knowledge of the origin and history of the solar system ... and the hazards and resources present as humans explore space. Deep Interior deploys no complex landers or sub-spacecraft; the scientific instruments are a radar and a camera. A blast cratering experiments triggered by grenades leads to a low cost seismological investigation which complements the radar investigation. A desired addition is an imaging spectrometer. The science instruments are high heritage, as are the navigation techniques for orbiting and station-keeping. The mission conducts the following investigations at one or more asteroids: Radar Reflection Tomography (RRT). The first science phase is to operate a penetrating radar during each several-month rendezvous, deployed in reflection mode in the manner of ongoing radar investigations underway by Mars Express, Mars Reconnaissance Orbiter, and Kaguya. The RRT technique (Safaeinili et al., MAPS 2002) is analogous to performing a "CAT scan" from orbit: closely sampled radar echoes are processed to yield volumetric maps of mechanical and compositional boundaries, and to measure interior dielectric properties. Deep Interior utilizes a polar orbit (or station keeping) while the asteroid spins underneath; the result is to "peel the apple" with thousands of unique radar returns, providing global interior coverage. Camera images allow for the accurate reconstruction of spacecraft position at each radar acquisition. Radar flight heritage has been demonstrated by the MARSIS radar on Mars Express (Picardi et al., Science 2005; Plaut et al., Science 2007), the SHARAD radar onboard the Mars Reconnaissance Orbiter (Seu et al., JGR 2007), and the LRS radar onboard Kaguya (Ono et al, EPS 2007). The Mars radars have discovered detailed subsurface structure to km depths in a variety of terrains; early results from Kaguya demonstrate its ability to detect structure to km depths in basaltic materials on the Moon. A reflection radar deployed in orbit about a primitive body will enjoy significant simplifying benefits compared to using the same instrument for Mars or lunar radar science: (1) The proximity of operations leads to a much higher signal to noise, +30 dB or more. (2) The lack of an ionosphere makes for far simpler data modeling and analysis, compared with what is being required at Mars. (3) The body is globally illuminated during every data acquisition and since the final processing is a fully coherent focused processing based on all available observations, it will remove any "clutter" ambiguities. Laboratory measurements of dielectric properties for a suite of meteorite materials (Heggy et al., LPSC 2007) show that a 10 MHz radar can penetrate a chondritic asteroid up to 5 km diameter, and a 100 MHz radar can penetrate a chondritic asteroid up to 1 km diameter. The dielectric properties of different meteorite types can be discriminated, allowing radar to be used for interior compositional analysis. The primary trade is higher definition navigation for higher-resolution imaging, presuming that penetration requirements are met. It appears reliable that a SHARAD-type radar can image the global interior of a chondritic asteroid up to several km diameter. Radar imaging might leave a number of key questions unanswered, and to directly probe the mechanical behavior of an asteroid we conclude each rendezvous by observing one or more explosion cratering experiments. Cratering (CRT). Cratering is the primary mode of geologic evolution of asteroids, and meteoroid impacts can trigger outbursts on cometary nuclei. The process is important to study for its own sake, and a cratering experiment offers three additional science benefits: (1) final crater diameter and morphology indicates the mechanical behavior of regolith and other exterior materials; (2) cratering exposes the subsurface for analysis of interior materials; and (3) cratering might trigger global reverberations that can be detected using before-and-after image comparisons of toppled boulders and landslides. Small cratering events may be of global consequence on small asteroids (Asphaug, MAPS, in press) and thus a grenade of only a few kg is likely to send a detectable resurfacing reverberation spanning the asteroid. This experiment thus serves as a low cost proxy for primitive body seismology. Global seismic response is quantified using techniques that have been developed on Earth based on estimates for the dynamical acceleration of preciariously balanced rocks (Brune et al., JGR 2003). Ideally the mission would have two cratering charges per rendezvous target, differing by ˜2 orders of magnitude in yield, to bracket local to global response. Cratering and landslide physics will also be studied in this novel microgravity setting, for the purpose of establishing scaling rules and addressing fundamental problems of dense granular flow. Moreover, many cubic meters of ejected regolith are exposed for analysis of size distribution, clast shape, spectral heterogeneity, and dynamics. In the case that the asteroid is metastable (e.g. a rapid rotator), the small cratering event might trigger a global avalanche, in which case Deep Interior will observe the formation of transitory debris disks or small moons (e.g. Scheeres et al., Science 2007). Hazards to the spacecraft from these blast events have been computed from scaling laws for crater ejecta mass-velocity distributions, and are found to be minimal when the spacecraft is a few km away. This hazard drops to zero if the spacecraft is below the horizon of the blast, because dust is cleared out by the solar wind in about a day. Long term debris (moonlets and rings) are easily avoided since stable orbits are dynamically constrained (Scheeres et al., Icarus 1996). Unforeseen impacts with orbiting debris would occur at only a few cm/s.

Blue moon neurovirology: the merits of studying rare CNS diseases of viral origin.

PubMed

O'Donnell, Lauren A; Rall, Glenn F

2010-09-01

While measles virus (MV) continues to have a significant impact on human health, causing 150,000-200,000 deaths worldwide each year, the number of fatalities that can be attributed to MV-triggered central nervous system (CNS) diseases are on the order of a few hundred individuals annually (World Health Organization 2009). Despite this modest impact, substantial effort has been expended to understand the basis of measles-triggered neuropathogenesis. What can be gained by studying such a rare condition? Simply stated, the wealth of studies in this field have revealed core principles that are relevant to multiple neurotropic pathogens, and that inform the broader field of viral pathogenesis. In recent years, the emergence of powerful in vitro systems, novel animal models, and reverse genetics has enabled insights into the basis of MV persistence, the complexity of MV interactions with neurons and the immune system, and the role of immune and CNS development in virus-triggered disease. In this review, we highlight some key advances, link relevant measles-based studies to the broader disciplines of neurovirology and viral pathogenesis, and propose future areas of study for the field of measles-mediated neurological disease.

EKG-based detection of deep brain stimulation in fMRI studies.

PubMed

Fiveland, Eric; Madhavan, Radhika; Prusik, Julia; Linton, Renee; Dimarzio, Marisa; Ashe, Jeffrey; Pilitsis, Julie; Hancu, Ileana

2018-04-01

To assess the impact of synchronization errors between the assumed functional MRI paradigm timing and the deep brain stimulation (DBS) on/off cycling using a custom electrocardiogram-based triggering system METHODS: A detector for measuring and predicting the on/off state of cycling deep brain stimulation was developed and tested in six patients in office visits. Three-electrode electrocardiogram measurements, amplified by a commercial bio-amplifier, were used as input for a custom electronics box (e-box). The e-box transformed the deep brain stimulation waveforms into transistor-transistor logic pulses, recorded their timing, and propagated it in time. The e-box was used to trigger task-based deep brain stimulation functional MRI scans in 5 additional subjects; the impact of timing accuracy on t-test values was investigated in a simulation study using the functional MRI data. Following locking to each patient's individual waveform, the e-box was shown to predict stimulation onset with an average absolute error of 112 ± 148 ms, 30 min after disconnecting from the patients. The subsecond accuracy of the e-box in predicting timing onset is more than adequate for our slow varying, 30-/30-s on/off stimulation paradigm. Conversely, the experimental deep brain stimulation onset prediction accuracy in the absence of the e-box, which could be off by as much as 4 to 6 s, could significantly decrease activation strength. Using this detector, stimulation can be accurately synchronized to functional MRI acquisitions, without adding any additional hardware in the MRI environment. Magn Reson Med 79:2432-2439, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

NASA's First Laser Communication System

NASA Image and Video Library

2017-12-08

A new NASA-developed, laser-based space communication system will enable higher rates of satellite communications similar in capability to high-speed fiber optic networks on Earth. The space terminal for the Lunar Laser Communication Demonstration (LLCD), NASA's first high-data-rate laser communication system, was recently integrated onto the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft. LLCD will demonstrate laser communications from lunar orbit to Earth at six times the rate of the best modern-day advanced radio communication systems. Credit: NASA ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Exploration of the Moon with Remote Sensing, Ground-Penetrating Radar, and the Regolith-Evolved Gas Analyzer (REGA)

NASA Technical Reports Server (NTRS)

Cooper, B. L.; Hoffman, J. H.; Allen, Carlton C.; McKay, David S.

1998-01-01

There are two important reasons to explore the Moon. First, we would like to know more about the Moon itself: its history, its geology, its chemistry, and its diversity. Second, we would like to apply this knowledge to a useful purpose. namely finding and using lunar resources. As a result of the recent Clementine and Lunar Prospector missions, we now have global data on the regional surface mineralogy of the Moon, and we have good reason to believe that water exists in the lunar polar regions. However, there is still very little information about the subsurface. If we wish to go to the lunar polar regions to extract water, or if we wish to go anywhere else on the Moon and extract (or learn) anything at all, we need information in three dimensions an understanding of what lies below the surface, both shallow and deep. The terrestrial mining industry provides an example of the logical steps that lead to an understanding of where resources are located and their economic significance. Surface maps are examined to determine likely locations for detailed study. Geochemical soil sample surveys, using broad or narrow grid patterns, are then used to gather additional data. Next, a detailed surface map is developed for a selected area, along with an interpretation of the subsurface structure that would give rise to the observed features. After that, further sampling and geophysical exploration are used to validate and refine the original interpretation, as well as to make further exploration/ mining decisions. Integrating remotely sensed, geophysical, and sample datasets gives the maximum likelihood of a correct interpretation of the subsurface geology and surface morphology. Apollo-era geophysical and automated sampling experiments sought to look beyond the upper few microns of the lunar surface. These experiments, including ground-penetrating radar and spectrometry, proved the usefulness of these methods for determining the best sites for lunar bases and lunar mining operations.

The Trigger and Data Acquisition System for the 8 tower subsystem of the KM3NeT detector

NASA Astrophysics Data System (ADS)

Manzali, M.; Chiarusi, T.; Favaro, M.; Giacomini, F.; Margiotta, A.; Pellegrino, C.

2016-07-01

KM3NeT is a deep-sea research infrastructure being constructed in the Mediterranean Sea. It will host a large Cherenkov neutrino telescope that will collect photons emitted along the path of the charged particles produced in neutrino interactions in the vicinity of the detector. The philosophy of the DAQ system of the detector foresees that all data are sent to shore after a proper sampling of the photomultiplier signals. No off-shore hardware trigger is implemented and a software selection of the data is performed with an on-line Trigger and Data Acquisition System (TriDAS) to reduce the large throughput due to the environmental light background. A first version of the TriDAS has been developed to operate a prototype detection unit deployed in March 2013 in the abyssal site of Capo Passero (Sicily, Italy), about 3500 m deep. A revised and improved version has been developed to meet the requirements of the final detector, using new tools and modern design solutions. First installation and scalability tests have been performed at the Bologna Common Infrastructure and results comparable to what expected have been observed.

A Novel Animal Model for Investigating the Neural Basis of Focal Dystonia

DTIC Science & Technology

2017-09-01

as the predisposing condition and dry eye as an environmental trigger to model blepharospasm in rodents. This reporting year we demonstrated that 7...benign essential blepharospasm, dry eye , motor plasticity, basal ganglia, deep brain stimulation, eyelids, blinking 16. SECURITY CLASSIFICATION OF: 17...basal ganglia create the predisposing condition and that  eye   irritation from  dry   eye   is the envi‐ ronmental trigger.  Our demonstration that

NASA's Space Launch System: Deep-Space Deployment for SmallSats

NASA Technical Reports Server (NTRS)

Schorr, Andy

2017-01-01

From its upcoming first flight, NASA's new Space Launch System (SLS) will represent a game-changing opportunity for smallsats. On that launch, which will propel the Orion crew vehicle around the moon, the new exploration-class launch vehicle will deploy 13 6U CubeSats into deep-space, where they will continue to a variety of destinations to perform diverse research and demonstrations. Following that first flight, SLS will undergo the first of a series of performance upgrades, increasing its payload capability to low Earth orbit from 70 to 105 metric tons via the addition of a powerful upper stage. With that change to the vehicle's architecture, so too will its secondary payload accommodation for smallsats evolve, with current plans calling for a change from the first-flight limit of 6U to accommodating a range of sizes up to 27U and potentially ESPA-class payloads. This presentation will provide an overview and update on the first launch of SLS and the secondary payloads it will deploy. Currently, flight hardware has been produced for every element of the vehicle, testing of the vehicle's propulsion elements has been ongoing for years, and structural testing of its stages has begun. Major assembly and testing of the Orion Stage Adapter, including the secondary payload accommodations, will be completed this year, and the structure will then be shipped to Kennedy Space Center for integration of the payloads. Progress is being made on those CubeSats, which will include studies of asteroids, Earth, the sun, the moon, and the impacts of radiation on organisms in deep space. They will feature revolutionary innovations for smallsats, including demonstrations of use of a solar sail as propulsion for a rendezvous with an asteroid, and the landing of a CubeSat on the lunar surface. The presentation will also provide an update on progress of the SLS Block 1B configuration that will be used on the rocket's second flight, a discussion of planned secondary payload accommodations on that configuration of the vehicle, and a look at the current state of planning of upcoming missions and what that could mean for deep-space smallsat flight opportunities.

Stochastic does not equal ad hoc. [theories of lunar origin

NASA Technical Reports Server (NTRS)

Hartmann, W. K.

1984-01-01

Some classes of influential events in solar system history are class-predictable but not event-predictable. Theories of lunar origin should not ignore class-predictable stochastic events. Impacts and close encounters with large objects during planet formation are class-predictable. These stochastic events, such as large impacts that triggered ejection of Earth-mantle material into a circum-Earth cloud, should not be rejected as ad hoc. A way to deal with such events scientifically is to investigate their consequences; if it can be shown that they might produce the Moon, they become viable concepts in theories of lunar origin.

Rise of planetary bodies.

NASA Astrophysics Data System (ADS)

Czechowski, Z.; Leliwa-Kopystyński, J.; Teisseyre, R.

Contents: 1. On the probability of the formation of planetary systems. 2. Condensation triggered by supernova explosion and tidal capture theory. 3. Foundations of accretion theory. 4. The structure and evolution of the protoplanetary disk. 5. Coagulation of orbiting bodies. 6. Collision phenomena related to planetology: accretion, fragmentation, cratering. 7. Dynamics of planetesimals: Introduction, Safronov's approach, elements of the kinetic theory of gases, Nakagawa's approach, approaches considering inelastic collisions and gravitational encounters of planetesimals, Hämeen-Anttila approach, planetesimals with different masses. 8. Growth of the planetary embryo: Basic equations, model of growth of planetary embryos. 9. Origin of the Moon and the satellites.

Meltwater routing and the Younger Dryas.

PubMed

Condron, Alan; Winsor, Peter

2012-12-04

The Younger Dryas--the last major cold episode on Earth--is generally considered to have been triggered by a meltwater flood into the North Atlantic. The prevailing hypothesis, proposed by Broecker et al. [1989 Nature 341:318-321] more than two decades ago, suggests that an abrupt rerouting of Lake Agassiz overflow through the Great Lakes and St. Lawrence Valley inhibited deep water formation in the subpolar North Atlantic and weakened the strength of the Atlantic Meridional Overturning Circulation (AMOC). More recently, Tarasov and Peltier [2005 Nature 435:662-665] showed that meltwater could have discharged into the Arctic Ocean via the Mackenzie Valley ~4,000 km northwest of the St. Lawrence outlet. Here we use a sophisticated, high-resolution, ocean sea-ice model to study the delivery of meltwater from the two drainage outlets to the deep water formation regions in the North Atlantic. Unlike the hypothesis of Broecker et al., freshwater from the St. Lawrence Valley advects into the subtropical gyre ~3,000 km south of the North Atlantic deep water formation regions and weakens the AMOC by <15%. In contrast, narrow coastal boundary currents efficiently deliver meltwater from the Mackenzie Valley to the deep water formation regions of the subpolar North Atlantic and weaken the AMOC by >30%. We conclude that meltwater discharge from the Arctic, rather than the St. Lawrence Valley, was more likely to have triggered the Younger Dryas cooling.

Versatile Polymer Nanoparticles as Two-Photon-Triggered Photosensitizers for Simultaneous Cellular, Deep-Tissue Imaging, and Photodynamic Therapy.

PubMed

Guo, Liang; Ge, Jiechao; Liu, Qian; Jia, Qingyan; Zhang, Hongyan; Liu, Weimin; Niu, Guangle; Liu, Sha; Gong, Jianru; Hackbarth, Steffen; Wang, Pengfei

2017-06-01

Clinical applications of current photodynamic therapy (PDT) photosensitizers (PSs) are often limited by their absorption in the UV-vis range that possesses limited tissue penetration ability, leading to ineffective therapeutic response for deep-seated tumors. Alternatively, two-photon excited PS (TPE-PS) using NIR light triggered is one the most promising candidates for PDT improvement. Herein, multimodal polymer nanoparticles (PNPs) from polythiophene derivative as two-photon fluorescence imaging as well as two-photon-excited PDT agent are developed. The prepared PNPs exhibit excellent water dispersibility, high photostability and pH stability, strong fluorescence brightness, and low dark toxicity. More importantly, the PNPs also possess other outstanding features including: (1) the high 1 O 2 quantum yield; (2) the strong two-photon-induced fluorescence and efficient 1 O 2 generation; (3) the specific accumulation in lysosomes of HeLa cells; and (4) the imaging detection depth up to 2100 µm in the mock tissue under two-photon. The multifunctional PNPs are promising candidates as TPE-PDT agent for simultaneous cellular, deep-tissue imaging, and highly efficient in vivo PDT of cancer. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rainfall influence on styles of mass movement

NASA Astrophysics Data System (ADS)

Anderson, S. P.; Rengers, F. K.; Foster, M. A.; Winchell, E. W.; Anderson, R. S.

2017-12-01

Precipitation characteristics influence whether hillslope materials move in rain-splash driven hops, shallow landslides, or in deep-seated failures. While one might expect a particular style of slope failure to dominate in a region, we report on multiple distinctive mass movements on a single ridge, each associated with different weather events. This suggests that understanding climate regulation of denudation rates and hillslope morphology requires quantifying both triggering hydro-climates, and the corresponding hillslope response to the full spectrum of events. We explore these connections on Dakota Ridge, a hogback at the eastern margin of the Colorado Front Range. The dipslope of Dakota Ridge has generated slumps, debris flows, and an earthflow over the last 4 years; Pleistocene-era deep-seated landslides are also evident. We document mass-movements along a 1 km long segment of Dakota Ridge. Weeklong precipitation and flooding in September 2013 produced slumps, each of which displaced 50-100 m3 of mobile regolith several meters downslope, and some of which triggered shallow, relatively non-erosive debris flows. By contrast, a similar precipitation total over the month of May 2015 mobilized an earthflow. The 10 m wide earthflow displaced mobile regolith downslope as much as 10 m over its 150 m length. These recent landslides are dwarfed by a 400 m wide deep-seated landslide that controls slope morphology from ridge crest to toe. Exposure ages (10Be) suggest a late-Pleistocene age for this feature. Although the September 2013 storm produced record-setting rainfall totals at daily, monthly and annual timescales (e.g., annual exceedance probability of <1/1000 for daily totals), the failures from that event, while numerous, were the smallest of all the landslides in the study area. These observations raise the question: what hydro-climatic conditions produce deep-seated, bedrock involved slope failures? Recent storms suggest that within mobile regolith, individual failure size increases with duration of the triggering weather event. Ridge-scale bedrock-involved failures presumably reflect a more persistently wet climate.

Artificial Water Reservoir Triggered Earthquakes at Koyna, India: Completion of the 3 km deep Pilot Borehole

NASA Astrophysics Data System (ADS)

Gupta, H. K.; Tiwari, V. M.; Satyanarayana, H.; Roy, S.; Arora, K.; Patro, P. K.; Shashidhar, D.; Mallika, K.; Akkiraju, V.; Misra, S.; Goswami, D.; Podugu, N.; Mishra, S.

2017-12-01

Koyna, near the west coast of India is the most prominent site of artificial water reservoir triggered seismicity (RTS). Soon after the impoundment of the Koyna Dam in 1962, RTS was observed. It has continued till now. It includes the largest RTS earthquake M 6.3 on December 10, 1967; 22 M≥5.0, and thousands of smaller earthquakes. The entire earthquake activity is limited to an area of about 30 km x 20 km, with most focal depths being within 6 km. There is no other earthquake source within 50 km of the Koyna Dam. An ICDP Workshop held in March 2011 found Koyna to be the most suitable site to investigate reservoir- triggered seismicity (RTS) through deep drilling. Studies carried out in the preparatory phase since 2011 include airborne magnetic and gravity-gradient surveys, MT surveys, drilling of 9 boreholes going to depths of 1500 m and logging, heat flow measurements, seismological investigations including the deployment of six borehole seismometers, and LiDAR. The Second ICDP Workshop held during 16- 18 May 2014, reviewed the progress made and detailed planning of putting the borehole observatory was discussed. The site of a 3 km deep pilot borehole was debated and among the 5 possible location. Based on the seismic activity and logistics the location of the first Pilot Borehole has been finalized and the drilling started on the 21st December 2016. The 3000 m deep borehole was completed on 11th June 2017. The basement was touched at 1247 m depth and there were no sediments below basalt. Several zones with immense fluid losses were encountered. Geophysical Logging has been completed. Cores were recovered from 1269, 1892 and 2091 depths. The cores are 9 m long and with 4 inches diameter. The core recovery is almost 100%. In-situ stress measurements have been conducted at depths of 1600 m onwards.

Investigations related to scientific deep drilling to study reservoir-triggered earthquakes at Koyna, India

NASA Astrophysics Data System (ADS)

Gupta, Harsh; Purnachandra Rao, N.; Roy, Sukanta; Arora, Kusumita; Tiwari, V. M.; Patro, Prasanta K.; Satyanarayana, H. V. S.; Shashidhar, D.; Mallika, K.; Akkiraju, Vyasulu V.; Goswami, Deepjyoti; Vyas, Digant; Ravi, G.; Srinivas, K. N. S. S. S.; Srihari, M.; Mishra, S.; Dubey, C. P.; Raju, D. Ch. V.; Borah, Ujjal; Chinna Reddy, K.; Babu, Narendra; Rohilla, Sunil; Dhar, Upasana; Sen, Mrinal; Bhaskar Rao, Y. J.; Bansal, B. K.; Nayak, Shailesh

2015-09-01

Artificial water reservoir-triggered earthquakes have continued at Koyna in the Deccan Traps province, India, since the impoundment of the Shivaji Sagar reservoir in 1962. Existing models, to comprehend the genesis of triggered earthquakes, suffer from lack of observations in the near field. To investigate further, scientific deep drilling and setting up a fault zone observatory at depth of 5-7 km is planned in the Koyna area. Prior to undertaking deep drilling, an exploratory phase of investigations has been launched to constrain subsurface geology, structure and heat flow regime in the area that provide critical inputs for the design of the deep borehole observatory. Two core boreholes drilled to depths of 1,522 and 1,196 m have penetrated the Deccan Traps and sampled the granitic basement in the region for the first time. Studies on cores provide new and direct information regarding the thickness of the Deccan Traps, the absence of infra-Trappean sediments and the nature of the underlying basement rocks. Temperatures estimated at a depth of 6 km in the area, made on the basis of heat flow and thermal properties data sets, do not exceed 150 °C. Low-elevation airborne gravity gradient and magnetic data sets covering 5,012 line km, together with high-quality magnetotelluric data at 100 stations, provide both regional information about the thickness of the Deccan Traps and the occurrence of localized density heterogeneities and anomalous conductive zones in the vicinity of the hypocentral zone. Acquisition of airborne LiDAR data to obtain a high-resolution topographic model of the region has been completed over an area of 1,064 km2 centred on the Koyna seismic zone. Seismometers have been deployed in the granitic basement inside two boreholes and are planned in another set of six boreholes to obtain accurate hypocentral locations and constrain the disposition of fault zones.

Ganymede G1 & G2 Encounters - Interior of Ganymede

NASA Image and Video Library

1997-12-16

NASA's Voyager images are used to create a global view of Ganymede. The cut-out reveals the interior structure of this icy moon. This structure consists of four layers based on measurements of Ganymede's gravity field and theoretical analyses using Ganymede's known mass, size and density. Ganymede's surface is rich in water ice and Voyager and Galileo images show features which are evidence of geological and tectonic disruption of the surface in the past. As with the Earth, these geological features reflect forces and processes deep within Ganymede's interior. Based on geochemical and geophysical models, scientists expected Ganymede's interior to either consist of: a) an undifferentiated mixture of rock and ice or b) a differentiated structure with a large lunar sized "core" of rock and possibly iron overlain by a deep layer of warm soft ice capped by a thin cold rigid ice crust. Galileo's measurement of Ganymede's gravity field during its first and second encounters with the huge moon have basically confirmed the differentiated model and allowed scientists to estimate the size of these layers more accurately. In addition the data strongly suggest that a dense metallic core exists at the center of the rock core. This metallic core suggests a greater degree of heating at sometime in Ganymede's past than had been proposed before and may be the source of Ganymede's magnetic field discovered by Galileo's space physics experiments. http://photojournal.jpl.nasa.gov/catalog/PIA00519

Learning by Teaching: Implementation of a Multimedia Project in Astro 101

NASA Astrophysics Data System (ADS)

Perrodin, D.; Lommen, A.

2011-09-01

Astro 101 students have deep-seated pre-conceptions regarding such topics as the cause of moon phases or the seasons. Beyond exploring the topics in a learner-centered fashion, the "learning by teaching" philosophy enables students to truly master concepts. In order to make students teach the cause of moon phases, we created a multimedia project where groups of students taught other students and filmed the session. They were to produce a 10-minute final movie highlighting their teaching techniques and showing students in the process of learning the concepts. This "experiment" turned out to be a great success for a few reasons. First, students gained experience explaining conceptually-challenging topics, making them learn the material better. Additionally, they learned to apply learner-centered techniques, most likely learning to teach for the first time. Finally, this project provided the students a connection between the classroom and the rest of the college, making them responsible for applying and sharing their knowledge with their peers.

Explicitly modelled deep-time tidal dissipation and its implication for Lunar history

NASA Astrophysics Data System (ADS)

Green, J. A. M.; Huber, M.; Waltham, D.; Buzan, J.; Wells, M.

2017-03-01

Dissipation of tidal energy causes the Moon to recede from the Earth. The currently measured rate of recession implies that the age of the Lunar orbit is 1500 My old, but the Moon is known to be 4500 My old. Consequently, it has been proposed that tidal energy dissipation was weaker in the Earth's past, but explicit numerical calculations are missing for such long time intervals. Here, for the first time, numerical tidal model simulations linked to climate model output are conducted for a range of paleogeographic configurations over the last 252 My. We find that the present is a poor guide to the past in terms of tidal dissipation: the total dissipation rates for most of the past 252 My were far below present levels. This allows us to quantify the reduced tidal dissipation rates over the most resent fraction of lunar history, and the lower dissipation allows refinement of orbitally-derived age models by inserting a complete additional precession cycle.

NASA Human Spaceflight Architecture Team Cis-Lunar Analysis

NASA Technical Reports Server (NTRS)

Lupisella, M.; Bobskill, M. R.

2012-01-01

The Cis-Lunar Destination Team of NASA's Human Spaceflight Architecture Teait1 (HAT) has been perfom1ing analyses of a number of cis-lunar locations to infom1 architecture development, transportation and destination elements definition, and operations. The cis-lunar domain is defined as that area of deep space under the gravitation influence of the earth-moon system, including a set of orbital locations (low earth orbit (LEO]. geosynchronous earth orbit [GEO]. highly elliptical orbits [HEO]); earth-moon libration or "Lagrange·· points (EMLl through EMLS, and in particular, EMLI and EML2), and low lunar orbit (LLO). We developed a set of cis-lunar mission concepts defined by mission duration, pre-deployment, type of mission, and location, to develop mission concepts and the associated activities, capabilities, and architecture implications. To date, we have produced two destination operations J concepts based on present human space exploration architectural considerations. We have recently begun defining mission activities that could be conducted within an EM LI or EM L2 facility.

Autonomous Real-time Detection of Plumes and Jets from Moons and Comets

NASA Astrophysics Data System (ADS)

Wagstaff, Kiri L.; Thompson, David R.; Bue, Brian D.; Fuchs, Thomas J.

2014-10-01

Dynamic activity on the surface of distant moons, asteroids, and comets can manifest as jets or plumes. These phenomena provide information about the interior of the bodies and the forces (gravitation, radiation, thermal) they experience. Fast detection and follow-up study is imperative since the phenomena may be time-varying and because the observing window may be limited (e.g., during a flyby). We have developed an advanced method for real-time detection of plumes and jets using onboard analysis of the data as it is collected. In contrast to prior work, our technique is not restricted to plume detection from spherical bodies, making it relevant for irregularly shaped bodies such as comets. Further, our study analyzes raw data, the form in which it is available on board the spacecraft, rather than fully processed image products. In summary, we contribute a vital assessment of a technique that can be used on board tomorrow's deep space missions to detect, and respond quickly to, new occurrences of plumes and jets.

The composition and origin of the moon

NASA Technical Reports Server (NTRS)

Anderson, D. L.

1972-01-01

A model is presented of the moon as a high temperature condensate from the solar nebula. The Ca, Al, and Ti rich compounds condense first in a cooling nebula. The initial high temperature mineralogy is gehlenite, spinel, perovskite, Ca-Al-rich pyroxenes, and anorthite. Type 3 carbonaceous chondrites such as the Allende meteorite are composed primarily of these minerals and are highly enriched in refractories. These inclusions can yield basalt and anorthosite in the proportions required to eliminate the europium anomaly, leaving a residual spinel-melilite interior. The inferred high U content of the lunar interior, both from the Allende analogy and the high heat flow, indicates a high temperature interior. The model is consistent with extensive early, shallow melting at 3 A.E., and with high deep internal temperatures. It is predicted that the outer 250 km is rich in plagioclase and FeO. The low iron content of the interior raises the interior temperatures estimated from electrical conductivity by some 800 C.

Safe Laser Beam Propagation for Interplanetary Links

NASA Technical Reports Server (NTRS)

Wilson, Keith E.

2011-01-01

Ground-to-space laser uplinks to Earth–orbiting satellites and deep space probes serve both as a beacon and an uplink command channel for deep space probes and Earth-orbiting satellites. An acquisition and tracking point design to support a high bandwidth downlink from a 20-cm optical terminal on an orbiting Mars spacecraft typically calls for 2.5 kW of 1030-nm uplink optical power in 40 micro-radians divergent beams.2 The NOHD (nominal ocular hazard distance) of the 1030nm uplink is in excess of 2E5 km, approximately half the distance to the moon. Recognizing the possible threat of high power laser uplinks to the flying public and to sensitive Earth-orbiting satellites, JPL developed a three-tiered system at its Optical Communications Telescope Laboratory (OCTL) to ensure safe laser beam propagation through navigational and near-Earth space.

Triggered Slow Slip and Afterslip on the Southern Hikurangi Subduction Zone Following the Kaikōura Earthquake

NASA Astrophysics Data System (ADS)

Wallace, Laura M.; Hreinsdóttir, Sigrún; Ellis, Susan; Hamling, Ian; D'Anastasio, Elisabetta; Denys, Paul

2018-05-01

The 2016 MW7.8 Kaikōura earthquake ruptured a complex sequence of strike-slip and reverse faults in New Zealand's northeastern South Island. In the months following the earthquake, time-dependent inversions of Global Positioning System and interferometric synthetic aperture radar data reveal up to 0.5 m of afterslip on the subduction interface beneath the northern South Island underlying the crustal faults that ruptured in the earthquake. This is clear evidence that the far southern end of the Hikurangi subduction zone accommodates plate motion. The MW7.8 earthquake also triggered widespread slow slip over much of the subduction zone beneath the North Island. The triggered slow slip included immediate triggering of shallow (<15 km), short (2-3 weeks) slow slip events along much of the east coast, and deep (>30 km), long-term (>1 year) slow slip beneath the southern North Island. The southern Hikurangi slow slip was likely triggered by large (0.5-1.0 MPa) static Coulomb stress increases.

Study of sleeper’s impact on the deep-water pipeline lateral global buckling

NASA Astrophysics Data System (ADS)

Liu, Wenbin; Li, Bin

2017-08-01

Pipelines are the most important transportation way for offshore oil and gas, and the lateral buckling is the main global buckling form for deep-water pipelines. The sleeper is an economic and efficient device to trigger the lateral buckling in preset location. This paper analyzed the lateral buckling features for on-bottom pipeline and pipeline with sleeper. The stress and strain variation during buckling process is shown to reveal the impact of sleeper on buckling.

Breakup of last glacial deep stratification in the South Pacific.

PubMed

Basak, Chandranath; Fröllje, Henning; Lamy, Frank; Gersonde, Rainer; Benz, Verena; Anderson, Robert F; Molina-Kescher, Mario; Pahnke, Katharina

2018-02-23

Stratification of the deep Southern Ocean during the Last Glacial Maximum is thought to have facilitated carbon storage and subsequent release during the deglaciation as stratification broke down, contributing to atmospheric CO 2 rise. Here, we present neodymium isotope evidence from deep to abyssal waters in the South Pacific that confirms stratification of the deepwater column during the Last Glacial Maximum. The results indicate a glacial northward expansion of Ross Sea Bottom Water and a Southern Hemisphere climate trigger for the deglacial breakup of deep stratification. It highlights the important role of abyssal waters in sustaining a deep glacial carbon reservoir and Southern Hemisphere climate change as a prerequisite for the destabilization of the water column and hence the deglacial release of sequestered CO 2 through upwelling. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Composite Megathrust Rupture From Deep Interplate to Trench of the 2016 Solomon Islands Earthquake

NASA Astrophysics Data System (ADS)

Lee, Shiann-Jong; Lin, Tzu-Chi; Feng, Kuan-Fu; Liu, Ting-Yu

2018-01-01

The deep plate boundary has usually been recognized as an aseismic area, with few large earthquakes occurring at the 60-100 km depth interface. In contrast, we use a finite-fault rupture model to demonstrate that large slip in the 2016 M7.9 Solomon Islands earthquake may have originated from the deep subduction interface and propagated all the way up to the trench. The initial rupture occurred at a depth of about 100 km, forming a deep asperity and then propagating updip to the middle-depth large coseismic slip area. Our proposed source model indicates that the depth-varying rupture characteristics of this event could shift to deeper depths with respect to other subduction zones. This result also implied that the deep subducting plate boundary could also be seismogenic, which might trigger rupture at the typical middle-depth stress-locked zone and develop into rare composite megathrust events.

Fermi Observations of γ-Ray Emission from the Moon

NASA Astrophysics Data System (ADS)

Abdo, A. A.; Ackermann, M.; Ajello, M.; Atwoo, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bonamente, E.; Borgland, A. W.; Bottacini, E.; Bouvier, A.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Casandjian, J. M.; Cecchi, C.; Charles, E.; Chekhtman, A.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Dermer, C. D.; Digel, S. W.; Silva, E. do Couto e.; Drell, P. S.; Drlica-Wagner, A.; Dubois, R.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Fortin, P.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Gomez-Vargas, G. A.; Grenier, I. A.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Hays, E.; Hill, A. B.; Horan, D.; Hou, X.; Hughes, R. E.; Iafrate, G.; Jackson, M. S.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Knödlseder, J.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; Lovellette, M. N.; Lubrano, P.; Mazziotta, M. N.; McEnery, J. E.; Mehault, J.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A. A.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Naumann-Godo, M.; Nolan, P. L.; Norris, J. P.; Nuss, E.; Ohno, M.; Ohsugi, T.; Okumura, A.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Ozaki, M.; Paneque, D.; Panetta, J. H.; Parent, D.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Pivato, G.; Poon, H.; Porter, T. A.; Prokhorov, D.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Reposeur, T.; Rochester, L. S.; Roth, M.; Sadrozinski, H. F.-W.; Sanchez, D. A.; Sbarra, C.; Schalk, T. L.; Sgrò, C.; Share, G. H.; Siskind, E. J.; Spandre, G.; Spinelli, P.; Stawarz, Ł.; Takahashi, H.; Tanaka, T.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Uchiyama, Y.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vitale, V.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, D. L.; Wood, K. S.; Yang, Z.; Zimmer, S.

2012-10-01

We report on the detection of high-energy γ-ray emission from the Moon during the first 24 months of observations by the Fermi Large Area Telescope (LAT). This emission comes from particle cascades produced by cosmic-ray (CR) nuclei and electrons interacting with the lunar surface. The differential spectrum of the Moon is soft and can be described as a log-parabolic function with an effective cutoff at 2-3 GeV, while the average integral flux measured with the LAT from the beginning of observations in 2008 August to the end of 2010 August is F(>100\\ MeV) =(1.04+/- 0.01\\,{[statistical\\ error]}+/- 0.1\\,{[systematic\\ error]})\\times 10^{-6} cm-2 s-1. This flux is about a factor 2-3 higher than that observed between 1991 and 1994 by the EGRET experiment on board the Compton Gamma Ray Observatory, F(>100 MeV) ≈ 5 × 10-7 cm-2 s-1, when solar activity was relatively high. The higher γ-ray flux measured by Fermi is consistent with the deep solar minimum conditions during the first 24 months of the mission, which reduced effects of heliospheric modulation, and thus increased the heliospheric flux of Galactic CRs. A detailed comparison of the light curve with McMurdo Neutron Monitor rates suggests a correlation of the trends. The Moon and the Sun are so far the only known bright emitters of γ-rays with fast celestial motion. Their paths across the sky are projected onto the Galactic center and high Galactic latitudes as well as onto other areas crowded with high-energy γ-ray sources. Analysis of the lunar and solar emission may thus be important for studies of weak and transient sources near the ecliptic.

Moon Color Visualizations

NASA Technical Reports Server (NTRS)

1990-01-01

These color visualizations of the Moon were obtained by the Galileo spacecraft as it left the Earth after completing its first Earth Gravity Assist. The image on the right was acquired at 6:47 p.m. PST Dec. 8, 1990, from a distance of almost 220,000 miles, while that on the left was obtained at 9:35 a.m. PST Dec. 9, at a range of more than 350,000 miles. On the right, the nearside of the Moon and about 30 degrees of the far side (left edge) are visible. In the full disk on the left, a little less than half the nearside and more than half the far side (to the right) are visible. The color composites used images taken through the violet and two near infrared filters. The visualizations depict spectral properties of the lunar surface known from analysis of returned samples to be related to composition or weathering of surface materials. The greenish-blue region at the upper right in the full disk and the upper part of the right hand picture is Oceanus Procellarum. The deeper blue mare regions here and elsewhere are relatively rich in titanium, while the greens, yellows and light oranges indicate basalts low in titanium but rich in iron and magnesium. The reds (deep orange in the right hand picture) are typically cratered highlands relatively poor in titanium, iron and magnesium. In the full disk picture on the left, the yellowish area to the south is part of the newly confirmed South Pole Aitken basin, a large circular depression some 1,200 miles across, perhaps rich in iron and magnesium. Analysis of Apollo lunar samples provided the basis for calibration of this spectral map; Galileo data, in turn, permit broad extrapolation of the Apollo based composition information, reaching ultimately to the far side of the Moon.

KSC-2014-3193

NASA Image and Video Library

2014-07-21

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, NASA officials and Apollo astronauts visiting Launch Pad 39B with their families and friends preserve the moment with a group portrait. The group was at Kennedy for a ceremony renaming the Operations and Checkout Building for Apollo 11 astronaut Neil Armstrong, the first person to set foot on the moon. From left are NASA Administrator Charles Bolden, Neil's granddaughter Lily Armstrong, Neil's grandson Bryce Armstrong, Neil's son Mark Armstrong, Neil's former wife Janet Armstrong, Neil's son Rick Armstrong, Apollo 11 moonwalker Buzz Aldrin, Buzz's friend Judy Rice, Apollo astronaut Jim Lovell, Mike Collins' daughter Ann Starr, Apollo 11 command module pilot Mike Collins, Buzz's grandson Jeffrey Schuss, Jeffrey's wife April Schuss, Buzz's son-in-law Bruce Hanifan, Buzz's daughter Jan Aldrin, Buzz's son Andy Aldrin, and Center Director Bob Cabana. The pad is being modified to support the agency's new Orion spacecraft which will lift off atop the Space Launch System rocket. Orion is designed to take humans farther than they’ve ever gone before, serving as the exploration vehicle that will carry astronauts to deep space and sustain the crew during travel to destinations such as an asteroid or Mars. The visit of the former astronauts was part of NASA's 45th anniversary celebration of the Apollo 11 moon landing. As the world watched, Neil Armstrong and Neil Aldrin landed in the moon's Sea of Tranquility aboard the lunar module Eagle on July 20, 1969. Meanwhile, crewmate Michael Collins orbited above in the command module Columbia. For more, visit http://www.nasa.gov/press/2014/july/nasa-honors-historic-first-moon-landing-eyes-first-mars-mission. Photo credit: NASA/Kim Shiflett

Antarctic icequakes triggered by the 2010 Maule earthquake in Chile

NASA Astrophysics Data System (ADS)

Peng, Zhigang; Walter, Jacob I.; Aster, Richard C.; Nyblade, Andrew; Wiens, Douglas A.; Anandakrishnan, Sridhar

2014-09-01

Seismic waves from distant, large earthquakes can almost instantaneously trigger shallow micro-earthquakes and deep tectonic tremor as they pass through Earth's crust. Such remotely triggered seismic activity mostly occurs in tectonically active regions. Triggered seismicity is generally considered to reflect shear failure on critically stressed fault planes and is thought to be driven by dynamic stress perturbations from both Love and Rayleigh types of surface seismic wave. Here we analyse seismic data from Antarctica in the six hours leading up to and following the 2010 Mw 8.8 Maule earthquake in Chile. We identify many high-frequency seismic signals during the passage of the Rayleigh waves generated by the Maule earthquake, and interpret them as small icequakes triggered by the Rayleigh waves. The source locations of these triggered icequakes are difficult to determine owing to sparse seismic network coverage, but the triggered events generate surface waves, so are probably formed by near-surface sources. Our observations are consistent with tensile fracturing of near-surface ice or other brittle fracture events caused by changes in volumetric strain as the high-amplitude Rayleigh waves passed through. We conclude that cryospheric systems can be sensitive to large distant earthquakes.

NASA's Space Launch System: A New Capability for Science and Exploration

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Creech, Stephen D.; May, Todd A.

2014-01-01

NASA's Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will launch the Orion Multi-Purpose Crew Vehicle (MPCV) and other high-priority payloads into deep space. Its evolvable architecture will allow NASA to begin with human missions beyond the Moon and then go on to transport astronauts or robots to distant places such as asteroids and Mars. Developed with the goals of safety, affordability, and sustainability in mind, SLS will start with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration. This paper will explain how NASA will execute this development within flat budgetary guidelines by using existing engines assets and heritage technology, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability, and will detail the progress that has already been made toward a first launch in 2017. This paper will also explore the requirements needed for human missions to deep-space destinations and for game-changing robotic science missions, and the capability of SLS to meet those requirements and enable those missions, along with the evolution strategy that will increase that capability. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has worked together to create the Global Exploration Roadmap, which outlines paths towards a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for extended trips to asteroids, the Moon, and Mars. SLS also offers substantial capability to support robotic science missions, offering benefits such as improved mass margins and radiation mitigation, and reduced mission durations. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust space launch capability to deliver sustainable solutions for advanced exploration.

NASA's Space Launch System: A New Capability for Science and Exploration

NASA Technical Reports Server (NTRS)

Crumbly, Christopher M.; May, Todd A.; Robinson, Kimberly F.

2014-01-01

The National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will launch the Orion Multi-Purpose Crew Vehicle (MPCV) and other high-priority payloads into deep space. Its evolvable architecture will allow NASA to begin with human missions beyond the Moon and then go on to transport astronauts or robots to distant places such as asteroids and Mars. Developed with the goals of safety, affordability, and sustainability in mind, SLS will start with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration. This paper will explain how NASA will execute this development within flat budgetary guidelines by using existing engines assets and heritage technology, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability, and will detail the progress that has already been made toward a first launch in 2017. This paper will also explore the requirements needed for human missions to deep-space destinations and for game-changing robotic science missions, and the capability of SLS to meet those requirements and enable those missions, along with the evolution strategy that will increase that capability. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has worked together to create the Global Exploration Roadmap, which outlines paths towards a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for extended trips to asteroids, the Moon, and Mars. SLS also offers substantial capability to support robotic science missions, offering benefits such as improved mass margins and radiation mitigation, and reduced mission durations. The SLS rocket, using significantly higher characteristic energy (C3), can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust space launch capability to deliver sustainable solutions for advanced exploration.

Introduction to Japanese exploration study to the moon

NASA Astrophysics Data System (ADS)

Hashimoto, T.; Hoshino, T.; Tanaka, S.; Otake, H.; Otsuki, M.; Wakabayashi, S.; Morimoto, H.; Masuda, K.

2014-11-01

The Japan Aerospace Exploration Agency (JAXA) views the lunar lander SELENE-2 as the successor to the SELENE mission. In this presentation, the mission objectives of SELENE-2 are shown together with the present design status of the spacecraft. JAXA launched the Kaguya (SELENE) lunar orbiter in September 2007, and the spacecraft observed the Moon and a couple of small satellites using 15 instruments. As the next step in lunar exploration, the lunar lander SELENE-2 is being considered. SELENE-2 will land on the lunar surface and perform in-situ scientific observations, environmental investigations, and research for future lunar utilization including human activity. At the same time, it will demonstrate key technologies for lunar and planetary exploration such as precise and safe landing, surface mobility, and overnight survival. The lander will carry laser altimeters, image sensors, and landing radars for precise and safe landing. Landing legs and a precisely controlled propulsion system will also be developed. A rover is being designed to be able to travel over a wide area and observe featured terrain using scientific instruments. Since some of the instruments require long-term observation on the lunar surface, technology for night survival over more than 2 weeks needs to be considered. The SELENE-2 technologies are expected to be one of the stepping stones towards future Japanese human activities on the moon and to expand the possibilities for deep space science.

Saturn's secrets revealed - A special report

NASA Astrophysics Data System (ADS)

Sutton, C.

1980-11-01

Scientific results of the encounter of Voyager 1 with Saturn are reported. Instruments on the Voyager spacecraft, which was launched on September 5, 1977 and flew within 124,200 km of the Saturn cloud tops on November 12, 1980, revealed the presence of several hundred rings within the six visible from earth, as well as eccentric rings, braiding and clumps within the narrow F ring, and spoke-like structures in the B ring. During its flight beneath the ring plane, Voyager 1 also discovered that the rings extend toward the visible surface of the cloud tops, and are composed of ice chunks or silicate with an icy coating about a meter in diameter. Observations of Titan revealed the satellite to have a dense atmosphere, composed primarily of molecular nitrogen, with as many as three layers of haze above the cloud tops. Three additional moons of Saturn were discovered apparently focusing ring particles, and the moon Janus, discovered from earth in 1966, was shown to be actually two moons. Close approaches to other Saturn satellites show Mimas, Tethys, Dione and Rhea to be heavily cratered, icy bodies, some with features indicating they had been struck by objects almost large enough to shatter them. Surface features on Saturn, which is covered by a deep layer of haze, and the details of the Saturn magnetosphere have also been observed.

"First Convention of Lunar Explorers" - Invitation to the media

NASA Astrophysics Data System (ADS)

2001-03-01

The first LUNEX Convention will bring together lunar explorers from all backgrounds, including professionals, amateur space enthusiasts and interested visitors from the public. During the Convention numerous oral presentations will prompt detailed discussions on all aspects of future lunar exploration: the Moon as a geology laboratory or an astronomical platform; the knowledge of lunar geography needed to land and move on the surface; the implications of finding water-ice on the Moon and whether this might be detected by forthcoming missions; the architecture of lunar habitats; what would be needed in the future for the Moon to support life; cultural and social aspects; and the scientific motivation for returning to the Moon. The Convention will also be the main public event in 2001 at which SMART-1 is presented. SMART-1, due to be launched in 2002 will test solar electric propulsion and other innovative approaches for future deep space probes. It is the first European satellite to be sent towards the Moon. Visitors to the Palais de la Découverte will be able to view a model of SMART-1. On 9 March, at 09:00, the media is invited to hear about the LUNEX objectives and activities and to learn about the European Space Agency’s SMART-1 mission within the broader context of ESA’s Planetary Exploration Programme. Background information on LUNEX The Lunar Explorers Society (LUNEX) is an international organization created by 200 founder members in July 2000. LUNEX was founded at the end of the 4th Conference on Exploration and Utilisation of the Moon (ICEUM4), organised by ESA and the International Lunar Exploration Working Group (ILEWG). Its aim is to promote the exploration of the Moon for the benefit of humanity, bridging the gap between space agencies and the general public to promote planetary exploration and space. The Lunar Explorers Society invites all interested individuals to become members. Background information on SMART-1 SMART-1 is the first of ESA’s SMART (Small Mission for Advanced Research and Technology) missions under the Horizon 2000 Scientific Programme. SMART-1 will be launched in October 2002 on board an Ariane-5 rocket as an auxiliary payload. The mission’s primary objective is to flight-test solar electric primary propulsion on a Moon voyage, preparing crucial new technology for ESA’s Bepi-Colombo mission to Mercury. Other new technologies for spacecraft and instruments will also be tested. It will be the first time that Europe sends a spacecraft to the Moon. Besides relying on solar electric primary propulsion to leave the Earth and reach the Moon, the spacecraft will also carry out a complete programme of scientific observations in lunar orbit. During the cruise phase to reach the Moon, the instruments will be tested by observing the Earth and celestial targets. Note to editors: Members of the media are invited to attend the complete conference free of charge. The sessions planned for 9 March are of particularly great interest for media participation. Individual interviews and a web forum will be organized. Media representatives wishing to take part in the Press Conference on 9 March at 09:00 (in English and French) are kindly requested to fill out and return the attached accreditation request by fax to: +33(0)1.53.69.76.90.

Disturbance of deep-sea environments induced by the M9.0 Tohoku Earthquake

PubMed Central

Kawagucci, Shinsuke; Yoshida, Yukari T.; Noguchi, Takuroh; Honda, Makio C.; Uchida, Hiroshi; Ishibashi, Hidenori; Nakagawa, Fumiko; Tsunogai, Urumu; Okamura, Kei; Takaki, Yoshihiro; Nunoura, Takuro; Miyazaki, Junichi; Hirai, Miho; Lin, Weiren; Kitazato, Hiroshi; Takai, Ken

2012-01-01

The impacts of the M9.0 Tohoku Earthquake on deep-sea environment were investigated 36 and 98 days after the event. The light transmission anomaly in the deep-sea water after 36 days became atypically greater (∼35%) and more extensive (thickness ∼1500 m) near the trench axis owing to the turbulent diffusion of fresh seafloor sediment, coordinated with potential seafloor displacement. In addition to the chemical influx associated with sediment diffusion, an influx of 13C-enriched methane from the deep sub-seafloor reservoirs was estimated. This isotopically unusual methane influx was possibly triggered by the earthquake and its aftershocks that subsequently induced changes in the sub-seafloor hydrogeologic structures. The whole prokaryotic biomass and the development of specific phylotypes in the deep-sea microbial communities could rise and fall at 36 and 98 days, respectively, after the event. We may capture the snap shots of post-earthquake disturbance in deep-sea chemistry and microbial community responses. PMID:22355782

Terrestrial aftermath of the Moon-forming impact.

PubMed

Sleep, Norman H; Zahnle, Kevin J; Lupu, Roxana E

2014-09-13

Much of the Earth's mantle was melted in the Moon-forming impact. Gases that were not partially soluble in the melt, such as water and CO2, formed a thick, deep atmosphere surrounding the post-impact Earth. This atmosphere was opaque to thermal radiation, allowing heat to escape to space only at the runaway greenhouse threshold of approximately 100 W m(-2). The duration of this runaway greenhouse stage was limited to approximately 10 Myr by the internal energy and tidal heating, ending with a partially crystalline uppermost mantle and a solid deep mantle. At this point, the crust was able to cool efficiently and solidified at the surface. After the condensation of the water ocean, approximately 100 bar of CO2 remained in the atmosphere, creating a solar-heated greenhouse, while the surface cooled to approximately 500 K. Almost all this CO2 had to be sequestered by subduction into the mantle by 3.8 Ga, when the geological record indicates the presence of life and hence a habitable environment. The deep CO2 sequestration into the mantle could be explained by a rapid subduction of the old oceanic crust, such that the top of the crust would remain cold and retain its CO2. Kinematically, these episodes would be required to have both fast subduction (and hence seafloor spreading) and old crust. Hadean oceanic crust that formed from hot mantle would have been thicker than modern crust, and therefore only old crust underlain by cool mantle lithosphere could subduct. Once subduction started, the basaltic crust would turn into dense eclogite, increasing the rate of subduction. The rapid subduction would stop when the young partially frozen crust from the rapidly spreading ridge entered the subduction zone. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Elemental Fractionation During Rapid Accretion of the Moon Triggered by a Giant Impact

NASA Technical Reports Server (NTRS)

Abe, Y.; Zahnle, K. J.; Hashimoto, A.

1998-01-01

Recently, Ida et al. made an N-body simulation of lunar accretion from a protolunar disk formed by a giant impact. One of their important conclusions is that the accretion time of the Moon is as short as one month. Such rapid accretion is a necessary consequence of the high surface density of a lunar mass disk accreting just beyond the Roche limit (about 3Re); the Safronov accretion time (a few days) is even shorter. The energy of accretion always exceeds the gravitational binding energy of newly arriving matter. Hence, without an energy sink, the accreting body is thermally unstable. For the Earth and other planets, radiation acts as the sink. However, in such a short accretion time, the Moon cannot radiate the accretional energy. Even radiating at a silicate cloudtop temperature of roughly 2000 K, it would take more than 100 yr to radiatively cool the Moon. The plausible alternative heat sinks are heat capacity, latent heat of vaporization, and thermal escape of the gas to space (i.e., hydrodynamic blowoff). The latter becomes plausible for the Moon because the scale height at 2000 K (about 300 km) is a significant fraction of the lunar radius. The early stages of lunar (or "lunatesimal") growth release relatively little energy and can occur simply by heating the material, especially if the accreting material is originally cold. However, the material is unlikely to be cold, because the disk itself is hot and cooling time is long, while the lunar accretion time iss very short. Therefore, the moon is likely to accrete condensed material just after it condenses. Accordingly, the newly accreted material will be on the verge of vaporization and will have very little heat capacity to spare. The immediate heat sink is the latent heat of vaporization. Most of the vapor will escape from the moon, because the thermal energy in the gas can be used to drive escape. However, vaporization is generally incomplete. the latent heat of vaporization exceeds the energy of accretion. Viewed globally, the accretional energy is about half the energy required to vaporize the entire Moon. Thus to first approximation, half of the Moon-forming material can be vaporized and lost during accretion. During this process, we would expect preferential loss of relatively volatile elements. Escape will retard the rate of accretion. To test these ideas, we computed detailed models of the thermal state of the Moon during accretion. We pay special attention to the structure of the silicate atmosphere and its loss rate by calculating the chemical species at equilibrium. We used the PHEQ program which includes 12 elements (H,O,C,Mg,Si,Fe,Ca, Al, Na,Ti, and N.) and 272 compounds (including ionic compounds). Because of the large heats of vaporization and ionization, the adiabatic atmosphere is nearly isothermal and massive escape is expected. The pressure of the atmosphere is determined by the balance between vaporization of a accreting material and escape. If the accretion time is one month, a 0.3 bar atmosphere is expected. Elemental fractionation depends strongly on the temperature of the accreting material. The initial temperature of the material can be estimated from the condition of gravitational instability in the protolunar disk. As shown by Ida et al, accretion starts when gravitational instability occurs when more than 99% of the material condenses. At this point, all of Ca, Al, Si, Mg, and Fe, and 95% of Na (probably K also), are in condensed phases. If the moon is formed from the accretion of such material, volatile elements such as Na, and K are retained by the moon only early in accretion. At later times, K and Na are lost and a fraction of the MG, Si and Fe is lost. However, refractory elements such as Ca and Al are retained and so achieve a mild degree (factor 2) of superabundance.

SMART-1 - the lunar adventure begins

NASA Astrophysics Data System (ADS)

2003-08-01

On the one hand, SMART-1 will test new state-of-the art instruments and techniques essential to ambitious future interplanetary missions, such as a solar-electric primary propulsion system. On the other, SMART-1 will answer pending scientific questions, addressing key issues such as the Moon's formation, its precise mineralogical composition, and the presence and quantity of water. These data will help scientists to understand the Earth-Moon system and Earth-like planets, and will also provide invaluable information when considering a long-lasting human presence on the Moon. On 15 July 2003, SMART 1 was shipped to the European launch base in Kourou, French Guiana, where it is being prepared for its launch, due to take place on an Ariane-5 rocket on 29 August 2003 (Central European Summer Time). For the first time, SMART-1 will combine the power obtained by solar-electric propulsion - never used before by Europe as a main propulsion system - with lunar gravity. It will not follow a direct path to cross the 400 000 kilometres distance between the Earth and the Moon. Instead, from an elliptical orbit around the Earth where it is placed by the rocket, SMART-1 will gradually expand the orbit in a spiral pathway that will bring it closer to the Moon every month. Finally, the Moon’s gravitational field will capture the spacecraft. SMART-1 will not land on the Moon, but will make its observations from orbit, obtaining a global view. When it reaches its destination, in December 2004, it will enter orbit around the Moon and make measurements for a period of six months possibly extended to one year. Why the Moon? Water, minerals, and a violent origin “Our knowledge of the Moon is still surprisingly incomplete,” says Bernard Foing, ESA’s SMART-1 Project Scientist. “We still want to know how the Earth-Moon system formed and evolved, as well as the role of geophysical processes such as volcanism, tectonics, cratering, or erosion in shaping the Moon. And, of course, in preparation for future lunar and planetary exploration, we need to find resources and landing sites.” So, there are many unsolved questions about the Moon, even though six NASA Apollo missions and three unmanned Soviet spacecraft have landed on it and brought back rock samples. The far side of the Moon --the one that never faces Earth-- and the polar regions remain fairly unexplored. The existence of water on the Moon has also never been confirmed, although two orbiters in the 1990s found indirect evidence. We are not even sure how the Moon was formed. According to the most accepted theory, 4500 million years ago an asteroid the size of Mars collided with our planet, and the vapourised debris that went into space condensed to form the Moon. SMART-1 will map the Moon's topography, as well as the surface distribution of minerals such as pyroxenes, olivines, and feldspars. Also, an X-ray detector will identify key chemical elements in the lunar surface. These data will allow scientists to reconstruct the geological evolution of the Moon, and to search for traces of the impact with the giant asteroid. If the collision theory is right, the Moon should contain less iron than the Earth, in proportion to lighter elements such as magnesium and aluminium. By gauging the relative amounts of chemical elements comprehensively for the very first time, SMART-1 can make a significant contribution in resolving this issue. As for water, if it exists, it must be in the form of ice in places always hidden from the Sun. In such places, the temperature will never rise above -170ºC. Dark places like that could exist in the bottoms of small craters in the polar regions. Peering into these craters is maybe the trickiest task that the SMART-1 scientists have set themselves. They will look for the infrared signature of water- ice. It will be difficult because no direct light falls in those areas, but rays from nearby crater rims, catching the sunshine, may light the ice sufficiently for SMART-1 instruments to see it. New technologies to prepare for future interplanetary missions Future scientific missions will greatly profit from the technologies being tested on SMART-1. Solar-electric primary propulsion is a new propulsion technique based on so-called 'ion engines' that feed on electricity derived from solar panels. It is a technique that has only ever been used once before. These engines provide a very gentle thrust, but they work for years while conventional, more powerful chemical rockets burn for only a few minutes. Ion engines offer key advantages. They need considerably less propellant than chemical propulsion, which means less weight at launch and more mass available for scientific instruments and payload. Ion engines open the door to truly deep space exploration. They slash the time for interplanetary flight: although they provide less thrust they can last for years. The ion tortoise will therefore eventually overtake the chemical hare. Moreover, another application of the gentle thrust provided by electric propulsion allows very accurate spacecraft attitude control, a skill that will be useful for scientific missions that require highly precise and undisturbed pointing. Future ESA science missions will rely on ion engines. SMART-1 will also test new miniaturisation techniques that save space and economise on mass: in space, less mass per instrument enables scientists to have more instruments on board, so more science. The SMART-1 payload consists of a dozen technological and scientific investigations performed by seven instruments weighing only 19 kilograms in total. For example, the X-ray telescope D-CIXS, consists of a cube just 15 centimetres wide and weighing less than 5 kilograms. The ultra-compact electronic camera, AMIE, weighs no more than an amateur’s camera. New navigation and space-communication techniques will also be tested. An experiment called OBAN, based on images from the miniature camera AMIE and the star trackers, is the first step towards future 'autonomous' spacecraft. In a not-too-distant future, scientific satellites will be able to 'find their way' with a minimum of ground control, just by using stars and other celestial objects to guide themselves along predefined paths. As for communications, engineers need to develop new and efficient ways to communicate with Earth from deep space, for interplanetary missions that are long or go far. SMART-1 will test both very short radio waves (called Ka band, with the instrument KaTE) and a laser experiment to try to communicate with the Earth using a laser beam, instead of traditional radio frequencies. ESA already has laser links with telecommunications satellites from an optical ground station on Tenerife, in Spain’s Canary Islands. Aiming the beam becomes much more difficult if, like SMART-1, the spacecraft is far away and moving rapidly. Scientists hope that the on-board camera AMIE will see Tenerife aglow with laser light.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aguiar, Ana C.; Chao, Kevin; Beroza, Gregory C.

In this paper, we compare low-frequency earthquakes (LFEs) from triggered and ambient tremor under the southern Central Range, Taiwan. We apply the PageRank algorithm used by Aguiar and Beroza (2014) that exploits the repetitive nature of the LFEs to find repeating LFEs in both ambient and triggered tremor. We use these repeaters to create LFE templates and find that the templates created from both tremor types are very similar. To test their similarity, we use both interchangeably and find that most of both the ambient and triggered tremor match the LFE templates created from either data set, suggesting that LFEsmore » for both events have a common origin. Finally, we locate the LFEs by using local earthquake P wave and S wave information and find that LFEs from triggered and ambient tremor locate to between 20 and 35 km on what we interpret as the deep extension of the Chaochou-Lishan Fault.« less

Vice President Pence Visits NASA's Marshall Space Flight Center

NASA Image and Video Library

2017-09-25

Vice President Mike Pence offered his thanks Monday to employees working on NASA’s human spaceflight programs during a tour of the agency’s Marshall Space Flight Center in Huntsville, Alabama. The Vice President saw the progress being made on NASA’s Space Launch System (SLS), the world’s most powerful deep space rocket, that will send astronauts on missions around the Moon and ultimately to Mars. He also visited Marshall’s Payload Operations Integration Center, where the agency manages all research aboard the International Space Station.

Magnetism and the interior of the moon

NASA Technical Reports Server (NTRS)

Dyal, P.; Parkin, C. W.; Daily, W. D.

1974-01-01

The application of lunar magnetic field measurements to the study of properties of the lunar crust and deep interior is reviewed. Following a brief description of lunar magnetometers and the lunar magnetic environment, measurements of lunar remanent fields and their interaction with the solar plasma are discussed. The magnetization induction mode is considered with reference to lunar magnetic permeability and iron abundance calculations. Finally, electrical conductivity and temperature calculations from analyses of poloidal induction, for data taken in both the solar wind and in the geomagnetic tail, are reviewed.

The First Deep Space Cubesat Broadband IR Spectrometer, Lunarcubes, and the Search for Lunar Volatiles

NASA Technical Reports Server (NTRS)

Clark, P. E.; Malphrus, Ben; Reuter, Dennis; MacDowall, Robert; Folta, David; Hurford, Terry; Brambora, Cliff; Farrell, William

2017-01-01

BIRCHES is the compact broadband IR spectrometer of the Lunar Ice Cube mission. Lunar Ice Cube is one of 13 6U cubesats that will be deployed by EM1 in cislunar space, qualifying as lunarcubes. The LunarCube paradigm is a proposed approach for extending the affordable CubeSat standard to support access to deep space via cis-lunar/lunar missions. Because the lunar environment contains analogs of most solar system environments, the Moon is an ideal target for both testing critical deep space capabilities and understanding solar system formation and processes. Effectively, as developments are occurring in parallel, 13 prototype deep space cubesats are being flown for EM1. One useful outcome of this 'experiment' will be to determine to what extent it is possible to develop a lunarcube 'bus' with standardized interfaces to all subsystems using reasonable protocols for a variety of payloads. The lunar ice cube mission was developed as the test case in a GSFC R&D study to determine whether the cubesat paradigm could be applied to deep space, science requirements driven missions, and BIRCHES was its payload. JPL's Lunar Flashlight, and Arizona State University's LunaH-Map, both also EM1 lunar orbiters, will also be deployed from EM1 and provide complimentary observations to be used in understanding volatile dynamics in the same time frame.

SMART-1 celebrates its first year in space

NASA Astrophysics Data System (ADS)

2004-09-01

The ion engine went into action three days after launch and slowly placed SMART-1 safely above the radiation belts that surround the Earth. From there, SMART-1 started spiralling around our planet to eventually come closer, through ever wider orbits, to the so-called ‘Moon capture’ point. During this transfer phase, the ion engine fired its thrusters for periods of several days to progressively raise its apogee (the maximum altitude of its orbit) to the orbit of the Moon. So far, the SMART-1 ion engine has operated for about 3300 hours and covered a distance of some 78 million kilometres, with only 52 kilograms of propellant. With this successful demonstration, SMART-1 is paving the way for future deep-space missions, using a solar- electric engine as primary propulsion. It will be applied to long, energy-demanding interplanetary missions in the Solar System, reducing the size and cost of propulsion systems, while increasing manoeuvrability and the mass available for scientific instrumentation. ESA plans to use primary solar-electric propulsion for its future BepiColombo and Solar Orbiter missions. During its first year in space, SMART-1 has also successfully tested new space communication techniques. For the first time, SMART-1 has used very short radio waves (called Ka band at 32 Gigahertz, with the KaTE instrument) to communicate with Earth. These enable far more information to be transmitted over deep space than the commonly used frequencies and in a shorter period of time. Another SMART-1 achievement is the successful testing of a laser communication link experiment with ESA’s optical ground station in Tenerife, Canary Islands in February of this year. This laser technology, in which Europe is a leader, has already been applied to telecommunications satellites, but this was the first time a laser link had been used to communicate with a distant, rapidly moving spacecraft. Both techniques will be crucial for future science missions where huge amounts of scientific data have to be transferred back to Earth over large distances in space. During its cruise, SMART-1’s miniaturised payload, consisting of seven instruments weighing only 19 kilograms in total, has been tested. All instruments onboard SMART-1 were operated and performed successfully in a number of science experiments. This was excellent preparation for the next phase of the SMART-1 mission: an unprecedented scientific study of the Moon, exploring in-depth the mysteries of our Earth’s natural satellite. With all these achievements to celebrate after its first year in space, SMART-1 is now preparing for the next big milestone, the lunar capture which is expected to take place less than two months from now. Note for editors: SMART-1 was launched on 27 September 2003 from Kourou, Europe’s spaceport in French Guiana, onboard an Ariane-5 rocket. It is the first in a series of ‘Small Missions for Advanced Research in Technology’, designed to demonstrate innovative and key technologies for future deep-space science missions. In addition to its technological objectives, SMART-1 is Europe’s first lunar mission and will perform a detailed scientific study of the Moon.

Meltwater routing and the Younger Dryas

DOE PAGES

Condron, Alan; Winsor, Peter

2012-12-04

The Younger Dryas -- the last major cold episode on Earth -- is generally considered to have been triggered by a meltwater flood into the North Atlantic. The prevailing hypothesis, proposed by Broecker et al. [1989 Nature 341:318–321] more than two decades ago, suggests that an abrupt rerouting of Lake Agassiz overflow through the Great Lakes and St. Lawrence Valley inhibited deep water formation in the subpolar North Atlantic and weakened the strength of the Atlantic Meridional Overturning Circulation (AMOC).More recently, Tarasov and Peltier [2005 Nature 435:662–665] showed that meltwater could have discharged into the Arctic Ocean via the Mackenziemore » Valley ~4,000 km northwest of the St. Lawrence outlet. Here we use a sophisticated, high-resolution, ocean sea-ice model to study the delivery of meltwater from the two drainage outlets to the deep water formation regions in the North Atlantic. Unlike the hypothesis of Broecker et al., freshwater from the St. Lawrence Valley advects into the subtropical gyre ~3,000 km south of the North Atlantic deep water formation regions and weakens the AMOC by <15%. In contrast, narrow coastal boundary currents efficiently deliver meltwater from the Mackenzie Valley to the deep water formation regions of the subpolar North Atlantic and weaken the AMOC by >30%. We conclude that meltwater discharge from the Arctic, rather than the St. Lawrence Valley, was more likely to have triggered the Younger Dryas cooling.« less

Cassini Imaging of Iapetus and Solution of the Albedo Asymmetry Enigma

NASA Astrophysics Data System (ADS)

Denk, Tilmann; Spencer, John

2014-05-01

Cassini imaging of Iapetus during one close and several more distant flybys mainly in the first years of the mission revealed an alien and often unique landscape of this third-largest moon in the Saturnian system [1]. The data show numerous impact craters on the bright and dark terrain, equator-facing dark and pole-facing bright crater walls, huge impact basins, rather minor endogenic geologic features, a non-spherical, but ellipsoidal shape, a giant ridge which spans across half of Iapetus' circumference exactly along the equator, a newly detected global 'color dichotomy' presumably formed by dust from retrograde irregular moons, and of course the famous extreme global albedo asymmetry which has been an enigma for more than three centuries. Revealing the cause of this 'albedo dichotomy' enigma of Iapetus, where the trailing side and poles are more than 10x brighter than the leading side, was one of the major tasks for the Cassini mission. It has now been solved successfully. In the mid-1970es, deposition of exogenic dark material on the leading side, originating from outer retrograde moon Phoebe, was proposed as the cause. But this alone could not explain the global shape, sharpness, and complexity of the transition between Iapetus' bright and dark terrain. Mainly with Cassini spectrometer (CIRS) and imaging (ISS) data, all these characteristics and the asymmetry's large amplitude are now plausibly explained by runaway global thermal migration of water ice, triggered by the deposition of dark material on the leading hemisphere. This mechanism is unique to Iapetus among the Saturnian satellites for many reasons. Most important are Iapetus' slow rotation which produces unusually high daytime temperatures and water ice sublimation rates, and the size (gravity) of Iapetus which is small enough for global migration of water ice but large enough that much of the ice is retained on the surface [2]. References: [1] Denk, T., Neukum, G., Roatsch, Th., Porco, C.C., Burns, J.A., Galuba, G.G., Schmedemann, N., Helfenstein, P., Thomas, P.C., Wagner, R.J., West, R.A. (2010): Iapetus: Unique Surface Properties and a Global Color Dichotomy from Cassini Imaging. Science 327, no. 5964, 435-439. [2] Spencer, J.R., Denk, T. (2010): Formation of Iapetus's Extreme Albedo Dichotomy by Exogenically-Triggered Thermal Migration of Water Ice. Science 327, no. 5964, 432-435.

Search for hydraulic connectivity between surface reservoirs and surrounding aquifers in the reservoir-triggered seismic environment (Koyna region, India) using hydrochemical and isotopic signatures

NASA Astrophysics Data System (ADS)

Reddy, D. V.; Nagabhushanam, P.

2016-01-01

Triggered seismicity is an accepted hypothesis in the present days. However, detailed hydrogeological investigations are lacking in the well-known reservoir-triggered seismic (RTS) zones. Here, we made an attempt to understand the direct linkage between the well-known Koyna-Warna reservoirs believed to be under the RTS zone (situated in the Deccan volcanic province (DVP), India) and the surrounding groundwater system up to 250 m deep from the ground surface. Seismic activity in the region started soon after the impoundment of water in the Koyna reservoir and being continued over the last four and a half decades. Though researchers have carried out numerous studies on the Koyna seismicity, no hydrogeological investigations were attempted. Hence, hydrogeological, hydrochemical, and isotopic investigations were carried out for 7 years on groundwaters from 15 deep bore wells (up to 250 m) and two surface reservoir waters to elucidate the direct hydraulic connectivity between them. No appreciable seasonal change was observed in piezometric heads of the artesian wells, but the semi-artesian wells did show fluctuation of ~2 to 12 m during different years, which did not have any relation with the reservoir water levels. No considerable seasonal change in hydrochemistry was observed in individual wells due to the confined nature of the aquifers. The hydrochemical and δ18O data of the studied deep groundwaters and reservoir waters, being different from each other, rule out the possibility of direct hydraulic connectivity between them and surrounding groundwater (up to 250 m), even though favorable topographic conditions exist for linkage. The radiocarbon ages, being incomparable between different well waters, support the inference drawn from hydrochemistry and stable isotope data.

Destabilization of a Clay-Rich Slope by Rainfall : Monitoring of Precursons on an Hectometric Sliding Surface

NASA Astrophysics Data System (ADS)

Doan, M. L.; Bièvre, G.; Jongmans, D.; Helmstetter, A.; Radiguet, M.

2016-12-01

The Avignonet landslide is an active clay landslide near Grenoble, France, and therefore one of the monitored site of OMIV observatory. Previous geophysical investigation, including borehole drilling and surface geophysics proved that the landslide deformation is accommodated by several localized shear zones. The shallowest shear zone is about 5 m deep and extends over 100 m. Several sensors monitor the landslide. They record several precursors prior to a major disturbance of the landslide in autumn 2012, that affects all sensors in the landslide for several months. After major rainfalls, the two piezometers located near the 5 m deep interface got larger impulsional response to rainfall. The moderate rainfalls of Oct 26th caused the hydraulic head both reached a plateau before experiencing a sudden change, triggered by the small rainfall of Oct 31st. It's not the bigger rainfall that induced the disturbance. It was not the first rainfall neither.Other sensors suggest that the destabilization of the landslide was progressive. Spontaneous potential sensors regularly spaced within the 100 m wide sensors begin to separate after Oct 28th, suggesting a landslide wide precursor. Repeated microseismic events, of high frequency, suggesting a local origin, are more frequent. Their occurrence peaks after the small rainfall of Oct 29th and again on Oct 31st, before the rainfall that triggered the disturbance. They stop at the same time as sudden change in piezometric data. Despite the lack of displacement sensor, it is assumed that the 5 m deep shear zone slipped on Oct 31st, since it affects the piezometer sampling this interface. The data shows a progressive path towards destabilization. Especially, triggering of the landslide disturbances is associated to the cumulative effect of seismic activity and rainfall, even minor. This suggests a hydromechanical process.

SKYLAB II - Making a Deep Space Habitat from a Space Launch System Propellant Tank

NASA Technical Reports Server (NTRS)

Griffin, Brand N.; Smitherman, David; Kennedy, Kriss J.; Toups, Larry; Gill, Tracy; Howe, A. Scott

2012-01-01

Called a "House in Space," Skylab was an innovative program that used a converted Saturn V launch vehicle propellant tank as a space station habitat. It was launched in 1973 fully equipped with provisions for three separate missions of three astronauts each. The size and lift capability of the Saturn V enabled a large diameter habitat, solar telescope, multiple docking adaptor, and airlock to be placed on-orbit with a single launch. Today, the envisioned Space Launch System (SLS) offers similar size and lift capabilities that are ideally suited for a Skylab type mission. An envisioned Skylab II mission would employ the same propellant tank concept; however serve a different mission. In this case, the SLS upper stage hydrogen tank is used as a Deep Space Habitat (DSH) for NASA s planned missions to asteroids, Earth-Moon Lagrangian point and Mars.

Demandite, lunar materials and space industrialization

NASA Technical Reports Server (NTRS)

Criswell, D. R.

1977-01-01

Terrestrial industry consumes a wide range of elements in producing the outputs which support and make industrial societies possible. 'Demandite' is a conceptual or synthetic molecule which is composed of the weight fractions of the major elements consumed by industry. Demandite needed for mature industrial activities in space will differ from the terrestrial composition because solar energy must replace hydrocarbon-energy, lunar and asteroidal bulk compositions are different from mineral deposits on the earth, and the major bulk processing in space will be the creation of radiation shielding for human habitats to provide real estate in space complete with water, atmosphere and life-stock elements. Demandite cost may be dominated by earth to deep space transport cost of minor elemental constituents depleted in the lunar soils unless careful attention is given to substitution of materials, searches of the moon (polar regions) and asteroids for the depleted elements, and continuing lowering of earth to deep space transport costs.

Detection of a possible superluminous supernova in the epoch of reionization

NASA Astrophysics Data System (ADS)

Mould, Jeremy; Abbott, Tim; Cooke, Jeff; Curtin, Chris; Katsiani, Antonios; Koekemoer, Anton; Tescari, Edoardo; Uddin, Syed; Wang, Lifan; Wyithe, Stuaet

2017-04-01

An interesting transient has been detected in one of our three Dark Energy Camera deep fields. Observations of these deep fields take advantage of the high red sensitivity of DECam on the Cerro Tololo Interamerican Observatory Blanco telescope. The survey includes the Y band with rest wavelength 1430{Å} at z = 6. Survey fields (the Prime field 0555-6130, the 16hr field 1600-75 and the SUDSS New Southern Field) are deeper in Y than other infrared surveys. They are circumpolar, allowing all night to be used efficiently, exploiting the moon tolerance of 1 micron observations to minimize conflict with the Dark Energy Survey. As an i-band dropout (meaning that the flux decrement shortward of Lyman alpha is in the i bandpass), the transient we report here is a supernova candidate with z 6, with a luminosity comparable to the brightest known current epoch superluminous supernova (i.e., 2 x 10^11 solar luminosities).

What Is Deep Vein Thrombosis?

MedlinePlus

... the blood to trigger the activity of the enzyme thrombin. Active thrombin then forms long protein strands that clump together with platelets and red blood cells to form clots. Read less Risk Factors Risk factors for VTE include a history of a previous VTE event; surgery; medical conditions ...

Landslides triggered by the winter 1996-97 storms in the Puget Lowland, Washington

USGS Publications Warehouse

Baum, Rex L.; Chleborad, Alan F.; Schuster, Robert L.

1998-01-01

Snowmelt and rainfall events triggered many landslides and debris flows in the Seattle, Washington, area during late December 1996 and January and March 1997. Landslides caused the deaths of at least four people, millions of dollars in damage to public and private property, lost revenues, traffic diversions, and other direct and indirect losses. Although shallow slides and debris flows were the most common slope failures, many deep-seated slides also occurred. Comparing maps that show distribution of historic landslides with reports of landslides compiled by city and county governments for the winter of 1996-97 and our field reconnaissance of recent landslide deposits and scars indicates that many bluffs and steep hillsides are sites of recurring failures. Investigation of the 1996-97 landslides indicates that houses and other structures built downslope from steep bluffs are in particular danger of impact by debris flows, while those on the benches, slopes, or rim of bluffs are subject to severe damage by deep slides.

Enabling Planetary Geodesy With the Deep Space Network

NASA Astrophysics Data System (ADS)

Park, R. S.; Asmar, S. W.; Armstrong, J. W.; Buccino, D.; Folkner, W. M.; Iess, L.; Konopliv, A. S.; Lazio, J.

2015-12-01

For five decades of planetary exploration, missions have carried out Radio Science experiments that led to numerous discoveries in planetary geodesy. The interior structures of many planets, large moons, asteroids and comet nuclei have been modeled based on their gravitational fields and dynamical parameters derived from precision Doppler and range measurements, often called radio metrics. Advanced instrumentation has resulted in the high level of data quality that enabled scientific breakthroughs. This instrumentation scheme, however, is distributed between elements on the spacecraft and others at the stations of the Deep Space Network (DSN), making the DSN a world-class science instrument. The design and performance of the DSN stations directly determines the quality of the science observables and radio link-based planetary geodesy observations are established by methodologies and capabilities of the DSN. In this paper, we summarize major recent discoveries in planetary geodesy at the rocky planets and the Moon, Saturnian and Jovian satellites, Phobos, and Vesta; experiments and analysis in progress at Ceres and Pluto; upcoming experiments at Jupiter, Saturn and Mars (InSight), and the long-term outlook for approved future missions with geodesy objectives. The DSN's role will be described along the technical advancements in DSN transmitters, receivers, atomic clocks, and other specialized instrumentation, such as the Advanced Water Vapor Radiometer, Advanced Ranging Instrument, as well as relevant mechanical and electrical components. Advanced techniques for calibrations of known noise sources and Earth's troposphere, ionosphere, and interplanetary plasma are also presented. A typical error budget will be presented to aid future investigations in carrying out trade-off studies in the end-to-end system performance.

Rainfall characteristics associated to the triggering of fast- and slow-moving landslides - a comparison between the South French Alps and Lower Austria

NASA Astrophysics Data System (ADS)

Remaitre, Alexandre; Wallner, Stefan; Promper, Catrin; Glade, Thomas; Malet, Jean-Philippe

2013-04-01

Rainfall is worldwide a recognized trigger of landslides. Numerous studies were conducted in order to define the relationships between the precipitations and the triggering or the reactivation of landslides. Hydrological triggering of landslides can be divided in three general types: (1) development of local perched water tables in the subsoil leading to shallow slope instabilities and possible gravitational flows, (2) long-lasting rise in permanent water tables leading to more deep-seated slope instabilities, and (3) intense runoff causing channel-bed erosion and debris flows. Types (1) and (3) are usually observed during high rainfall intensities (hourly and daily rainfall) associated to heavy storms; type (2) is usually observed through increasing water content in the subsoil due to antecedent rainfalls (weekly or monthly rainfall) and/or massive snowmelt. Many investigations have been carried out to determine the amount of precipitation needed to trigger slopes failures. For rainfall-induced landslides a threshold may be define the rainfall, soil moisture or hydrological conditions that, when reached or exceeded, are likely to trigger landslides. Usually rainfall thresholds can be defined on physical process-based or conceptual models or empirical, historical and statistical bases. Nevertheless, both the large variety of landslides and to the extreme variety of climatic conditions leading to the triggering or the reactivation of a landslide lead to a regional definition of relationships between landslide occurrence and associated climatic conditions. The purpose of this case study is to analyze the relationships between the triggering of three types of landslides, debris flows, shallow landslides and deep-seated mudslides, and different patterns of rainfall in two study sites with different physiographic and climatic characteristics: the Barcelonnette basin in the South French Alps and the Waidhofen an der Ybbs area in Lower Austria. For this purpose, we exploit for the two test sites a landslide catalogue and rainfall data series to define a typology of rainfall induced-landslides for the relevant landslide types. Results from an analysis of the rainfall conditions associated to these events at different time scale (yearly, monthly, daily and hourly) show a clear distinction between these landslides. Slow-moving landslides are often associated to persistent rainstorms with low intensities during long periods causing the saturation of the soils while fast-moving landslides are usually triggered by short rainfall events with high intensities that occur in summer.

Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND).

PubMed

Livengood, T A; Chin, G; Sagdeev, R Z; Mitrofanov, I G; Boynton, W V; Evans, L G; Litvak, M L; McClanahan, T P; Sanin, A B; Starr, R D; Su, J J

2015-07-15

The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon's naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6 σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ~1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon's rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery.

Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND)

NASA Astrophysics Data System (ADS)

Livengood, T. A.; Chin, G.; Sagdeev, R. Z.; Mitrofanov, I. G.; Boynton, W. V.; Evans, L. G.; Litvak, M. L.; McClanahan, T. P.; Sanin, A. B.; Starr, R. D.; Su, J. J.

2015-07-01

The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon's naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ∼1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon's rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery.

Heat transport in the high-pressure ice mantle of large icy moons

NASA Astrophysics Data System (ADS)

Choblet, Gael; Tobie, Gabriel; Sotin, Christophe; Kalousova, Klara; Grasset, Olivier

2017-04-01

While the existence of a buried ocean sandwiched between surface ice and high-pressure (HP) polymorphs of ice emerges as the most plausible structure for the hundreds-of-kilometers thick hydrospheres within large icy moons of the Solar System (Ganymede, Callisto, Titan), little is known about the thermal structure of the deep HP ice mantle and its dynamics, possibly involving melt production and extraction. This has major implications for the thermal history of these objects as well as on the habitability of their ocean as the HP ice mantle is presumed to limit chemical transport from the rock component to the ocean. Here, we describe 3D spherical simulations of subsolidus thermal convection tailored to the specific structure of the HP ice mantle of large icy moons. Melt production is monitored and melt transport is simplified by assuming instantaneous extraction to the ocean above. The two controlling parameters for these models are the rheology of ice VI and the heat flux from the rock core. Reasonable end-members are considered for both parameters as disagreement remains on the former (especially the pressure effect on viscosity) and as the latter is expected to vary significantly during the moon's history. We show that the heat power produced by radioactive decay within the rock core is mainly transported through the HP ice mantle by melt extraction to the ocean, with most of the melt produced directly above the rock/water interface. While the average temperature in the bulk of the HP ice mantle is always relatively cool when compared to the value at the interface with the rock core (˜ 5 K above the value at the surface of the HP ice mantle), maximum temperatures at all depths are close to the melting point, often leading to the interconnection of a melt path via hot convective plume conduits throughout the HP ice mantle. Overall, we predict long periods of time during these moons' history where water generated in contact with the rock core is transported to the above ocean.

Heat transport in the high-pressure ice mantle of large icy moons

NASA Astrophysics Data System (ADS)

Choblet, G.; Tobie, G.; Sotin, C.; Kalousová, K.; Grasset, O.

2017-03-01

While the existence of a buried ocean sandwiched between surface ice and high-pressure (HP) polymorphs of ice emerges as the most plausible structure for the hundreds-of-kilometers thick hydrospheres within large icy moons of the Solar System (Ganymede, Callisto, Titan), little is known about the thermal structure of the deep HP ice mantle and its dynamics, possibly involving melt production and extraction. This has major implications for the thermal history of these objects as well as on the habitability of their ocean as the HP ice mantle is presumed to limit chemical transport from the rock component to the ocean. Here, we describe 3D spherical simulations of subsolidus thermal convection tailored to the specific structure of the HP ice mantle of large icy moons. Melt production is monitored and melt transport is simplified by assuming instantaneous extraction to the ocean above. The two controlling parameters for these models are the rheology of ice VI and the heat flux from the rock core. Reasonable end-members are considered for both parameters as disagreement remains on the former (especially the pressure effect on viscosity) and as the latter is expected to vary significantly during the moon's history. We show that the heat power produced by radioactive decay within the rock core is mainly transported through the HP ice mantle by melt extraction to the ocean, with most of the melt produced directly above the rock/water interface. While the average temperature in the bulk of the HP ice mantle is always relatively cool when compared to the value at the interface with the rock core (∼ 5 K above the value at the surface of the HP ice mantle), maximum temperatures at all depths are close to the melting point, often leading to the interconnection of a melt path via hot convective plume conduits throughout the HP ice mantle. Overall, we predict long periods of time during these moons' history where water generated in contact with the rock core is transported to the above ocean.

Libration Point Navigation Concepts Supporting Exploration Vision

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Folta, David C.; Moreau, Michael C.; Gramling, Cheryl J.

2004-01-01

Farquhar described several libration point navigation concepts that would appear to support NASA s current exploration vision. One concept is a Lunar Relay Satellite operating in the vicinity of Earth-Moon L2, providing Earth-to-lunar far-side and long- range surface-to-surface navigation and communications capability. Reference [ 1] lists several advantages of such a system in comparison to a lunar orbiting relay satellite constellation. Among these are one or two vs. many satellites for coverage, simplified acquisition and tracking due to very low relative motion, much longer contact times, and simpler antenna pointing. An obvious additional advantage of such a system is that uninterrupted links to Earth avoid performing critical maneuvers "in the blind." Another concept described is the use of Earth-Moon L1 for lunar orbit rendezvous, rather than low lunar orbit as was done for Apollo. This rendezvous technique would avoid large plane change and high fuel cost associated with high latitude landing sites and long stay times. Earth-Moon L1 also offers unconstrained launch windows from the lunar surface. Farquhar claims this technique requires only slightly higher fuel cost than low lunar orbit rendezvous for short-stay equatorial landings. Farquhar also describes an Interplanetary Transportation System that would use libration points as terminals for an interplanetary shuttle. This approach would offer increased operational flexibility in terms of launch windows, rendezvous, aborts, etc. in comparison to elliptical orbit transfers. More recently, other works including Folta[3] and Howell[4] have shown that patching together unstable trajectories departing Earth-Moon libration points with stable trajectories approaching planetary libration points may also offer lower overall fuel costs than elliptical orbit transfers. Another concept Farquhar described was a Deep Space Relay at Earth-Moon IA and/or L5 that would serve as a high data rate optical navigation and communications relay satellite. The advantages in comparison to a geosynchronous relay are minimal Earth occultation, distance from large noise sources on Earth, easier pointing due to smaller relative velocity, and a large baseline for interferometry if both L4 and L5 are used.

Triggering of frequent turbidity currents in Monterey Canyon and the role of antecedent conditioning

NASA Astrophysics Data System (ADS)

Clare, M. A.; Rosenberger, K. J.; Talling, P.; Barry, J.; Maier, K. L.; Parsons, D. R.; Simmons, S.; Gales, J. A.; Gwiazda, R.; McGann, M.; Paull, C. K.

2017-12-01

Turbidity currents pose a hazard to seafloor infrastructure, deliver organic carbon and nutrients to deep-sea communities, and form economically important deposits. Thus, determining the tempo of turbidity current activity and whether different triggers result in different flow modes is important. Identification of specific triggers is challenging, however, because most studies of turbidity currents are based on their deposits. New direct monitoring of flows and environmental conditions provides the necessary temporal constraints to identify triggering mechanisms. The Coordinated Canyon Experiment (CCE) in Monterey Canyon, offshore California is the most ambitious attempt yet to measure turbidity flows and their triggers. The CCE provides precise constraint on flow timing, initiation, and potential triggers based on measurements at 7 different instrumented moorings and 2 metocean buoys. Fifteen turbidity flows were measured in 18 months; with recorded velocities >8 m/s and run-outs of up to 50 km. Presence of live estuarine foraminifera within moored sediment traps suggests that that flows originated in water depths of <10 m, but it is unclear specifically how these flows were triggered. Turbidity currents are thought to be triggered by processes including earthquakes, river floods and storm waves. Here we analyse seismicity, local river discharge, internal tides, wave height, direction and period data. We identify no clear control of any of these individual variables on flow timing. None of the recorded earthquakes (

A preliminary regional assessment of earthquake-induced landslide susceptibility for Vrancea Seismic Region

NASA Astrophysics Data System (ADS)

Micu, Mihai; Balteanu, Dan; Ionescu, Constantin; Havenith, Hans; Radulian, Mircea; van Westen, Cees; Damen, Michiel; Jurchescu, Marta

2015-04-01

In seismically-active regions, earthquakes may trigger landslides enhancing the short-to-long term slope denudation and sediment delivery and conditioning the general landscape evolution. Co-seismic slope failures present in general a low frequency - high magnitude pattern which should be addressed accordingly by landslide hazard assessment, with respect to the generally more frequent precipitation-triggered landslides. The Vrancea Seismic Region, corresponding to the curvature sector of the Eastern Romanian Carpathians, represents the most active sub-crustal (focal depth > 50 km) earthquake province of Europe. It represents the main seismic energy source throughout Romania with significant transboundary effects recorded as far as Ukraine and Bulgaria. During the last 300 years, the region featured 14 earthquakes with M>7, among which seven events with magnitude above 7.5 and three between 7.7 and 7.9. Apart from the direct damages, the Vrancea earthquakes are also responsible for causing numerous other geohazards, such as ground fracturing, groundwater level disturbances and possible deep-seated landslide occurrences (rock slumps, rock-block slides, rock falls, rock avalanches). The older deep-seated landslides (assumed to have been) triggered by earthquakes usually affect the entire slope profile. They often formed landslide dams strongly influencing the river morphology and representing potential threats (through flash-floods) in case of lake outburst. Despite the large potential of this research issue, the correlation between the region's seismotectonic context and landslide predisposing factors has not yet been entirely understood. Presently, there is a lack of information provided by the geohazards databases of Vrancea that does not allow us to outline the seismic influence on the triggering of slope failures in this region. We only know that the morphology of numerous large, deep-seated and dormant landslides (which can possibly be reactivated in future) with head scarps near mountain tops and close to faults is similar to the one of large mass movements for which a seismic origin is proved (such as in the Tien Shan, Pamir, Longmenshan, etc.). Thus, correlations between landslide occurrence and combined seismotectonic and climatic factors are needed to support a regional multi-hazard risk assessment. The purpose of this paper is to harmonize for the first time at a regional scale the landslide predisposing factors and seismotectonic triggers and to present a first qualitative insight into the earthquake-induced landslide susceptibility for the Vrancea Seismic Region in terms of a GIS-based analysis of Newmark displacement (ND). In this way, it aims at better defining spatial and temporal distribution patterns of earthquake-triggered landslides. Arias Intensity calculation involved in the assessment considers both regional seismic hazard aspects and singular earthquake scenarios (adjusted by topography amplification factors). The known distribution of landslides mapped through digital stereographic interpretation of high-resolution aerial photos is compared with digital active fault maps and the computed ND maps to statistically outline the seismotectonic influence on slope stability in the study area. The importance of this approach resides in two main outputs. The fist one, of a fundamental nature, by providing the first regional insight into the seismic landslides triggering framework, is allowing us to understand if deep-focus earthquakes may trigger massive slope failures in an area with a relatively smooth relief (compared to the high mountain regions in Central Asia, the Himalayas), considering possible geologic and topographic site effects. The second one, more applied, will allow a better accelerometer instrumentation and monitoring of slopes and also will provide a first correlation of different levels of seismic shaking with precipitation recurrences, an important relationship within a multi-hazard risk preparedness and prevention framework.

Introduction to EGU session "Lunar Science and Exploration Towards Moon Village"

NASA Astrophysics Data System (ADS)

Foing, Bernard

2017-04-01

The EGU PS2.2 session "Lunar Science and Exploration" Towards Moon Village" will address: - Recent lunar results: geochemistry, geophysics in the context of open planetary science and exploration - Synthesis of results from SMART-1, Kaguya, Chang'e 1, 2 and 3, Chandrayaan-1, LCROSS, LADEE, Lunar Reconnaissance Orbiter and, Artemis and GRAIL - Goals and Status of missions under preparation: orbiters, Luna-Glob, Google Lunar X Prize, Luna Resurs polar lander, SLIM, Chandrayaan2, Chang'E 4 & 5, Lunar Resource Prospector, Future landers, Lunar sample return missions - Precursor missions, instruments and investigations for landers, rovers, sample return, and human cis-lunar activities and human lunar surface sorties - Preparation for International Lunar Decade: databases, instruments, missions, terrestrial field campaigns, support studies - ILEWG and Global Exploration roadmaps towards a global robotic/human Moon village - Strategic Knowledge Gaps, and key science Goals relevant to Lunar Global Exploration Lunar science and exploration are developing further with new and exciting missions being developed by China, the US, Japan, India, Russia, Korea and Europe, and with new stakeholders. The Moon Village is an open concept proposed by ESA DG with the goal of a sustainable human and robotic presence on the lunar surface as an ensemble where multiple users can carry out multiple activities. Multiple goals of the Moon Village include planetary science, life sciences, astronomy, fundamental research, resources utilisation, human spaceflight, peaceful cooperation, economical development, inspiration, training and capacity building. ESA director general has revitalized and enhanced the original concept of MoonVillage discussed in the last decade. Space exploration builds on international collaboration. COSPAR and its ILEWG International Lunar Exploration Working Group (created in 1994) have fostered collaboration between lunar missions [4-8]. A flotilla of lunar orbiters has flown in the last international lunar decade (SMART-1, Kaguya, Chang'Eal1 &2, Chandrayaan-1, LCROSS, LRO, GRAIL, LADEE). Chinese Chang'E 3 lander and Yutu rover, and upcoming 2017 other landers from 2017 (GLXP, Chang'E 4 & 5, SLIM, Luna , LRP) will constitute a Robotic Village on the Moon. A number of MoonVillage talks and/or interactive jam sessions have been conducted at International workshops and symposia 2016. Moon Village Workshops were held at ESA centres: they were held with senior experts as well as Young ESA professionals to discuss general topics and specific issues ( habitat design, technology, science and precursor missions; public and stakeholder engagement) . Many workshops were complemented with ILEWG EuroMoonMars simulation campaigns. Moon Village Workshops or Jam sessions were also conducted at international symposia or in collaboration with specific universities or institutes. The PS2.2 session will include invited and contributed talks as well as a panel discussion and interactive posters with short oral introduction. Acknowledgements We thank Prof J. Woerner (ESA DG) for energizing the concept of MoonVillage. We thank co-conveners of MoonVillage Workshops and ILEWG EuroMoonMars field campaigns in 2016 (including C. Jonglez, V.Guinet, M.Monnerie, A. Kleinschneider, A. Kapoglou, A. Kolodziejczyk, M. Harasymczuk, I. Schlacht, C. Heinicke, D. Esser, M.Grulich, T. Siruguet, H.Vos, M.Mirino, D.Sokolsky, J.Blamont) and participants to these events. We thank A.Cowley, C. Haigneré, P. Messina, G. Ortega, S.Cristoforetti, ESA colleagues involved in MoonVillage related activities. We thank colleagues from ILEWG, Young Lunar Explorers, the International Lunar Decade Group, the Moon Village Association and Moon Village Support Groups and "MoonVillagers" at large. [1] Jan Wörner, Driving #MoonVillage http://www.iafastro.org/events/iac/iac-2015/plenaryprogramme/the-moon-a-continent-and-a-gateway-for-ourfuture/ (IAC 2015, Jerusalem); [2]http://www.iafastro.org/events/iac/iac2016/globalnetworking-forum/making-the-moon-village-and-marsjourney-accessible-and-affordable-for-all/ (IAC 2016) ; [3] B. Foing et al , Highlights from Moon Village Workshop, held at ESTEC in December 2015, http://www.hou.usra.edu/meetings/lpsc2016/pdf/2719.pdf, http://www.hou.usra.edu/meetings/lpsc2016/pdf/2798.pdf [4] P. Ehrenfreund et al. "Toward a Global Space Exploration Program: A Stepping Stone Approach" (Advances in Space Research, 49, n°1, January 2012), prepared by COSPAR Panel on Exploration (PEX) [5] http://www.lpi.usra.edu/leag/GER_2011.pdf; [6] http://sci.esa.int/ilewg/47170-gluc-iceum11- beijing-2010lunar-declaration/; [7] http://www.lpi.usra.edu/meetings/leagilewg2008/ [8] http://sci.esa.int/ilewg/41506-iceum9-sorrento- 2007-lunar-declaration/ [9] National Research Council (2007), The Scientific Context for Exploration of the Moon [10] P. Ehrenfreund , B.H. Foing, A. Cellino Editors, The Moon and Near Earth Objects), Advances in Space Research, Volume 37, Issue 1, pp 1-192, 2006 [11] http://sci.esa.int/ilewg/38863-iceum8-beijing- 2006declaration/ [12] W. Huntress, D. Stetson, R. Farquhar, J. Zimmerman, B. Clark, W. O'Neil, R. Bourke& B. Foing,'The next steps in exploring deep space - A cosmic study by the IAA', Acta Astronautica, Vol 58, Issues 6-7, 2006, p302-377 [13]http://sci.esa.int/ilewg/38178-iceum7-toronto-2005-declaration/ [14] H. Balsiger et al. Eds, International Lunar Workshop, 1994 May 31-June 3, Beatenberg, Switzerland. Proceedings. Ed. European Space Agency, 1994. ESA-SP-1170 [15] R.M. Bonnet et al, 'Mission to the Moon, Europe's Priorities for Scientific Exploration and Utilisation of the Moon', European Space Agency, ESA SP-1150, June 1992 [16] http://www.iafastro.org/events/iaf-spring-meetings/spring-meetings-2016/ [17] https://www.spacesymposium.org/ [18] http://www.egu2016.eu/ http://meetingorganizer.copernicus.org/EGU2016/session/20378 [19] https://els2016.arc.nasa.gov/ [20] https://nesf2016.arc.nasa.gov/ [21] https://www.cospar-assembly.org/abstractcd/COSPAR-16/ [22] https://www.iac2016.org/, [23] http://www.hou.usra.edu/meetings/leag2016/presentations/ [24] http://newworlds2016.space/ [25] http://www.stx.ox.ac.uk/happ/events/history-moon [26] https://www.cranfield.ac.uk/events/events-2016/manufacturing-2075#

Light and lunar cycle as cues to diel migration of a sound-scattering layer

NASA Astrophysics Data System (ADS)

Benoit-Bird, Kelly J.; Au, Whitlow W. L.

2001-05-01

The Hawaiian mesopelagic boundary community is an island-associated midwater scattering layer comprised of small fishes, shrimps, and squids that undergoes diel vertical as well as horizontal migrations. It has been hypothesized that light levels are an important cue or trigger for vertical migration and presumably, horizontal migration. The migration pattern of the scattering layer was measured over complete lunar cycles while the incident light levels were recorded. Due to differences in the rise and set times of the moon and cloud cover, light and lunar cycle were not completely coupled, allowing separation of the light effects of moon phase and other cues associated with lunar cycle. Four calibrated echosounder moorings were deployed with approximately even spacing, perpendicular to the leeward coast of Oahu. Moorings were deployed for one complete lunar cycle at each of three locations, recording 10 echoes every 15 min. Light sensors measured the nocturnal light intensity at 30-s intervals. Statistical analysis revealed significant effects of both light and other lunar cycle cues. Overall, the effect size was very low considering the light transmission characteristics of the subtropical Pacific, making measurement from stationary acoustic platforms critical.

Three-Dimensional Analysis of Deep Space Network Antenna Coverage

NASA Technical Reports Server (NTRS)

Kegege, Obadiah; Fuentes, Michael; Meyer, Nicholas; Sil, Amy

2012-01-01

There is a need to understand NASA s Deep Space Network (DSN) coverage gaps and any limitations to provide redundant communication coverage for future deep space missions, especially for manned missions to Moon and Mars. The DSN antennas are required to provide continuous communication coverage for deep space flights, interplanetary missions, and deep space scientific observations. The DSN consists of ground antennas located at three sites: Goldstone in USA, Canberra in Australia, and Madrid in Spain. These locations are not separated by the exactly 120 degrees and some DSN antennas are located in the bowl-shaped mountainous terrain to shield against radiofrequency interference resulting in a coverage gap in the southern hemisphere for the current DSN architecture. To analyze the extent of this gap and other coverage limitations, simulations of the DSN architecture were performed. In addition to the physical properties of the DSN assets, the simulation incorporated communication forward link calculations and azimuth/elevation masks that constrain the effects of terrain for each DSN antenna. Analysis of the simulation data was performed to create coverage profiles with the receiver settings at a deep space altitudes ranging from 2 million to 10 million km and a spherical grid resolution of 0.25 degrees with respect to longitude and latitude. With the results of these simulations, two- and three-dimensional representations of the area without communication coverage and area with coverage were developed, showing the size and shape of the communication coverage gap projected in space. Also, the significance of this communication coverage gap is analyzed from the simulation data.

Near-infrared deep brain stimulation via upconversion nanoparticle–mediated optogenetics

NASA Astrophysics Data System (ADS)

Chen, Shuo; Weitemier, Adam Z.; Zeng, Xiao; He, Linmeng; Wang, Xiyu; Tao, Yanqiu; Huang, Arthur J. Y.; Hashimotodani, Yuki; Kano, Masanobu; Iwasaki, Hirohide; Parajuli, Laxmi Kumar; Okabe, Shigeo; Teh, Daniel B. Loong; All, Angelo H.; Tsutsui-Kimura, Iku; Tanaka, Kenji F.; Liu, Xiaogang; McHugh, Thomas J.

2018-02-01

Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecularly tailored UCNPs can serve as optogenetic actuators of transcranial NIR light to stimulate deep brain neurons. Transcranial NIR UCNP-mediated optogenetics evoked dopamine release from genetically tagged neurons in the ventral tegmental area, induced brain oscillations through activation of inhibitory neurons in the medial septum, silenced seizure by inhibition of hippocampal excitatory cells, and triggered memory recall. UCNP technology will enable less-invasive optical neuronal activity manipulation with the potential for remote therapy.

The Role of Spinel Minerals in Lunar Magma Evolution

NASA Astrophysics Data System (ADS)

Taylor, L. A.; Head, J. W.; Pieters, C. M.; Sunshine, J. M.; Staid, M.; Isaacson, P.; Petro, N. E.

2009-12-01

The Moon Mineralogy Mapper (M3), a NASA guest instrument on Chandrayaan-1, India’s first mission to the Moon, was designed to map the surface mineralogy of the Moon using reflected solar radiation at visible and near-infrared wavelengths, which contain highly diagnostic absorptions due to minerals. The M3 spectrometer has discovered several new and unexpected aspects of the geology and petrology of the Moon, some involving specific oxide phases. Spinel minerals, with the general formula, AB2O4, present clues as to the oxygen fugacity, the nature of magmatic systems, and their evolution, particularly during the early stages of crystallization. On the Moon, with its total lack of Fe3+ and minerals such as magnetite, observed spinels range between spinel, MgAl2O4; hercynite, FeAl2O4; Chromite, FeCr2O4; and ulvöspinel, Fe(FeTi)2O4. They manifest themselves in three distinctly different igneous rock types: highlands rocks of anorthosites/troctolites, gabbro-norites; mare basalts with various TiO2 contents; and basaltic pyroclastic volcanic glasses. Although spinels occur as minor minerals in the Apollo collection, unique rock types dominated by Mg-spinel (with olivine and pyroxene abundances below detection limits, assumed to be ~5%) have been identified by M3 on the Moon. Because the spinel-bearing rocks detected by M3 have no signature of a significant olivine component, they must be dominated by plagioclase and spinel. Pink Mg-spinels typically occur as a minor phase in troctolites (plagioclase + olivine), a highland rock formed after the initial Ferroan Anorthosite (FAN) crust, presumably by serial magmatism deep within the crust, with intrusion upward. FANs were formed by floatation of plagioclase in the lunar magma ocean (LMO), whereas spinels would sink due to their much higher density. Thus, a plagioclase-rich rock type with a strong Mg-spinel spectral signature would have to be part of later highland intrusives. The excess Mg-spinel could be the product of crystal settling in an anorthositic magma chamber, much like in anorthositic layered intrusives on Earth. On the Moon, this would be a cumulate spinel anorthosite, never before seen in remote sensing or in the lunar sample collection. Virtually all types of mare basalt melts have chromite at or near the liquidus, closely associated with olivine or low-Ca pyroxene. During crystallization, the chromite becomes more Ti-rich, typically with nearly continuous solid-solution zonation outward to ulvöspinel. Pyroclastic orange/black glass on the Moon typically contains dendritic crystallites of ilmenite and olivine, a product of the rich-TiO2 content of the fire-fountain melt. However, other pyroclastic melt compositions, with high-Cr and low-Ti contents, have chromite on the liquidus, which could result in dendrites of chromite and olivine in the volcanic glass. Here again, M3 is seeing spinel-dominated materials, this time in close association with pyroclastic deposits.

THE POSSIBLE MOON OF KEPLER-90g IS A FALSE POSITIVE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kipping, D. M.; Torres, G.; Buchhave, L. A.

2015-01-20

The discovery of an exomoon would provide deep insights into planet formation and the habitability of planetary systems, with transiting examples being particularly sought after. Of the hundreds of Kepler planets now discovered, the seven-planet system Kepler-90 is unusual for exhibiting an unidentified transit-like signal in close proximity to one of the transits of the long-period gas-giant Kepler-90g, as noted by Cabrera et al. As part of the ''Hunt for Exomoons with Kepler'' project, we investigate this possible exomoon signal and find it passes all conventional photometric, dynamical, and centroid diagnostic tests. However, pixel-level light curves indicate that the moon-like signalmore » occurs on nearly all of the target's pixels, which we confirm using a novel way of examining pixel-level data which we dub the ''transit centroid''. This test reveals that the possible exomoon to Kepler-90g is likely a false positive, perhaps due to a cosmic ray induced sudden pixel sensitivity dropout. This work highlights the extreme care required for seeking non-periodic low-amplitude transit signals, such as exomoons.« less

Experiences in managing the Prometheus Project

NASA Technical Reports Server (NTRS)

Lehman, David H.; Clark, Karla B.; Cook, Beverly A.; Gavit, Sarah A.; Kayali, Sammy A.; McKinney, John C.; Milkovich, David C.; Reh, Kim R.; Taylor, Randall L.; Casani, John R.

2006-01-01

Congress authorized NASA?s Prometheus Project in February 2003, with the first Prometheus mission slated to explore the icy moons of Jupiter. The Project had two major objectives: (1) to develop a nuclear reactor that would provide unprecedented levels of power and show that it could be processed safely and operated reliably in space for long-duration, deep-space exploration and (2) to explore the three icy moons of Jupiter - Callisto, Ganymede, and Europa - and return science data that would meet the scientific goals as set forth in the Decadal Survey Report of the National Academy of Sciences. Early in Project planning, it was determined that the development of the Prometheus nuclear powered Spaceship would be complex and require the intellectual knowledge residing at numerous organizations across the country. In addition, because of the complex nature of the Project and the multiple partners, approaches beyond those successfully used to manage a typical JPL project would be needed. This paper1 will describe the key experiences in managing Prometheus that should prove useful for future projects of similar scope and magnitude

The Thermal Hogan - A Means of Surviving the Lunar Night

NASA Technical Reports Server (NTRS)

Fruitwala, Neelay; Ungar, Eugene; Cornwell, John

2013-01-01

document describes the Thermal Hogan, a new shelter concept that would be used on the Moon to moderate the extreme nighttime temperatures, allowing survival of equipment with minimal heater power. It is lightweight, has few mechanical parts, and would be relatively easy to deploy on the Moon. The Lunar Hogan has two parts: an insulated shelter and a thermal mass. The shelter is constructed of multilayer insulation (MLI) draped over a structural framework. Entry and egress are accomplished either by raising the structure or via a door constructed of the same MLI material as the shelter. The thermal mass can be manufactured from locally available materials, either by piling substantially sized rocks to a depth of 0.25 meter, or by filling a 0.25-meter-deep conductive honeycomb-like structure with lunar dust. For ease of transport, the structural framework and honeycomb can be collapsible. The door can be opened by pushing on it in either direction. Gravity would cause it to close and it could be sealed via magnetic strips on the doorframe.

Materials Requirements for Advanced Propulsion Systems

NASA Technical Reports Server (NTRS)

Whitaker, Ann F.; Cook, Mary Beth; Clinton, R. G., Jr.

2005-01-01

NASA's mission to "reach the Moon and Mars" will be obtained only if research begins now to develop materials with expanded capabilities to reduce mass, cost and risk to the program. Current materials cannot function satisfactorily in the deep space environments and do not meet the requirements of long term space propulsion concepts for manned missions. Directed research is needed to better understand materials behavior for optimizing their processing. This research, generating a deeper understanding of material behavior, can lead to enhanced implementation of materials for future exploration vehicles. materials providing new approaches for manufacture and new options for In response to this need for more robust materials, NASA's Exploration Systems Mission Directorate (ESMD) has established a strategic research initiative dedicated to materials development supporting NASA's space propulsion needs. The Advanced Materials for Exploration (AME) element directs basic and applied research to understand material behavior and develop improved materials allowing propulsion systems to operate beyond their current limitations. This paper will discuss the approach used to direct the path of strategic research for advanced materials to ensure that the research is indeed supportive of NASA's future missions to the moon, Mars, and beyond.

Autonomous real-time detection of plumes and jets from moons and comets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagstaff, Kiri L.; Thompson, David R.; Bue, Brian D.

2014-10-10

Dynamic activity on the surface of distant moons, asteroids, and comets can manifest as jets or plumes. These phenomena provide information about the interior of the bodies and the forces (gravitation, radiation, thermal) they experience. Fast detection and follow-up study is imperative since the phenomena may be time-varying and because the observing window may be limited (e.g., during a flyby). We have developed an advanced method for real-time detection of plumes and jets using onboard analysis of the data as it is collected. In contrast to prior work, our technique is not restricted to plume detection from spherical bodies, makingmore » it relevant for irregularly shaped bodies such as comets. Further, our study analyzes raw data, the form in which it is available on board the spacecraft, rather than fully processed image products. In summary, we contribute a vital assessment of a technique that can be used on board tomorrow's deep space missions to detect, and respond quickly to, new occurrences of plumes and jets.« less

Emblem of the Apollo 17 lunar landing mission

NASA Technical Reports Server (NTRS)

1972-01-01

This is the Official emblem of the Apollo 17 lunar landing mission which will be flown by Astronauts Eugene A. Cernan, Ronald E. Evans and Harrison H. Schmitt. The insignia is dominated by the image of Apollo, the Greek sun god. Suspended in space behind the head of Apollo is an American eagle of contemporary design, the red bars of the eagle's wing represent the bars in the U.S. flag; the three white stars symbolize the three astronaut crewmen. The background is deep blue space and within it are the Moon, the planet Saturn and a spiral galaxy or nebula. The Moon is partially overlaid by the eagle's wing suggesting that this is a celestial body that man has visited and in that sense conquered. The thrust of the eagle and the gaze of Apollo to the right and toward Saturn and the galaxy is meant to imply that man's goals in space will someday include the planets and perhaps the stars. The colors of the emblem are red, white and blue, the colors of our flag; with the addition of gold, to

Lunar cycles in diel prey migrations exert a stronger effect on the diving of juveniles than adult Galápagos fur seals.

PubMed Central

Horning, M; Trillmich, F

1999-01-01

In our study of the development of diving in Galápagos fur seals, we analysed changes in diving activity and body mass trends over the lunar cycle. Based on previously observed lunar cycles in colony attendance patterns, we hypothesized a greater impact of prey migrations of deep scattering layer organisms on younger fur seals. Using electronic dive recorders, we determined that seals dived less and deeper on moonlit nights than at new moon, and incurred body mass losses. These changes in foraging over the lunar cycle correlate with the suppression of the vertical migration of prey by lunar light. All effects were more pronounced in juveniles than adult females, with greater relative mass loss during full moon, which must (i) negatively affect long-term juvenile growth rates, (ii) lengthen periods of maternal dependence, and (iii) contribute to the lowest reproductive rate reported for seals. This underlines the importance of studying ontogeny in order to understand life histories, and for determining the susceptibility of animal populations to fluctuations in food availability. PMID:10406130

DISCOVERY OF A MAKEMAKEAN MOON

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, Alex H.; Buie, Marc W.; Grundy, Will M.

We describe the discovery of a satellite in orbit about the dwarf planet (136472) Makemake. This satellite, provisionally designated S/2015 (136472) 1, was detected in imaging data collected with the Hubble Space Telescope ’s Wide Field Camera 3 on UTC 2015 April 27 at 7.80 ± 0.04 mag fainter than Makemake and at a separation of 0.″57. It likely evaded detection in previous satellite searches due to a nearly edge-on orbital configuration, placing it deep within the glare of Makemake during a substantial fraction of its orbital period. This configuration would place Makemake and its satellite near a mutual eventmore » season. Insufficient orbital motion was detected to make a detailed characterization of its orbital properties, prohibiting a measurement of the system mass with the discovery data alone. Preliminary analysis indicates that if the orbit is circular, its orbital period must be longer than 12.4 days and must have a semimajor axis ≳21,000 km. We find that the properties of Makemake’s moon suggest that the majority of the dark material detected in the system by thermal observations may not reside on the surface of Makemake, but may instead be attributable to S/2015 (136472) 1 having a uniform dark surface. This “dark moon hypothesis” can be directly tested with future James Webb Space Telescope observations. We discuss the implications of this discovery for the spin state, figure, and thermal properties of Makemake and the apparent ubiquity of trans-Neptunian dwarf planet satellites.« less

Scientific Objectives of China Chang E 4 CE-4 Lunar Far-side Exploration Mission

NASA Astrophysics Data System (ADS)

Zhang, Hongbo; Zeng, Xingguo; Chen, Wangli

2017-10-01

China has achieved great success in the recently CE-1~CE-3 lunar missions, and in the year of 2018, China Lunar Exploration Program (CLEP) is going to launch the CE-4 mission. CE-4 satellite is the backup satellite of CE-3, so that it also consists of a Lander and a Rover. However, CE-4 is the first mission designed to detect the far side of the Moon in human lunar exploration history. So the biggest difference between CE-4 and CE-3 is that it will be equipped with a relay satellite in Earth-Moon-L2 Point for Earth-Moon Communication. And the scientific payloads carried on the Lander and Rover will also be different. It has been announced by the Chinese government that CE-4 mission will be equipped with some new international cooperated scientific payloads, such as the Low Frequency Radio Detector from Holland, Lunar Neutron and Radiation Dose Detector from Germany, Neutral Atom Detector from Sweden, and Lunar Miniature Optical Imaging Sounder from Saudi Arabia. The main scientific objective of CE-4 is to provide scientific data for lunar far side research, including: 1)general spatial environmental study of lunar far side；2)general research on the surface, shallow layer and deep layer of lunar far side；3)detection of low frequency radio on lunar far side using Low Frequency Radio Detector, which would be the first time of using such frequency band in lunar exploration history .

Discovery of a Makemakean Moon

NASA Technical Reports Server (NTRS)

Parker, Alex H.; Buie, Marc W.; Grundy, Will M.; Noll, Keith S.

2016-01-01

We describe the discovery of a satellite in orbit about the dwarf planet (136472) Makemake. This satellite, provisionally designated S/2015 (136472) 1, was detected in imaging data collected with the Hubble Space Telescope's Wide Field Camera 3 on UTC 2015 April 27 at 7.80 +/- 0.04 mag fainter than Makemake and at a separation of 0farcs57. It likely evaded detection in previous satellite searches due to a nearly edge-on orbital configuration, placing it deep within the glare of Makemake during a substantial fraction of its orbital period. This configuration would place Makemake and its satellite near a mutual event season. Insufficient orbital motion was detected to make a detailed characterization of its orbital properties, prohibiting a measurement of the system mass with the discovery data alone. Preliminary analysis indicates that if the orbit is circular, its orbital period must be longer than 12.4 days and must have a semimajor axis > or approx. = 21,000 km. We find that the properties of Makemake's moon suggest that the majority of the dark material detected in the system by thermal observations may not reside on the surface of Makemake, but may instead be attributable to S/2015 (136472) 1 having a uniform dark surface. This dark moon hypothesis can be directly tested with future James Webb Space Telescope observations. We discuss the implications of this discovery for the spin state, figure, and thermal properties of Makemake and the apparent ubiquity of trans-Neptunian dwarf planet satellites.

Modeling and Testing of Non-Nuclear, Highpower Simulated Nuclear Thermal Rocket Reactor Elements

NASA Technical Reports Server (NTRS)

Kirk, Daniel R.

2005-01-01

When the President offered his new vision for space exploration in January of 2004, he said, "Our third goal is to return to the moon by 2020, as the launching point for missions beyond," and, "With the experience and knowledge gained on the moon, we will then be ready to take the next steps of space exploration: human missions to Mars and to worlds beyond." A human mission to Mars implies the need to move large payloads as rapidly as possible, in an efficient and cost-effective manner. Furthermore, with the scientific advancements possible with Project Prometheus and its Jupiter Icy Moons Orbiter (JIMO), (these use electric propulsion), there is a renewed interest in deep space exploration propulsion systems. According to many mission analyses, nuclear thermal propulsion (NTP), with its relatively high thrust and high specific impulse, is a serious candidate for such missions. Nuclear rockets utilize fission energy to heat a reactor core to very high temperatures. Hydrogen gas flowing through the core then becomes superheated and exits the engine at very high exhaust velocities. The combination of temperature and low molecular weight results in an engine with specific impulses above 900 seconds. This is almost twice the performance of the LOX/LH2 space shuttle engines, and the impact of this performance would be to reduce the trip time of a manned Mars mission from the 2.5 years, possible with chemical engines, to about 12-14 months.

Life Support for Deep Space and Mars

NASA Technical Reports Server (NTRS)

Jones, Harry W.; Hodgson, Edward W.; Kliss, Mark H.

2014-01-01

How should life support for deep space be developed? The International Space Station (ISS) life support system is the operational result of many decades of research and development. Long duration deep space missions such as Mars have been expected to use matured and upgraded versions of ISS life support. Deep space life support must use the knowledge base incorporated in ISS but it must also meet much more difficult requirements. The primary new requirement is that life support in deep space must be considerably more reliable than on ISS or anywhere in the Earth-Moon system, where emergency resupply and a quick return are possible. Due to the great distance from Earth and the long duration of deep space missions, if life support systems fail, the traditional approaches for emergency supply of oxygen and water, emergency supply of parts, and crew return to Earth or escape to a safe haven are likely infeasible. The Orbital Replacement Unit (ORU) maintenance approach used by ISS is unsuitable for deep space with ORU's as large and complex as those originally provided in ISS designs because it minimizes opportunities for commonality of spares, requires replacement of many functional parts with each failure, and results in substantial launch mass and volume penalties. It has become impractical even for ISS after the shuttle era, resulting in the need for ad hoc repair activity at lower assembly levels with consequent crew time penalties and extended repair timelines. Less complex, more robust technical approaches may be needed to meet the difficult deep space requirements for reliability, maintainability, and reparability. Developing an entirely new life support system would neglect what has been achieved. The suggested approach is use the ISS life support technologies as a platform to build on and to continue to improve ISS subsystems while also developing new subsystems where needed to meet deep space requirements.

Numerical investigation of the triggering mechanisms of the Piz Dora sackung system (Val Mustair, Switzerland)

NASA Astrophysics Data System (ADS)

Riva, Federico; Agliardi, Federico; Crosta, Giovanni B.; Zanchi, Andrea

2015-04-01

Deep-Seated Gravitational Slope Deformations (DSGSD) are widespread phenomena in alpine environments, where they affect entire high-relief valley flanks involving huge rock volumes. Slope scale inherited structures related to ductile and brittle tectonic deformation can control the onset and development of DSGSD and the localization of strain in deep gravitational shear zones. Slope unloading, rock mass damage and hydrological perturbations related to deglaciation are considered important triggers of these phenomena in formerly glaciated areas. Furthermore, earthquake shaking and the long-term effects of seismicity in active tectonic areas might provide an additional triggering component. Nevertheless, the role played by these different processes and their interplay is not obvious, especially in geological context less typically favourable to DSGSD and in low-magnitude seismicity settings as the axial European Alps. We analysed the Piz Dora sackung system (Val Mustair, Switzerland), which affects conglomerates, meta-conglomerates and phyllites of the Austroalpine S-Charl nappe, involved in a slope-scale, WNW trending closed anticline fold. The area is actively uplifting, seismically active (maximum Mw>5) and experienced extensive glaciation during the LGM. The slope is affected by sharp gravitational morphostructures associated to the deep-seated sliding of 1.85 km3 of rock along a basal shear zone up to 300 m deep (Agliardi et al., 2014; Barbarano et al., 2015). We investigated the controlling role of inherited tectonic features and the relative influence of different candidate triggering processes (post-glacial debuttressing, related changes in slope hydrology, seismicity) through a series of 2D Distinct Element (DEM) numerical models set up using the code UDEC (ItascaTM). Based on field structural and geomechanical data, we discretized the slope into an ensemble of discontinuum domains, accounting for the slope-scale folded structure and characterised by unique combinations of rock mass properties and persistent brittle structural patterns related to folding or regional stress fields. We analysed the processes leading to DSGSD onset and evolution by testing combinations of: a) rock mass constitutive models; b) in situ stress fields; c) hydro-mechanical coupling; d) dynamic loadings. DEM results, validated using field evidence and discussed against the results of continuum-based Finite-Element models (Agliardi et al., 2014; Barbarano et al., 2015), suggest that DSGSD failure mechanisms are constrained by fold-related brittle structures, and stress and hydrologic conditioning of deglaciation were key triggers modulated by active tectonic processes. References: - Agliardi F., Barbarano M., Crosta G.B., Riva F. & Zanchi A. (2014). Inherited and active tectonic controls on the Piz Dora sackung system (Val Mustair). In 3rd Slope Tectonic Conference proceedings, NGU Report 2014.030. - Barbarano M., Agliardi F., Crosta G. B., & Zanchi A. (2015). Inherited and Active Tectonic Controls on the Piz Dora DSGSD (Val Müstair, Switzerland). In Engineering Geology for Society and Territory-Volume 2 (pp. 605-608). Springer International Publishing.

Disengaging from Conflict Cycles

ERIC Educational Resources Information Center

Long, Nicholas J.

2014-01-01

Youth in pain often show self-defeating and destructive patterns of behavior which should be seen as calls for help and positive support. Instead, deep-seated brain programs and cultural beliefs about discipline can trigger angry or avoidant behavior by adults who deal with these young people. This brief introduction to the Conflict Cycle…

Concept Maps as Cognitive Visualizations of Writing Assignments

ERIC Educational Resources Information Center

Villalon, Jorge; Calvo, Rafael A.

2011-01-01

Writing assignments are ubiquitous in higher education. Writing develops not only communication skills, but also higher-level cognitive processes that facilitate deep learning. Cognitive visualizations, such as concept maps, can also be used as part of learning activities including as a form of scaffolding, or to trigger reflection by making…

Overview of Mission Design for NASA Asteroid Redirect Robotic Mission Concept

NASA Technical Reports Server (NTRS)

Strange, Nathan; Landau, Damon; McElrath, Timothy; Lantoine, Gregory; Lam, Try; McGuire, Melissa; Burke, Laura; Martini, Michael; Dankanich, John

2013-01-01

Part of NASA's new asteroid initiative would be a robotic mission to capture a roughly four to ten meter asteroid and redirect its orbit to place it in translunar space. Once in a stable storage orbit at the Moon, astronauts would then visit the asteroid for science investigations, to test in space resource extraction, and to develop experience with human deep space missions. This paper discusses the mission design techniques that would enable the redirection of a 100-1000 metric ton asteroid into lunar orbit with a 40-50 kW Solar Electric Propulsion (SEP) system.

Designing Interfaces for Astronaut Autonomy in Space

NASA Technical Reports Server (NTRS)

Hillenius, Steve

2015-01-01

As we move towards human deep space missions, astronauts will no longer be able to say, Houston, we have a problem. The restricted contact with mission control because of the incredible distance from Earth will require astronauts to make autonomous decisions. How will astronauts take on the roles of mission control? This is an area of active research that has far reaching implications for the future of distant spaceflight. Come to this talk to hear how we are using design and user research to come up with innovative solutions for astronauts to effectively explore the Moon, Mars, and beyond.

Telerobotics for Human Exploration: Enhancing Crew Capabilities in Deep Space

NASA Technical Reports Server (NTRS)

Fong, Terrence

2013-01-01

Future space missions in Earth orbit, to the Moon, and to other distant destinations offer many new opportunities for exploration. But, astronaut time will always be limited and some work will not be feasible or efficient for humans to perform manually. Telerobots, however, can complement human explorers, performing work under remote control from Earth, orbit or nearby habitats. A central challenge, therefore, is to understand how humans and remotely operated robots can be jointly employed to maximize mission performance and success. This presentation provides an overview of the key issues with using telerobots for human exploration.

Lunar base as a precursor to Mars exploration and settlement

NASA Technical Reports Server (NTRS)

Mendell, Wendell W.

1991-01-01

A well planned program of human exploration of the moon is suggested which would provide a base for increasing human capabilities and experience to levels required for Mars exploration. A strategy intended for immediate Mars exploration and settlement is considered to incur serious programmatic risks from current lack of knowledge on human performance on long-duration deep space missions and lack of experience in designing human space systems. The lunar program provides an opportunity to build up space capability in an evolutionary way and to broaden the participation of the educational system in the space exploration.

After 400 years, Some of Us Still Get it Wrong: Science Errors on TV (A Personal Experience)

NASA Astrophysics Data System (ADS)

Comins, Neil

2009-10-01

Students harbor misconceptions (deep-seated incorrect beliefs) about our astronomical environment. While some of these beliefs have their origins in faulty reasoning, many others come from external sources, including from teachers and even professional scientists believing and sharing misconceptions, and from media sources. I will relate a horror story of how scientists on a TV show about the Moon in which I appeared presented incorrect information and how the producers also manipulated the science presented by the narrator to provide incorrect information that viewers are likely to incorporate into their own belief systems.

Proof of principal for staircase auger chip removal theory

NASA Technical Reports Server (NTRS)

Barron, Jeffrey B.; Brewer, Steve; Kerns, Kenneth; Moody, Kyle; Rossi, Richard A.

1987-01-01

A proof of principal design of the staircase auger theory is provided for lunar drilling. The drill is designed to drill holes 30 meters deep and 0.1 meters in diameter. The action of the auger is 0.01 meter strokes at a varying number of strokes per second. A detailed analysis of the interaction of the auger and particle was done to optimize the parameters of the auger. This optimum design will allow for proper heat removal and reasonable drilling time. The drill bit is designed to scoop the particles into the auger while efficiently cutting through the moon's surface.

Selected highlights from the Extreme Ultraviolet Explorer

NASA Technical Reports Server (NTRS)

Bowyer, S.; Malina, R. F.

1995-01-01

We present a few scientific highlights from the Extreme Ultraviolet Explorer (EUVE) all-sky and deep surveys, from the EUVE Righ Angle Program, and from the EUVE Guest Observer Program. The First EUVE Source Catalog includes 410 extreme ultraviolet (EUV) sources detected in the initial processing of the EUVE all-sky data. A program of optical identification indicates that counterparts include cool star coronae, flare stars, hot white dwarfs, central stars of planetary nebulae, B star photospheres and winds, an X-ray binary, extragalactic objects (active galactic nuclei, BL Lacertae), solar system objects (Moon, Mars, Io,), supernova remnants, and two novae.

The 2016 Mw5.1 Fairview, Oklahoma earthquakes: Evidence for long-range poroelastic triggering at >40 km from fluid disposal wells

DOE PAGES

Goebel, T. H. W.; Weingarten, M.; Chen, X.; ...

2017-05-30

Wastewater disposal in the central U.S. is likely responsible for an unprecedented surge in earthquake activity. Much of this activity is thought to be driven by induced pore pressure changes and slip on pre-stressed faults, which requires a hydraulic connection between faults and injection wells. However, direct pressure effects and hydraulic connectivity are questionable for earthquakes located at large distances and depths from the injectors. Here, we examine triggering mechanisms of induced earthquakes, which occurred at more than 40 km from wastewater disposal wells in the greater Fairview region, northwest Oklahoma, employing numerical and semi-analytical poroelastic models. The region exhibitedmore » few earthquakes before 2013, when background seismicity started to accelerate rapidly, culminating in the Mw5.1 Fairview earthquake in February 2016. Injection rates in the ~2–2.5km deep Arbuckle formation started to increase rapidly in 2012, about two years before the start of seismicity-increase. Most of the injection activity was concentrated toward the northeast of the study region, generating a relatively cohesive zone of pressure perturbations between 0.1 and 1MPa. Much of the near-injection seismicity was likely triggered by pressure effects and fault-assisted pressure diffusion to seismogenic depth. Outside of the high-pressure zone, we observed two remarkably detached, linear seismicity clusters, which occurred at 20 to 50 km distance from the initial seismicity and 10 to 40 km from the nearest, high-rate injector. Semi-analytical models reveal that poroelastically-induced Coulomb-stress-changes surpass pore pressure changes at these distances, providing a plausible triggering mechanism in the far-field of injection wells. These results indicate that both pore-pressures and poroelastic stresses can play a significant role in triggering deep and distant earthquakes by fluid injection and should be considered for seismic hazard assessment beyond the targeted reservoir.« less

The 2016 Mw5.1 Fairview, Oklahoma earthquakes: Evidence for long-range poroelastic triggering at >40 km from fluid disposal wells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goebel, T. H. W.; Weingarten, M.; Chen, X.

Wastewater disposal in the central U.S. is likely responsible for an unprecedented surge in earthquake activity. Much of this activity is thought to be driven by induced pore pressure changes and slip on pre-stressed faults, which requires a hydraulic connection between faults and injection wells. However, direct pressure effects and hydraulic connectivity are questionable for earthquakes located at large distances and depths from the injectors. Here, we examine triggering mechanisms of induced earthquakes, which occurred at more than 40 km from wastewater disposal wells in the greater Fairview region, northwest Oklahoma, employing numerical and semi-analytical poroelastic models. The region exhibitedmore » few earthquakes before 2013, when background seismicity started to accelerate rapidly, culminating in the Mw5.1 Fairview earthquake in February 2016. Injection rates in the ~2–2.5km deep Arbuckle formation started to increase rapidly in 2012, about two years before the start of seismicity-increase. Most of the injection activity was concentrated toward the northeast of the study region, generating a relatively cohesive zone of pressure perturbations between 0.1 and 1MPa. Much of the near-injection seismicity was likely triggered by pressure effects and fault-assisted pressure diffusion to seismogenic depth. Outside of the high-pressure zone, we observed two remarkably detached, linear seismicity clusters, which occurred at 20 to 50 km distance from the initial seismicity and 10 to 40 km from the nearest, high-rate injector. Semi-analytical models reveal that poroelastically-induced Coulomb-stress-changes surpass pore pressure changes at these distances, providing a plausible triggering mechanism in the far-field of injection wells. These results indicate that both pore-pressures and poroelastic stresses can play a significant role in triggering deep and distant earthquakes by fluid injection and should be considered for seismic hazard assessment beyond the targeted reservoir.« less

The 2016 Mw5.1 Fairview, Oklahoma earthquakes: Evidence for long-range poroelastic triggering at >40 km from fluid disposal wells

NASA Astrophysics Data System (ADS)

Goebel, T. H. W.; Weingarten, M.; Chen, X.; Haffener, J.; Brodsky, E. E.

2017-08-01

Wastewater disposal in the central U.S. is likely responsible for an unprecedented surge in earthquake activity. Much of this activity is thought to be driven by induced pore pressure changes and slip on pre-stressed faults, which requires a hydraulic connection between faults and injection wells. However, direct pressure effects and hydraulic connectivity are questionable for earthquakes located at large distances and depths from the injectors. Here, we examine triggering mechanisms of induced earthquakes, which occurred at more than 40 km from wastewater disposal wells in the greater Fairview region, northwest Oklahoma, employing numerical and semi-analytical poroelastic models. The region exhibited few earthquakes before 2013, when background seismicity started to accelerate rapidly, culminating in the Mw5.1 Fairview earthquake in February 2016. Injection rates in the ∼2-2.5 km deep Arbuckle formation started to increase rapidly in 2012, about two years before the start of seismicity-increase. Most of the injection activity was concentrated toward the northeast of the study region, generating a relatively cohesive zone of pressure perturbations between 0.1 and 1 MPa. Much of the near-injection seismicity was likely triggered by pressure effects and fault-assisted pressure diffusion to seismogenic depth. Outside of the high-pressure zone, we observed two remarkably detached, linear seismicity clusters, which occurred at 20 to 50 km distance from the initial seismicity and 10 to 40 km from the nearest, high-rate injector. Semi-analytical models reveal that poroelastically-induced Coulomb-stress-changes surpass pore pressure changes at these distances, providing a plausible triggering mechanism in the far-field of injection wells. These results indicate that both pore-pressures and poroelastic stresses can play a significant role in triggering deep and distant earthquakes by fluid injection and should be considered for seismic hazard assessment beyond the targeted reservoir.

Quivering on the brink: Common observations of turbidity current frequency and triggering in disparate settings

NASA Astrophysics Data System (ADS)

Clare, M. A.; Rosenberger, K. J.; Parsons, D. R.; Gales, J. A.; Gwiazda, R.; Paull, C. K.; Talling, P.; Cartigny, M.; Azpiroz, M.; Pope, E.; Hizzett, J. L.; Hughes Clarke, J. E.

2017-12-01

Turbidity currents pose a hazard to seafloor infrastructure, convey sediment to the deep sea, and provide nutrients to benthic communities. Despite their importance, we still know little about specifically how and when such powerful long run-out flows are triggered, and how strongly different trigger mechanisms control flow behaviour. New advances in direct monitoring now allow us to precisely constrain turbidity current frequency and test the efficiency of previously hypothesised triggering mechanisms. Here, we document the timing of sub-annual turbidity currents based on direct measurements using Acoustic Doppler Current Profilers at four different sites. Two sites are located at offshore fjord-head deltas in British Columbia (Squamish delta & Bute Inlet), which are fed by meltwater in spring and summer. The third is the deep-water Congo Canyon, which is located offshore Angola, and is fed by the second largest river in the world. Fourth is the Monterey Canyon, offshore California, which does not have a direct link to a river and is instead fed by littoral drift. Despite the differences in scale and setting, all of the sites show similar trends in turbidity current frequency. The first commonality is that flow timing is typically delayed (hours to weeks) following periods of rapid sediment discharge, rather than immediately coincident with them. The second commonality is that flows are rare (typically they do not occur at all) for at least half of the year in each of the sites. Instead, flows are clustered within a specific time window. We underline the importance of preconditioning prior to, and during that time window and propose that an environmental threshold must be exceeded in order to "switch on" these systems. This threshold primarily relates to magnitude of sediment delivery at the head of the channel or canyon. Once that threshold is surpassed, then systems are primed for action, quivering on the brink, allowing even small external perturbations to trigger flows.

Tectonic tremor and LFEs on a reverse fault in Taiwan

DOE PAGES

Aguiar, Ana C.; Chao, Kevin; Beroza, Gregory C.

2017-06-16

In this paper, we compare low-frequency earthquakes (LFEs) from triggered and ambient tremor under the southern Central Range, Taiwan. We apply the PageRank algorithm used by Aguiar and Beroza (2014) that exploits the repetitive nature of the LFEs to find repeating LFEs in both ambient and triggered tremor. We use these repeaters to create LFE templates and find that the templates created from both tremor types are very similar. To test their similarity, we use both interchangeably and find that most of both the ambient and triggered tremor match the LFE templates created from either data set, suggesting that LFEsmore » for both events have a common origin. Finally, we locate the LFEs by using local earthquake P wave and S wave information and find that LFEs from triggered and ambient tremor locate to between 20 and 35 km on what we interpret as the deep extension of the Chaochou-Lishan Fault.« less

NASA's Space Launch System: Deep-Space Opportunities for SmallSats

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Schorr, Andrew A.

2017-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight test of the Orion spacecraft around the moon, accompanying Orion on SLS will be small-satellite secondary payloads, which will deploy in cislunar space. The deployment berths are sized for "6U" CubeSats, and on EM-1 the spacecraft will be deployed into cislunar space following Orion separate from the SLS Interim Cryogenic Propulsion Stage. Payloads in 6U class will be limited to 14 kg maximum mass. Secondary payloads on EM-1 will be launched in the Orion Stage Adapter (OSA). Payload dispensers will be mounted on specially designed brackets, each attached to the interior wall of the OSA. For the EM-1 mission, a total of fourteen brackets will be installed, allowing for thirteen payload locations. The final location will be used for mounting an avionics unit, which will include a battery and sequencer for executing the mission deployment sequence. Following the launch of EM-1, deployments of the secondary payloads will commence after sufficient separation of the Orion spacecraft to the upper stage vehicle to minimize any possible contact of the deployed cubesats to Orion. Currently this is estimated to require approximately 4 hours. The allowed deployment window for the cubesats will be from the time the upper stage disposal maneuvers are complete to up to 10 days after launch. The upper stage will fly past the moon at a perigee of approximately 100km, and this closest approach will occur about 5 days after launch. The limiting factor for the latest deployment time is the available power in the sequencer system. Several NASA Mission Directorates were involved in the development of programs for the competition, selection, and development of EM-1 payloads that support directorate priorities. CubeSat payloads on EM-1 will include both NASA research experiments and spacecraft developed by industry, international and potentially academia partners. The Human Exploration and Operations Mission Directorate (HEOMD) Advanced Exploration Systems (AES) Division was allocated five payload opportunities on the EM-1 mission. Near Earth Asteroid (NEA) Scout is designed to rendezvous with and characterize a candidate NEA. A solar sail, an innovation the spacecraft will demonstrated for the CubeSat class, will provide propulsion. Lunar Flashlight will use a green propellant system and will search for potential ice deposits in the moon's permanently shadowed craters. BioSentinel is a yeast radiation biosensor, planned to measure the effects of space radiation on deoxyribonucleic acid (DNA). Lunar Icecube, a collaboration with Morehead State University, will prospect for water in ice, liquid, and vapor forms as well as other lunar volatiles from a low-perigee, highly inclined lunar orbit using a compact Infrared spectrometer. Skyfire, a partnership with Lockheed Martin, is a technology demonstration mission that will perform a lunar flyby, collecting spectroscopy, and thermography data to address questions related to surface characterization, remote sensing, and site selection. NASA's Space Technology Mission Directorate (STMD) was allocated three payload opportunities on the EM-1 mission. These slots will be filled via the 2 Centennial Challenges Program, NASA's flagship program for technology prize competitions, which directly engages the public, academia, and industry in open prize competitions to stimulate innovation. The NASA Science Mission Directorate (SMD) was allocated two payload opportunities on the EM-1 mission. The CubeSat Mission to Study Solar Particles (CuSP) payload will study the sources and acceleration mechanisms of solar and interplanetary particles in near-Earth orbit, support space weather research by determining proton radiation levels during Solar Energetic Particle (SEP) events and identifying suprathermal properties that could help predict geomagnetic storms. The LunaH-Map payload will help scientists understand the quantity of H-bearing materials in lunar cold traps (10 km), determine the concentration of H-bearing materials with 1m depth, and constrain the vertical distribution of H-bearing materials. The final three payload opportunities for the EM-1 mission were allocated for NASA's international space agency counterparts. The flight opportunities are intended to benefit the international space agency and NASA as well as further the collective space exploration goals. ArgoMoon is sponsored by ESA/ASI and will fly along with the ICPS on its disposal trajectory to perform proximity operations with the ICPS post-disposal, take external imagery of engineering and historical significance, and perform an optical communications demonstration. EQUULEUS, sponsored by JAXA, will fly to a libration orbit around the Earth-Moon L2 point and demonstrate trajectory control techniques within the Sun-Earth-Moon region for the first time by a nano spacecraft. The mission will also contribute to the future human exploration scenario by understanding the radiation environment in geospace and deep space, characterizing the flux of impacting meteors on the far side of the moon, and demonstrating the future deep space exploration scenario using the "deep space port" at Lagrange points. OMOTENASHI, also sponsored by JAXA, will land the smallest lunar lander to date on the lunar surface to demonstrate the feasibility of the hardware for distributed cooperative exploration system. Small landers will enable multi-point exploration, which is complimentary with large-scale human exploration. Once on the lunar surface, the OMOTENASHI spacecraft will observe the radiation and soil environments of the lunar surface by active radiation measurements and soil shear measurements. Following EM-1, Space Launch System will evolve to the more-powerful Block 1B configuration, which uses a new Exploration Upper Stage to increase the vehicle's LEO payload capability from 70 t to 105 t. With that transition, the Orion Stage Adapter, which will carry the secondary payloads on EM-1, will be phased out, and a new Universal Stage Adapter will be introduced, creating opportunities for flying larger secondary payloads. This paper will provide a brief status of SLS progress toward first launch; an overview of smallsat accommodations, integration, and operations on EM-1; information about the specific payloads flying on that launch; and a discussion of future accommodations and opportunities for secondary payloads on SLS for Exploration Mission-2 and beyond.

NASA's Space Launch System: Deep-Space Delivery for Smallsats

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Norris, George

2017-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight test of the Orion spacecraft around the moon, accompanying Orion on SLS will be small-satellite secondary payloads, which will deploy in cislunar space. The deployment berths are sized for "6U" CubeSats, and on EM-1 the spacecraft will be deployed into cislunar space following Orion separate from the SLS Interim Cryogenic Propulsion Stage. Payloads in 6U class will be limited to 14 kg maximum mass. Secondary payloads on EM-1 will be launched in the Orion Stage Adapter (OSA). Payload dispensers will be mounted on specially designed brackets, each attached to the interior wall of the OSA. For the EM-1 mission, a total of fourteen brackets will be installed, allowing for thirteen payload locations. The final location will be used for mounting an avionics unit, which will include a battery and sequencer for executing the mission deployment sequence. Following the launch of EM-1, deployments of the secondary payloads will commence after sufficient separation of the Orion spacecraft to the upper stage vehicle to minimize any possible contact of the deployed CubeSats to Orion. Currently this is estimated to require approximately 4 hours. The allowed deployment window for the CubeSats will be from the time the upper stage disposal maneuvers are complete to up to 10 days after launch. The upper stage will fly past the moon at a perigee of approximately 100km, and this closest approach will occur about 5 days after launch. The limiting factor for the latest deployment time is the available power in the sequencer system. Several NASA Mission Directorates were involved in the development of programs for the competition, selection, and development of EM-1 payloads that support directorate priorities. CubeSat payloads on EM-1 will include both NASA research experiments and spacecraft developed by industry, international and potentially academia partners. The Human Exploration and Operations Mission Directorate (HEOMD) Advanced Exploration Systems (AES) Division was allocated five payload opportunities on the EM-1 mission. Near Earth Asteroid (NEA) Scout is designed to rendezvous with and characterize a candidate NEA. A solar sail, an innovation the spacecraft will demonstrated for the CubeSat class, will provide propulsion. Lunar Flashlight will use a green propellant system and will search for potential ice deposits in the moon's permanently shadowed craters. BioSentinel is a yeast radiation biosensor, planned to measure the effects of space radiation on deoxyribonucleic acid (DNA). Lunar Icecube, a collaboration with Morehead State University, will prospect for water in ice, liquid, and vapor forms as well as other lunar volatiles from a low-perigee, highly inclined lunar orbit using a compact Infrared spectrometer. Skyfire, a partnership with Lockheed Martin, is a technology demonstration mission that will perform a lunar flyby, collecting spectroscopy, and thermography data to address questions related to surface characterization, remote sensing, and site selection. NASA's Space Technology Mission Directorate (STMD) was allocated three payload opportunities on the EM-1 mission. These slots will be filled via the Centennial Challenges Program, NASA's flagship program for technology prize competitions, which directly engages the public, academia, and industry in open prize competitions to stimulate innovation. The NASA Science Mission Directorate (SMD) was allocated two payload opportunities on the EM-1 mission. The CubeSat Mission to Study Solar Particles (CuSP) payload will study the sources and acceleration mechanisms of solar and interplanetary particles in near-Earth orbit, support space weather research by determining proton radiation levels during Solar Energetic Particle (SEP) events and identifying suprathermal properties that could help predict geomagnetic storms. The LunaH-Map payload will help scientists understand the quantity of H-bearing materials in lunar cold traps (10 km), determine the concentration of H-bearing materials with 1m depth, and constrain the vertical distribution of H-bearing materials. The final three payload opportunities for the EM-1 mission were allocated for NASA's international space agency counterparts. The flight opportunities are intended to benefit the international space agency and NASA as well as further the collective space exploration goals. ArgoMoon is sponsored by ESA/ASI and will fly along with the ICPS on its disposal trajectory to perform proximity operations with the ICPS post-disposal, take external imagery of engineering and historical significance, and perform an optical communications demonstration. EQUULEUS, sponsored by JAXA, will fly to a libration orbit around the Earth-Moon L2 point and demonstrate trajectory control techniques within the Sun-Earth- Moon region for the first time by a nano spacecraft. The mission will also contribute to the future human exploration scenario by understanding the radiation environment in geospace and deep space, characterizing the flux of impacting meteors on the far side of the moon, and demonstrating the future deep space exploration scenario using the "deep space port" at Lagrange points. OMOTENASHI, also sponsored by JAXA, will land the smallest lunar lander to date on the lunar surface to demonstrate the feasibility of the hardware for distributed cooperative exploration system. Small landers will enable multi-point exploration, which is complimentary with large-scale human exploration. Once on the lunar surface, the OMOTENASHI spacecraft will observe the radiation and soil environments of the lunar surface by active radiation measurements and soil shear measurements. Following EM-1, Space Launch System will evolve to the more-powerful Block 1B configuration, which uses a new Exploration Upper Stage to increase the vehicle's LEO payload capability from 70 t to 105 t. With that transition, the Orion Stage Adapter, which will carry the secondary payloads on EM-1, will be phased out, and a new Universal Stage Adapter will be introduced, creating opportunities for flying larger secondary payloads. This paper will provide a brief status of SLS progress toward first launch; an overview of smallsat accommodations, integration, and operations on EM-1; information about the specific payloads flying on that launch; and a discussion of future accommodations and opportunities for secondary payloads on SLS for Exploration Mission-2 and beyond.

International lunar observatory / power station: from Hawaii to the Moon

NASA Astrophysics Data System (ADS)

Durst, S.

Astronomy's great advantages from the Moon are well known - stable surface, diffuse atmosphere, long cool nights (14 days), low gravity, far side radio frequency silence. A large variety of astronomical instruments and observations are possible - radio, optical and infrared telescopes and interferometers; interferometry for ultra- violet to sub -millimeter wavelengths and for very long baselines, including Earth- Moon VLBI; X-ray, gamma-ray, cosmic ray and neutrino detection; very low frequency radio observation; and more. Unparalleled advantages of lunar observatories for SETI, as well as for local surveillance, Earth observation, and detection of Earth approaching objects add significant utility to lunar astronomy's superlatives. At least nine major conferences in the USA since 1984 and many elsewhere, as well as ILEWG, IAF, IAA, LEDA and other organizations' astronomy-from-the-Moon research indicate a lunar observatory / power station, robotic at first, will be one of the first mission elements for a permanent lunar base. An international lunar observatory will be a transcending enterprise, highly principled, indispensable, soundly and broadly based, and far- seeing. Via Astra - From Hawaii to the Moon: The astronomy and scie nce communities, national space agencies and aerospace consortia, commercial travel and tourist enterprises and those aspiring to advance humanity's best qualities, such as Aloha, will recognize Hawaii in the 21st century as a new major support area and pan- Pacific port of embarkation to space, the Moon and beyond. Astronomical conditions and facilities on Hawaii's Mauna Kea provide experience for construction and operation of observatories on the Moon. Remote and centrally isolated, with diffuse atmosphere, sub-zero temperature and limited working mobility, the Mauna Kea complex atop the 4,206 meter summit of the largest mountain on the planet hosts the greatest collection of large astronomical telescopes on Earth. Lunar, extraterrestrial-like lava flow geology adds to Mauna Kea / Moon similarities. Operating amidst the extinct volcano's fine grain lava and dust particles offers experience for major challenges posed by silicon-edged, powdery, deep and abundant lunar regolith. Power stations for lunar observatories, both robotic and low cost at first, are an immediate enabling necessity and will serve as a commercial-industrial driver for a wide range of lunar base technologies. Both microwave rectenna-transmitters and radio-optical telescopes, maybe 1-meter diameter, can be designed using the same, new ultra-lightweight materials. Five of the world's six major spacefaring powers - America, Russia, Japan, China and India, are located around Hawaii in the Pacific / Asia area. With Europe, which has many resources in the Pacific hemisphere including Arianespace offices in Tokyo and Singapore, they have 55-60% of the global population. New international business partnerships such as Sea Launch in the mid-Pacific, and national ventures like China's Hainan spaceport, Japan's Kiribati shuttle landing site, Australia and Indonesia's emerging launch sites, and Russia's Ekranoplane sea launcher / lander - all combine with still more and advancing technologies to provide the central Pacific a globally representative, state-of-the-art and profitable access to space in this new century. The astronomer / engineers tasked with operation of the lunar observatory / power station will be the first to voyage from Hawaii to the Moon, before this decade is out. Their scientific and technical training at the world's leading astronomical complex on the lunar-like landscape of Mauna Kea may be enhanced with the learning and transmission of local cultures. Following the astronomer / engineers, tourism and travel in the commercially and technologically dynamic Pacific hemisphere will open the new ocean of space to public access in the 21st century like they opened the old ocean of sea and air to Hawaii in the 20th - with Hawaii becoming the place to go to honeymoon, and to go to the Moon. A world apart, Hawaii, with its microgravity environment, is part way in space already, a stepping stone to the Moon, stars, and beyond. References 1. NASA Technical Memorandum 4757; Paul D. Lowman Jr, "Lunar Limb Observatory", An Incremental Plan for the Utilization, Exploration and Settlement of the Moon; Goddard Space Flight Center, October 1996. 2. Japan NASDA Report 61; "An Infinity of Twinkling Stars Visible from the Moon", The Day the Moon Becomes the Heartland of Humankind - Series 4; July 1997. 3. China Space Flight High Tech Program 863; "Research on the Necessity and Feasibility of Lunar Exploration in our Country"; May 1995. 4. European Space Agency SP-1150; "Mission to the Moon", Europe's Priorities for the Scientific Exploration and Utilization of the Moon; 1992. 5. Lavochkin Association; Company Prospectus; Moscow, Russia; August 1995. 6. India Space Research Organization; Lunar Spacecraft 2005 Feasibility Study; Bangalore; due late 2000. 7. "International Lunar Observatory", Steve Durst; 3rd International Conference on Exploration and Utilization of the Moon; Russian Academy of Sciences, Moscow; October 1998. 8. "Lunar Observatories: Why, Where, and When?"; Paul D. Lowman Jr, Peter C. Chen, Steve Durst; 8th International Space Conference of Pacific -basin Societies; Xian, China; June 1999. 9. "International Lunar Observatory: From Hawaii to the Moon", Steve Durst; 4th International Conference on Exploration and Utilization of the Moon; ESA / ESTEC, Noordwijk, The Netherlands, July 2000. (Paper Revised; Prepared for but not Presented to the 2nd Annual Lunar Development Conference: `Return to the Moon II' 20-21 July 2000, Caesars Palace, Las Vegas, Nevada)

Deep Tectonic Tremor in Haiti triggered by the 2010/02/27 Mw8.8 Maule, Chile earthquake

NASA Astrophysics Data System (ADS)

Aiken, C.; Peng, Z.; Douilly, R.; Calais, E.; Deschamps, A.; Haase, J. S.

2013-05-01

Tectonic tremors have been observed along major plate-boundary faults around the world. In most of these regions, tremors occur spontaneously (i.e. ambient) or as a result of small stress perturbations from passing surface waves (i.e. triggered). Because tremors are located below the seismogenic zone, a detailed study of their behavior could help to better understand how tectonic movement is accommodated in the deep root of major faults, and the relationship with large earthquakes. Here, we present evidence of triggered tremor in southern Haiti around the aftershock zone of the 2010/01/12 Mw7.0 Haiti earthquake. Following the January mainshock, several groups have installed land and ocean bottom seismometers to record aftershock activity (e.g., De Lepinay et al., 2011). In the following month, the 2010/02/27 Mw8.8 Maule, Chile earthquake occurred and was recorded in the southern Haiti region by these seismic stations. We apply a 5-15 Hz band-pass filter to all seismograms to identify local high-frequency signals during the Chile teleseismic waves. Tremor is identified as non-impulsive bursts with 10-20 s durations that is coherent among different stations and is modulated by surface waves. We also convert the seismic data into audible sounds and use them to distinguish between local aftershocks and deep tremor. We locate the source of the tremor bursts using an envelope cross-correlation method based on travel time differences. Because tremor depth is not well constrained with this method, we set it to 20 km, close to the recent estimate of Moho depth in this region (McNamara et al., 2012). Most tremors are located south of the surface expression of the Enriquillo-Plantain Garden Fault (EPGF), a high-angle southward dipping left-lateral strike-slip fault that marks the boundary between the Gonave microplate and the Caribbean plate, although the location errors are large. Tremor peaks are mostly modulated by Love wave velocity, which is consistent with left-lateral shear motion induced by the normal incidence of Love wave on a near-vertical strike-slip fault. Our ongoing efforts include comparing tremor and aftershock locations with the same envelope techniques, and identifying tremor at other times. If the tremor locations are reliable, the results pose interesting questions about stress changes following the Haiti mainshock that lead to triggered seismicity on the shallow south dipping Trois Baies fault (De Lepinay et al., 2011, Douilly et al, 2013), and triggered tremor on the EPGF, where no aftershocks were recorded.

New Opportunities for Outer Solar System Science using Radioisotope Electric Propulsion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noble, Robert J.; /SLAC; Amini, Rashied

Today, our questions and hypotheses about the Solar System's origin have surpassed our ability to deliver scientific instruments to deep space. The moons of the outer planets, the Trojan and Centaur minor planets, the trans-Neptunian objects (TNO), and distant Kuiper Belt objects (KBO) hold a wealth of information about the primordial conditions that led to the formation of our Solar System. Robotic missions to these objects are needed to make the discoveries, but the lack of deep-space propulsion is impeding this science. Radioisotope electric propulsion (REP) will revolutionize the way we do deep-space planetary science with robotic vehicles, giving themmore » unprecedented mobility. Radioisotope electric generators and lightweight ion thrusters are being developed today which will make possible REP systems with specific power in the range of 5 to 10 W/kg. Studies have shown that this specific power range is sufficient to perform fast rendezvous missions from Earth to the outer Solar System and fast sample return missions. This whitepaper discusses how mobility provided by REP opens up entirely new science opportunities for robotic missions to distant primitive bodies. We also give an overview of REP technology developments and the required next steps to realize REP.« less

Deep space telecommunications, navigation, and information management. Support of the space exploration initiative

NASA Astrophysics Data System (ADS)

Hall, Justin R.; Hastrup, Rolf C.

The United States Space Exploration Initiative (SEI) calls for the charting of a new and evolving manned course to the Moon, Mars, and beyond. This paper discusses key challenges in providing effective deep space telecommunications, navigation, and information management (TNIM) architectures and designs for Mars exploration support. The fundamental objectives are to provide the mission with means to monitor and control mission elements, acquire engineering, science, and navigation data, compute state vectors and navigate, and move these data efficiently and automatically between mission nodes for timely analysis and decision-making. Although these objectives do not depart, fundamentally, from those evolved over the past 30 years in supporting deep space robotic exploration, there are several new issues. This paper focuses on summarizing new requirements, identifying related issues and challenges, responding with concepts and strategies which are enabling, and, finally, describing candidate architectures, and driving technologies. The design challenges include the attainment of: 1) manageable interfaces in a large distributed system, 2) highly unattended operations for in-situ Mars telecommunications and navigation functions, 3) robust connectivity for manned and robotic links, 4) information management for efficient and reliable interchange of data between mission nodes, and 5) an adequate Mars-Earth data rate.

Non-pharmacologic management of sickle cell pain.

PubMed

Bodhise, Paul Brown; Dejoie, Marjorie; Brandon, Zemoria; Simpkins, Stanley; Ballas, Samir K

2004-06-01

Patients with sickle cell disease (SCD) suffer from both acute and chronic pain. The latter includes avascular necrosis of the hip joints mostly in the adult population. It has a negative impact on the quality of life of affected individuals and is often associated with depression, disability, unemployment and dependence on opioid analgesics. In this study, we show that a non-pharmacologic approach to management with deep tissue/deep pressure massage therapy technique, including neuromuscular trigger point treatment with acupressure, in patients with SCD has a salutary effect on pain relief and quality of life. Copyright 2004 Taylor and Francis Ltd

Geologic carbon storage is unlikely to trigger large earthquakes and reactivate faults through which CO2 could leak

PubMed Central

Vilarrasa, Victor; Carrera, Jesus

2015-01-01

Zoback and Gorelick [(2012) Proc Natl Acad Sci USA 109(26):10164–10168] have claimed that geologic carbon storage in deep saline formations is very likely to trigger large induced seismicity, which may damage the caprock and ruin the objective of keeping CO2 stored deep underground. We argue that felt induced earthquakes due to geologic CO2 storage are unlikely because (i) sedimentary formations, which are softer than the crystalline basement, are rarely critically stressed; (ii) the least stable situation occurs at the beginning of injection, which makes it easy to control; (iii) CO2 dissolution into brine may help in reducing overpressure; and (iv) CO2 will not flow across the caprock because of capillarity, but brine will, which will reduce overpressure further. The latter two mechanisms ensure that overpressures caused by CO2 injection will dissipate in a moderate time after injection stops, hindering the occurrence of postinjection induced seismicity. Furthermore, even if microseismicity were induced, CO2 leakage through fault reactivation would be unlikely because the high clay content of caprocks ensures a reduced permeability and increased entry pressure along the localized deformation zone. For these reasons, we contend that properly sited and managed geologic carbon storage in deep saline formations remains a safe option to mitigate anthropogenic climate change. PMID:25902501

Estimation of a melting probe's penetration velocity range to reach icy moons' subsurface ocean

NASA Astrophysics Data System (ADS)

Erokhina, Olga; Chumachenko, Eugene

2014-05-01

In modern space science one of the actual branches is icy satellites explorations. The main interest is concentrated around Jovian's moons Europa and Ganymede, Saturn's moons Titan and Enceladus that are covered by thick icy layer according to "Voyager1", "Voyager2", "Galileo" and "Cassini" missions. There is a big possibility that under icy shell could be a deep ocean. Also conditions on these satellites allow speculating about possible habitability, and considering these moons from an astrobiological point of view. One of the possible tasks of planned missions is a subsurface study. For this goal it is necessary to design special equipment that could be suitable for planetary application. One of the possible means is to use a melting probe which operates by melting and moves by gravitational force. Such a probe should be relatively small, should not weight too much and should require not too much energy. In terrestrial case such kind of probe has been successfully used for glaciers study. And it is possible to extrapolate the usage of such probe to extraterrestrial application. One of the tasks is to estimate melting probe's penetration velocity. Although there are other unsolved problems such as analyzing how the probe will move in low gravity and low atmospheric pressure; knowing whether hole will be closed or not when probe penetrate thick enough; and considering what order could be a penetration velocity. This study explores two techniques of melting probe's movement. One of them based on elasto-plastic theory and so-called "solid water" theory, and other one takes phase changing into account. These two techniques allow estimating melting probe's velocity range and study whole process. Based on these technique several cases of melting probe movement were considered, melting probe's velocity range estimated, influence of different factors studied and discussed and an easy way to optimize parameters of the melting probe proposed.

FERMI Observations of Gamma -Ray Emission From the Moon

NASA Technical Reports Server (NTRS)

Abdo, A. A.; Ackermann, M.; Ajello, M.; Atwoo, W. B.; Baldini, I.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.;

Deep-sea bioluminescence blooms after dense water formation at the ocean surface.

PubMed

Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Moscoso, Luciano; Motz, Holger; Neff, Max; Nezri, Emma Nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J M; Stolarczyk, Thierry; Taiuti, Mauro G F; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan

2013-01-01

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as "open-sea convection". It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts.

California State Waters Map Series: offshore of Half Moon Bay, California

USGS Publications Warehouse

Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Johnson, Samuel Y.; Golden, Nadine E.; Hartwell, Stephen R.; Dieter, Bryan E.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Watt, Janet T.; Endris, Charles A.; Kvitek, Rikk G.; Phillips, Eleyne L.; Erdey, Mercedes D.; Chin, John L.; Bretz, Carrie K.

2014-01-01

In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. The Offshore of Half Moon Bay map area is located in northern California, on the Pacific coast of the San Francisco Peninsula about 40 kilometers south of the Golden Gate. The city of Half Moon Bay, which is situated on the east side of the Half Moon Bay embayment, is the nearest significant onshore cultural center in the map area, with a population of about 11,000. The Pillar Point Harbor at the north edge of Half Moon Bay offers a protected landing for boats and provides other marine infrastructure. The map area lies offshore of the Santa Cruz Mountains, part of the northwest-trending Coast Ranges that run roughly parallel to the San Andreas Fault Zone. The Santa Cruz Mountains lie between the San Andreas Fault Zone and the San Gregorio Fault system. The flat coastal area, which is the most recent of numerous marine terraces, was formed by wave erosion about 105 thousand years ago. The higher elevation of this same terrace west of the Half Moon Bay Airport is caused by uplift on the Seal Cove Fault, a splay of the San Gregorio Fault Zone. Although originally incised into the rising terrain horizontally, the ancient terrace surface has been gently folded into a northwest-plunging syncline by compression related to right-lateral strike-slip movement along the San Gregorio Fault Zone. The lowest elevation coincides with the deepest part of Half Moon Bay; the terrace surface rises both to the north and to the south. Uplift in this map area has resulted in relatively shallow water depths within California’s State Waters and, thus, little accommodation space for sediment accumulation. Sediment is observed in the shelter of Half Moon Bay and on the outer half of the California’s State Waters shelf. Sediment in the area is mobile, often forming dunes and sand waves. A westward bend in the San Andreas Fault Zone, southeast of the map area, coupled with right-lateral movement along the Seal Cove Fault, which comes ashore in Pillar Point Harbor, has resulted in the folding and uplifting of sedimentary rocks of the Purisima Formation in the offshore. Differential erosion of these folded and faulted layers of the Purisima Formation has exposed the parallel curved-rock ridges that are visible on the seafloor from the headland at Pillar Point. During the winter, strong North Pacific storms generate large, long-period waves that shoal and break over this bedrock reef at the world-famous surfing location known as Mavericks. The Offshore of Half Moon Bay map area lies within the cold-temperate biogeographic zone that is called either the “Oregonian province” or the “northern California ecoregion.” This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, an eastern limb of the North Pacific subtropical gyre that flows from Oregon to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 365 km south of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off central California has experienced a warming over the last 50 years that is driving an ecosystem shift away from the productive subarctic regime towards a depopulated subtropical environment. Seafloor habitats in the Offshore of Half Moon Bay map area, which lies within the Shelf (continental shelf) megahabitat, range from significant rocky outcrops that support kelp-forest communities nearshore to rocky-reef communities in deep water. Biological productivity resulting from coastal upwelling supports populations of sea birds such as Sooty Shearwater, Western Gull, Common Murre, Cassin’s Auklet, and many other less populous bird species. In addition, an observable recovery of Humpback and Blue Whales has occurred in the area; both species are dependent on coastal upwelling to provide nutrients. The large extent of exposed inner shelf bedrock supports large forests of “bull kelp,” which is well adapted for high wave-energy environments. Common fish species found in the kelp beds and rocky reefs include lingcod and various species of rockfish and greenling.

Clementine: An inexpensive mission to the Moon and Geographos

NASA Astrophysics Data System (ADS)

Shoemaker, Eugene M.; Nozette, Stewart

1993-03-01

The Clementine Mission, a joint project of the Strategic Defense Initiative Organization (SDIO) and NASA, has been planned primarily to test and demonstrate a suite of lightweight sensors and other lightweight spacecraft components under extended exposure to the space environment. Although the primary objective of the mission is to space-qualify sensors for Department of Defense applications, it was recognized in 1990 that such a mission might also be designed to acquire scientific observations of the Moon and of Apollo asteroid (1620) Geographos. This possibility was explored jointly by SDIO and NASA, including representatives from NASA's Discovery Program Science Working Group, in early 1991. Besides the direct return of scientific information, one of the benefits envisioned from a joint venture was the development of lightweight components for possible future use in NASA's Discovery-class spacecraft. In Jan. 1992, SDIO informed NASA of its intent to fly a 'Deep Space Program Science Experiment,' now popularly called Clementine; NASA then formed an advisory science working group to assist in the early development of the mission. The Clementine spacecraft is being assembled at the Naval Research Laboratory, which is also in charge of the overall mission design and mission operations. Support for mission design is being provided by GSFC and by JPL. NASA's Deep Space Network will be utilized in tracking and communicating with the spacecraft. Following a recommendation of the COMPLEX committee of the Space Science Board, NASA will issue an NRA and appoint a formal science team in early 1993. Clementine is a 3-axis stabilized, 200 kg (dry weight) spacecraft that will be launched on a refurbished Titan-2G. One of the goals has been to build two spacecraft, including the sensors, for $100M. Total time elapsed from the decision to proceed to the launch will be two years.

Origin and Constraints on Ilmenite-rich Partial Melt in the Lunar Lower Mantle

NASA Astrophysics Data System (ADS)

Mallik, A.; Fuqua, H.; Bremner, P. M.; Panovska, S.; Diamond, M. R.; Lock, S. J.; Nishikawa, Y.; Jiménez-Pérez, H.; Shahar, A.; Panero, W. R.; Lognonne, P. H.; Faul, U.

2015-12-01

Existence of a partially molten layer at the lunar core-mantle boundary has been proposed to explain the lack of observed far-side deep moonquakes, the observation of reflected seismic phases from deep moonquakes, and the dissipation of tidal energy within the lunar interior [1,2]. However, subsequent models explored the possibility that dissipation due to elevated temperatures alone can explain the observed dissipation factor (Q) and tidal love numbers [3]. Using thermo-chemical and dynamic modeling (including models of the early lunar mantle convection), we explore the hypothesis that an ilmenite-rich layer forms below crustal anorthosite during lunar magma ocean crystallization and may sink to the base of the mantle to create a partial melt layer at the lunar core-mantle boundary. Self-consistent physical parameters (including gravity, pressure, density, VP and Vs) are forward calculated for a well-mixed mantle with uniform bulk composition versus a mantle with preserved mineralogical stratigraphy from lunar magma ocean crystallization. These parameters are compared against observed mass, moment of inertia, real and imaginary parts of the Love numbers, and seismic travel times to further limit the acceptable models for the Moon. We have performed a multi-step grid search with over twenty thousand forward calculations varying thicknesses of chemically/mineralogically distinct layers within the Moon to evaluate if a partially molten layer at the base of the lunar mantle is well-constrained by the observed data. Furthermore, dynamic mantle modeling was employed on the best-fit model versions to determine the survivability of a partially molten layer at the core-mantle boundary. This work was originally initiated at the CIDER 2014 program. [1] Weber et al. (2011). Science 331(6015), 309-12. [2] Khan et al. (2014). JGR 119. [3] Nimmo et al. (2012). JGR 117, 1-11.

Confusion and Complex Learning during Interactions with Computer Learning Environments

ERIC Educational Resources Information Center

Lehman, Blair; D'Mello, Sidney; Graesser, Art

2012-01-01

Folk wisdom holds that being confused is detrimental to learning. However, research on emotions and learning suggest a somewhat more complex relationship between confusion and learning outcomes. In fact, it has been proposed that impasses that trigger states of cognitive disequilibrium and confusion can create opportunities for deep learning of…

NASA's Space Launch System: Deep-Space Delivery for SmallSats

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Norris, George

2017-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering more than 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, an uncrewed test of the Orion spacecraft into distant retrograde orbit around the moon, accompanying Orion on SLS will be 13 small-satellite secondary payloads, which will deploy in cislunar space. These secondary payloads will include not only NASA research, but also spacecraft from industry and international partners and academia. The payloads also represent a variety of disciplines including, but not limited to, studies of the moon, Earth, sun, and asteroids. The Space Launch System Program is working actively with the developers of the payloads toward vehicle integration. Following its first flight and potentially as early as its second, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO, and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from those on the first launch, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for small satellites. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the opportunities the vehicle offers for small satellites, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018 and a discussion of future capabilities.

Acquiring High-Performance Deep-Blue OLED Emitters through an Unexpected Blueshift Color-Tuning Effect Induced by Electron-Donating -OMe Substituents.

PubMed

Peng, Song; Zhao, Yihuan; Fu, Caixia; Pu, Xuemei; Zhou, Liang; Huang, Yan; Lu, Zhiyun

2018-06-07

A series of blue-emissive 7-(diphenylamino)-4-phenoxycoumarin derivatives bearing -CF 3 , -OMe, or -N(Me) 2 substituents on the phenoxy subunit were synthesized. Although both the -CF 3 and -N(Me) 2 modifications were found to trigger redshifted fluorescence, the -OMe substitution was demonstrated to exert an unexpected blueshift color-tuning effect toward the deep-blue region. The reason is that the moderate electron-donating -OMe group can endow coumarins with unaltered HOMO but elevated LUMO energy levels. Moreover, the -OMe substitution was found to be beneficial to the thermal stability of these coumarins. Therefore, the trimethoxy-substituted objective compound can act as a high-performance deep-blue organic light-emitting diode (OLED) emitter, and OLED based on it emits deep-blue light with CIE coordinates of (0.148, 0.084), maximum luminance of 7800 cd m -2 , and maximum external quantum efficiency of 5.1 %. These results not only shed light on the molecular design strategy for high-performance deep-blue OLED emitters through color-tuning, but also show the perspective of coumarin derivatives as deep-blue OLED emitters. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improvement of digestive complaints in women with severe colorectal endometriosis benefiting from continuous amenorrhoea triggered by triptorelin. A prospective pilot study.

PubMed

Roman, H; Saint Ghislain, M; Milles, M; Marty, N; Hennetier, C; Moatassim, S; Desnyder, E; Abo, C

2015-09-01

To assess the impact of therapeutic amenorrhoea triggered by triptorelin in the digestive complaints of women with deep endometriosis infiltrating the rectum. Prospective series of consecutive patients with deep endometriosis of the rectum enrolled over a period of 17 consecutive months. University tertiary referral center. Seventy patients. Medical therapy (triptorelin 11.25 mg and add-back therapy using estradiol) administered for 3.4±1.8months before surgery. Gastrointestinal standardised questionnaires before beginning medical treatment and the day before surgery. The most frequent digestive complaints at baseline were: defecation pain in 77.1% of patients, bloating in 60%, diarrhoea in 54.3% and constipation in 50%. The largest diameter of the rectal area infiltrated by the disease was <1cm in 12.2% of women, 1 to 2.9 cm in 34.3% and ≥3cm in 51.4%. Multiple colorectal nodules were found in 32.9%. Medical treatment led to disappearance of cyclic defecation pain in 78.6%, dyschesia in 58.3%, diarrhoea in 58.3% and bloating in 50%. Relieving digestive complaints was not significantly related to either length of triptorelin administration or size of rectal infiltration by deep endometriosis. Therapeutic amenorrhoea averaging 3 months allowed complete improvement of various cyclic digestive complaints in more than half of patients. In selected patients, continuous therapeutic amenorrhoea could compensate for the lack of complete resection of deep infiltrating endometriosis of the rectum, when this latter is likely to result in a high rate of postoperative morbidity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

The Role of Deep Creep in the Timing of Large Earthquakes

NASA Astrophysics Data System (ADS)

Sammis, C. G.; Smith, S. W.

2012-12-01

The observed temporal clustering of the world's largest earthquakes has been largely discounted for two reasons: a) it is consistent with Poisson clustering, and b) no physical mechanism leading to such clustering has been proposed. This lack of a mechanism arises primarily because the static stress transfer mechanism, commonly used to explain aftershocks and the clustering of large events on localized fault networks, does not work at global distances. However, there is recent observational evidence that the surface waves from large earthquakes trigger non-volcanic tremor at the base of distant fault zones at global distances. Based on these observations, we develop a simple non-linear coupled oscillator model that shows how the triggering of such tremor can lead to the synchronization of large earthquakes on a global scale. A basic assumption of the model is that induced tremor is a proxy for deep creep that advances the seismic cycle of the fault. We support this hypothesis by demonstrating that the 2010 Maule Chile and the 2011 Fukushima Japan earthquakes, which have been shown to induce tremor on the Parkfield segment of the San Andreas Fault, also produce changes in off-fault seismicity that are spatially and temporally consistent with episodes of deep creep on the fault. The observed spatial pattern can be simulated using an Okada dislocation model for deep creep (below 20 km) on the fault plane in which the slip rate decreases from North to South consistent with surface creep measurements and deepens south of the "Parkfield asperity" as indicated by recent tremor locations. The model predicts the off-fault events should have reverse mechanism consistent with observed topography.

Meteorological variables to aid forecasting deep slab avalanches on persistent weak layers

USGS Publications Warehouse

Marienthal, Alex; Hendrikx, Jordy; Birkeland, Karl; Irvine, Kathryn M.

2015-01-01

Deep slab avalanches are particularly challenging to forecast. These avalanches are difficult to trigger, yet when they release they tend to propagate far and can result in large and destructive avalanches. We utilized a 44-year record of avalanche control and meteorological data from Bridger Bowl ski area in southwest Montana to test the usefulness of meteorological variables for predicting seasons and days with deep slab avalanches. We defined deep slab avalanches as those that failed on persistent weak layers deeper than 0.9 m, and that occurred after February 1st. Previous studies often used meteorological variables from days prior to avalanches, but we also considered meteorological variables over the early months of the season. We used classification trees and random forests for our analyses. Our results showed seasons with either dry or wet deep slabs on persistent weak layers typically had less precipitation from November through January than seasons without deep slabs on persistent weak layers. Days with deep slab avalanches on persistent weak layers often had warmer minimum 24-hour air temperatures, and more precipitation over the prior seven days, than days without deep slabs on persistent weak layers. Days with deep wet slab avalanches on persistent weak layers were typically preceded by three days of above freezing air temperatures. Seasonal and daily meteorological variables were found useful to aid forecasting dry and wet deep slab avalanches on persistent weak layers, and should be used in combination with continuous observation of the snowpack and avalanche activity.

Harvest Moon at NASA Goddard

NASA Image and Video Library

2017-12-08

September's Harvest Moon as seen around NASA's Goddard Space Flight Center. According to folklore, every full Moon has a special name. There's the Wolf Moon, the Snow Moon, the Worm Moon, the Sprouting Grass Moon, the Flower Moon, the Strawberry Moon, the Thunder Moon, the Sturgeon Moon, the Harvest Moon, the Hunter's Moon, the Beaver Moon, and the Long Night's Moon. Each name tells us something about the season or month in which the full Moon appears. This month's full Moon is the Harvest Moon. More about the Harvest Moon from NASA: Science 1.usa.gov/16lb1eZ Credit: NASA/Goddard/Debbie Mccallum NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Harvest Moon at NASA Goddard

NASA Image and Video Library

2013-09-20

September's Harvest Moon as seen around NASA's Goddard Space Flight Center. According to folklore, every full Moon has a special name. There's the Wolf Moon, the Snow Moon, the Worm Moon, the Sprouting Grass Moon, the Flower Moon, the Strawberry Moon, the Thunder Moon, the Sturgeon Moon, the Harvest Moon, the Hunter's Moon, the Beaver Moon, and the Long Night's Moon. Each name tells us something about the season or month in which the full Moon appears. This month's full Moon is the Harvest Moon. More about the Harvest Moon from NASA: Science 1.usa.gov/16lb1eZ Credit: NASA/Goddard/Debbie Mccallum NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

First Image from MarCO-B

NASA Image and Video Library

2018-05-15

The first image captured by one of NASA's Mars Cube One (MarCO) CubeSats. The image, which shows both the CubeSat's unfolded high-gain antenna at right and the Earth and its moon in the center, was acquired by MarCO-B on May 9. MarCO is a pair of small spacecraft accompanying NASA's InSight (Interior Investigations Using Seismic Investigations, Geodesy and Heat Transport) lander. Together, MarCO-A and MarCO-B are the first CubeSats ever sent to deep space. InSight is the first mission to ever explore Mars' deep interior. If the MarCO CubeSats make the entire journey to Mars, they will attempt to relay data about InSight back to Earth as the lander enters the Martian atmosphere and lands. MarCO will not collect any science, but are intended purely as a technology demonstration. They could serve as a pathfinder for future CubeSat missions. An annotated version is available at https://photojournal.jpl.nasa.gov/catalog/PIA22323

KSC-05PD-0147

NASA Technical Reports Server (NTRS)

2005-01-01

KENNEDY SPACE CENTER, FLA. NASA Administrator Sean OKeefe (center) is presented with a Deep Impact hat in the Press Site Auditorium following his report to employees on the state of the Agency. He is accompanied on stage by Center Director Jim Kennedy (right). The update was broadcast live via NASA Television. O'Keefe focused on the achievements of 2004 and the goals set for 2005. His remarks emphasized the milestones met in NASA's Vision for Space Exploration, including the launch of the comet-chasing Deep Impact mission and the landing of the Huygens probe on Jupiters moon Titan, both occurring in the past two days, and the progress made in meeting the requirements to return the Space Shuttle to flight. OKeefes briefing included a dialogue with Associate Administrator of NASAs Office of Exploration Systems Craig Steidle and Center Director Jim Kennedy, live; and Manager of the Space Station Office Bill Gerstenmaier and Director of Advanced Planning and Jet Propulsion Laboratory Charles Elachi, via satellite.

Transport of Ice on the Surface of Iapetus

NASA Astrophysics Data System (ADS)

Galuba, Götz G.

2014-11-01

The global black-and-white dichotomy as well as the dark floors and rims of equatorial craters on the Saturnian moon Iapetus can be explained by ice migration driven by a thermal feedback [1]. All icy moons in the Jovian and Saturnian systems are - with the exception of Titan - airless bodies. Yet it is unique, how these two types of surface features on Iapetus look. A physical model of the processes of absorption, sublimation and deposition was developed and a computational model that simulates ice migration of volatiles under these circumstances derived. The model tessellates the surfaces of an airless body into triangles of equal size that can each have different surface properties. These properties evolve while the model simulates a long-term development. A rate network of net migration is calculated from sublimation and redeposition under the assumptions ofa. a slowly rotating bodyb. undisturbed ballistic molecular trajectoriesc. isotropic emissiond. Maxwellian speed distributione. high sticking coefficients of the surfaces.The assumptions (b.) to (e.) are equally valid for all bigger outer solar system icy moons (except Titan). The very first assumption however is not equally valid throughout the moons of the outer solar system. Callisto being in many regards similar to Iapetus still has a five times higher rotation rate. So global effects depending on slow rotation are more profound on Iapetus. The computer model is complemented by a model for local ice migration from craters.First results show, that the global timescale of albedo change in our model is of the same order of magnitude as in the supporting material to [1] with a tendency towards slightly faster 2 Gyr instead of ~2.4 Gyr) darkening compared to the "Model B". The time rate of local crater darkening rates lies between the global darkening rate and rate of the opposing brightening effect as estimated in [2] to (τ between 10 and 100 MYr).[1] Formation of Iapetus’ Extreme Albedo Dichotomy by Exogenically Triggered Thermal Ice Migration, John R. Spencer , Tilmann Denk, Science 22, Vol. 327, January 2010.[2] Iapetus: Unique Surface Properties and a Global Color Dichotomy from Cassini Imaging T. Denk et al., Science 22, Vol. 327, January 2010.

The Earth's missing lead may not be in the core.

PubMed

Lagos, M; Ballhaus, C; Münker, C; Wohlgemuth-Ueberwasser, C; Berndt, J; Kuzmin, Dmitry V

2008-11-06

Relative to the CI chondrite class of meteorites (widely thought to be the 'building blocks' of the terrestrial planets), the Earth is depleted in volatile elements. For most elements this depletion is thought to be a solar nebular signature, as chondrites show depletions qualitatively similar to that of the Earth. On the other hand, as lead is a volatile element, some Pb may also have been lost after accretion. The unique (206)Pb/(204)Pb and (207)Pb/(204)Pb ratios of the Earth's mantle suggest that some lead was lost about 50 to 130 Myr after Solar System formation. This has commonly been explained by lead lost via the segregation of a sulphide melt to the Earth's core, which assumes that lead has an affinity towards sulphide. Some models, however, have reconciled the Earth's lead deficit with volatilization. Whichever model is preferred, the broad coincidence of U-Pb model ages with the age of the Moon suggests that lead loss may be related to the Moon-forming impact. Here we report partitioning experiments in metal-sulphide-silicate systems. We show that lead is neither siderophile nor chalcophile enough to explain the high U/Pb ratio of the Earth's mantle as being a result of lead pumping to the core. The Earth may have accreted from initially volatile-depleted material, some lead may have been lost to degassing following the Moon-forming giant impact, or a hidden reservoir exists in the deep mantle with lead isotope compositions complementary to upper-mantle values; it is unlikely though that the missing lead resides in the core.

Deep Space Habitat Concept of Operations for Transit Mission Phases

NASA Technical Reports Server (NTRS)

Hoffman, Stephen J.

2011-01-01

The National Aeronautics and Space Administration (NASA) has begun evaluating various mission and system components of possible implementations of what the U.S. Human Spaceflight Plans Committee (also known as the Augustine Committee) has named the flexible path (Anon., 2009). As human spaceflight missions expand further into deep space, the duration of these missions increases to the point where a dedicated crew habitat element appears necessary. There are several destinations included in this flexible path a near Earth asteroid (NEA) mission, a Phobos/Deimos (Ph/D) mission, and a Mars surface exploration mission that all include at least a portion of the total mission in which the crew spends significant periods of time (measured in months) in the deep space environment and are thus candidates for a dedicated habitat element. As one facet of a number of studies being conducted by the Human Spaceflight Architecture Team (HAT) a workshop was conducted to consider how best to define and quantify habitable volume for these future deep space missions. One conclusion reached during this workshop was the need for a description of the scope and scale of these missions and the intended uses of a habitat element. A group was set up to prepare a concept of operations document to address this need. This document describes a concept of operations for a habitat element used for these deep space missions. Although it may eventually be determined that there is significant overlap with this concept of operations and that of a habitat destined for use on planetary surfaces, such as the Moon and Mars, no such presumption is made in this document.

Education And Public Outreach For NASA's EPOXI Mission

NASA Astrophysics Data System (ADS)

McFadden, Lucy-Ann A.; Warner, E. M.; Crow, C. A.; Ristvey, J. D.; Counley, J.

2008-09-01

NASA's EPOXI mission has two scientific objectives in using the Deep Impact flyby spacecraft for further studies of comets and adding studies of extra-solar planets around other stars. During the Extrasolar Planetary Observations and Characterization (EPOCh) phase of the mission, observations of extrasolar planets transiting their parent stars are observed to further knowledge and understanding of planetary systems. Observations of Earth allow for comparison with Earth-like planets around other stars. A movie of Earth during a day when the Moon passed between Earth and the spacecraft is an educational highlight with scientific significance. The Deep Impact Extended Investigation (DIXI) continues the Deep Impact theme of investigating comets with a flyby of comet Hartley 2 in November 2010 to further explore the properties of comets and their formation. The EPOXI Education and Public Outreach (E/PO) program builds upon existing materials related to exploring comets and the Deep Impact mission, updating and modifying activities based on results from Deep Impact. An educational activity called Comparing Comets is under development that will guide students in conducting analyses similar to those that DIXI scientists will perform after observing comet Hartley 2. Existing educational materials related to planet finding from other NASA programs are linked from EPOXI's web page. Journey Through the Universe at the National Air and Space Museum encourages education in family and community groups and reaches out to underrepresented minorities. EPOXI's E/PO program additionally offers a newsletter to keep the public, teachers, and space enthusiasts apprised of mission activities. For more information visit: http://epoxi.umd.edu.

Near-IR-induced dissociation of thermally-sensitive star polymers.

PubMed

Dai, Yuqiong; Sun, Hao; Pal, Sunirmal; Zhang, Yunlu; Park, Sangwoo; Kabb, Christopher P; Wei, Wei David; Sumerlin, Brent S

2017-03-01

Responsive systems sensitive to near-infrared (NIR) light are promising for triggered release due to efficient deep tissue penetration of NIR irradiation relative to higher energy sources ( e.g. , UV), allowing for spatiotemporal control over triggering events with minimal potential for tissue damage. Herein, we report star polymers containing thermally-labile azo linkages that dissociate during conventional heating or during localized heating via the photothermal effect upon NIR irradiation. Controlled release during conventional heating was investigated for the star polymers loaded with a model dye, with negligible release being observed at 25 °C and >80% release at 90 °C. Star polymers co-loaded with NIR-responsive indocyanine green showed rapid dye release upon NIR irradiation ( λ ≥ 715 nm) due to the photothermally-induced degradation of azo linkages within the cores of the star polymers. This approach provides access to a new class of delivery and release systems that can be triggered by noninvasive external stimulation.

Oxygen, ecology, and the Cambrian radiation of animals

NASA Astrophysics Data System (ADS)

Sperling, Erik A.; Frieder, Christina A.; Raman, Akkur V.; Girguis, Peter R.; Levin, Lisa A.; Knoll, Andrew H.

2013-08-01

The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator-prey "arms races" can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation.

Submarine landslides on the north continental slope of the South China Sea

NASA Astrophysics Data System (ADS)

Wang, Weiwei; Wang, Dawei; Wu, Shiguo; Völker, David; Zeng, Hongliu; Cai, Guanqiang; Li, Qingping

2018-02-01

Recent and paleo-submarine landslides are widely distributed within strata in deep-water areas along continental slopes, uplifts, and carbonate platforms on the north continental margin of the South China Sea (SCS). In this paper, high-resolution 3D seismic data and multibeam data based on seismic sedimentology and geomorphology are employed to assist in identifying submarine landslides. In addition, deposition models are proposed that are based on specific geological structures and features, and which illustrate the local stress field over entire submarine landslides in deep-water areas of the SCS. The SCS is one of the largest fluvial sediment sinks in enclosed or semi-enclosed marginal seas worldwide. It therefore provides a set of preconditions for the formation of submarine landslides, including rapid sediment accumulation, formation of gas hydrates, and fluid overpressure. A new concept involving temporal and spatial analyses is tested to construct a relationship between submarine landslides and different time scale trigger mechanisms, and three mechanisms are discussed in the context of spatial scale and temporal frequency: evolution of slope gradient and overpressure, global environmental changes, and tectonic events. Submarine landslides that are triggered by tectonic events are the largest but occur less frequently, while submarine landslides triggered by the combination of slope gradient and over-pressure evolution are the smallest but most frequently occurring events. In summary, analysis shows that the formation of submarine landslides is a complex process involving the operation of different factors on various time scales.

Effectiveness of dry needling for chronic nonspecific neck pain: a randomized, single-blinded, clinical trial.

PubMed

Cerezo-Téllez, Ester; Torres-Lacomba, María; Fuentes-Gallardo, Isabel; Perez-Muñoz, Milagros; Mayoral-Del-Moral, Orlando; Lluch-Girbés, Enrique; Prieto-Valiente, Luis; Falla, Deborah

2016-09-01

Chronic neck pain attributed to a myofascial pain syndrome is characterized by the presence of muscle contractures referred to as myofascial trigger points. In this randomized, parallel-group, blinded, controlled clinical trial, we examined the effectiveness of deep dry needling (DDN) of myofascial trigger points in people with chronic nonspecific neck pain. The study was conducted at a public Primary Health Care Centre in Madrid, Spain, from January 2010 to December 2014. A total of 130 participants with nonspecific neck pain presenting with active myofascial trigger points in their cervical muscles were included. These participants were randomly allocated to receive: DDN plus stretching (n = 65) or stretching only (control group [n = 65]). Four sessions of treatment were applied over 2 weeks with a 6-month follow-up after treatment. Pain intensity, mechanical hyperalgesia, neck active range of motion, neck muscle strength, and perceived neck disability were measured at baseline, after 2 sessions of intervention, after the intervention period, and 15, 30, 90, and 180 days after the intervention. Significant and clinically relevant differences were found in favour of dry needling in all the outcomes (all P < 0.001) at both short and long follow-ups. Deep dry needling and passive stretching is more effective than passive stretching alone in people with nonspecific neck pain. The results support the use of DDN in the management of myofascial pain syndrome in people with chronic nonspecific neck pain.

HFT events - Shallow moonquakes. [High-Frequency Teleseismic

NASA Technical Reports Server (NTRS)

Nakamura, Y.

1977-01-01

A few large distant seismic events of distinctly high signal frequency, designated HFT (high-frequency teleseismic) events, are observed yearly by the Apollo lunar seismic network. Their sources are located on or near the surface of the moon, leaving a large gap in seismic activity between the zones of HFT sources and deep moonquakes. No strong regularities are found in either their spatial or temporal distributions. Several working hypotheses for the identity of these sources have advanced, but many characteristics of the events seem to favor a hypothesis that they are shallow moonquakes. Simultaneous observations of other lunar phenomena may eventually enable the determination of their true identity.

An overview of the Galileo Optical Experiment (GOPEX)

NASA Technical Reports Server (NTRS)

Wilson, K. E.; Lesh, J. R.

1993-01-01

Uplink optical communication to a deep-space vehicle was demonstrated. In the Galileo Optical Experiment (GOPEX), optical transmissions were beamed to the Galileo spacecraft by Earth-based transmitters at the Table Mountain Facility (TMF), California, and Starfire Optical Range (SOR), New Mexico. The demonstration took place over an eight-day period (9 Dec. through 16 Dec. 1992) as Galileo receded from Earth on its way to Jupiter, and covered ranges from 1-6 million km. At 6 million km (15 times the Earth-Moon distance), the laser beam transmitted from TMF eight days after Earth flyby covered the longest known range for transmission and detection.

Destination Deimos: A Design Reference Architecture for Initial Human Exploration of the Mars System

NASA Technical Reports Server (NTRS)

Logan, James S.; Adamo, D. R.

2011-01-01

The two biggest challenges to successful human operations in interplanetary space are flight dynamics, constrained by the cold hard physics of the rocket equation, and bioastronautics, the psychophysiological realities of human adaptation, or lack thereof, to the deep space environment. Without substantial innovation in project/mission architecture and vehicle design, human exploration of the Mars system could be problematic for decades. Although a human landing on Mars is inevitable, humans-in-the-loop telerobotic exploration from the outer Martian moon Deimos is the best way to begin. Precursor robotic missions for reconnaissance and local site preparation will be required.

North Atlantic deep water formation and AMOC in CMIP5 models

NASA Astrophysics Data System (ADS)

Heuzé, Céline; Wåhlin, Anna

2017-04-01

North Atlantic deep water formation processes and properties in climate models are indicative of their ability to simulate future ocean circulation, ventilation, carbon and heat uptake, and sea level rise. Historical time series of temperature, salinity, sea ice concentration and ocean transport in the North Atlantic subpolar gyre and Nordic Seas from 23 CMIP5 (Climate Model Intercomparison Project, phase 5) models are compared with observations to reveal the causes and consequences of North Atlantic deep water formation in models. Deep convection occurs at the sea ice edge and is most realistic in models with accurate sea ice extent, mostly those using the CICE model. The trigger of deep convection varies among models; for one third it is intense surface cooling only, while the remaining two thirds also need upward mixing of subsurface warm salty water. The models with the most intense deep convection have the most accurate deep water properties, which are warmer and fresher than in the other models. They also have the strongest Atlantic Meridional Overturning Circulation (AMOC). For over half of the models, 40% of the variability of the AMOC is explained by the volumes of deep water produced in the subpolar gyre and Nordic Seas, with 3 and 4 years lag respectively. Understanding the dynamical drivers of the AMOC in models is key to realistically forecast a possible slow down and its consequences on the global circulation and marine life.

The Tidal Triggering of Earthquakes Under Certain Circumstances

NASA Astrophysics Data System (ADS)

Goodacre, A. K.

2004-05-01

Although it would be lunacy to claim that all earthquakes are triggered by the motions of the Moon and Sun, there are certain circumstances where these celestial bodies might play a role. This would especially be the case where pre-existing, nearly vertical zones of weakness are present and, hence, the solid-earth tidal stresses would have maximum effect. I have investigated two possible areas: i) the Charlevoix seismic region of Québec along the St. Lawrence River and )ii the San Andreas and Calaveras Faults in California. In the Charlevoix region there a few suites of earthquakes, recognized by Maurice Lamontagne and lying mainly beneath or at the edge of the St. Lawrence River, in which the events in each suite occur in a relatively small volume of rock and produce similar waveforms characteristic of the particular location involved. This sort of repeated rupturing suggests the possibility of triggering by solid-earth and/or marine tides. In one sequence of 9 events (2 of which are left out of the analysis because they are aftershocks) it appears that there is only about one chance in ten that this sequence occurred at random. Unfortunately, there are no fault-plane solutions for any events in this particular set of earthquakes and so it is difficult to comment on failure mechanisms. However, in the case of the Calaveras and San Andreas Faults of California where fault-plane solutions are often available, if we restrict our attention to the larger, strike-slip earthquakes, it appears that lunar and solar tides (both solid-earth and marine) do, in fact, play a role in the timing of these events and the triggering mechanism may involve the amount of incremental normal stress acting upon these two faults.

Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

PubMed Central

Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L.; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C.; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q.; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J.; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Motz, Holger; Neff, Max; Nezri, Emma nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E.; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G.; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J. M.; Stolarczyk, Thierry; Taiuti, Mauro G. F.; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan

2013-01-01

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as “open-sea convection”. It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts. PMID:23874425

Global Search of Triggered Tectonic Tremor

NASA Astrophysics Data System (ADS)

Peng, Z.; Aiken, C.; Chao, K.; Gonzalez-Huizar, H.; Wang, B.; Ojha, L.; Yang, H.

2013-05-01

Deep tectonic tremor has been observed at major plate-boundary faults around the Pacific Rim. While regular or ambient tremor occurs spontaneously or accompanies slow-slip events, tremor could be also triggered by large distant earthquakes and solid earth tides. Because triggered tremor occurs on the same fault patches as ambient tremor and is relatively easy to identify, a systematic global search of triggered tremor could help to identify the physical mechanisms and necessary conditions for tremor generation. Here we conduct a global search of tremor triggered by large teleseismic earthquakes. We mainly focus on major faults with significant strain accumulations where no tremor has been reported before. These includes subduction zones in Central and South America, strike-slip faults around the Caribbean plate, the Queen Charlotte-Fairweather fault system and the Denali fault in the western Canada and Alaska, the Sumatra-Java subduction zone, the Himalaya frontal thrust faults, as well as major strike-slip faults around Tibet. In each region, we first compute the predicted dynamic stresses σd from global earthquakes with magnitude>=5.0 in the past 20 years, and select events with σd > 1 kPa. Next, we download seismic data recorded by stations from local or global seismic networks, and identify triggered tremor as a high-frequency non-impulsive signal that is in phase with the large-amplitude teleseismic waves. In cases where station distributions are dense enough, we also locate tremor based on the standard envelope cross-correlation techniques. Finally, we calculate the triggering potential for the Love and Rayleigh waves with the local fault orientation and surface-wave incident angles. So far we have found several new places that are capable of generating triggered tremor. We will summarize these observations and discuss their implications on physical mechanisms of tremor and remote triggering.

Tremor, remote triggering and earthquake cycle

NASA Astrophysics Data System (ADS)

Peng, Z.

2012-12-01

Deep tectonic tremor and episodic slow-slip events have been observed at major plate-boundary faults around the Pacific Rim. These events have much longer source durations than regular earthquakes, and are generally located near or below the seismogenic zone where regular earthquakes occur. Tremor and slow-slip events appear to be extremely stress sensitive, and could be instantaneously triggered by distant earthquakes and solid earth tides. However, many important questions remain open. For example, it is still not clear what are the necessary conditions for tremor generation, and how remote triggering could affect large earthquake cycle. Here I report a global search of tremor triggered by recent large teleseismic earthquakes. We mainly focus on major subduction zones around the Pacific Rim. These include the southwest and northeast Japan subduction zones, the Hikurangi subduction zone in New Zealand, the Cascadia subduction zone, and the major subduction zones in Central and South America. In addition, we examine major strike-slip faults around the Caribbean plate, the Queen Charlotte fault in northern Pacific Northwest Coast, and the San Andreas fault system in California. In each place, we first identify triggered tremor as a high-frequency non-impulsive signal that is in phase with the large-amplitude teleseismic waves. We also calculate the dynamic stress and check the triggering relationship with the Love and Rayleigh waves. Finally, we calculate the triggering potential with the local fault orientation and surface-wave incident angles. Our results suggest that tremor exists at many plate-boundary faults in different tectonic environments, and could be triggered by dynamic stress as low as a few kPas. In addition, we summarize recent observations of slow-slip events and earthquake swarms triggered by large distant earthquakes. Finally, we propose several mechanisms that could explain apparent clustering of large earthquakes around the world.

Contemplative Janus

NASA Image and Video Library

2015-01-19

Janus (111 miles or 179 kilometers across) seems to almost stare off into the distance, contemplating deep, moonish thoughts as the F ring stands by at the bottom of this image. From this image, it is easy to distinguish Janus' shape from that of a sphere. Many of Saturn's smaller moons have similarly irregular shapes that scientists believe may give clues to their origins and internal structure. Models combining the dynamics of this moon with its shape imply the existence of mass inhomogeneities within Janus. This would be a surprising result for a body the size of Janus. By studying more images of Janus, scientists may be able confirm this finding and determine just how complicated the internal structure of this small body is. This image is roughly centered on the side of Janus which faces away from Saturn. North on Janus is up and rotated 3 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 28, 2012. The view was obtained at a distance of approximately 54,000 miles (87,000 kilometers) from Janus. Image scale is 1,700 feet (520 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA18299

A history of the Lonar crater, India: An overview

NASA Technical Reports Server (NTRS)

Nayak, V. K.

1992-01-01

The origin of the circular structure at Lonar, India, described variously as cauldron, pit, hollow, depression, and crater, has been a controversial subject since the early nineteenth century. A history of its origin and other aspects from 1823 to 1990 are overviewed. The structure in the Deccan Trap Basalt is nearly circular with a breach in the northeast, 1830 m in diameter, 150 m deep, with a saline lake in the crater floor. Over the years, the origin of the Lonar structure has risen from volcanism, subsidence, and cryptovolcanism to an authentic meteorite impact crater. Lonar is unique because it is probably the only terrestrial crater in basalt and is the closest analog with the Moon's craters. Some unresolved questions are suggested. The proposal is made that the young Lonar impact crater, which is less than 50,000 years old, should be considered as the best crater laboratory analogous to those of the Moon, be treated as a global monument, and preserved for scientists to comprehend more about the mysteries of nature and impact cratering, which is now emerging as a fundamental ubiquitous geological process in the evolution of the planets.

Saturn Apollo Program

NASA Image and Video Library

1971-07-31

This is a photo of the Apollo 15 Lunar Module, Falcon, on the lunar surface. Apollo 15 launched from Kennedy Space Center (KSC) on July 26, 1971 via a Saturn V launch vehicle. Aboard was a crew of three astronauts including David R. Scott, Mission Commander; James B. Irwin, Lunar Module Pilot; and Alfred M. Worden, Command Module Pilot. The first mission designed to explore the Moon over longer periods, greater ranges and with more instruments for the collection of scientific data than on previous missions, the mission included the introduction of a $40,000,000 lunar roving vehicle (LRV) that reached a top speed of 16 kph (10 mph) across the Moon's surface. The successful Apollo 15 lunar landing mission was the first in a series of three advanced missions planned for the Apollo program. The primary scientific objectives were to observe the lunar surface, survey and sample material and surface features in a preselected area of the Hadley-Apennine region, setup and activation of surface experiments and conduct in-flight experiments and photographic tasks from lunar orbit. Apollo 15 televised the first lunar liftoff and recorded a walk in deep space by Alfred Worden. Both the Saturn V rocket and the LRV were developed at the Marshall Space Flight Center.

Foundation, excavation and radiation shielding concepts for a 16-m large lunar telescope

NASA Technical Reports Server (NTRS)

Chua, Koon M.; Johnson, Stewart W.

1991-01-01

NASA is considering a 16-m diameter optical telescope on the moon as a part of the Space Exploration Initiative. Fundamental concepts of engineering activities on the moon and how they can be applied to the establishment of a 16-m large lunar telescope (LLT) are discussed. These fundamental concepts include the engineering response of lunar soils and how they affect construction activities, namely, drilling, blasting, ripping, digging and compaction. A mirror support structure and foundation design concept is proposed. The foundation considered is a multiple contact points spud-can type footing. It does not appear that a deep foundation or the presence of bedrock is required to achieve the telescope foundation stiffness. The LLT system will include a regolith covered housing, the size of a small room, which will contain sensitive electronic equipment including charge coupled devices which need protection from cosmic radiation effects. A brief discussion is made on radiation, radiation transport and radiation effects on electronics and on humans. Radiation protection techniques and the different emplacement schemes for the LLT instrument housing for radiation protection are suggested. A structural concept of an early lunar based telescope is also presented.

Interactive Exploration Robots: Human-Robotic Collaboration and Interactions

NASA Technical Reports Server (NTRS)

Fong, Terry

2017-01-01

For decades, NASA has employed different operational approaches for human and robotic missions. Human spaceflight missions to the Moon and in low Earth orbit have relied upon near-continuous communication with minimal time delays. During these missions, astronauts and mission control communicate interactively to perform tasks and resolve problems in real-time. In contrast, deep-space robotic missions are designed for operations in the presence of significant communication delay - from tens of minutes to hours. Consequently, robotic missions typically employ meticulously scripted and validated command sequences that are intermittently uplinked to the robot for independent execution over long periods. Over the next few years, however, we will see increasing use of robots that blend these two operational approaches. These interactive exploration robots will be remotely operated by humans on Earth or from a spacecraft. These robots will be used to support astronauts on the International Space Station (ISS), to conduct new missions to the Moon, and potentially to enable remote exploration of planetary surfaces in real-time. In this talk, I will discuss the technical challenges associated with building and operating robots in this manner, along with lessons learned from research conducted with the ISS and in the field.

Integrated Attitude Control Strategy for the Asteroid Redirect Mission

NASA Technical Reports Server (NTRS)

Lopez, Pedro, Jr.; Price, Hoppy; San Martin, Miguel

2014-01-01

A deep-space mission has been proposed to redirect an asteroid to a distant retrograde orbit around the moon using a robotic vehicle, the Asteroid Redirect Vehicle (ARV). In this orbit, astronauts will rendezvous with the ARV using the Orion spacecraft. The integrated attitude control concept that Orion will use for approach and docking and for mated operations will be described. Details of the ARV's attitude control system and its associated constraints for redirecting the asteroid to the distant retrograde orbit around the moon will be provided. Once Orion is docked to the ARV, an overall description of the mated stack attitude during all phases of the mission will be presented using a coordinate system that was developed for this mission. Next, the thermal and power constraints of both the ARV and Orion will be discussed as well as how they are used to define the optimal integrated stack attitude. Lastly, the lighting and communications constraints necessary for the crew's extravehicular activity planned to retrieve samples from the asteroid will be examined. Similarly, the joint attitude control strategy that employs both the Orion and the ARV attitude control assets prior, during, and after each extravehicular activity will also be thoroughly discussed.

Rosetta performs ESA's closest-ever Earth fly-by

NASA Astrophysics Data System (ADS)

2005-03-01

The passage through the Earth-Moon system allowed ground controllers to test Rosetta's 'asteroid fly-by mode' (AFM) using the Moon as a 'fake' asteroid, rehearsing the fly-bys of asteroids Steins and Lutetia due in 2008 and 2010 respectively. The AFM test started at 23:01 GMT and ran for nine minutes during which the two onboard navigation cameras successfully tracked the Moon, allowing Rosetta's attitude to be automatically adjusted. Before and after closest approach, the navigation cameras also acquired a series of images of the Moon and Earth; these data will be downloaded early today for ground processing and are expected to be available by 8 March. In addition, other onboard instruments were switched on, including ALICE (ultraviolet imaging spectrometer), VIRTIS (visible and infrared mapping spectrometer) and MIRO (microwave instrument for the Rosetta orbiter), for calibration and general testing using the Earth and Moon as targets. The fly-by manoeuvre swung the three-tonne spacecraft around our planet and out towards Mars, where it will make a fly-by on 26 February 2007. Rosetta will return to Earth again in a series of four planet fly-bys (three times with Earth, once with Mars) before reaching Comet 67P/Churyumov-Gerasimenko in 2014, when it will enter orbit and deliver a lander, Philae, onto the surface. The fly-bys are necessary to accelerate the spacecraft so as to eventually match the velocity of the target comet. They are a fuel-saving way to boost speed using planetary gravity. Yesterday's fly-by came one year and two days after launch and highlights the valuable opportunities for instrument calibration and data gathering available during the mission's multi-year voyage. In just three months, on 4 July, Rosetta will be in a good position to observe and gather data during NASA's spectacular Deep Impact event, when the Deep Impact probe will hurl a 380 kg projectile into Comet Tempel 1, revealing data on the comet's internal structure. Certain of Rosetta’s unique instruments, such as its ultraviolet light instrument ALICE, should be able to make critical contributions to the American mission. About Rosetta Rosetta is the first mission designed to both orbit and land on a comet, and consists of an orbiter and a lander. The spacecraft carries 11 scientific experiments and will be the first mission to undertake long-term exploration of a comet at close quarters. After entering orbit around Comet 67P/Churyumov-Gerasimenko in 2014, the spacecraft will release a small lander onto the icy nucleus. Rosetta will orbit the comet for about a year as it heads towards the Sun, remaining in orbit for another half-year past perihelion (closest approach to the Sun). Comets hold essential information about the origin of our Solar System because they are the most primitive objects in the Solar System and their chemical composition has changed little since their formation. By orbiting and landing on Comet 67P/Churyumov-Gerasimenko, Rosetta will help us reconstruct the history of our own neighbourhood in space. Note for broadcasters: The ESA TV Service will transmit a TV exchange with images of the fly-by, together with science results/images from observations as far as available on 11 March. For further details : http://television.esa.int

Ganymede and Europa and their Jovian polar footprints

NASA Astrophysics Data System (ADS)

Sejkora, N.; Rucker, H. O.; Panchenko, M.

2017-09-01

The interactions between the Galilean moons Europa and Ganymede and the Jovian magnetosphere are studied. The focus lies on the satellites' auroral footprints observable in the polar regions of Jupiter. The work encompasses case studies of UV observations, obtained by the Hubble Space Telescope (HST), showing auroral features potentially triggered by either Europa or Ganymede. For those situations the footprint lead angles are determined, using different magnetic field models. The aim is to estimate the relationship between satellite longitude and lead angle. The delay between the local interaction at the satellite and the resulting auroral emission, which is implied by the obtained lead angles, is compared to the travel time of an Alfvén wave along a magnetic field line from the satellite to the planet.

Exchange processes from the deep interior to the surface of icy moons

NASA Astrophysics Data System (ADS)

Grasset, O.

Space exploration provides outstanding images of planetary surfaces. Galileo space- craft around Jupiter, and now Cassini in the saturnian system have revealed to us the variety of icy surfaces in the solar system. While Europa, Enceladus, and maybe Titan present past or even active tectonic and volcanic activities, many other moons have been dead worlds for more than 3 billions years. Composition of ices is also complex and it is now commonly admitted that icy surfaces are never composed of pure ices. Water ice can be mixed with salts (Europa?), with hydrocarbons (Titan?) or with silicates (Callisto). The present surfaces of icy moons are the results of both internal (tectonic; volcanism; mantle composition; magnetic field; . . . ) and external processes (radiations, atmospheres, impacts, . . . ). Internal activity (past or present) is almost unknown. While the surfaces indicate clearly that an important activity existed (Ganymede, Europa, Titan, . . . ) or still exists (Enceladus, Titan?, . . . ), volcanic and tectonic processes within icy mantles are still very poorly understood. This project proposes some key studies for improving our knowledge of exchange processes within icy moons, which are: 1) Surface compositions: Interpretation of mapping spectrometer data. It addresses the interpretation of remote sensing data. These data are difficult to understand and a debate between people involved in Galileo and those who are now trying to interpret Cassini data might be fruitful. As an example, interpretation of Galileo data on Europa are still controversial. It is impossible to affirm that the "non-icy" material which does not present the classic infrared signature of pure ice is due to the presence of magnesium hydrates, sodium hydrates, magnesium sulfurs, "clays", or even altered water ice. Discussion on the subject are still needed. On Titan, the presence of the atmosphere impedes to link IR data from Cassini to the composition of the surface. 2) Past and present dynamics of icy surfaces: erosion, tectonics and cryovolcanism. This second topic is devoted to the description of the surface features. A synthesis of what has been seen in the jovian system and a presentation of what is now discovered in the saturnian system might be useful. 3) Internal processes: dynamics of icy mantles. Many works have been done specifically for icy moons (rheology of icy mantles, heating modes, effect of ice composition, internal activity of small moons, internal oceans,. . . ). Icy mantles present so many different convective processes, depending on parameters such as the ice composition, the heating mode, . . . , that a full review of the recent progress on the subject is required. 4) Physics and chemistry of ices: experimental constraints on hydrates, clathrates and organics. Nothing can be done without experimental data. Thermodynamical constraints, phase diagrams, but also mechanical properties of icy materials are required for constraining all models. Many progress have been made these last five years, especially for clathrate structures so important in the case of Titan. A review of these progresses is required. 5) Earth analogs: a tool for understanding surface/ internal features. Tectonic and volcanic features on icy moons are sometimes confronted to Earth structures. This procedure is very interesting. While materials are different (on Earth the melt is lighter than the rock, but on icy moons it is the contrary), tectonic and volcanic features can be very similar. Our good understanding of the Earth can be very useful for describing the processes responsible of tectonic/volcanic features on the moons. Discussing around the five themes described above may provide some constraints on open questions such as the characteristics of liquid layers within icy moons, the cryovolcanism on Titan, the resurfacing of Europa, the composition of Titan's surface, and the activity on Enceladus. 2

Astrobiological Significance of Microbial Extremophiles

NASA Technical Reports Server (NTRS)

Pikuta, Elena V.; Hoover, Richard B.

2007-01-01

The microflora of the cryosphere of planet Earth provides the best analogs for life forms that might be found in the permafrost or polar ice caps of Mars, near the surface of the cometary nuclei, or in the liquid water beneath and the ice crusts of icy moons of Jupiter and Saturn. The importance of study alkaliphilic microorganisms for astrobiology was enhanced by the findings of abundant carbonates and carbonate globules rimmed with possibly biogenic magnetites in association with the putative microfossils in the ALH84001 meteorite. Although the ALH84001 "nanofossils" were to small and simple to be unambiguously recognized as biogenic, they stimulated Astrobiology research and studies of microbial extremophiles and biomarkers in ancient rocks and meteorites. Recent studies of CI and CM carbonaceous meteorites have resulted in the detection of the well-preserved mineralized remains of coccoidal and filamentous microorganisms in cyanobacterial mats. Energy Dispersive X-ray Analysis has shown anomalous biogenic element ratios clearly indicating they are not recent biological contaminants. This paper reviews microbial extremophiles in context of their significance to Astrobiology. The study of halophilic microorganisms was started from work with saline soils and lakes, and one of the record of good growth for Haloferax mediterranei was shown at 30 percent NaC1. Although alkali-tolerant nitrifying bacteria had previously been reported, the first described alkaliphilic microorganism was the bacterium Streptococcus faecalis. Halophilic and alkaliphilic forms are relevant to conditions that might be found in closed impact basins and craters on Mars filled with evaporite deposits. The first obligately acidophilic bacterium described was Acidithiobacillus ferrooxydans (formally Thiobacillus ferrooxidans). Later thermophilic lithotrophic acidophiles were found, and the hyperacidophilic moderately thermophilic species of the genus Picrophilus were found to grow at negative pH. The epoch of study of thermophilic microorganisms starts with the discovery of Thermus aquaticus, and presently the maximum temperature for growth at 113 C was found for Pyrolobus fumarii. The microorganisms capable of growth at high temperatures and in hyperacidic environments on Earth are good analogs for life that might be able to survive in hot acidic droplets in the upper regimes of the atmosphere of Venus. The study of barophiles was made possible by engineering achievements leading to the development of the submersible crafts used to study the Black Smokers of the Deep-sea Hydrothermal vents. The first described radioresistant bacterium Deinococcus radiodurans can survive ionizing irradiation and other DNA-damaging assaults at doses that are lethal to all other organisms. These microbes are models for life that might endure high radiation environments in the ice near the surface of comets or on the icy moons of Jupiter and Saturn and in the seafloor deep beneath icy crusts Europa and Enceladus. This paper presents ESEM and FESEM images showing intact microbes preserved in the deep ice cores extracted from just above Lake Vostok, Antarctica that are considered analogs for life forms that might survive on comets and icy moons.

Space Radiation Risk Assessment

NASA Astrophysics Data System (ADS)

Blakely, E.

Evaluation of potential health effects from radiation exposure during and after deep space travel is important for the future of manned missions To date manned missions have been limited to near-Earth orbits with the moon our farthest distance from earth Historical space radiation career exposures for astronauts from all NASA Missions show that early missions involved total exposures of less than about 20 mSv With the advent of Skylab and Mir total career exposure levels increased to a maximum of nearly 200 mSv Missions in deep space with the requisite longer duration of the missions planned may pose greater risks due to the increased potential for exposure to complex radiation fields comprised of a broad range of radiation types and energies from cosmic and unpredictable solar sources The first steps in the evaluation of risks are underway with bio- and physical-dosimetric measurements on both commercial flight personnel and international space crews who have experience on near-earth orbits and the necessary theoretical modeling of particle-track traversal per cell including the contributing effects of delta-rays in particle exposures An assumption for biologic effects due to exposure of radiation in deep space is that they differ quantitatively and qualitatively from that on earth The dose deposition and density pattern of heavy charged particles are very different from those of sparsely ionizing radiation The potential risks resulting from exposure to radiation in deep space are cancer non-cancer and genetic effects Radiation from

Apollo Lunar Astronauts Show Higher Cardiovascular Disease Mortality: Possible Deep Space Radiation Effects on the Vascular Endothelium

PubMed Central

Delp, Michael D.; Charvat, Jacqueline M.; Limoli, Charles L.; Globus, Ruth K.; Ghosh, Payal

2016-01-01

As multiple spacefaring nations contemplate extended manned missions to Mars and the Moon, health risks could be elevated as travel goes beyond the Earth’s protective magnetosphere into the more intense deep space radiation environment. The primary purpose of this study was to determine whether mortality rates due to cardiovascular disease (CVD), cancer, accidents and all other causes of death differ in (1) astronauts who never flew orbital missions in space, (2) astronauts who flew only in low Earth orbit (LEO), and (3) Apollo lunar astronauts, the only humans to have traveled beyond Earth’s magnetosphere. Results show there were no differences in CVD mortality rate between non-flight (9%) and LEO (11%) astronauts. However, the CVD mortality rate among Apollo lunar astronauts (43%) was 4–5 times higher than in non-flight and LEO astronauts. To test a possible mechanistic basis for these findings, a secondary purpose was to determine the long-term effects of simulated weightlessness and space-relevant total-body irradiation on vascular responsiveness in mice. The results demonstrate that space-relevant irradiation induces a sustained vascular endothelial cell dysfunction. Such impairment is known to lead to occlusive artery disease, and may be an important risk factor for CVD among astronauts exposed to deep space radiation. PMID:27467019

Optimization Shield Materials Trade Study for Lunar/Gateway Mission

NASA Technical Reports Server (NTRS)

Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.; Anderson, B. M.; Simonsen, L. C.

2002-01-01

The great cost of added radiation shielding is a potential limiting factor in many deep space missions. For this enabling technology, we are developing tools for optimized shield design over multi-segmented missions involving multiple work and living areas in the transport and duty phase of various space missions. The total shield mass over all pieces of equipment and habitats is optimized subject to career dose and dose rate constraints. Preliminary studies of deep space missions indicate that for long duration space missions, improved shield materials will be required. The details of this new method and its impact on space missions and other technologies will be discussed. This study will provide a vital tool for evaluating Gateway designs in their usage context. Providing protection against the hazards of space radiation is one of the challenges to the Gateway infrastructure designs. We will use the mission optimization software to scope the impact of Gateway operations on human exposures and the effectiveness of alternate shielding materials on Gateway infrastructure designs. It is being proposed to use Moon and the Lagrange points as the hub for deep space missions. This study will provide a guide to the effectiveness of multifunctional materials in preparation to more detailed geometry studies in progress.

Apollo Lunar Astronauts Show Higher Cardiovascular Disease Mortality: Possible Deep Space Radiation Effects on the Vascular Endothelium.

PubMed

Delp, Michael D; Charvat, Jacqueline M; Limoli, Charles L; Globus, Ruth K; Ghosh, Payal

2016-07-28

As multiple spacefaring nations contemplate extended manned missions to Mars and the Moon, health risks could be elevated as travel goes beyond the Earth's protective magnetosphere into the more intense deep space radiation environment. The primary purpose of this study was to determine whether mortality rates due to cardiovascular disease (CVD), cancer, accidents and all other causes of death differ in (1) astronauts who never flew orbital missions in space, (2) astronauts who flew only in low Earth orbit (LEO), and (3) Apollo lunar astronauts, the only humans to have traveled beyond Earth's magnetosphere. Results show there were no differences in CVD mortality rate between non-flight (9%) and LEO (11%) astronauts. However, the CVD mortality rate among Apollo lunar astronauts (43%) was 4-5 times higher than in non-flight and LEO astronauts. To test a possible mechanistic basis for these findings, a secondary purpose was to determine the long-term effects of simulated weightlessness and space-relevant total-body irradiation on vascular responsiveness in mice. The results demonstrate that space-relevant irradiation induces a sustained vascular endothelial cell dysfunction. Such impairment is known to lead to occlusive artery disease, and may be an important risk factor for CVD among astronauts exposed to deep space radiation.

Deep geothermal systems interpreted by coupled thermo-hydraulic-mechanical-chemical numerical modeling

NASA Astrophysics Data System (ADS)

Peters, Max; Lesueur, Martin; Held, Sebastian; Poulet, Thomas; Veveakis, Manolis; Regenauer-Lieb, Klaus; Kohl, Thomas

2017-04-01

The dynamic response of the geothermal reservoirs of Soultz-sous-Forêts (NE France) and a new site in Iceland are theoretically studied upon fluid injection and production. Since the Soultz case can be considered the most comprehensive project in the area of enhanced geothermal systems (EGS), it is tailored for the testing of forward modeling techniques that aim at the characterization of fluid dynamics and mechanical properties in any deeply-seated fractured cystalline reservoir [e.g. Held et al., 2014]. We present multi-physics finite element models using the recently developed framework MOOSE (mooseframework.org) that implicitly consider fully-coupled feedback mechanisms of fluid-rock interaction at depth where EGS are located (depth > 5 km), i.e. the effects of dissipative strain softening on chemical reactions and reactive transport [Poulet et al., 2016]. In a first suite of numerical experiments, we show that an accurate simulation of propagation fronts allows studying coupled fluid and heat transport, following preferred pathways, and the transport time of the geothermal fluid between injection and production wells, which is in good agreement with tracer experiments performed inside the natural reservoir. Based on induced seismicity experiments and related damage along boreholes, we concern with borehole instabilities resulting from pore pressure variations and (a)seismic creep in a second series of simulations. To this end, we account for volumetric and deviatoric components, following the approach of Veveakis et al. (2016), and discuss the mechanisms triggering slow earthquakes in the stimulated reservoirs. Our study will allow applying concepts of unconventional geomechanics, which were previously reviewed on a theoretical basis [Regenauer-Lieb et al., 2015], to substantial engineering problems of deep geothermal reservoirs in the future. REFERENCES Held, S., Genter, A., Kohl, T., Kölbel, T., Sausse, J. and Schoenball, M. (2014). Economic evaluation of geothermal reservoir performance through modeling the complexity of the operating EGS in Soultz-sous-Forêts. Geothermics, 51, 270-280, doi:10.1016/j.geothermics.2014.01.016 Poulet, T., Paesold, M. and Veveakis, M. (2016). Multi-Physics Modelling of Fault Mechanics Using REDBACK: A Parallel Open-Source Simulator for Tightly Coupled Problems. Rock Mechanics and Rock Engineering, doi:10.1007/s00603-016-0927-y Regenauer-Lieb, K., Bunger, A., Chua, H. T., et al., 2015. Deep Geothermal: The 'Moon Landing' Mission in the Unconventional Energy and Minerals Space. Journal of Earth Science, 26(1): 2-10, doi:10.1007/s12583-015-0515-1 Veveakis, M., Alevizos, S., Poulet, T. (2016). Episodic Tremor and Slip (ETS) as a chaotic Multiphysics spring. Physics of the Earth and Planetary Interiors, in press, doi:10.1016/j.pepi.2016.10.002

Effects of hydrostatic pressure on yeasts isolated from deep-sea hydrothermal vents.

PubMed

Burgaud, Gaëtan; Hué, Nguyen Thi Minh; Arzur, Danielle; Coton, Monika; Perrier-Cornet, Jean-Marie; Jebbar, Mohamed; Barbier, Georges

2015-11-01

Hydrostatic pressure plays a significant role in the distribution of life in the biosphere. Knowledge of deep-sea piezotolerant and (hyper)piezophilic bacteria and archaea diversity has been well documented, along with their specific adaptations to cope with high hydrostatic pressure (HHP). Recent investigations of deep-sea microbial community compositions have shown unexpected micro-eukaryotic communities, mainly dominated by fungi. Molecular methods such as next-generation sequencing have been used for SSU rRNA gene sequencing to reveal fungal taxa. Currently, a difficult but fascinating challenge for marine mycologists is to create deep-sea marine fungus culture collections and assess their ability to cope with pressure. Indeed, although there is no universal genetic marker for piezoresistance, physiological analyses provide concrete relevant data for estimating their adaptations and understanding the role of fungal communities in the abyss. The present study investigated morphological and physiological responses of fungi to HHP using a collection of deep-sea yeasts as a model. The aim was to determine whether deep-sea yeasts were able to tolerate different HHP and if they were metabolically active. Here we report an unexpected taxonomic-based dichotomic response to pressure with piezosensitve ascomycetes and piezotolerant basidiomycetes, and distinct morphological switches triggered by pressure for certain strains. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Quantifying the influence of deep soil moisture on ecosystem albedo: The role of vegetation

NASA Astrophysics Data System (ADS)

Sanchez-Mejia, Zulia Mayari; Papuga, Shirley Anne; Swetish, Jessica Blaine; van Leeuwen, Willem Jan Dirk; Szutu, Daphne; Hartfield, Kyle

2014-05-01

As changes in precipitation dynamics continue to alter the water availability in dryland ecosystems, understanding the feedbacks between the vegetation and the hydrologic cycle and their influence on the climate system is critically important. We designed a field campaign to examine the influence of two-layer soil moisture control on bare and canopy albedo dynamics in a semiarid shrubland ecosystem. We conducted this campaign during 2011 and 2012 within the tower footprint of the Santa Rita Creosote Ameriflux site. Albedo field measurements fell into one of four Cases within a two-layer soil moisture framework based on permutations of whether the shallow and deep soil layers were wet or dry. Using these Cases, we identified differences in how shallow and deep soil moisture influence canopy and bare albedo. Then, by varying the number of canopy and bare patches within a gridded framework, we explore the influence of vegetation and soil moisture on ecosystem albedo. Our results highlight the importance of deep soil moisture in land surface-atmosphere interactions through its influence on aboveground vegetation characteristics. For instance, we show how green-up of the vegetation is triggered by deep soil moisture, and link deep soil moisture to a decrease in canopy albedo. Understanding relationships between vegetation and deep soil moisture will provide important insights into feedbacks between the hydrologic cycle and the climate system.

A multiple distributed representation method based on neural network for biomedical event extraction.

PubMed

Wang, Anran; Wang, Jian; Lin, Hongfei; Zhang, Jianhai; Yang, Zhihao; Xu, Kan

2017-12-20

Biomedical event extraction is one of the most frontier domains in biomedical research. The two main subtasks of biomedical event extraction are trigger identification and arguments detection which can both be considered as classification problems. However, traditional state-of-the-art methods are based on support vector machine (SVM) with massive manually designed one-hot represented features, which require enormous work but lack semantic relation among words. In this paper, we propose a multiple distributed representation method for biomedical event extraction. The method combines context consisting of dependency-based word embedding, and task-based features represented in a distributed way as the input of deep learning models to train deep learning models. Finally, we used softmax classifier to label the example candidates. The experimental results on Multi-Level Event Extraction (MLEE) corpus show higher F-scores of 77.97% in trigger identification and 58.31% in overall compared to the state-of-the-art SVM method. Our distributed representation method for biomedical event extraction avoids the problems of semantic gap and dimension disaster from traditional one-hot representation methods. The promising results demonstrate that our proposed method is effective for biomedical event extraction.

Degassing during quiescence as a trigger of magma ascent and volcanic eruptions.

PubMed

Girona, Társilo; Costa, Fidel; Schubert, Gerald

2015-12-15

Understanding the mechanisms that control the start-up of volcanic unrest is crucial to improve the forecasting of eruptions at active volcanoes. Among the most active volcanoes in the world are the so-called persistently degassing ones (e.g., Etna, Italy; Merapi, Indonesia), which emit massive amounts of gas during quiescence (several kilotonnes per day) and erupt every few months or years. The hyperactivity of these volcanoes results from frequent pressurizations of the shallow magma plumbing system, which in most cases are thought to occur by the ascent of magma from deep to shallow reservoirs. However, the driving force that causes magma ascent from depth remains unknown. Here we demonstrate that magma ascent can be triggered by the passive release of gas during quiescence, which induces the opening of pathways connecting deep and shallow magma reservoirs. This top-down mechanism for volcanic eruptions contrasts with the more common bottom-up mechanisms in which magma ascent is only driven by processes occurring at depth. A cause-effect relationship between passive degassing and magma ascent can explain the fact that repose times are typically much longer than unrest times preceding eruptions, and may account for the so frequent unrest episodes of persistently degassing volcanoes.

Effects of Orbital Evolution on Lunar Ice Stability

NASA Astrophysics Data System (ADS)

Siegler, M. A.; Bills, B. G.; Paige, D. A.

2010-12-01

Permanently shadowed regions of the Moon have complex thermal histories that influence their ability to act as traps for water ice. Though many areas are now cold enough that surface water ice would be stable from sublimation losses for billions of years, this has not always been the case. Here we examine the effects of the long term orbital and rotational evolution of the Moon on polar thermal history, volatile stability and mobility. Using data from the Diviner Lunar Radiometer, aboard the Lunar Reconnaissance Orbiter, we validate models of the current temperature in the lunar polar region. This model includes the effects of topography, scattering, re-radiation, and regolith thermal properties. Then, integrating the effects of tidal torques backward from the present, we reconstruct past orbital and rotational states and use them as input to the thermal model to estimate the thermal environment of the distant lunar past. The rate of tidal evolution of the lunar orbit is quite uncertain, thus use orbital semimajor axis as independent variable, rather than time, in the reconstruction. The orbital integration results in a high obliquity period which occurred when the Moon was at about half its present distance from the Earth. This period, which caused half a year of direct sunlight on the polar region, is due to a transition between two Cassini States, spin-orbit configurations resulting from internal dissipation within the Moon. Since this event, the tilt of the Moon (with respect to the ecliptic) has slowly decreased to the current 1.54 degree. Prior to this transition, due to the relatively small Earth-Moon distance, large amplitude variations in the inclination of the orbital plain were also important. We examine the stability of polar volatiles in response to the evolving lunar orbit, and apply simple models to describe when in the Moon’s history supplied volatiles would have been most likely to be buried by thermal diffusion. When temperatures are much below 95K, ice delivered to the lunar surface is immobile in terms of thermal diffusion. Unless buried on relatively short time scales, most of the current polar environments are currently too cold to efficiently drive ice downward along thermal gradients and protect it from other surface loss processes. In the past, these same locations went through “ice trap” periods, where they were warm enough that supplied volatiles might have been buried by on short time scales, but cold enough that they would not be lost quickly, supplying the subsurface with volatiles that could still be stable today. The Cassini state transition was so warm that ice would either have been driven out into space, or possibly deep into the lunar subsurface. If a present lunar cold trap is ice bearing, that ice is likely to be representative of these “ice trap” periods and have little to do with the early Moon. As each current cold trap had a period where it was most efficient at thermal ice burial, the location of current ground ice on the Moon might also constrain the obliquity and time at which it was deposited. The presence of ice in a specific crater may imply either an increase in water flux or large comet impact during that period.

Supershear rupture in the 24 May 2013 Mw 6.7 Okhotsk deep earthquake: Additional evidence from regional seismic stations

NASA Astrophysics Data System (ADS)

Zhan, Zhongwen; Shearer, Peter M.; Kanamori, Hiroo

2015-10-01

Zhan et al. (2014a) reported supershear rupture during the Mw 6.7 aftershock of the 2013 Mw 8.3 Sea of Okhotsk deep earthquake, relying heavily on the regional station PET, which played a critical role in constraining the vertical rupture dimension and rupture speed. Here we include five more regional stations and find that the durations of the source time functions derived from these stations are consistent with Zhan et al.'s supershear rupture model. Furthermore, to reduce the nonuniqueness of deconvolution and combine the bandwidths of different stations, we conduct a joint inversion of the six regional stations for a single broadband moment-rate function (MRF). The best fitting MRF, which explains all the regional waveforms well, has a smooth shape without any temporal gaps. The Mw 6.7 Okhotsk deep earthquake is more likely a continuous supershear rupture than a dynamically triggered doublet.

Sudden deep gas eruption nearby Rome's airport of Fiumicino

NASA Astrophysics Data System (ADS)

Ciotoli, Giancarlo; Etiope, Giuseppe; Florindo, Fabio; Marra, Fabrizio; Ruggiero, Livio; Sauer, Peter E.

2013-11-01

24 August 2013 a sudden gas eruption from the ground occurred in the Tiber river delta, nearby Rome's international airport of Fiumicino. We assessed that this gas, analogous to other minor vents in the area, is dominantly composed of deep, partially mantle-derived CO2, as in the geothermal gas of the surrounding Roman Comagmatic Province. Increased amounts of thermogenic CH4 are likely sourced from Meso-Cenozoic petroleum systems, overlying the deep magmatic fluids. We hypothesize that the intersection of NE-SW and N-S fault systems, which at regional scale controls the location of the Roman volcanic edifices, favors gas uprising through the impermeable Pliocene and deltaic Holocene covers. Pressurized gas may temporarily be stored below these covers or within shallower sandy, permeable layers. The eruption, regardless the triggering cause—natural or man-made, reveals the potential hazard of gas-charged sediments in the delta, even at distances far from the volcanic edifices.

Exploring Our Solar System with CubeSats and NanoSats

NASA Technical Reports Server (NTRS)

Freeman, Anthony; Norton, Charles

2015-01-01

The Jet Propulsion Laboratory (JPL) is NASA's lead center for robotic exploration of our solar system. We are known for our large, flagship missions, such as Voyager, which gave humanity its first close look at Jupiter and Saturn; and the Mars Rovers, which have excited millions worldwide with their daring landing exploits. Less familiar to those outside NASA may be our role in developing the Kepler mission, which has discovered more than 2000 planets around other stars; or the recently launched Soil Moisture Active Passive (SMAP) mission, one of many JPL Earth Science missions. A recent JPL initiative has emphasized low cost missions that use rapidly evolving technology developed for CubeSats and NanoSat s to explore our solar system. Costs are significantly lower (by one or two orders of magnitude) than for conventional JPL missions, and development time is also significantly shorter. At present 21 such CubeSat flight projects are under way at the laboratory with various partners : some in flight, some in development, some in advanced formulation. Four are planned as deep space missions. To succeed in exploring deep space CubeSat/NanoSat missions have to address several challenges: the more severe radiation environment, communications and navigation at a distance, propulsion, and packaging of instruments that can return valuable science into a compact volume/mass envelope. Instrument technologies, including cameras, magnetometers, spectrometers, radiometers, and even radars are undergoing miniaturization to fit on these smaller platforms. Other key technologies are being matured for smallsats and NanoSats in deep space, including micro -electric propulsion, compact radio (and optical) communications, and onboard data reduction. This paper will describe missions that utilize these developments including the first two deep space CubeSats (INSPIRE), planned for launch in 2017; the first pair of CubeSats to be sent to another planet (MARCO), manifested with the InSight Mars lander launch in March of 2016; a helicopter "drone" on Mars to extend the reach of future rovers; plans for a Lunar Flashlight mission to shine a light on the permanently shadowed craters of the Moon's poles; a Near Earth Asteroid CubeSat missio n; and a CubeSat constellation to demonstrate time series measurements of storm systems on Earth. From these beginnings, the potential for CubeSats and NanoSats to add to our knowledge of the solar system could easily grow exponentially. Imagine if every deep space mission carried one or more CubeSats that could operate independently (even for a brief period) on arrival at their target body. At only incremental additional cost, such spacecraft could go closer, probe deeper, and provide science measurements that we would not risk with the host spacecraft. This paper will describe examples including a NanoSat to probe the composition of Venus' atmosphere, impactors and close flybys of Europa, lunar probes, and soft landers for the moons of Mars. Low cost access to deep space also offers the potential for independent CubeSat/NanoSat missions - allowing us to characterize the population of near Earth asteroids for example, deploy a constellation around Venus, or take closer looks at the asteroid belt.

Comparing Vesta's Surface Roughness to the Moon Using Bistatic Radar Observations by the Dawn Mission

NASA Astrophysics Data System (ADS)

Palmer, E. M.; Heggy, E.; Kofman, W. W.; Moghaddam, M.

2015-12-01

The first orbital bistatic radar (BSR) observations of a small body have been conducted opportunistically by NASA's Dawn spacecraft at Asteroid Vesta using the telecommunications antenna aboard Dawn to transmit and the Deep Space Network 70-meter antennas on Earth to receive. Dawn's high-gain communications antenna continuously transmitted right-hand circularly polarized radio waves (4-cm wavelength), and due to the opportunistic nature of the experiment, remained in a fixed orientation pointed toward Earth throughout each BSR observation. As a consequence, Dawn's transmitted radio waves scattered from Vesta's surface just before and after each occultation of the Dawn spacecraft behind Vesta, resulting in surface echoes at highly oblique incidence angles of greater than 85 degrees, and a small Doppler shift of ~2 Hz between the carrier signal and surface echoes from Vesta. We analyze the power and Doppler spreading of Vesta's surface echoes to assess surface roughness, and find that Vesta's area-normalized radar cross section ranges from -8 to -17 dB, which is notably much stronger than backscatter radar cross section values reported for the Moon's limbs (-20 to -35 dB). However, our measurements correspond to the forward scattering regime--such that at high incidence, radar waves are expected to scatter more weakly from a rough surface in the backscatter direction than that which is scattered forward. Using scattering models of rough surfaces observed at high incidence, we report on the relative roughness of Vesta's surface as compared to the Moon and icy Galilean satellites. Through this, we assess the dominant processes that have influenced Vesta's surface roughness at centimeter and decimeter scales, which are in turn applicable to assisting future landing, sampling and orbital missions of other small bodies.

The J-2X Upper Stage Engine: From Design to Hardware

NASA Technical Reports Server (NTRS)

Byrd, Thomas

2010-01-01

NASA is well on its way toward developing a new generation of launch vehicles to support of national space policy to retire the Space Shuttle fleet, complete the International Space Station, and return to the Moon as the first step in resuming this nation s exploration of deep space. The Constellation Program is developing the launch vehicles, spacecraft, surface systems, and ground systems to support those plans. Two launch vehicles will support those ambitious plans the Ares I and Ares V. (Figure 1) The J-2X Upper Stage Engine is a critical element of both of these new launchers. This paper will provide an overview of the J-2X design background, progress to date in design, testing, and manufacturing. The Ares I crew launch vehicle will lift the Orion crew exploration vehicle and up to four astronauts into low Earth orbit (LEO) to rendezvous with the space station or the first leg of mission to the Moon. The Ares V cargo launch vehicle is designed to lift a lunar lander into Earth orbit where it will be docked with the Orion spacecraft, and provide the thrust for the trans-lunar journey. While these vehicles bear some visual resemblance to the 1960s-era Saturn vehicles that carried astronauts to the Moon, the Ares vehicles are designed to carry more crew and more cargo to more places to carry out more ambitious tasks than the vehicles they succeed. The government/industry team designing the Ares rockets is mining a rich history of technology and expertise from the Shuttle, Saturn and other programs and seeking commonality where feasible between the Ares crew and cargo rockets as a way to minimize risk, shorten development times, and live within the budget constraints of its original guidance.

Processing of emotional information in the human subthalamic nucleus.

PubMed

Buot, Anne; Welter, Marie-Laure; Karachi, Carine; Pochon, Jean-Baptiste; Bardinet, Eric; Yelnik, Jérôme; Mallet, Luc

2013-12-01

The subthalamic nucleus (STN) is an efficient target for treating patients with Parkinson's disease as well as patients with obsessive-compulsive disorder (OCD) using high frequency stimulation (HFS). In both Parkinson's disease and OCD patients, STN-HFS can trigger abnormal behaviours, such as hypomania and impulsivity. To investigate if this structure processes emotional information, and whether it depends on motor demands, we recorded subthalamic local field potentials in 16 patients with Parkinson's disease using deep brain stimulation electrodes. Recordings were made with and without dopaminergic treatment while patients performed an emotional categorisation paradigm in which the response varied according to stimulus valence (pleasant, unpleasant and neutral) and to the instruction given (motor, non-motor and passive). Pleasant, unpleasant and neutral stimuli evoked an event related potential (ERP). Without dopamine medication, ERP amplitudes were significantly larger for unpleasant compared with neutral pictures, whatever the response triggered by the stimuli; and the magnitude of this effect was maximal in the ventral part of the STN. No significant difference in ERP amplitude was observed for pleasant pictures. With dopamine medication, ERP amplitudes were significantly increased for pleasant compared with neutral pictures whatever the response triggered by the stimuli, while ERP amplitudes to unpleasant pictures were not modified. These results demonstrate that the ventral part of the STN processes the emotional valence of stimuli independently of the motor context and that dopamine enhances processing of pleasant information. These findings confirm the specific involvement of the STN in emotional processes in human, which may underlie the behavioural changes observed in patients with deep brain stimulation.

Perceptual distance and the moon illusion.

PubMed

Kaufman, Lloyd; Vassiliades, Vassias; Noble, Richard; Alexander, Robert; Kaufman, James; Edlund, Stefan

2007-01-01

The elevated moon usually appears smaller than the horizon moon of equal angular size. This is the moon illusion. Distance cues may enable the perceptual system to place the horizon moon at an effectively greater distance than the elevated moon, thus making it appear as larger. This explanation is related to the size-distance invariance hypothesis. However, the larger horizon moon is usually judged as closer than the smaller zenith moon. A bias to expect an apparently large object to be closer than a smaller object may account for this conflict. We designed experiments to determine if unbiased sensitivity to illusory differences in the size and distance of the moon (as measured by d') is consistent with SDIH. A moon above a 'terrain' was compared in both distance and size to an infinitely distant moon in empty space (the reduction moon). At a short distance the terrain moon was adjudged as both closer and smaller than the reduction moon. But these differences could not be detected at somewhat greater distances. At still greater distances the terrain moon was perceived as both more distant and larger than the reduction moon. The distances at which these transitions occurred were essentially the same for both distance and size discrimination tasks, thus supporting SDIH.

Properties of an Earth-like planet orbiting a Sun-like star: Earth observed by the EPOXI mission.

PubMed

Livengood, Timothy A; Deming, L Drake; A'hearn, Michael F; Charbonneau, David; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Meadows, Victoria S; Robinson, Tyler D; Seager, Sara; Wellnitz, Dennis D

2011-11-01

NASA's EPOXI mission observed the disc-integrated Earth and Moon to test techniques for reconnoitering extrasolar terrestrial planets, using the Deep Impact flyby spacecraft to observe Earth at the beginning and end of Northern Hemisphere spring, 2008, from a range of ∼1/6 to 1/3 AU. These observations furnish high-precision and high-cadence empirical photometry and spectroscopy of Earth, suitable as "ground truth" for numerically simulating realistic observational scenarios for an Earth-like exoplanet with finite signal-to-noise ratio. Earth was observed at near-equatorial sub-spacecraft latitude on 18-19 March, 28-29 May, and 4-5 June (UT), in the range of 372-4540 nm wavelength with low visible resolving power (λ/Δλ=5-13) and moderate IR resolving power (λ/Δλ=215-730). Spectrophotometry in seven filters yields light curves at ∼372-948 nm filter-averaged wavelength, modulated by Earth's rotation with peak-to-peak amplitude of ≤20%. The spatially resolved Sun glint is a minor contributor to disc-integrated reflectance. Spectroscopy at 1100-4540 nm reveals gaseous water and carbon dioxide, with minor features of molecular oxygen, methane, and nitrous oxide. One-day changes in global cloud cover resulted in differences between the light curve beginning and end of ≤5%. The light curve of a lunar transit of Earth on 29 May is color-dependent due to the Moon's red spectrum partially occulting Earth's relatively blue spectrum. The "vegetation red edge" spectral contrast observed between two long-wavelength visible/near-IR bands is ambiguous, not clearly distinguishing between the verdant Earth diluted by cloud cover versus the desolate mineral regolith of the Moon. Spectrophotometry in at least one other comparison band at short wavelength is required to distinguish between Earth-like and Moon-like surfaces in reconnaissance observations. However, measurements at 850 nm alone, the high-reflectance side of the red edge, could be sufficient to establish periodicity in the light curve and deduce Earth's diurnal period and the existence of fixed surface units.

Magma ascent and magmatism controlled by cratering on the Moon

NASA Astrophysics Data System (ADS)

Michaut, C.; Pinel, V.

2016-12-01

The lunar primary crust was formed by flotation of light plagioclase minerals on top of the lunar magma ocean, resulting in a relatively light and thick crust. This crust acted as a barrier for the denser primary mantle melts: mare basalts erupted primarily within large impact basins where at least part of this crust was removed. Thus, lunar magmas likely stored at the base of or deep in the lunar crust and the ascent of magma to shallow depths probably required local or regional tensional stresses. On the Moon, evidences of shallow sites of magmatism are mostly concentrated within old and degraded simple and complex craters that surround the Mare basalts. Impacts, that were numerous in the early times of the Moon, created depressions at the lunar surface that induced specific states of stress. Below a crater, magma ascent is helped by the tensional stresses caused by the depression up to a depth that is close to the crater radius. However, many craters that are the sites of shallow magmatism are less than 10 to 20 km in radius and are equally situated in regions of thin (i.e. 20 km) or thick (i.e. 60km) crust suggesting that the depression, although significant enough to control magma emplacement, was not large enough to induce it. Since the sites of magmatism surround the mare basalts, we explore the common idea that the weight of the Mare induced a tensile state of stress in the surrounding regions. We constrain the regional state of stress that was necessary to help magma ascent to shallow depths but was low enough for the local depression due to a crater to control magma emplacement. This state of stress is consistent with a relatively thin but extended mare load. We also show that the depression due to the crater probably caused the horizontalization and hence the storage of the magmatic intrusion at shallow depth below the crater. In the end, because of the neutral buoyancy of magmas in the crust and the lack of tectonic processes, impact processes largely controlled magma transport and secondary crust formation on the Moon.

Calibration Image of Earth by Mars Color Imager

NASA Technical Reports Server (NTRS)

2005-01-01

Three days after the Mars Reconnaissance Orbiter's Aug. 12, 2005, launch, the NASA spacecraft was pointed toward Earth and the Mars Color Imager camera was powered up to acquire a suite of color and ultraviolet images of Earth and the Moon. When it gets to Mars, the Mars Color Imager's main objective will be to obtain daily global color and ultraviolet images of the planet to observe martian meteorology by documenting the occurrence of dust storms, clouds, and ozone. This camera will also observe how the martian surface changes over time, including changes in frost patterns and surface brightness caused by dust storms and dust devils.

The purpose of acquiring an image of Earth and the Moon just three days after launch was to help the Mars Color Imager science team obtain a measure, in space, of the instrument's sensitivity, as well as to check that no contamination occurred on the camera during launch. Prior to launch, the team determined that, three days out from Earth, the planet would only be about 4.77 pixels across, and the Moon would be less than one pixel in size, as seen from the Mars Color Imager's wide-angle perspective. If the team waited any longer than three days to test the camera's performance in space, Earth would be too small to obtain meaningful results.

The images were acquired by turning Mars Reconnaissance Orbiter toward Earth, then slewing the spacecraft so that the Earth and Moon would pass before each of the five color and two ultraviolet filters of the Mars Color Imager. The distance to Earth was about 1,170,000 kilometers (about 727,000 miles).

This image shows a color composite view of Mars Color Imager's image of Earth. As expected, it covers only five pixels. This color view has been enlarged five times. The Sun was illuminating our planet from the left, thus only one quarter of Earth is seen from this perspective. North America was in daylight and facing toward the camera at the time the picture was taken; the data from the camera were being transmitted in real time to the Deep Space Network antennas in Goldstone, California.

Cancer Risk from Exposure to Galactic Cosmic Rays - Implications for Human Space Exploration

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Durant, marco

2006-01-01

Current space programs are shifting toward planetary exploration, and in particular towards human missions to the moon and Mars. However, space radiation is a major barrier to human exploration of the solar system because the biological effects of high-energy and charge (HZE) ions, which are the main contributors to radiation risks in deep space, are poorly understood. Predictions of the nature and magnitude of the risks posed by space radiation are subject to very large uncertainties. Great efforts have been dedicated worldwide in recent years toward a better understanding of the oncogenic potential of galactic cosmic rays. A review of the new results in this field will be presented here.

Biological Technologies for Life Beyond Low Earth Orbit (BT4LBLEO): Study Introductions and Synopsis

NASA Technical Reports Server (NTRS)

Hines, John W.

2011-01-01

The study will address the following mission concerns: -Extended human presence in the environments of deep space as well as the Moon and Mars will require a solid biological understanding of the integrated effects of diminished gravity, enhanced radiation, and transit- and destination-specific variables from the sub-cellular to the whole organism level. -Biological and associated technologies for biological and robotic precursor missions to realize future objectives for space colonization. -Surfaces, gravity levels, radiation environments, and atmospheres of these nearest neighbors are radically different in chemical and geological make-up from those on our home planet, and all of these contributory effects must be considered.

Trade studies for nuclear space power systems

NASA Technical Reports Server (NTRS)

Smith, John M.; Bents, David J.; Bloomfield, Harvey S.

1991-01-01

As human visions of space applications expand and as we probe further out into the universe, our needs for power will also expand, and missions will evolve which are enabled by nuclear power. A broad spectrum of missions which are enhanced or enabled by nuclear power sources have been defined. These include Earth orbital platforms, deep space platforms, planetary exploration, and terrestrial resource exploration. The recently proposed Space Exploration Initiative (SEI) to the Moon and Mars has more clearly defined these missions and their power requirements. Presented here are results of recent studies of radioisotope and nuclear reactor energy sources, combined with various energy conversion devices for Earth orbital applications, SEI lunar/Mars rovers, surface power, and planetary exploration.

Uplink Array Calibration via Far-Field Power Maximization

NASA Technical Reports Server (NTRS)

Vilnrotter, V.; Mukai, R.; Lee, D.

2006-01-01

Uplink antenna arrays have the potential to greatly increase the Deep Space Network s high-data-rate uplink capabilities as well as useful range, and to provide additional uplink signal power during critical spacecraft emergencies. While techniques for calibrating an array of receive antennas have been addressed previously, proven concepts for uplink array calibration have yet to be demonstrated. This article describes a method of utilizing the Moon as a natural far-field reflector for calibrating a phased array of uplink antennas. Using this calibration technique, the radio frequency carriers transmitted by each antenna of the array are optimally phased to ensure that the uplink power received by the spacecraft is maximized.

The Lunar Laser Communication Demonstration: NASA's First Step Toward Very High Data Rate Support of Science and Exploration Missions

NASA Astrophysics Data System (ADS)

Boroson, Don M.; Robinson, Bryan S.

2014-12-01

Future NASA missions for both Science and Exploration will have needs for much higher data rates than are presently available, even with NASA's highly-capable Space- and Deep-Space Networks. As a first step towards this end, for one month in late 2013, NASA's Lunar Laser Communication Demonstration (LLCD) successfully demonstrated for the first time high-rate duplex laser communications between a satellite in lunar orbit, the Lunar Atmosphere and Dust Environment Explorer (LADEE), and multiple ground stations on the Earth. It constituted the longest-range laser communication link ever built and demonstrated the highest communication data rates ever achieved to or from the Moon.

Observation of Possible Lava Tube Skylights by SELENE cameras

NASA Astrophysics Data System (ADS)

Haruyama, Junichi; Hiesinger, Harald; van der Bogert, Carolyn

We have discovered three deep hole-structures on the Moon in the Terrain Camera and Multi-band Imager on the SELENE. These holes are large depth to diameter ratios: Marius Hills Hole (MHH) is 65 m in diameter and 88-90 m in depth, Mare Tranquillitatis Hole (MTH) is 120 x 110 m in diameter and 180 m in depth, and Mare Ingenii Hole (MIH) is 140 x 110 m in diameter and deeper than 90 m. No volcanic material from the holes nor dike-relating pit craters is seen around the holes. They are possible lava tube skylights. These holes and possibly connected tubes have a lot of scientific interests and high potentialities as lunar bases.

Wolf: What's On the Lunar Farside?

NASA Technical Reports Server (NTRS)

2008-01-01

WOLF (What's On the Lunar Farside?) is a lunar sample return mission to the South Pole-Aitken (SPA) Basin, located on the farside of the moon, seeking to answer some of the remaining questions about our solar system. Through the return and analysis of SPA samples, scientists can constrain the period of inner solar system late heavy bombardment and gain momentous knowledge of the SPA basin. WOLF provides the opportunity for mankind's progression in further understanding our solar system, its history, and unknowns surrounding the lunar farside. The orbiter will provide intermittent, direct communication between the lander and ground operations via the Deep Space Network (DSN). Received images and spectrometry will aid in real-time sample selection.

Intra-Extra Vehicular Activity Apollo Spacesuits

NASA Technical Reports Server (NTRS)

Thomas, Kenneth S.

2016-01-01

Kenneth Thomas will discuss the Apollo Intra-Extra Vehicular Activity (IEVA) spacesuits, which supported launch and reentry and extra-vehicular activity. This program was NASA's first attempt to develop a new suit design from requirements and concepts. Mr. Thomas will chronicle the challenges, developments, struggles, and solutions that culminated in the system that allowed the first human exploration of the Moon and deep space (outside low-Earth orbit). Apollo pressure suit designs allowed the heroic repair of the Skylab space station and supported the first U.S. and Russian spacecraft docking during the Apollo Soyuz Test Project. Mr. Thomas will also discuss the IEVA suits' successes and challenges associated with the IEVA developments of the 1960s.

Environmental control and life support technologies for advanced manned space missions

NASA Technical Reports Server (NTRS)

Powell, F. T.; Wynveen, R. A.; Lin, C.

1986-01-01

Regenerative environmental control and life support system (ECLSS) technologies are found by the present evaluation to have reached a degree of maturity that recommends their application to long duration manned missions. The missions for which regenerative ECLSSs are attractive in virtue of the need to avoid expendables and resupply requirements have been identified as that of the long duration LEO Space Station, long duration stays at GEO, a permanently manned lunar base (or colony), manned platforms located at the earth-moon libration points L4 or L5, a Mars mission, deep space exploration, and asteroid exploration. A comparison is made between nonregenerative and regenerative ECLSSs in the cases of 10 essential functions.

Lunar Roving Vehicle parked in lunar depression on slope of Stone Mountain

NASA Image and Video Library

1972-04-22

AS16-107-17473 (22 April 1972) --- The Lunar Roving Vehicle (LRV) appears to be parked in a deep lunar depression, on the slope of Stone Mountain. This photograph of the lunar scene at Station No. 4 was taken during the second Apollo 16 extravehicular activity (EVA) at the Descartes landing site. A sample collection bag is in the right foreground. Note field of small boulders at upper right. While astronauts John W. Young, commander, and Charles M. Duke Jr., lunar module pilot, descended in the Lunar Module (LM) "Orion" to explore the moon, astronaut Thomas K. Mattingly II, command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit.

Effects of nuclear cross sections at different energies on the radiation hazard from galactic cosmic rays.

PubMed

Lin, Z W; Adams, J H

2007-03-01

The radiation hazard for astronauts from galactic cosmic rays (GCR) is a major obstacle to long-duration human space exploration. Space radiation transport codes have been developed to calculate the radiation environment on missions to the Moon, Mars, and beyond. We have studied how uncertainties in fragmentation cross sections at different energies affect the accuracy of predictions from such radiation transport calculations. We find that, in deep space, cross sections at energies between 0.3 and 0.85 GeV/nucleon have the largest effect in solar maximum GCR environments. At the International Space Station, cross sections at higher energies have the largest effect due to the geomagnetic cutoff.

Science in Exploration: From the Moon to Mars and Back Home to Earth

NASA Technical Reports Server (NTRS)

Garvin, James B.

2007-01-01

NASA is embarking on a grand journey of exploration that naturally integrates the past successes of the Apollo missions to the Moon, as well as robotic science missions to Mars, to Planet Earth, and to the broader Universe. The US Vision for Space Exporation (VSE) boldly lays out a plan for human and robotic reconnaissance of the accessible Universe, starting with the surface of the Moon, and later embracing the surface of Mars. Sustained human and robotic access to the Moon and Mars will enable a new era of scientific investigation of our planetary neighbors, tied to driving scientific questions that pertain to the evolution and destiny of our home planet, but which also can be related to the search habitable worlds across the nearby Universe. The Apollo missions provide a vital legacy for what can be learned from the Moon, and NASA is now poised to recapture the lunar frontier starting with the flight of the Lunar Reconnaissance Orbiter (LRO) in late 2008. LRO will provide a new scientific context from which joint human and robotic exploration will ensue, guided by objectives some of which are focused on the grandest scientific challenges imaginable : Where did we come from? Are we alone? and Where are we going? The Moon will serve as an essential stepping stone for sustained human access and exploration of deep space and as a training ground while robotic missions with ever increasing complexity probe the wonders of Mars. As we speak, an armada of spacecraft are actively investigating the red planet both from orbit (NASA's Mars Reconnaissance Orbiter and Mars Odyssey Orbiter, plus ESA's Mars Express) and from the surface (NASA's twin Mars Exploration Rovers, and in 2008 NASA's Phoenix polar lander). The dramatically changing views of Mars as a potentially habitable world, with its own flavor of global climate change and unique climate records, provides a new vantage point from which to observe and question the workings of our own planet Earth. By 2010 NASA will have its first mobile analytical laboratory operating on the surface of Mars (Mars Science Laboratory) in search of potentially subtle expressions of past life or at least of life-hospitable environments. Meanwhile back here on Planet Earth, NASA will be continuing to implement an increasingly comprehensive program of robotic missions that address major issues associated with global climate variability, and the "state variables" that affect the quality of human life on our home planet. Ultimately, the fmits of NASA's emergent program of Exploration (VSE) will provide never-beforepossible opportunities for scientific leadership and advancement, culminating in a new state of awareness from which to better plan for the sustainability of life on Earth and for extending Earth life to the Moon and eventually to Mars. As NASA nears its 50th anniversary, the unimaginable and unexpected wealth of strategic knowledge its missions have generated about Earth, the Universe, and our local Solar System boggles the mind and serves as a legacy of knowledge for Educators to inspire future generations.

The dust masses of powerful radio galaxies: clues to the triggering of their activity

NASA Astrophysics Data System (ADS)

Tadhunter, C.; Dicken, D.; Morganti, R.; Konyves, V.; Ysard, N.; Nesvadba, N.; Ramos Almeida, C.

2014-11-01

We use deep Herschel Space Observatory observations of a 90 per cent complete sample of 32 intermediate-redshift 2Jy radio galaxies (0.05 < z < 0.7) with strong emission lines to estimate the dust masses of their host galaxies and thereby investigate the triggering mechanisms for their quasar-like AGN. The dust masses derived for the radio galaxies (7.2 × 105 < Md < 2.6 × 108 M⊙) are intermediate between those of quiescent elliptical galaxies on the one hand, and ultraluminous infrared galaxies (ULIRGs) on the other. Consistent with simple models for the co-evolution of supermassive black holes and their host galaxies, these results suggest that most radio galaxies represent the late time re-triggering of AGN activity via mergers between the host giant elliptical galaxies and companion galaxies with relatively low gas masses. However, a minority of the radio galaxies in our sample (˜20 per cent) have high, ULIRG-like dust masses, along with evidence for prodigious star formation activity. The latter objects are more likely to have been triggered in major, gas-rich mergers that represent a rapid growth phase for both their host galaxies and their supermassive black holes.

Oxygen, ecology, and the Cambrian radiation of animals

PubMed Central

Sperling, Erik A.; Frieder, Christina A.; Raman, Akkur V.; Girguis, Peter R.; Levin, Lisa A.; Knoll, Andrew H.

2013-01-01

The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator–prey “arms races” can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation. PMID:23898193

Neurophysiological and clinical effects of dry needling in patients with upper trapezius myofascial trigger points.

PubMed

Abbaszadeh-Amirdehi, Maryam; Ansari, Noureddin Nakhostin; Naghdi, Soofia; Olyaei, Gholamreza; Nourbakhsh, Mohammad Reza

2017-01-01

Dry needling (DN) is a widely used in treatment of myofascial trigger points (MTrPs). The purpose of this pretest-posttest clinical trial was to investigate the neurophysiological and clinical effects of DN in patients with MTrPs. A sample of 20 patients (3 man, 17 women; mean age 31.7 ± 10.8) with upper trapezius MTrPs received one session of deep DN. The outcomes of neuromuscular junction response (NMJR), sympathetic skin response (SSR), pain intensity (PI) and pressure pain threshold (PPT) were measured at baseline and immediately after DN. There were significant improvements in SSR latency and amplitude, pain, and PPT after DN. The NMJR decreased and returned to normal after DN. A single session of DN to the active upper trapezius MTrP was effective in improving pain, PPT, NMJR, and SSR in patients with myofascial trigger points. Further studies are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unprecedented pressure increase in deep magma reservoir triggered by lava-dome collapse

NASA Astrophysics Data System (ADS)

Voight, B.; Linde, A. T.; Sacks, I. S.; Mattioli, G. S.; Sparks, R. S. J.; Elsworth, D.; Hidayat, D.; Malin, P. E.; Shalev, E.; Widiwijayanti, C.; Young, S. R.; Bass, V.; Clarke, A.; Dunkley, P.; Johnston, W.; McWhorter, N.; Neuberg, J.; Williams, P.

2006-02-01

The collapse of the Soufrière Hills Volcano lava dome on Montserrat in July 2003 is the largest such event worldwide in the historical record. Here we report on borehole dilatometer data recording a remarkable and unprecedented rapid (~600s) pressurisation of a magma chamber, triggered by this surface collapse. The chamber expansion is indicated by an expansive offset at the near dilatometer sites coupled with contraction at the far site. By analyzing the strain data and using added constraints from experimental petrology and long-term edifice deformation from GPS geodesy, we prefer a source centered at approximately 6 km depth below the crater for an oblate spheroid with overpressure increase of order 1 MPa and average radius ~1 km. Pressurisation is attributed to growth of 1-3% of gas bubbles in supersaturated magma, triggered by the dynamics of surface unloading. Recent simulations demonstrate that pressure recovery from bubble growth can exceed initial pressure drop by nearly an order of magnitude.

Petrology of the 2004-2006 Mount St. Helens lava dome -- implications for magmatic plumbing and eruption triggering: Chapter 30 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

USGS Publications Warehouse

Pallister, John S.; Thornber, Carl R.; Cashman, Katharine V.; Clynne, Michael A.; Lowers, Heather; Mandeville, Charles W.; Brownfield, Isabelle K.; Meeker, Gregory P.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

The question of new versus residual magma has implications for the long-term eruptive behavior of Mount St. Helens, because arrival of a new batch of dacitic magma from the deep crust could herald the beginning of a new long-term cycle of eruptive activity. It is also important to our understanding of what triggered the eruption and its future course. Two hypotheses for triggering are considered: (1) top-down fracturing related to the shallow groundwater system and (2) an increase in reservoir pressure brought about by recent magmatic replenishment. With respect to the future course of the eruption, similarities between textures and character of eruption of the 2004-6 dome and the long-duration (greater than 100 years) pre-1980 summit dome, along with the low eruptive rate of the current eruption, suggest that the eruption could continue sluggishly or intermittently for years to come.

Detecting modification of biomedical events using a deep parsing approach.

PubMed

Mackinlay, Andrew; Martinez, David; Baldwin, Timothy

2012-04-30

This work describes a system for identifying event mentions in bio-molecular research abstracts that are either speculative (e.g. analysis of IkappaBalpha phosphorylation, where it is not specified whether phosphorylation did or did not occur) or negated (e.g. inhibition of IkappaBalpha phosphorylation, where phosphorylation did not occur). The data comes from a standard dataset created for the BioNLP 2009 Shared Task. The system uses a machine-learning approach, where the features used for classification are a combination of shallow features derived from the words of the sentences and more complex features based on the semantic outputs produced by a deep parser. To detect event modification, we use a Maximum Entropy learner with features extracted from the data relative to the trigger words of the events. The shallow features are bag-of-words features based on a small sliding context window of 3-4 tokens on either side of the trigger word. The deep parser features are derived from parses produced by the English Resource Grammar and the RASP parser. The outputs of these parsers are converted into the Minimal Recursion Semantics formalism, and from this, we extract features motivated by linguistics and the data itself. All of these features are combined to create training or test data for the machine learning algorithm. Over the test data, our methods produce approximately a 4% absolute increase in F-score for detection of event modification compared to a baseline based only on the shallow bag-of-words features. Our results indicate that grammar-based techniques can enhance the accuracy of methods for detecting event modification.

An efficient workflow to accurately compute groundwater recharge for the study of rainfall-triggered deep-seated landslides, application to the Séchilienne unstable slope (western Alps)

NASA Astrophysics Data System (ADS)

Vallet, A.; Bertrand, C.; Fabbri, O.; Mudry, J.

2015-01-01

Pore water pressure build-up by recharge of underground hydrosystems is one of the main triggering factors of deep-seated landslides. In most deep-seated landslides, pore water pressure data are not available since piezometers, if any, have a very short lifespan because of slope movements. As a consequence, indirect parameters, such as the calculated recharge, are the only data which enable understanding landslide hydrodynamic behaviour. However, in landslide studies, methods and recharge-area parameters used to determine the groundwater recharge are rarely detailed. In this study, the groundwater recharge is estimated with a soil-water balance based on characterisation of evapotranspiration and parameters characterising the recharge area (soil available water capacity, runoff and vegetation coefficient). A workflow to compute daily groundwater recharge is developed. This workflow requires the records of precipitation, air temperature, relative humidity, solar radiation and wind speed within or close to the landslide area. The determination of the parameters of the recharge area is based on a spatial analysis requiring field observations and spatial data sets (digital elevation models, aerial photographs and geological maps). This study demonstrates that the performance of the correlation with landslide displacement velocity data is significantly improved using the recharge estimated with the proposed workflow. The coefficient of determination obtained with the recharge estimated with the proposed workflow is 78% higher on average than that obtained with precipitation, and is 38% higher on average than that obtained with recharge computed with a commonly used simplification in landslide studies (recharge = precipitation minus non-calibrated evapotranspiration method).

NASA Armstrong Flight Research Center's communications facility with radar dish and the eclipsed moon overhead during Jan. 31 Super Blue Blood Moon.

NASA Image and Video Library

2018-01-31

California's NASA Armstrong Flight Research Center photographer Carla Thomas takes photos on January 31 of the rare opportunity to capture a supermoon, a blue moon and a lunar eclipse at the same time. A supermoon occurs when the Moon is closer to Earth in its orbit and appearing 14 percent brighter than usual. As the second full moon of the month, this moon is also commonly known as a blue moon, though it will not be blue in appearance. The super blue moon passed through Earth's shadow and took on a reddish tint, known as a blood moon. This total lunar eclipse occurs when the Sun, Earth, and a full moon form a near-perfect lineup in space. The Moon passes directly behind the Earth into its umbra (shadow).

SMART-1: key technologies and autonomy implementations

NASA Astrophysics Data System (ADS)

Elfving, A.; Stagnaro, L.; Winton, A.

2003-01-01

SMART-1 is the first of the Small Missions for Advanced Research in Technology of the ESA Horizons 2000 Science Plan. The main mission objective of SMART-1 is to demonstrate innovative and key technologies for scientific deep-space missions. One of the key technologies is the solar electric propulsion used as primary propulsion. The electric propulsion will be using 1400 W to transfer the 350 kg spacecraft from an Ariane 5 standard GTO to an elliptic Moon polar orbit, 10000×300 km. The total mission time is 24 months including a maximum of 18 months transfer time. The spacecraft development entered the detailed design and implementation phase in October 1999, under the responsibility of the Swedish Space Cooperation as prime contractor, and the flight acceptance is targeted for the 3rd quarter of 2002. The committed total life cost budget is 84 million Euro. Apart from the in-orbit demonstration of electric propulsion as primary propulsion, SMART-1 is implementing many other enabling technologies for deep-space missions such as deep-space transponder with communication in X-band for uplink and in X- and Ka-band for downlink, highly integrated and radiation tolerant microprocessors, FPGAs and memories, high on-board autonomy driven by ground communication only once per 4 days, maximum available power to electric propulsion by centralised and software-controlled power management, minimum propellant consumption through innovative angular momentum management. In addition, the spacecraft avionics design is tailored to the low-cost philosophy by enabling flexible integration of commercial off the shelf (COTS) equipment. The scientific instruments, five in total, support characterisation of the electric propulsion thrust environment during the long transfer phase and detailed imaging and spectroscopy of the lunar surface in visible, infrared and X-ray during the Moon orbiting phase. Several of the instruments implement new enabling technologies, e.g. swept charge devices for the X-ray spectrometer and quarts gratings for the near-infrared reflectance spectrometer. The paper summarises the baseline mission design, the projected scientific and technology output, and describe the spacecraft bus design. The main part of the paper highlights and elaborate on a number of spacecraft bus technologies; the on-board autonomy, the avionics design, and the X/Ka-band transponder.

Out of Disaster Comes Opportunity: Initial Lessons from Teacher Mentoring in Banda Aceh, Indonesia

ERIC Educational Resources Information Center

Lesnick, Joy; Schultz, Katherine

2006-01-01

On December 26, 2004, a 9.0 magnitude earthquake--the most powerful in more than 40 years--struck deep under the Indian Ocean. It was centered about 100 miles southwest off the coast of Aceh, Indonesia, and triggered massive tsunamis across the coasts of Asia and Africa. In Aceh province, located at the northwest tip of the island of Sumatra in…

Human Bone Matrix Changes During Deep Saturation Dives

DTIC Science & Technology

2008-08-08

of theories have been investigated to elucidate this 2 separate factor. They include fat embolism , decompression triggered intravascular...arterial gas embolism . In bone, bubbles can also cause a mechanical blockage of blood flow that result in tissue damage and necrosis. Blood flow is...exposures, but the longest follow-up to date is only 10 years.11 If lesions progress and cause femoral fractures or osteoarthritis, the typical

"Students Make History Every Day Just by Sitting on These Steps": Performative Spaces and Re-Genring in the South

ERIC Educational Resources Information Center

Hunma, Aditi

2018-01-01

Students' call for decolonising the curriculum has triggered deep reflection about what we teach and how we teach it, but equally, about the role of pedagogic spaces in recognising students as agents in their learning. This paper is situated within the field of academic literacies, where students' engagement with texts is seen as being…

Non-linear processes in the Earth atmosphere boundary layer

NASA Astrophysics Data System (ADS)

Grunskaya, Lubov; Valery, Isakevich; Dmitry, Rubay

2013-04-01

The work is connected with studying electromagnetic fields in the resonator Earth-Ionosphere. There is studied the interconnection of tide processes of geophysical and astrophysical origin with the Earth electromagnetic fields. On account of non-linear property of the resonator Earth-Ionosphere the tides (moon and astrophysical tides) in the electromagnetic Earth fields are kinds of polyharmonic nature. It is impossible to detect such non-linear processes with the help of the classical spectral analysis. Therefore to extract tide processes in the electromagnetic fields, the method of covariance matrix eigen vectors is used. Experimental investigations of electromagnetic fields in the atmosphere boundary layer are done at the distance spaced stations, situated on Vladimir State University test ground, at Main Geophysical Observatory (St. Petersburg), on Kamchatka pen., on Lake Baikal. In 2012 there was continued to operate the multichannel synchronic monitoring system of electrical and geomagnetic fields at the spaced apart stations: VSU physical experimental proving ground; the station of the Institute of Solar and Terrestrial Physics of Russian Academy of Science (RAS) at Lake Baikal; the station of the Institute of volcanology and seismology of RAS in Paratunka; the station in Obninsk on the base of the scientific and production society "Typhoon". Such investigations turned out to be possible after developing the method of scanning experimental signal of electromagnetic field into non- correlated components. There was used a method of the analysis of the eigen vectors ofthe time series covariance matrix for exposing influence of the moon tides on Ez. The method allows to distribute an experimental signal into non-correlated periodicities. The present method is effective just in the situation when energetical deposit because of possible influence of moon tides upon the electromagnetic fields is little. There have been developed and realized in program components in the form of PAS instruments of processes of geophysical and man-triggered nature; to predict the presence of the features of geophysical nature in the electromagnetic field of the atmosphere boundary surface layer; to study dynamics the analyzed signals coming from the geophysical and man-triggered sources in the electrical and magnetic fields of the atmosphere boundary surface layer; to expose changes of the investigated time series in the periods preceding the appearance of the predicted phenomena; to form clusters of the time series being the features of the predicted events. On the base of the exposed clusters of the time series there have been built the predicting rules allowing to coordinate the probability of appearing the groups of the occurred events. The work is carried out with supporting of Program FPP #14.B37.210668, FPP #5.2071.2011, RFBR #11-05-97518.

Significant Dissipation of Tidal Energy in the Deep Ocean Inferred from Satellite Altimeter Data

NASA Technical Reports Server (NTRS)

Egbert, G. D.; Ray, R. D.

2000-01-01

How and where the ocean tides dissipate their energy are longstanding questions that have consequences ranging from the history of the Moon to the mixing of the oceans. Historically, the principal sink of tidal energy has been thought to be bottom friction in shallow seas. There has long been suggestive however, that tidal dissipation also occurs in the open ocean through the scattering by ocean-bottom topography of surface tides into internal waves, but estimates of the magnitude of this possible sink have varied widely. Here we use satellite altimeter data from Topex/Poseidon to map empirically the tidal energy dissipation. We show that approximately 10(exp 12) watts-that is, 1 TW, representing 25-30% of the total dissipation-occurs in the deep ocean, generally near areas of rough topography. Of the estimated 2 TW of mixing energy required to maintain the large-scale thermohaline circulation of the ocean, one-half could therefore be provided by the tides, with the other half coming from action on the surface of the ocean.

Logistics Needs for Potential Deep Space Mission Scenarios Post Asteroid Crewed Mission

NASA Technical Reports Server (NTRS)

Lopez, Pedro, Jr.

2015-01-01

A deep-space mission has been proposed to identify and redirect an asteroid to a distant retrograde orbit around the moon, and explore it by sending a crew using the Space Launch System and the Orion spacecraft. The Asteroid Redirect Crewed Mission (ARCM), which represents the third segment of the Asteroid Redirect Mission (ARM), could be performed on EM-3 or EM-4 depending on asteroid return date. Recent NASA studies have raised questions on how we could progress from current Human Space Flight (HSF) efforts to longer term human exploration of Mars. This paper will describe the benefits of execution of the ARM as the initial stepping stone towards Mars exploration, and how the capabilities required to send humans to Mars could be built upon those developed for the asteroid mission. A series of potential interim missions aimed at developing such capabilities will be described, and the feasibility of such mission manifest will be discussed. Options for the asteroid crewed mission will also be addressed, including crew size and mission duration.

Space Exploration: Where We Have Been, Where We Are and Where We Are Going: A Human Perspective

NASA Technical Reports Server (NTRS)

Tripathi, R. K.

2005-01-01

NASA is moving forward towards the agency's new vision for space exploration in the 21st Century encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. Exposure from the hazards of severe space radiation in deep space long duration missions is the show stopper. Langley has developed state-of-the-art radiation protection and shielding technology for space missions. The payload penalty demands a very stringent requirement on the design of the spacecrafts for human deep space missions. The exploration beyond low Earth orbit (LEO) to enable routine access to more interesting regions of space will require protection from the hazards of the accumulated exposures of space radiation, Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE), and minimizing the production of secondary radiation is a great advantage. The better understanding of radiation environment (GCR & SPE) and their interaction is a key to the success of the program due to the vital role and importance of cosmic rays for space missions.

Habitat Concepts for Deep Space Exploration

NASA Technical Reports Server (NTRS)

Smitherman, David; Griffin, Brand N.

2014-01-01

Future missions under consideration requiring human habitation beyond the International Space Station (ISS) include deep space habitats in the lunar vicinity to support asteroid retrieval missions, human and robotic lunar missions, satellite servicing, and Mars vehicle servicing missions. Habitat designs are also under consideration for missions beyond the Earth-Moon system, including transfers to near-Earth asteroids and Mars orbital destinations. A variety of habitat layouts have been considered, including those derived from the existing ISS designs and those that could be fabricated from the Space Launch System (SLS) propellant tanks. This paper presents a comparison showing several options for asteroid, lunar, and Mars mission habitats using ISS derived and SLS derived modules and identifies some of the advantages and disadvantages inherent in each. Key findings indicate that the larger SLS diameter modules offer built-in compatibility with the launch vehicle, single launch capability without on-orbit assembly, improved radiation protection, lighter structures per unit volume, and sufficient volume to accommodate consumables for long duration missions without resupply. The information provided with the findings includes mass and volume comparison data that should be helpful to future exploration mission planning efforts.

Magmatism on the Moon

NASA Astrophysics Data System (ADS)

Michaut, Chloé; Thorey, Clément; Pinel, Virginie

2016-04-01

Volcanism on the Moon is dominated by large fissure eruptions of mare basalt and seems to lack large, central vent, shield volcanoes as observed on all the other terrestrial planets. Large shield volcanoes are constructed over millions to several hundreds of millions of years. On the Moon, magmas might not have been buoyant enough to allow for a prolonged activity at the same place over such lengths of time. The lunar crust was indeed formed by flotation of light plagioclase minerals on top of the lunar magma ocean, resulting in a particularly light and relatively thick crust. This low-density crust acted as a barrier for the denser primary mantle melts. This is particularly evident in the fact that subsequent mare basalts erupted primarily within large impact basins where at least part of the crust was removed by the impact process. Thus, the ascent of lunar magmas might have been limited by their reduced buoyancy, leading to storage zone formation deep in the lunar crust. Further magma ascent to shallower depths might have required local or regional tensional stresses. Here, we first review evidences of shallow magmatic intrusions within the lunar crust of the Moon that consist in surface deformations presenting morphologies consistent with models of magma spreading at depth and deforming an overlying elastic layer. We then study the preferential zones of magma storage in the lunar crust as a function of the local and regional state of stress. Evidences of shallow intrusions are often contained within complex impact craters suggesting that the local depression caused by the impact exerted a strong control on magma ascent. The depression is felt over a depth equivalent to the crater radius. Because many of these craters have a radius less than 30km, the minimum crust thickness, this suggests that the magma was already stored in deeper intrusions before ascending at shallower depth. All the evidences for intrusions are also preferentially located in the internal borders and at the periphery of the main Mare basalts. The base of the Mare units potentially formed a preferential zone of magma storage. Furthermore, the weight exerted by the Mare on the lithosphere might have lead to tensional stresses on their sides that, in turn, might have helped magma ascent. In the end, because of the neutral or negative buoyancy of the magma in the crust and of the lack of tectonic processes, magma transport on the Moon has probably been largely controlled by surface processes such as impacts and volcanism itself.

LAPIS - LAnder Package Impacting a Seismometer - A Proposal for a Semi-Hard Lander Mission to the Moon

NASA Astrophysics Data System (ADS)

Lange, C.

2009-04-01

With an increased interest on the moon within the last years, at least with several missions in orbit or under development (SELENE/Japan, Chang'e/China, Chandrayaan/India and others), there is a strong demand within the German science community to participate in this initiative, building-up a national competence regarding lunar exploration. For this purpose, a Phase-0 analysis for a small lunar semi-hard landing scenario has been performed at DLR to foster future lunar exploration missions. This study's scope was to work out a more detailed insight into the design drivers and challenges and their impact on mass and cost budgets for such a mission. LAPIS has been dedicated to the investigation of the seismic activities of the moon, additionally to some other geophysical in-situ measurements at the lunar surface. In fact, the current status of the knowledge and understanding of lunar seismic activities leads to a range of open questions which have not been answered so far by the various Apollo missions in the past and could now possibly be answered by the studied LAPIS mission. Among these are the properties of the lunar core, the origin of deep and shallow moonquakes and the occurrence of micro-meteoroids. Therefore, as proposed first for LAPIS on the LEO mission, a payload of a short period micro-seismometer, based on European and American predevelopments, has been suggested. A staged mission scenario will be described, using a 2-module spacecraft with a propulsion part and a landing part, the so called LAPIS-PROP and LAPIS-LAND. In this scenario, the LAPIS-PROP module will do the cruise, until the spacecraft reaches an altitude of 100 m above the moon, after which the landing module will separate and continue to the actual semi-hard landing, which is based on deformable structures. Further technical details, e.g. considering the subsystem technologies, have been addressed within the performed study. These especially critical and uniquely challenging issues, such as the structural damping of the landing impact, the communication subsystem and the thermal subsystem have been investigated to some extent and will be described further. The described study will analyze in a unique way the technology, which is necessary to realize such a rather unconventional mission scenario, which will furthermore to a great extent contribute to the current knowledge on seismic activities on the moon.

Image is NASA Armstrong Flight Research Center’s mission support building with a composite of 16 images of the eclipsed moons overhead during Jan. 31 Super Blue Blood Moon.

NASA Image and Video Library

2018-01-31

California’s NASA Armstrong Flight Research Center photographer Ken Ulbrich takes photos of Super Blue Blood Moon eclipse making a time-lapse composition of the event on January 31. The total lunar eclipse provided a rare opportunity to capture a supermoon, a blue moon and a lunar eclipse at the same time. A supermoon occurs when the Moon is closer to Earth in its orbit and appearing 14 percent brighter than usual. As the second full moon of the month, this moon is also commonly known as a blue moon, though it will not be blue in appearance. The super blue moon passed through Earth’s shadow and took on a reddish tint, known as a blood moon. This total lunar eclipse occurs when the Sun, Earth, and a full moon form a near-perfect lineup in space. The Moon passes directly behind the Earth into its umbra (shadow).

Searching for Subsurface Lunar Water Ice using a Nuclear-Powered Rover

NASA Astrophysics Data System (ADS)

Randolph, James E.; Abelson, Robert D.; Oxnevad, Knut I.; Shirley, James H.

2005-02-01

The Vision for Space Exploration has identified the Earth's moon as a future destination for human explorers as a stepping-stone for further manned deep space exploration. The feasibility of building and maintaining a human presence on the moon could be directly related to whether in-situ resources, especially water ice, can be obtained and utilized by astronauts. With the recent success of both Mars Exploration Rovers (MERs), it is clear that a lunar rover could be a desirable platform with which to search for evidence of lunar water prior to the arrival of astronauts. However, since surface water can only exist in permanently shadowed areas of the moon (i.e., deep craters near the poles), conventionally powered rovers would not be practical for exploring these areas for extended periods. Thus, a study was performed to assess the feasibility of a lunar rover mission enabled by small radioisotope power systems (RPS), i.e., systems that use single GPHSs. Small RPSs, the feasibility of which has been looked at by the Department of Energy, would be capable of providing sufficient electrical and thermal power to allow scientific measurements and operations of a small rover on the floor of dark lunar craters. A conceptual study was completed that considered the science instruments that could be accommodated on a MER-type rover using RPS power. To investigate the subsurface characteristics of the crater floor, a pulsed gamma ray/neutron spectrometer and a ground-penetrating radar would be used. Also, a drill would provide core samples from a depth of 1 meter. A rover architecture consistent with MER capabilities included a mast with panoramic cameras and navigation cameras as well as an instrument deployment device (IDD) that allowed direct contact between the instrument head and surface materials to be measured. Because the crater floor is eternally dark, artificial illumination must be used for both landing and roving operations. The rover design included of dual headlights that would be operated during visual imaging observations. During the landing approach, the lander would use a laser imaging technique to image the approaching surface and react to that image to avoid hazards. The baseline rover concept used four GPHS power sources for a total of about 50 We in conjunction with a 25 A hr battery to supply power during peak loads. A detailed analysis of energy usage for various operational scenarios (e.g. roving, science instrument operations, and telecommunications) was completed using an elaborate power simulation tool. The results show that very demanding activities are possible on a daily basis while maintaining the battery charging.

An Eye on Mimas: Endo- and Exogenic Effects on the Surface Evolution of Mimas (Invited)

NASA Astrophysics Data System (ADS)

Schenk, P.

2010-12-01

The first (Cassini orbiter-based) global mapping, color and topographic maps of the innermost of Saturn’s classical midsize icy moons have radically changed our Voyager-based perspectives. Geologically, the 125x145-km-wide, ~12-km-deep Herschel impact crater still dominates the moon. Recent observations confirm this crater in essentially unrelaxed, and is not ancient (possibly less than 1 Gyr). The crater population in the region antipodal to Herschel is now seen to have depths less than half that of normal craters and a disorganized topographic signature. This is provisionally interpreted as evidence for seismic disruption similar to that seen for Caloris Basin on Mercury. A global network of grooves (first detected by Voyager) has been mapped. These are 2 to 3 km deep and appear to be located preferentially in equatorial regions (pending north polar mapping). Many of these grooves may be radial to Herschel although they could also represent extensional cracks due to orbital contraction. The colors of Mimas are dominated E-ring dust deposition on the trailing hemisphere and by the recently discovered (Schenk et al., 2009) equatorial lens extending across the entire leading hemisphere. This lens is distinctly bright in the UV (~0l34 micron) and thus bluish in color and extends from ~30 S to 30 N at its maximum width in the center of the hemisphere. This pattern is very similar to that observed (originally by Voyager) on Tethys. Although the Mimas Equatorial Band (MEB) extends further north in latitude, it is actually narrower when measured on the ground. Both features match the surface patterns expected for irradiation of the surface by incident very energetic MeV electrons that drift in a direction opposite to the plasma flow. These electrons spiral in and preferentially impact the leading hemispheres. Their flux is strongest in the inner Saturn system, explaining the absence of banding on the more distant moons. Enceladus itself is shielded by the densest part of the E-ring, in which it resides, and by the ongoing deposition of plume fallout. The mechanism of surface alteration is uncertain but the recent detection by CIRS (Spencer et al., 2010) of a temperature anomaly in spatial association with the bluish MEB indicates that the surface microstructure is being altered in such a way as to significantly change both the UV signature and the thermal inertia. The bands on both Tethys and Mimas thus record the impact of major components of Saturn’s magnetosphere and help confirm their behavior.

76 FR 37641 - Safety Zone; Independence Day Fireworks Celebration for the City of Half Moon Bay, Half Moon Bay, CA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

...-AA00 Safety Zone; Independence Day Fireworks Celebration for the City of Half Moon Bay, Half Moon Bay... temporary safety zone in the navigable waters of Half Moon Bay, off of Pillar Point Harbor beach, Half Moon Bay, CA in support of the Independence Day Fireworks Celebration for the City of Half Moon Bay...

Super Blue Moon Lunar Eclipse

NASA Image and Video Library

2018-01-31

NASA TV provided coverage of Super Blue Moon Lunar Eclipse on Jan. 31. The full moon was the third in a series of “supermoons,” when the Moon is closer to Earth in its orbit -- known as perigee -- and about 14 percent brighter than usual. It was also the second full moon of the month, commonly known as a “blue moon.” As the super blue moon passed through Earth’s shadow, viewers in some locations experienced a total lunar eclipse. While in Earth’s shadow, the moon also took on a reddish tint – which is sometimes referred to as a “blood moon.”

Image is NASA Armstrong Flight Research Center's aircraft hangar that houses the jets and other aircraft with the eclipsed moon overhead during Jan. 31 Super Blue Blood Moon.

NASA Image and Video Library

2018-01-31

California's NASA Armstrong Flight Research Center photographer Carla Thomas takes photos on January 31 of the rare opportunity to capture a supermoon, a blue moon and a lunar eclipse at the same time. A supermoon occurs when the Moon is closer to Earth in its orbit and appearing 14 percent brighter than usual. As the second full moon of the month, this moon is also commonly known as a blue moon, though it will not be blue in appearance. The super blue moon passed through Earth's shadow and took on a reddish tint, known as a blood moon. This total lunar eclipse occurs when the Sun, Earth, and a full moon form a near-perfect lineup in space. The Moon passes directly behind the Earth into its umbra (shadow).

NASA Armstrong Flight Research Center’s communications facility with radar dish and antennas is shown having the eclipsed moon overhead during Jan. 31 Super Blue Blood Moon.

NASA Image and Video Library

2018-01-31

California’s NASA Armstrong Flight Research Center’s photographer Carla Thomas takes photos on January 31 of the rare opportunity to capture a supermoon, a blue moon and a lunar eclipse at the same time. A supermoon occurs when the Moon is closer to Earth in its orbit and appearing 14 percent brighter than usual. As the second full moon of the month, this moon is also commonly known as a blue moon, though it will not be blue in appearance. The super blue moon passed through Earth’s shadow and took on a reddish tint, known as a blood moon. This total lunar eclipse occurs when the Sun, Earth, and a full moon form a near-perfect lineup in space. The Moon passes directly behind the Earth into its umbra (shadow).

a Steady Thermal State for the Earth's Interior

NASA Astrophysics Data System (ADS)

Andrault, D.; Monteux, J.; Le Bars, M.; Samuel, H.

2015-12-01

Large amounts of heat are permanently lost at the surface yielding the classic view of the Earth continuously cooling down. Contrary to this conventional depiction, we propose that the temperature profile in the deep Earth has remained almost constant for the last ~3 billion years (Ga) or more. The core-mantle boundary (CMB) temperature reached the mantle solidus of 4100 (+/-300) K after complete crystallization of the magma ocean not more than 1 Ga after the Moon-forming impact. The CMB remains at a similar temperature today; seismological evidences of ultra-low velocity zones suggest partial melting in the D"-layer and, therefore, a current temperature at, or just below, the mantle solidus. Such a steady thermal state of the CMB temperature excludes thermal buoyancy and compositional convection from being the predominant mechanisms to power the geodynamo over geological time. An alternative mechanism to produce motion in the outer core is mechanical forcing by tidal distortion and planetary precession. The conversion of gravitational and rotational energies of the Earth-Moon-Sun system to core motions could have supplied the lowermost mantle with a variable intensity heat source through geological time, due to the regime of core instabilities and/or changes in the astronomical forces. This variable heat source could explain the dramatic volcanic events that occurred in the Earth's history.

The small-comet hypothesis: An upper limit to the current impact rate on the moon

NASA Astrophysics Data System (ADS)

Grier, Jennifer A.; McEwen, Alfred S.

Frank et al. [1986b] and Frank and Sigwarth [1993] hypothesized the intense bombardment of the terrestrial atmosphere by small comets. Their model requires that the Moon is impacted by small comets (107-108 g) at a rate of almost one per minute. We calculate that an object of this mass, even with an exceedingly low density and relatively low velocity, will nevertheless produce a crater at least 50 m in diameter. These craters will excavate immature lunar soil and produce a very bright spot with a diameter of at least 150 m. If low-density comets exist that might not create deep craters [O'Keefe and Ahrens, 1982], they will nevertheless disturb the regolith sufficiently to create detectable bright spots. If the small-comet hypothesis is correct then the near-global lunar imaging returned by Clementine in 1994 should reveal ∼107 bright spots in locations where craters are not present in images acquired in the 1960's and early 1970's. We find no new bright spots in a carefully-studied area of 5.2×104 km², so an upper limit to the current cratering rate by small comets is 33/yr, ∼104 below that expected if the small-comet hypothesis were valid.

Strategic Implications of Human Exploration of Near-Earth Asteroids

NASA Technical Reports Server (NTRS)

Drake, Bret G.

2011-01-01

The current United States Space Policy [1] as articulated by the White House and later confirmed by the Congress [2] calls for [t]he extension of the human presence from low-Earth orbit to other regions of space beyond low-Earth orbit will enable missions to the surface of the Moon and missions to deep space destinations such as near-Earth asteroids and Mars. Human exploration of the Moon and Mars has been the focus of numerous exhaustive studies and planning, but missions to Near-Earth Asteroids (NEAs) has, by comparison, garnered relatively little attention in terms of mission and systems planning. This paper examines the strategic implications of human exploration of NEAs and how they can fit into the overall exploration strategy. This paper specifically addresses how accessible NEAs are in terms of mission duration, technologies required, and overall architecture construct. Example mission architectures utilizing different propulsion technologies such as chemical, nuclear thermal, and solar electric propulsion were formulated to determine resulting figures of merit including number of NEAs accessible, time of flight, mission mass, number of departure windows, and length of the launch windows. These data, in conjunction with what we currently know about these potential exploration targets (or need to know in the future), provide key insights necessary for future mission and strategic planning.

High Degree and Order Gravity Fields of the Moon Derived from GRAIL Data

NASA Technical Reports Server (NTRS)

Lemoine, F. G.; Goossens, S. J.; Sabaka, T. J.; Nicholas, J. B.; Mazarico, E.; Rowlands, D. D.; Loomis, B. D.; Chinn, D. S.; Caprette, D. S.; McCarthy, J. J.;