Preliminary feasibility assessment for Earth-to-space electromagnetic (Railgun) launchers

NASA Technical Reports Server (NTRS)

Rice, E. E.; Miller, L. A.; Earhart, R. W.

1982-01-01

An Earth to space electromagnetic (railgun) launcher (ESRL) for launching material into space was studied. Potential ESRL applications were identified and initially assessed to formulate preliminary system requirements. The potential applications included nuclear waste disposal in space, Earth orbital applications, deep space probe launchers, atmospheric research, and boost of chemical rockets. The ESRL system concept consisted of two separate railgun launcher tubes (one at 20 deg from the horizontal for Earth orbital missions, the other vertical for solar system escape disposal missions) powered by a common power plant. Each 2040 m launcher tube is surrounded by 10,200 homopolar generator/inductor units to transmit the power to the walls. Projectile masses are 6500 kg for Earth orbital missions and 2055 kg for nuclear waste disposal missions. For the Earth orbital missions, the projectile requires a propulsion system, leaving an estimated payload mass of 650 kg. For the nuclear waste disposal in space mission, the high level waste mass was estimated at 250 kg. This preliminary assessment included technical, environmental, and economic analyses.

A PRELIMINARY JUPITER MODEL

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

Hubbard, W. B.; Militzer, B.

In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen–helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second-more » and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen–helium-rich envelope with approximately three times solar metallicity.« less

Preliminary Design Considerations for Access and Operations in Earth-Moon L1/L2 Orbits

NASA Technical Reports Server (NTRS)

Folta, David C.; Pavlak, Thomas A.; Haapala, Amanda F.; Howell, Kathleen C.

2013-01-01

Within the context of manned spaceflight activities, Earth-Moon libration point orbits could support lunar surface operations and serve as staging areas for future missions to near-Earth asteroids and Mars. This investigation examines preliminary design considerations including Earth-Moon L1/L2 libration point orbit selection, transfers, and stationkeeping costs associated with maintaining a spacecraft in the vicinity of L1 or L2 for a specified duration. Existing tools in multi-body trajectory design, dynamical systems theory, and orbit maintenance are leveraged in this analysis to explore end-to-end concepts for manned missions to Earth-Moon libration points.

The Near Earth Object Scout Spacecraft: A Low Cost Approach to in-situ Characterization of the NEO Population

NASA Technical Reports Server (NTRS)

Koontz, Steven L.; Condon, Gerald; Graham, Lee; Bevilacqua, Ricardo

2014-01-01

In this paper we describe a micro/nano satellite spacecraft and a supporting mission profile and architecture designed to enable preliminary in-situ characterization of a significant number of Near Earth Objects (NEOs) at reasonable cost. The spacecraft will be referred to as the NEO Scout. NEO Scout spacecraft are to be placed in GTO, GEO, or cis-lunar space as secondary payloads on launch vehicles headed for GTO or beyond and will begin their mission after deployment from the launcher. A distinguishing key feature of the NEO scout system is to design the mission timeline and spacecraft to rendezvous with and land on the target NEOs during close approach to the Earth-Moon system using low-thrust/high- impulse propulsion systems. Mission feasibility and preliminary design analysis are presented along with detailed trajectory calculations. The use of micro/nano satellites in low-cost interplanetary exploration is attracting increasing attention and is the subject of several annual workshops and published design studies (1-4). The NEO population consists of those asteroids and short period comets orbiting the Sun with a perihelion of 1.3 astronomical units or less (5-8). As of July 30, 2013 10065 Near-Earth objects have been discovered. The spin rate, mass, density, surface physical (especially mechanical) properties, composition, and mineralogy of the vast majority of these objects are highly uncertain and the limited available telescopic remote sensing data imply a very diverse population (5-8). In-situ measurements by robotic spacecraft are urgently needed to provide the characterization data needed to support hardware and mission design for more ambitious human and robotic NEO operations. Large numbers of NEOs move into close proximity with the Earth-Moon system every year (9). The JPL Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) (10) has produced detailed mission profile and delta V requirements for various NEO missions ranging from 30 to 420 days in duration and assuming chemical propulsion. Similar studies have been reported assuming high power electric propulsion for manned NEO rendezvous missions (11). The delta V requirement breakdown and mission profile data from references 10 and 11 are used as a basis for sizing the NEO Scout spacecraft and for conducting preliminary feasibility assessments using the Tsiokolvsky rocket equation, a (worst-case) delta V requirement of 10 km/sec, and a maximum spacecraft dry mass of 20 kg. Using chemical propellant for a 10 km/sec delta V drives spacecraft wet mass well above 300 kg so that chemical propulsion is a non-starter for the proposed mission profile and spacecraft wet mass limits. In contrast, a solar electric propulsion system needs only 8 kg of Xe propellant to accelerate the spacecraft to 10 km/sec in 163 days with 0.02 N of thrust and 500 W of power from1.6 sq m of 29% efficient solar panels. In a second example, accelerating a 4 kg payload to 7 km/sec over 180 days requires about 6.7 kg of propellant and 1.2 kg of solar panels (12 kg total spacecraft wet mass).

Bioresearch Module Design Definition and Space Shuttle Vehicle Integration Study. Volume 1: Basic Report

NASA Technical Reports Server (NTRS)

Lang, A. L., Jr.

1971-01-01

Preliminary designs of the Bioexplorer spacecraft, developed in an earlier study program, are analyzed and updated to conform to a new specification which includes use of both the Scout and the space shuttle vehicle for launch. The updated spacecraft is referred to as bioresearch module. It is capable of supporting a variety of small biological experiments in near-earth and highly elliptical earth orbits. The baseline spacecraft design is compatible with the Scout launch vehicle. Inboard profile drawings, weight statements, interface drawings, and spacecraft parts and aerospace ground equipment lists are provided to document the design. The baseline design was analyzed to determine the design and cost impact of a set of optional features. These include reduced experiment power and thermal load, addition of an experiment television monitor, and replacement of VHF with S-band communications. The impact of these options on power required, weight change and cost is defined.

Environmental assessment for the satellite power system concept development and evaluation program: nonmicrowave health and ecological effects

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

White, M R

1980-11-01

A Concept Development and Evaluation Program is being carried out for a proposed Satellite Power System (SPS). For purposes of this evaluation, a preliminary reference system has been developed. SPS, as described in the reference system, would collect solar energy on satellites in geosychronous orbit in space. The energy would be converted to microwaves and beamed to an earth-receiving antenna (rectenna). One task in the environmental part of the program is the assessment of the nonmicrowave effects on health and the environment. These effects would result from all phases of SPS development and operation. This report covers the current knowledgemore » regarding these effects, and is based on the reference system. The assessment is summarized as to scope, methodology, impacts of terrestrial development, launch and recovery of spacecraft, space activities (including health effects of the space environment, ionizing radiation, electromagnetic exposure, spacecraft charging and environmental interactions, occupational hazards, etc.) and construction and operation of rectenna (ground receiving station).« less

Lunar Flight Study Series: Volume 4. Preliminary Investigation of the Astronautics of Earth - Moon Transits

NASA Technical Reports Server (NTRS)

Braud, Nolan J.

1963-01-01

Preliminary information on flight profiles, velocity budgets and launch windows for Apollo and Support Vehicle flights is presented in this report. A newly conceived method of establishing a flight mechanical classification of the earth-moon transits is discussed. The results are empirical and are designed to contribute to the mission mode selection.

Preliminary findings on water quality of ricing lakes on White Earth Reservation, MN

USDA-ARS?s Scientific Manuscript database

Wild rice is a cultural and economic staple of the Anishinaabe People of White Earth. Changes in land use within the watershed may impact the water quality of ricing lakes on the reservation. The purpose of this discussion is to report the preliminary findings of water quality analysis of samples ta...

Report of the panel on earth rotation and reference frames, section 7

NASA Technical Reports Server (NTRS)

Dickey, Jean O.; Dickman, Steven R.; Eubanks, Marshall T.; Feissel, Martine; Herring, Thomas A.; Mueller, Ivan I.; Rosen, Richard D.; Schutz, Robert E.; Wahr, John M.; Wilson, Charles R.

1991-01-01

Objectives and requirements for Earth rotation and reference frame studies in the 1990s are discussed. The objectives are to observe and understand interactions of air and water with the rotational dynamics of the Earth, the effects of the Earth's crust and mantle on the dynamics and excitation of Earth rotation variations over time scales of hours to centuries, and the effects of the Earth's core on the rotational dynamics and the excitation of Earth rotation variations over time scales of a year or longer. Another objective is to establish, refine and maintain terrestrial and celestrial reference frames. Requirements include improvements in observations and analysis, improvements in celestial and terrestrial reference frames and reference frame connections, and improved observations of crustal motion and mass redistribution on the Earth.

Preliminary flight test results from the advanced photovoltaic experiment

NASA Technical Reports Server (NTRS)

Brinker, David J.; Hickey, John R.

1990-01-01

The Advanced Photovoltaic Experiment is a space flight test designed to provide reference cell standards for photovoltaic measurement as well as to investigate the solar spectrum and the effect of the space environment on solar cells. After a flight of 69 months in low earth orbit as part of the Long Duration Exposure Facility set of experiments, it was retrieved in January, 1990. The electronic data acquisition system functioned as designed, measuring and recording cell performance data over the first 358 days of flight, limited by battery lifetime. Significant physical changes are also readily apparent, including erosion of front surface paint, micrometeoroid and debris catering and contamination.

Preliminary results from the advanced photovoltaic experiment flight test

NASA Technical Reports Server (NTRS)

Brinker, David J.; Hart, Russell E., Jr.; Hickey, John R.

1990-01-01

The Advanced Photovoltaic Experiment is a space flight test designed to provide reference cell standards for photovoltaic measurement as well as to investigate the solar spectrum and the effect of the space environment on solar cells. After a flight of 69 months in low earth orbit as part of the Long Duration Exposure Facility set of experiments, it was retrieved in January, 1990. The electronic data acquisition system functioned as designed, measuring and recording cell performance data over the first 358 days of flight; limited by battery lifetime. Significant physical changes are also readily apparent, including erosion of front surface paint, micrometeoroid and debris catering and contamination.

On the estimation of physical height changes using GRACE satellite mission data - A case study of Central Europe

NASA Astrophysics Data System (ADS)

Godah, Walyeldeen; Szelachowska, Małgorzata; Krynski, Jan

2017-12-01

The dedicated gravity satellite missions, in particular the GRACE (Gravity Recovery and Climate Experiment) mission launched in 2002, provide unique data for studying temporal variations of mass distribution in the Earth's system, and thereby, the geometry and the gravity fi eld changes of the Earth. The main objective of this contribution is to estimate physical height (e.g. the orthometric/normal height) changes over Central Europe using GRACE satellite mission data as well as to analyse them and model over the selected study area. Physical height changes were estimated from temporal variations of height anomalies and vertical displacements of the Earth surface being determined over the investigated area. The release 5 (RL05) GRACE-based global geopotential models as well as load Love numbers from the Preliminary Reference Earth Model (PREM) were used as input data. Analysis of the estimated physical height changes and their modelling were performed using two methods: the seasonal decomposition method and the PCA/ EOF (Principal Component Analysis/Empirical Orthogonal Function) method and the differences obtained were discussed. The main fi ndings reveal that physical height changes over the selected study area reach up to 22.8 mm. The obtained physical height changes can be modelled with an accuracy of 1.4 mm using the seasonal decomposition method.

Analysis of Rare Earth Elements in Uranium Using Handheld Laser-Induced Breakdown Spectroscopy (HH LIBS)

DOE PAGES

Manard, Benjamin T.; Wylie, E. Miller; Willson, Stephen P.

2018-05-22

In this paper, a portable handheld laser-induced breakdown spectroscopy (HH LIBS) instrument was evaluated as a rapid method to qualitatively analyze rare earth elements in a uranium oxide matrix. This research is motivated by the need for development of a method to perform rapid, at-line chemical analysis in a nuclear facility, particularly to provide a rapid first pass analysis to determine if additional actions or measurements are warranted. This will result in the minimization of handling and transport of radiological and nuclear material and subsequent exposure to their associated hazards. In this work, rare earth elements (Eu, Nd, and Yb)more » were quantitatively spiked into a uranium oxide powder and analyzed by the HH LIBS instrumentation. This method demonstrates the ability to rapidly identify elemental constituents in sub-percent levels in a uranium matrix. Preliminary limits of detection (LODs) were determined with values on the order of hundredths of a percent. Validity of this methodology was explored by employing a National Institute of Standards and Technology (NIST) standard reference materials (SRM) 610 and 612 (Trace Elements in Glass). Finally, it was determined that the HH LIBS method was able to clearly discern the rare earths elements of interest in the glass or uranium matrices.« less

Analysis of Rare Earth Elements in Uranium Using Handheld Laser-Induced Breakdown Spectroscopy (HH LIBS)

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

Manard, Benjamin T.; Wylie, E. Miller; Willson, Stephen P.

In this paper, a portable handheld laser-induced breakdown spectroscopy (HH LIBS) instrument was evaluated as a rapid method to qualitatively analyze rare earth elements in a uranium oxide matrix. This research is motivated by the need for development of a method to perform rapid, at-line chemical analysis in a nuclear facility, particularly to provide a rapid first pass analysis to determine if additional actions or measurements are warranted. This will result in the minimization of handling and transport of radiological and nuclear material and subsequent exposure to their associated hazards. In this work, rare earth elements (Eu, Nd, and Yb)more » were quantitatively spiked into a uranium oxide powder and analyzed by the HH LIBS instrumentation. This method demonstrates the ability to rapidly identify elemental constituents in sub-percent levels in a uranium matrix. Preliminary limits of detection (LODs) were determined with values on the order of hundredths of a percent. Validity of this methodology was explored by employing a National Institute of Standards and Technology (NIST) standard reference materials (SRM) 610 and 612 (Trace Elements in Glass). Finally, it was determined that the HH LIBS method was able to clearly discern the rare earths elements of interest in the glass or uranium matrices.« less

Analysis of Rare Earth Elements in Uranium Using Handheld Laser-Induced Breakdown Spectroscopy (HH LIBS).

PubMed

Manard, Benjamin T; Wylie, E Miller; Willson, Stephen P

2018-01-01

A portable handheld laser-induced breakdown spectroscopy (HH LIBS) instrument was evaluated as a rapid method to qualitatively analyze rare earth elements in a uranium oxide matrix. This research is motivated by the need for development of a method to perform rapid, at-line chemical analysis in a nuclear facility, particularly to provide a rapid first pass analysis to determine if additional actions or measurements are warranted. This will result in the minimization of handling and transport of radiological and nuclear material and subsequent exposure to their associated hazards. In this work, rare earth elements (Eu, Nd, and Yb) were quantitatively spiked into a uranium oxide powder and analyzed by the HH LIBS instrumentation. This method demonstrates the ability to rapidly identify elemental constituents in sub-percent levels in a uranium matrix. Preliminary limits of detection (LODs) were determined with values on the order of hundredths of a percent. Validity of this methodology was explored by employing a National Institute of Standards and Technology (NIST) standard reference materials (SRM) 610 and 612 (Trace Elements in Glass). It was determined that the HH LIBS method was able to clearly discern the rare earths elements of interest in the glass or uranium matrices.

Preliminary pioneer 10 encounter results from the ames research center plasma analyzer experiment.

PubMed

Wolfe, J H; Collard, H R; Mihalov, J D; Intriligator, D S

1974-01-25

Preliminary results from the Ames Research Center plasma analyzer experiment for the Pioneer 10 Jupiter encounter indicate that Jupiter has a detached bow shock and magnetopause similar to the case at Earth but much larger in spatial extent. In contrast to Earth, Jupiter's outer magnetosphere appears to be highly inflated by thermal plasma and therefore highly responsive in size to changes in solar wind dynamic pressure.

Technology requirements for future Earth-to-geosynchronous orbit transportation systems. Volume 2: Technical results

NASA Technical Reports Server (NTRS)

Caluori, V. A.

1980-01-01

Technologies either critical to performance of offering cost advantages compared to the investment required to bring them to usable confidence levels are identified. A total transportation system is used as an evaluation yardstick. Vehicles included in the system are a single stage to orbit launch vehicle used in a priority cargo role, a matching orbit transfer vehicle, a heavy lift launch vehicle with a low Earth orbit delivery capability of 226, 575 kg, and a matching solar electric cargo orbit transfer vehicle. The system and its reference technology level are consistent with an initial operational capability in 1990. The 15 year mission scenario is based on early space industrialization leading to the deployment of large systems such as power satellites. Life cycle cost benefits in discounted and undiscounted dollars for each vehicle, technology advancement, and the integrated transportation system are calculated. A preliminary functional analysis was made of the operational support requirements for ground based and space based chemical propulsion orbit transfer vehicles.

Molecular parity violation via comets?

PubMed

Meierhenrich, U; Thiemann, W H; Rosenbauer, H

1999-01-01

Recent theoretical and experimental investigations referring to the origin of homochirality are reviewed and integrated into the hitherto known state of the art. Attention is directed to an extraterrestrial scenario, which describes the interaction of circularly polarized synchrotron radiation with interstellar organic matter. Following this Bonner-Rubenstein hypothesis, optically active molecules could be transferred to Earth via comets. We plan to identify any enantiomeric enhancement in organic molecules of the cometary matter in situ. The present preliminary experimental study intends to optimize gas-chromatographic conditions for the separation of racemates into their enantiomer constituents on the surface of the comet 46P/Wirtanen. Underivatized racemic pairs of alcohols, diols, and phenyl-substituted amines have been separated with the help of a stationary trifluoroacetyl-cyclodextrin phase. We are still developing a technique that will enable us to detect any enantiomeric enhancement of specific simple organic molecules both in cometary or Martian matter in situ and in meteorites found on Earth. Copyright 1999 Wiley-Liss, Inc.

MSFC integrated experiments preliminary report. [for the Skylab program

NASA Technical Reports Server (NTRS)

1974-01-01

Skylab experiments are described and their preliminary results are reported. The types of experiments described include medical, earth resources, space physics, space manufacturing, and spacecraft design.

Tidal Heating in Multilayered Terrestrial Exoplanets

NASA Technical Reports Server (NTRS)

Henning, Wade G.; Hurford, Terry

2014-01-01

The internal pattern and overall magnitude of tidal heating for spin-synchronous terrestrial exoplanets from 1 to 2.5 R(sub E) is investigated using a propagator matrix method for a variety of layer structures. Particular attention is paid to ice-silicate hybrid super-Earths, where a significant ice mantle is modeled to rest atop an iron-silicate core, and may or may not contain a liquid water ocean. We find multilayer modeling often increases tidal dissipation relative to a homogeneous model, across multiple orbital periods, due to the ability to include smaller volume low viscosity regions, and the added flexure allowed by liquid layers. Gradations in parameters with depth are explored, such as allowed by the Preliminary Earth Reference Model. For ice-silicate hybrid worlds, dramatically greater dissipation is possible beyond the case of a silicate mantle only, allowing non-negligible tidal activity to extend to greater orbital periods than previously predicted. Surface patterns of tidal heating are found to potentially be useful for distinguishing internal structure. The influence of ice mantle depth and water ocean size and position are shown for a range of forcing frequencies. Rates of orbital circularization are found to be 10-100 times faster than standard predictions for Earth-analog planets when interiors are moderately warmer than the modern Earth, as well as for a diverse range of ice-silicate hybrid super-Earths. Circularization rates are shown to be significantly longer for planets with layers equivalent to an ocean-free modern Earth, as well as for planets with high fractions of either ice or silicate melting.

Geophysical parameters from the analysis of laser ranging to starlette

NASA Technical Reports Server (NTRS)

Schutz, B. E.; Shum, C. K.

1987-01-01

Starlette Satellite Laser Ranging (SLR) data were used, along with several other satellite data sets, for the solution of a preliminary gravity field model for TOPEX, PTGF1. A further improvement in the earth gravity model was accomplished using data collected by 12 satellites to solve another preliminary gravity model for TOPEX, designated PTGF2. The solution for the Earth Rotation Parameter (ERP) was derived from the analysis of SLR data to Starlette during the MERIT Campaign. Starlette orbits in 1976 and 1983 were analyzed for the mapping of the tidal response of the earth. Publications and conference presentations pertinent to research are listed.

First-principles prediction of Si-doped Fe carbide as one of the possible constituents of Earth's inner core

NASA Astrophysics Data System (ADS)

Das, Tilak; Chatterjee, Swastika; Ghosh, Sujoy; Saha-Dasgupta, Tanusri

2017-09-01

We perform a computational study based on first-principles calculations to investigate the relative stability and elastic properties of the doped and undoped Fe carbide compounds at 200-364 GPa. We find that upon doping a few weight percent of Si impurities at the carbon sites in Fe7C3 carbide phases, the values of Poisson's ratio and density increase while VP, and VS decrease compared to their undoped counterparts. This leads to marked improvement in the agreement of seismic parameters such as P wave and S wave velocity, Poisson's ratio, and density with the Preliminary Reference Earth Model (PREM) data. The agreement with PREM data is found to be better for the orthorhombic phase of iron carbide (o-Fe7C3) compared to hexagonal phase (h-Fe7C3). Our theoretical analysis indicates that Fe carbide containing Si impurities can be a possible constituent of the Earth's inner core. Since the density of undoped Fe7C3 is low compared to that of inner core, as discussed in a recent theoretical study, our proposal of Si-doped Fe7C3 can provide an alternative solution as an important component of the Earth's inner core.

Space exercise and Earth benefits.

PubMed

Macias, Brandon R; Groppo, Eli R; Eastlack, Robert K; Watenpaugh, Donald E; Lee, Stuart M C; Schneider, Suzanne M; Boda, Wanda L; Smith, Scott M; Cutuk, Adnan; Pedowitz, Robert A; Meyer, R Scott; Hargens, Alan R

2005-08-01

The detrimental impact of long duration space flight on physiological systems necessitates the development of exercise countermeasures to protect work capabilities in gravity fields of Earth, Moon and Mars. The respective rates of physiological deconditioning for different organ systems during space flight has been described as a result of data collected during and after missions on the Space Shuttle, International Space Station, Mir, and bed rest studies on Earth. An integrated countermeasure that simulates the body's hydrostatic pressure gradient, provides mechanical stress to the bones and muscles, and stimulates the neurovestibular system may be critical for maintaining health and well being of crew during long-duration space travel, such as a mission to Mars. Here we review the results of our studies to date of an integrated exercise countermeasure for space flight, lower body negative pressure (LBNP) treadmill exercise, and potential benefits of its application to athletic training on Earth. Additionally, we review the benefits of Lower Body Positive Pressure (LBPP) exercise for rehabilitation of postoperative patients. Presented first are preliminary data from a 30-day bed rest study evaluating the efficacy of LBNP exercise as an integrated exercise countermeasure for the deconditioning effects of microgravity. Next, we review upright LBNP exercise as a training modality for athletes by evaluating effects on the cardiovascular system and gait mechanics. Finally, LBPP exercise as a rehabilitation device is examined with reference to gait mechanics and safety in two groups of postoperative patients.

Effect of 3-D heterogeneous-earth on rheology inference of postseismic model following the 2012 Indian Ocean earthquake

NASA Astrophysics Data System (ADS)

Pratama, C.; Ito, T.; Sasajima, R.; Tabei, T.; Kimata, F.; Gunawan, E.; Ohta, Y.; Yamashina, T.; Ismail, N.; Muksin, U.; Maulida, P.; Meilano, I.; Nurdin, I.; Sugiyanto, D.; Efendi, J.

2017-12-01

Postseismic deformation following the 2012 Indian Ocean earthquake has been modeled by several studies (Han et al. 2015, Hu et al. 2016, Masuti et al. 2016). Although each study used different method and dataset, the previous studies constructed a significant difference of earth structure. Han et al. (2015) ignored subducting slab beneath Sumatra while Masuti et al. (2016) neglect sphericity of the earth. Hu et al. (2016) incorporated elastic slab and spherical earth but used uniform rigidity in each layer of the model. As a result, Han et al. (2015) model estimated one order higher Maxwell viscosity than the Hu et al. (2016) and half order lower Kelvin viscosity than the Masuti et al. (2016) model predicted. In the present study, we conduct a quantitative analysis of each heterogeneous geometry and parameter effect on rheology inference. We develop heterogeneous three-dimensional spherical-earth finite element models. We investigate the effect of subducting slab, spherical earth, and three-dimensional earth rigidity on estimated lithosphere-asthenosphere rheology beneath the Indian Ocean. A wide range of viscosity structure from time constant rheology to time dependent rheology was chosen as previous studies have been modeled. In order to evaluate actual displacement, we compared the model to the Global Navigation Satellite System (GNSS) observation. We incorporate the GNSS data from previous studies and introduce new GNSS site as a part of the Indonesian Continuously Operating Reference Stations (InaCORS) located in Sumatra that has not been used in the last analysis. As a preliminary result, we obtained the effect of the spherical earth and elastic slab when we assumed burgers rheology. The model that incorporates the sphericity of the earth needs a one third order lower viscosity than the model that neglects earth curvature. The model that includes elastic slab needs half order lower viscosity than the model that excluding the elastic slab.

Resources and References for Earth Science Teachers

ERIC Educational Resources Information Center

Wall, Charles A.; Wall, Janet E.

1976-01-01

Listed are resources and references for earth science teachers including doctoral research, new textbooks, and professional literature in astronomy, space science, earth science, geology, meteorology, and oceanography. (SL)

Four dimensional studies in earth space

NASA Technical Reports Server (NTRS)

Mather, R. S.

1972-01-01

A system of reference which is directly related to observations, is proposed for four-dimensional studies in earth space. Global control network and polar wandering are defined. The determination of variations in the earth's gravitational field with time also forms part of such a system. Techniques are outlined for the unique definition of the motion of the geocenter, and the changes in the location of the axis of rotation of an instantaneous earth model, in relation to values at some epoch of reference. The instantaneous system referred to is directly related to a fundamental equation in geodynamics. The reference system defined would provide an unambiguous frame for long period studies in earth space, provided the scale of the space were specified.

75 FR 53963 - Iron Mask Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

...-long upper dam made of either zoned earth and rockfill or concrete-face earth and rockfill; (2) a 50-foot-high, 950-foot-long earth-filled upper saddle dike A; (3) a 20-foot-high, 400-foot-long earth-filled upper saddle dike B; (4) a 40-foot-high, 6,559-foot-long lower embankment made of zoned earth or...

Seismic Wave Velocity in Earth's Shallow Core

NASA Astrophysics Data System (ADS)

Alexandrakis, C.; Eaton, D. W.

2008-12-01

Studies of the outer core indicate that it is composed of liquid Fe and Ni alloyed with a ~10% fraction of light elements such as O, S or Si. Recently, unusual features, such as sediment accumulation, immiscible fluid layers or stagnant convection, have been predicted in the shallow core region. Secular cooling and compositional buoyancy drive vigorous convection that sustains the geodynamo, although critical details of light-element composition and thermal regime remain uncertain. Seismic velocity models can provide important constraints on the light element composition, however global reference models, such as Preliminary Reference Earth Model (PREM), IASP91 and AK135 vary significantly in the 200 km below the core-mantle boundary. Past studies of the outermost core velocity structure have been hampered by traveltime uncertainties due to lowermost mantle heterogeneities. The recently published Empirical Transfer Function (ETF) method has been shown to reduce the uncertainty using a waveform stacking approach to improve global observations of SmKS teleseismic waves. Here, we apply the ETF method to achieve a precise top-of-core velocity measurement of 8.05 ± 0.03 km/s. This new model accords well with PREM. Since PREM is based on the adiabatic form of the Adams-Williamson equation, it assumes a well mixed (i.e. homogeneous) composition. This result suggests a lack of heterogeneity in the outermost core due to layering or stagnant convection.

SWCX Emission from the Helium Focusing Cone - Preliminary Results

NASA Technical Reports Server (NTRS)

Snowden, S. L.; Kuntz, K. D.; Collier, M. R.

2008-01-01

Preliminary results from an XMM-Newton campaign to study solar wind charge exchange (SWCX) emission from the heliospheric focusing cone of interstellar helium are presented. The detections of enhanced O VII and O VIII emission from the cone are at the 2(sigma) and 4(sigma) levels. The solar wind charge exchange (SWCX) emission in the heliosphere not associated with distinct objects (e.g., comets and planets including exospheric material in and near Earth s magnetosheath) is proportional to the flux of the solar wind and the space density of neutral material. The neutral material originates in the interstellar medium (ISM) and passes through the solar system due to the relative motion of the Sun and the ISM. The flow of the neutral material through the solar system is strongly perturbed by the Sun both by gravity and by radiation pressure. Because of the relative radiative scattering cross sections and the effect of solar gravitation the density of interstellar hydrogen near the Sun is reduced while interstellar helium is gravitationally focused. This creates a helium focusing cone downstream of the Sun [e.g., 1, and references therein].

What is driving rates of social policy preliminary references to the CJEU? Evidence from the United Kingdom and France

PubMed Central

Sigafoos, Jennifer

2013-01-01

Preliminary references to the Court of Justice for the European Union are unevenly distributed across the EU, creating differing access to justice for European citizens. This study presents case studies of the UK and France, exploring factors affecting rates of social policy preliminary references from 1996–2009. The UK had a rate twice that of France. What accounts for this difference? Analysis of documentary evidence and 25 expert interviews help to explain the differing rates. Themes were related to policy, structural factors and the agency of actors. In the UK, policy themes are the free movement of persons and the ‘Right to Reside’ test. Legal aid and legal NGOs help individuals access the Court and drive test case strategies. In France, a high degree of dualisation in the welfare state creates an insider/outsider dynamic. Coupled with the resistance of courts and a lack of comparable actors to drive preliminary references, this contributes to a lower rate of references. PMID:23565042

Preliminary design study for an atomospheric science facility

NASA Technical Reports Server (NTRS)

Hutchison, R.

1972-01-01

The activities and results of the Atmospheric Science Facility preliminary design study are reported. The objectives of the study were to define the scientific goals, to determine the range of experiment types, and to develop the preliminary instrument design requirements for a reusable, general purpose, optical research facility for investigating the earth's atmosphere from a space shuttle orbital vehicle.

Geosynchronous earth orbit/low earth orbit space object inspection and debris disposal: A preliminary analysis using a carrier satellite with deployable small satellites

NASA Astrophysics Data System (ADS)

Crockett, Derick

Detailed observations of geosynchronous satellites from earth are very limited. To better inspect these high altitude satellites, the use of small, refuelable satellites is proposed. The small satellites are stationed on a carrier platform in an orbit near the population of geosynchronous satellites. A carrier platform equipped with deployable, refuelable SmallSats is a viable option to inspect geosynchronous satellites. The propellant requirement to transfer to a targeted geosynchronous satellite, perform a proximity inspection mission, and transfer back to the carrier platform in a nearby orbit is determined. Convex optimization and traditional optimization techniques are explored, determining minimum propellant trajectories. Propellant is measured by the total required change in velocity, delta-v. The trajectories were modeled in a relative reference frame using the Clohessy-Wiltshire equations. Mass estimations for the carrier platform and the SmallSat were determined by using the rocket equation. The mass estimates were compared to the mass of a single, non-refuelable satellite performing the same geosynchronous satellite inspection missions. From the minimum delta-v trajectories and the mass analysis, it is determined that using refuelable SmallSats and a carrier platform in a nearby orbit can be more efficient than using a single non-refuelable satellite to perform multiple geosynchronous satellite inspections.

The Long-Wave Infrared Earth Image as a Pointing Reference for Deep-Space Optical Communications

NASA Astrophysics Data System (ADS)

Biswas, A.; Piazzolla, S.; Peterson, G.; Ortiz, G. G.; Hemmati, H.

2006-11-01

Optical communications from space require an absolute pointing reference. Whereas at near-Earth and even planetary distances out to Mars and Jupiter a laser beacon transmitted from Earth can serve as such a pointing reference, for farther distances extending to the outer reaches of the solar system, the means for meeting this requirement remains an open issue. We discuss in this article the prospects and consequences of utilizing the Earth image sensed in the long-wave infrared (LWIR) spectral band as a beacon to satisfy the absolute pointing requirements. We have used data from satellite-based thermal measurements of Earth to synthesize images at various ranges and have shown the centroiding accuracies that can be achieved with prospective LWIR image sensing arrays. The nonuniform emissivity of Earth causes a mispointing bias error term that exceeds a provisional pointing budget allocation when using simple centroiding algorithms. Other issues related to implementing thermal imaging of Earth from deep space for the purposes of providing a pointing reference are also reported.

ASPEC: Solar power satellite

NASA Technical Reports Server (NTRS)

1991-01-01

The solar power satellite (SPS) will provide a clean, reliable source of energy for large-scale consumption. The system will use satellites in geostationary orbits around the Earth to capture the Sun's energy. The intercepted sunlight will be converted to laser beam energy that can be transmitted to the Earth's surface. Ground systems on the Earth will convert the transmissions from space into electric power. The preliminary design for the SPS consists of one satellite in orbit around the Earth transmitting energy to a single ground station. The SPS design uses multilayer solar cell technology arranged on a 20 km squared planar array to intercept sunlight and convert it to an electric voltage. Power conditioning devices then send the electricity to a laser, which transmits the power to the surface of the Earth. A ground station will convert the beam into electricity. Typically, a single SPS will supply 5 GW of power to the ground station. Due to the large mass of the SPS, about 41 million kg, construction in space is needed in order to keep the structural mass low. The orbit configuration for this design is to operate a single satellite in geosynchronous orbit (GEO). The GEO allows the system to be positioned above a single receiving station and remain in sunlight 99 percent of the time. Construction will take place in low Earth orbit (LEO); array sections, 20 in total, will be sailed on solar wind out to the GEO location in 150 days. These individual transportation sections are referred to as solar sailing array panels (SSAP's). The primary truss elements used to support the array are composed of composite tubular members in a pentahedral arrangement. Smart segments consisting of passive and active damping devices will increase the control of dynamic SPS modes.

Defining Top-of-Atmosphere Flux Reference Level for Earth Radiation Budget Studies

NASA Technical Reports Server (NTRS)

Loeb, N. G.; Kato, S.; Wielicki, B. A.

2002-01-01

To estimate the earth's radiation budget at the top of the atmosphere (TOA) from satellite-measured radiances, it is necessary to account for the finite geometry of the earth and recognize that the earth is a solid body surrounded by a translucent atmosphere of finite thickness that attenuates solar radiation differently at different heights. As a result, in order to account for all of the reflected solar and emitted thermal radiation from the planet by direct integration of satellite-measured radiances, the measurement viewing geometry must be defined at a reference level well above the earth s surface (e.g., 100 km). This ensures that all radiation contributions, including radiation escaping the planet along slant paths above the earth s tangent point, are accounted for. By using a field-of- view (FOV) reference level that is too low (such as the surface reference level), TOA fluxes for most scene types are systematically underestimated by 1-2 W/sq m. In addition, since TOA flux represents a flow of radiant energy per unit area, and varies with distance from the earth according to the inverse-square law, a reference level is also needed to define satellite-based TOA fluxes. From theoretical radiative transfer calculations using a model that accounts for spherical geometry, the optimal reference level for defining TOA fluxes in radiation budget studies for the earth is estimated to be approximately 20 km. At this reference level, there is no need to explicitly account for horizontal transmission of solar radiation through the atmosphere in the earth radiation budget calculation. In this context, therefore, the 20-km reference level corresponds to the effective radiative top of atmosphere for the planet. Although the optimal flux reference level depends slightly on scene type due to differences in effective transmission of solar radiation with cloud height, the difference in flux caused by neglecting the scene-type dependence is less than 0.1%. If an inappropriate TOA flux reference level is used to define satellite TOA fluxes, and horizontal transmission of solar radiation through the planet is not accounted for in the radiation budget equation, systematic errors in net flux of up to 8 W/sq m can result. Since climate models generally use a plane-parallel model approximation to estimate TOA fluxes and the earth radiation budget, they implicitly assume zero horizontal transmission of solar radiation in the radiation budget equation, and do not need to specify a flux reference level. By defining satellite-based TOA flux estimates at a 20-km flux reference level, comparisons with plane-parallel climate model calculations are simplified since there is no need to explicitly correct plane-parallel climate model fluxes for horizontal transmission of solar radiation through a finite earth.

Earth-strength magnetic field affects the rheotactic threshold of zebrafish swimming in shoals.

PubMed

Cresci, Alessandro; De Rosa, Rosario; Putman, Nathan F; Agnisola, Claudio

2017-02-01

Rheotaxis, the unconditioned orienting response to water currents, is a main component of fish behavior. Rheotaxis is achieved using multiple sensory systems, including visual and tactile cues. Rheotactic orientation in open or low-visibility waters might also benefit from the stable frame of reference provided by the geomagnetic field, but this possibility has not been explored before. Zebrafish (Danio rerio) form shoals living in freshwater systems with low visibility, show a robust positive rheotaxis, and respond to geomagnetic fields. Here, we investigated whether a static magnetic field in the Earth-strength range influenced the rheotactic threshold of zebrafish in a swimming tunnel. The direction of the horizontal component of the magnetic field relative to water flow influenced the rheotactic threshold of fish as part of a shoal, but not of fish tested alone. Results obtained after disabling the lateral line of shoaling individuals with Co 2+ suggest that this organ system is involved in the observed magneto-rheotactic response. These findings constitute preliminary evidence that magnetic fields influence rheotaxis and suggest new avenues for further research. Copyright © 2016 Elsevier Inc. All rights reserved.

Definition and Proposed Realization of the International Height Reference System (IHRS)

NASA Astrophysics Data System (ADS)

Ihde, Johannes; Sánchez, Laura; Barzaghi, Riccardo; Drewes, Hermann; Foerste, Christoph; Gruber, Thomas; Liebsch, Gunter; Marti, Urs; Pail, Roland; Sideris, Michael

2017-05-01

Studying, understanding and modelling global change require geodetic reference frames with an order of accuracy higher than the magnitude of the effects to be actually studied and with high consistency and reliability worldwide. The International Association of Geodesy, taking care of providing a precise geodetic infrastructure for monitoring the Earth system, promotes the implementation of an integrated global geodetic reference frame that provides a reliable frame for consistent analysis and modelling of global phenomena and processes affecting the Earth's gravity field, the Earth's surface geometry and the Earth's rotation. The definition, realization, maintenance and wide utilization of the International Terrestrial Reference System guarantee a globally unified geometric reference frame with an accuracy at the millimetre level. An equivalent high-precision global physical reference frame that supports the reliable description of changes in the Earth's gravity field (such as sea level variations, mass displacements, processes associated with geophysical fluids) is missing. This paper addresses the theoretical foundations supporting the implementation of such a physical reference surface in terms of an International Height Reference System and provides guidance for the coming activities required for the practical and sustainable realization of this system. Based on conceptual approaches of physical geodesy, the requirements for a unified global height reference system are derived. In accordance with the practice, its realization as the International Height Reference Frame is designed. Further steps for the implementation are also proposed.

75 FR 66083 - Iron Mask Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-27

... following: (1) A 225-foot- high, 1,795-foot-long upper dam made of either zoned earth and rockfill or concrete-face earth and rockfill; (2) a 50-foot-high, 950-foot-long earth-filled upper saddle dike A; (3) a 20-foot-high, 400-foot-long earth-filled upper saddle dike B; (4) a 40-foot-high, 6,559-foot-long...

Properties of Earth's temporarily-captured flybys

NASA Astrophysics Data System (ADS)

Fedorets, Grigori; Granvik, Mikael

2014-11-01

In addition to the Moon, a population of small temporarily-captured NEOs is predicted to orbit the Earth. The definition of a natural Earth satellite is that it is on an elliptic geocentric orbit within 0.03 au from the Earth. The population is further divided into temporarily-captured orbiters (TCOs, or minimoons, making at least one full revolution around the Earth in a coordinate system co-rotating with the Sun) and temporarily-captured flybys (TCFs) which fail to make a full revolution, but are temporarily on an elliptic orbit around the Earth. Only one minimoon has been discovered to date, but it is expected that next generation surveys will be able to detect these objects regularly.Granvik et al. (2012) performed an extensive analysis of the behaviour of these temporarily-captured objects. One of the main results was that at any given moment there is at least one 1-meter-diameter minimoon in orbit around the Earth. However, the results of Granvik et al. (2012) raised questions considering the NES population such as the bimodality of the capture duration distribution and a distinctive lack of test particles within Earth's Hill sphere, which requires investigating the statistical properties also of the TCF population.In this work we confirm the population characteristics for minimoons described by Granvik et al. (2012), and extend the analysis to TCFs. For the calculations we use a Bulirsch-Stoer integrator implemented in the OpenOrb software package (Granvik et al. 2009). We study, e.g., the capture statistics, residence-time distributions, and steady-state properties of TCFs. Our preliminary results indicate that TCFs may be suitable targets for asteroid-redirect missions. More detailed knowledge of the TCF population will also improve our understanding of the link between temporarily-captured objects and NEOs in general.References: Granvik et al. (2009) MPS 44(12), 1853-1861; Granvik et al. (2012) Icarus 218, 262-277.

Feasibility study of a single, elliptical heliocentric Earth-Mars trajectory

NASA Technical Reports Server (NTRS)

Blake, M.; Fulgham, K.; Westrup, S.

1989-01-01

The initial intent of this design project was to evaluate the existence and feasibility of a single elliptical heliocentric Earth/Mars trajectory. This trajectory was constrained to encounter Mars twice in its orbit, within a time interval of 15 to 180 Earth days between encounters. The single ellipse restriction was soon found to be prohibitive for reasons shown later. Therefore, the approach taken in the design of the round-trip mission to Mars was to construct single-leg trajectories which connected two planets on two prescribed dates. Three methods of trajectory design were developed. Method 1 is an eclectic approach and employs Gaussian Orbit Determination (Method 1A) and Lambert-Euler Preliminary Orbit Determination (Method 1B) in conjunction with each other. Method 2 is an additional version of Lambert's Solution to orbit determination, and both a coplanar and a noncoplanar solution were developed within Method 2. In each of these methods, the fundamental variables are two position vectors and the time between the position vectors. In all methods, the motion was considered Keplerian motion and the reference frame origin was located at the sun. Perturbative effects were not considered in Method 1. The feasibility study of round-trip Earth/Mars trajectories maintains generality by considering only heliocentric trajectory parameters and planetary approach conditions. The coordinates and velocity components of the planets, for the standard epoch J2000, were computed from an approximate set of osculating elements by the procedure outlined in an ephemeris of coordinates.

Preliminary Results from NASA/GSFC Ka-Band High Rate Demonstration for Near-Earth Communications

NASA Technical Reports Server (NTRS)

Wong, Yen; Gioannini, Bryan; Bundick, Steven N.; Miller, David T.

2004-01-01

In early 2000, the National Aeronautics and Space Administration (NASA) commenced the Ka-Band Transition Project (KaTP) as another step towards satisfying wideband communication requirements of the space research and earth exploration-satellite services. The KaTP team upgraded the ground segment portion of NASA's Space Network (SN) in order to enable high data rate space science and earth science services communications. The SN ground segment is located at the White Sands Complex (WSC) in New Mexico. NASA conducted the SN ground segment upgrades in conjunction with space segment upgrades implemented via the Tracking and Data Relay Satellite (TDRS)-HIJ project. The three new geostationary data relay satellites developed under the TDRS-HIJ project support the use of the inter-satellite service (ISS) allocation in the 25.25-27.5 GHz band (the 26 GHz band) to receive high speed data from low earth-orbiting customer spacecraft. The TDRS H spacecraft (designated TDRS-8) is currently operational at a 171 degrees west longitude. TDRS I and J spacecraft on-orbit testing has been completed. These spacecraft support 650 MHz-wide Ka-band telemetry links that are referred to as return links. The 650 MHz-wide Ka-band telemetry links have the capability to support data rates up to at least 1.2 Gbps. Therefore, the TDRS-HIJ spacecraft will significantly enhance the existing data rate elements of the NASA Space Network that operate at S-band and Ku-band.

NBL CRM 112-A: A new certified isotopic composition

NASA Astrophysics Data System (ADS)

Thomas, R. B.; Essex, R. M.; Mason, P.

2007-12-01

NBL CRM 112-A Uranium Metal Assay Standard is commonly used as a natural uranium isotopic reference material within the earth science mass spectrometry community. The metal is from the same parent material as NBS SRM 960, the uranyl nitrate solution, CRM 145, and the high-purity uranyl nitrate solution CRM 145-B. Because CRM 112-A has not yet been certified for isotopic composition, it has been assumed that this material has a natural 235U/238U (0.0072527), and the δ234U has been determined by measurement (e.g. -37.1‰; Cheng et al., 2000). These values have been widely used to calibrate the concentration of spikes and standards, and to correct measurements for instrument or mass bias. New, preliminary, isotopic measurements on CRM 145 and CRM 112-A performed at New Brunswick Laboratory suggest that these reference materials have a slightly lower 235U/238U and δ234U than have been commonly used. If this is the case, then data using the accepted values may be slightly biased. The significance of this bias will depend on the uncertainty of the measurement, how the CRM 112-A data is used to correct measurement data, the cited values that were used to correct the data, and the final certified values of the CRM. This fall, New Brunswick Laboratory is certifying the isotopic composition of the CRM 112-A metal using high precision thermal ionization mass spectrometry techniques. Upon completion of certification, the new CRM 112- A standard with certified isotopic ratios will provide the earth science community with a well characterized and traceable reference for calibrating and correcting their mass spectrometry measurement systems.

40 CFR 421.271 - Specialized definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth Metals.... (b) The term rare earth metals refers to the elements scandium, yttrium, and lanthanum to lutetium, inclusive. (c) The term mischmetal refers to a rare earth metal alloy comprised of the natural mixture of...

40 CFR 421.271 - Specialized definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth Metals.... (b) The term rare earth metals refers to the elements scandium, yttrium, and lanthanum to lutetium, inclusive. (c) The term mischmetal refers to a rare earth metal alloy comprised of the natural mixture of...

40 CFR 421.271 - Specialized definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth Metals.... (b) The term rare earth metals refers to the elements scandium, yttrium, and lanthanum to lutetium, inclusive. (c) The term mischmetal refers to a rare earth metal alloy comprised of the natural mixture of...

40 CFR 421.271 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth Metals.... (b) The term rare earth metals refers to the elements scandium, yttrium, and lanthanum to lutetium, inclusive. (c) The term mischmetal refers to a rare earth metal alloy comprised of the natural mixture of...

Collecting cometary soil samples? Development of the ROSETTA sample acquisition system

NASA Technical Reports Server (NTRS)

Coste, P. A.; Fenzi, M.; Eiden, Michael

1993-01-01

In the reference scenario of the ROSETTA CNRS mission, the Sample Acquisition System is mounted on the Comet Lander. Its tasks are to acquire three kinds of cometary samples and to transfer them to the Earth Return Capsule. Operations are to be performed in vacuum and microgravity, on a probably rough and dusty surface, in a largely unknown material, at temperatures in the order of 100 K. The concept and operation of the Sample Acquisition System are presented. The design of the prototype corer and surface sampling tool, and of the equipment for testing them at cryogenic temperatures in ambient conditions and in vacuum in various materials representing cometary soil, are described. Results of recent preliminary tests performed in low temperature thermal vacuum in a cometary analog ice-dust mixture are provided.

The Effect of Verbal and Visuo-Spatial Abilities on the Development of Knowledge of the Earth

NASA Astrophysics Data System (ADS)

Kikas, Eve

2006-09-01

Difficulties in students’ understanding of the spherical model of the Earth have been shown in previous studies. One of the reasons for these difficulties lies in beliefs and preliminary knowledge that hinder the interpretation of the scientific knowledge, the other reason may lie in the low level of verbal and visuo-spatial abilities. The study aims to investigate the effect of verbal and visuo-spatial abilities, but also that of preliminary knowledge on the later development of the knowledge of the Earth in school. 176 schoolchildren (96 boys and 80 girls) from five schools were tested; the mean age of the children during the first interview was seven years and eight months. All students were interviewed twice in grades 1 and 2, before and after they had learnt the topic in school. Factual, scientific and synthetic knowledge was assessed. The facilitative effect of visuo-spatial and verbal abilities and preliminary factual and scientific knowledge on students’ knowledge of astronomy after having learnt the topic in school was shown. In contrast, the hindering effect of synthetic knowledge was not found.

An assessment of the near-surface accuracy of the international geomagnetic reference field 1980 model of the main geomagnetic field

USGS Publications Warehouse

Peddie, N.W.; Zunde, A.K.

1985-01-01

The new International Geomagnetic Reference Field (IGRF) model of the main geomagnetic field for 1980 is based heavily on measurements from the MAGSAT satellite survey. Assessment of the accuracy of the new model, as a description of the main field near the Earth's surface, is important because the accuracy of models derived from satellite data can be adversely affected by the magnetic field of electric currents in the ionosphere and the auroral zones. Until now, statements about its accuracy have been based on the 6 published assessments of the 2 proposed models from which it was derived. However, those assessments were either regional in scope or were based mainly on preliminary or extrapolated data. Here we assess the near-surface accuracy of the new model by comparing it with values for 1980 derived from annual means from 69 magnetic observatories, and by comparing it with WC80, a model derived from near-surface data. The comparison with observatory-derived data shows that the new model describes the field at the 69 observatories about as accurately as would a model derived solely from near-surface data. The comparison with WC80 shows that the 2 models agree closely in their description of D and I near the surface. These comparisons support the proposition that the new IGRF 1980 main-field model is a generally accurate description of the main field near the Earth's surface in 1980. ?? 1985.

VLBI-based Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You terrestrial reference frames and to predict the variable orientation of the Earth in three-dimensional space antennas that define a VLBI-based Terrestrial Reference Frame (TRF) and the Earth Orientation Parameters

Ginger

NASA Astrophysics Data System (ADS)

di Virgilio, Angela D. V.

Gyroscopes IN General Relativity (GINGER) is a proposal of an Earth-base experiment to measure the Lense-Thirring effect. GINGER uses an array of ring lasers, which are the most sensitive inertial sensors to measure the rotation rate of the Earth. GINGER is based on a three-dimensional array of large size ring lasers, able to measure the de Sitter and Lense-Thirring effects. The instrument will be located in the INFN Gran Sasso underground laboratory, in Italy. We describe preliminary developments and measurements. Earlier prototypes based in Italy, GP2, GINGERino, and G-LAS are also described and their preliminary results reported.

Preliminary analysis of coronal electron content measurements from spacecraft Helios A around first solar occultation

NASA Technical Reports Server (NTRS)

Edenhofer, P.; Esposito, P. B.; Martin, W. L.; Zygielbaum, A. I.; Hansen, R. T.; Hansen, S. F.; Lueneburg, E.

1977-01-01

Steady-state and dynamical features of the electron density distribution in the solar corona emerge from a preliminary analysis of Helios A electron content measurements. There are strong indications that correlations can be established with earth-bound K-coronagraph measurements.

Satellite-tracking and Earth dynamics research programs

NASA Technical Reports Server (NTRS)

1981-01-01

The major focus for operations during this period was the preliminary MERIT Campaign and its intensive tracking of LAGEOS for polar motion and Earth rotation studies. The data acquired from LAGEOS were used for other geophysical investigations, including studies of crustal dynamics, and Earth and ocean tides, and for the general development of precision orbit determination. The network performed regular tracking of several other retroreflector satellites including GEOS-1, GEOS-3, BE-C, and Starlette for refined determinations of station coordinates and Earth's gravity field and for studies of solid Earth dynamics.

76 FR 25320 - Indian Blanket Water LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-04

...: (1) A 120-foot-high, 3,200-foot-long earth embankment dam; (2) a 30- foot-high, 300-foot-long earth...-foot storage capacity; (4) a 60-foot-high, 5,600-foot-long earth embankment dam creating; (5) a lower... characters, without prior registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment...

Earth Sciences Requirements for the Information Sciences Experiment System

NASA Technical Reports Server (NTRS)

Bowker, David E. (Editor); Katzberg, Steve J. (Editor); Wilson, R. Gale (Editor)

1990-01-01

The purpose of the workshop was to further explore and define the earth sciences requirements for the Information Sciences Experiment System (ISES), a proposed onboard data processor with real-time communications capability intended to support the Earth Observing System (Eos). A review of representative Eos instrument types is given and a preliminary set of real-time data needs has been established. An executive summary is included.

Radar Observation of Large Attenuation in Convective Storms: Implications for the Dropsize Distribution

NASA Technical Reports Server (NTRS)

Tian, Lin; Heymsfield, G. M.; Srivastava, R. C.

2000-01-01

Airborne meteorological radars typically operate at attenuating wavelengths. The path integrated attenuation (PIA) can be estimated using the surface reference technique (SRT). In this method, an initial value is determined for the radar cross section of the earth surface in a rain-free area in relatively close proximity to the rain cloud. During subsequent observations of precipitation any decrease 'in the observed surface cross section from the reference value s assumed to be a result of the two-way attenuation along the propagation path. In this paper we present selected instances of high PIA observed over land by an airborne radar. The observations were taken in Brazil and Florida during TRMM (Tropical Rainfall Measurement Mission) field campaigns. We compared these observations with collocated and nearly simultaneous ground-based radar observations by an S-band radar that is not subject to significant attenuation. In this preliminary evaluation, a systematic difference in the attenuation in the two storms is attributed to a difference in the raindrop size distributions; this is supported by observations of ZDR (differential reflectivity).

MW-Class Electric Propulsion System Designs for Mars Cargo Transport

NASA Technical Reports Server (NTRS)

Gilland, James H.; LaPointe, Michael R.; Oleson, Steven; Mercer, Carolyn; Pencil, Eric; Maosn, Lee

2011-01-01

Multi-kilowatt electric propulsion systems are well developed and have been used on commercial and military satellites in Earth orbit for several years. Ion and Hall thrusters have also propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system. High power electric propulsion systems are currently being considered to support piloted missions to near earth asteroids, as cargo transport for sustained lunar or Mars exploration, and for very high-power piloted missions to Mars and the outer planets. Using NASA Mars Design Architecture 5.0 as a reference, a preliminary parametric analysis was performed to determine the suitability of a nuclear powered, MW-class electric propulsion system for Mars cargo transport. For this initial analysis, high power 100-kW Hall thrusters and 250-kW VASIMR engines were separately evaluated to determine optimum vehicle architecture and estimated performance. The DRA 5.0 cargo mission closed for both propulsion options, delivering a 100 t payload to Mars orbit and reducing the number of heavy lift launch vehicles from five in the baseline DRA 5.0 architecture to two using electric propulsion. Under an imposed single engine-out mission success criteria, the VASIMR system took longer to reach Mars than did the Hall system, arising from the need to operate the VASIMR thrusters in pairs during the spiral out from low Earth orbit.

Free Global Dsm Assessment on Large Scale Areas Exploiting the Potentialities of the Innovative Google Earth Engine Platform

NASA Astrophysics Data System (ADS)

Nascetti, A.; Di Rita, M.; Ravanelli, R.; Amicuzi, M.; Esposito, S.; Crespi, M.

2017-05-01

The high-performance cloud-computing platform Google Earth Engine has been developed for global-scale analysis based on the Earth observation data. In particular, in this work, the geometric accuracy of the two most used nearly-global free DSMs (SRTM and ASTER) has been evaluated on the territories of four American States (Colorado, Michigan, Nevada, Utah) and one Italian Region (Trentino Alto- Adige, Northern Italy) exploiting the potentiality of this platform. These are large areas characterized by different terrain morphology, land covers and slopes. The assessment has been performed using two different reference DSMs: the USGS National Elevation Dataset (NED) and a LiDAR acquisition. The DSMs accuracy has been evaluated through computation of standard statistic parameters, both at global scale (considering the whole State/Region) and in function of the terrain morphology using several slope classes. The geometric accuracy in terms of Standard deviation and NMAD, for SRTM range from 2-3 meters in the first slope class to about 45 meters in the last one, whereas for ASTER, the values range from 5-6 to 30 meters. In general, the performed analysis shows a better accuracy for the SRTM in the flat areas whereas the ASTER GDEM is more reliable in the steep areas, where the slopes increase. These preliminary results highlight the GEE potentialities to perform DSM assessment on a global scale.

47 CFR 25.109 - Cross-reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

... General § 25.109 Cross-reference. (a) Space and earth stations in the Amateur Satellite Service are licensed under 47 CFR part 97. (b) Ship earth stations in the Maritime Mobile-Satellite Service transmitting in the 1626.5-1646.5 MHz band are subject to licensing under 47 CFR part 80. (c) Earth stations in...

47 CFR 25.109 - Cross-reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... General § 25.109 Cross-reference. (a) Space and earth stations in the Amateur Satellite Service are licensed under 47 CFR part 97. (b) Ship earth stations in the Maritime Mobile-Satellite Service transmitting in the 1626.5-1646.5 MHz band are subject to licensing under 47 CFR part 80. (c) Earth stations in...

Preparations for the IGS realization of ITRF2014

NASA Astrophysics Data System (ADS)

Rebischung, Paul; Schmid, Ralf

2016-04-01

The International GNSS Service (IGS) currently prepares its own realization, called IGS14, of the latest release of the International Terrestrial Reference Frame (ITRF2014). This preparation involves: - a selection of the most suitable reference frame (RF) stations from the complete set of GNSS stations in ITRF2014; - the design of a well-distributed core network of RF stations for the purpose of aligning global GNSS solutions; - a re-evaluation of the GPS and GLONASS satellite antenna phase center offsets (PCOs), based on the SINEX files provided by the IGS Analysis Centers (ACs) in the frame of the second IGS reprocessing campaign repro2. This presentation will first cover the criteria used for the selection of the IGS14 and IGS14 core RF stations as well as preliminary station selection results. We will then use the preliminary IGS14 RF to re-align the daily IGS combined repro2 SINEX solutions and study the impact of the RF change on GNSS-derived geodetic parameter time series. In a second part, we will focus on the re-evaluation of the GNSS satellite antenna PCOs. A re-evaluation of at least their radial (z) components is indeed required, despite the negligible scale difference between ITRF2008 and ITRF2014, because of modeling changes recently introduced within the IGS which affect the scale of GNSS terrestrial frames (Earth radiation pressure, antenna thrust). Moreover, the 13 GPS and GLONASS satellites launched since September 2012 are currently assigned preliminary block-specific mean PCO values which need to be updated. From the daily AC repro2 SINEX files, we will therefore derive time series of satellite z-PCO estimates and analyze the resulting time series. Since several ACs provided all three components of the satellite PCOs in their SINEX files, we will additionally derive similar x- and y-PCO time series and discuss the relevance of their potential re-evaluation.

Reference Data Layers for Earth and Environmental Science: History, Frameworks, Science Needs, Approaches, and New Technologies

NASA Astrophysics Data System (ADS)

Lenhardt, W. C.

2015-12-01

Global Mapping Project, Web-enabled Landsat Data (WELD), International Satellite Land Surface Climatology Project (ISLSCP), hydrology, solid earth dynamics, sedimentary geology, climate modeling, integrated assessments and so on all have needs for or have worked to develop consistently integrated data layers for Earth and environmental science. This paper will present an overview of an abstract notion of data layers of this types, what we are referring to as reference data layers for Earth and environmental science, highlight some historical examples, and delve into new approaches. The concept of reference data layers in this context combines data availability, cyberinfrastructure and data science, as well as domain science drivers. We argue that current advances in cyberinfrastructure such as iPython notebooks and integrated science processing environments such as iPlant's Discovery Environment coupled with vast arrays of new data sources warrant another look at the how to create, maintain, and provide reference data layers. The goal is to provide a context for understanding science needs for reference data layers to conduct their research. In addition, to the topics described above this presentation will also outline some of the challenges to and present some ideas for new approaches to addressing these needs. Promoting the idea of reference data layers is relevant to a number of existing related activities such as EarthCube, RDA, ESIP, the nascent NSF Regional Big Data Innovation Hubs and others.

Benchmarking Reference Desk Service in Academic Health Science Libraries: A Preliminary Survey.

ERIC Educational Resources Information Center

Robbins, Kathryn; Daniels, Kathleen

2001-01-01

This preliminary study was designed to benchmark patron perceptions of reference desk services at academic health science libraries, using a standard questionnaire. Responses were compared to determine the library that provided the highest-quality service overall and along five service dimensions. All libraries were rated very favorably, but none…

76 FR 60016 - Bellwood Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-28

...-high rock or earth fill main dam and a new 2,500-foot-long, 60-foot-high rock or earth fill saddle dam...-long, 185-foot-high rock or earth fill dam forming a lower reservoir having a surface area of 120 acres... registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your...

Rare earth element mineralogy, geochemistry, and preliminary resource assessment of the Khanneshin carbonatite complex, Helmand Province, Afghanistan

USGS Publications Warehouse

Tucker, Robert D.; Belkin, Harvey E.; Schulz, Klaus J.; Peters, Stephen G.; Buttleman, Kim P.

2011-01-01

There is increased concern about the future availability of rare earth elements (REE) because of China's dominance as the supplier of more than 95 percent of world REE output, their decision to restrict exports of rare earth products, and the rapid increase in world-wide consumption of rare earth product. As a result, countries such as the United States, Japan, and member nations of the European Union face a future of tight supplies and high prices for rare earth products unless other sources of REE are found and developed (Long and others, 2010; U.S. Geological Survey, 2011, p. 128-129, 184-185). We report and describe a significant new deposit of light rare earth elements (LREE), estimated at 1 Mt, within the Khanneshin carbonatite complex of south Afghanistan. The potential resource is located in a remote and rugged part of the igneous complex in a region previously identified by Soviet geologists in the 1970s. This report reviews the geologic setting of LREE deposit, presents new geochemical data documenting the grade of LREE mineralization, briefly describes the mineralogy and mineralogical associations of the deposit, and presents a preliminary estimate of LREE resources based on our current understanding of the geology.

Preliminary Design of the Brazilian's National Institute for Space Research Broadband Radiometer for Solar Observations

NASA Astrophysics Data System (ADS)

Berni, L. A.; Vieira, L. E. A.; Savonov, G. S.; Dal Lago, A.; Mendes, O.; Silva, M. R.; Guarnieri, F.; Sampaio, M.; Barbosa, M. J.; Vilas Boas, J. V.; Branco, R. H. F.; Nishimori, M.; Silva, L. A.; Carlesso, F.; Rodríguez Gómez, J. M.; Alves, L. R.; Vaz Castilho, B.; Santos, J.; Silva Paula, A.; Cardoso, F.

2017-10-01

The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).

ORCA: measuring the neutrino mass hierarchy with atmospheric neutrinos in the Mediterranean

NASA Astrophysics Data System (ADS)

Van Elewyck, Véronique; KM3NeT Collaboration

2015-04-01

Since the measurement of the mixing angle θ13, the determination of the neutrino mass hierarchy has become a central challenge of neutrino physics. Recent studies have pointed out that it could reveal itself in the atmospheric neutrino sector, where oscillations are affected by Earth matter effects. This contribution reports on the ORCA feasibility study for such a measurement with an underwater Cherenkov detector based on the technology developed for the KM3NeT neutrino telescope. The baseline performances are discussed for a reference detector with 50 instrumented lines. Preliminary projections, based on the muon channel only, indicate that a 3 — 5σ significance measurement is within reach of a detector with an exposure of the order of 20 Mton years. Further improvement is expected to come from the electron channel, which is currently under study.

Decadal GPS Time Series and Velocity Fields Spanning the North American Continent and Beyond: New Data Products, Cyberinfrastructure and Case Studies from the EarthScope Plate Boundary Observatory (PBO) and Other Regional Networks

NASA Astrophysics Data System (ADS)

Phillips, D. A.; Herring, T.; Melbourne, T. I.; Murray, M. H.; Szeliga, W. M.; Floyd, M.; Puskas, C. M.; King, R. W.; Boler, F. M.; Meertens, C. M.; Mattioli, G. S.

2017-12-01

The Geodesy Advancing Geosciences and EarthScope (GAGE) Facility, operated by UNAVCO, provides a diverse suite of geodetic data, derived products and cyberinfrastructure services to support community Earth science research and education. GPS data and products including decadal station position time series and velocities are provided for 2000+ continuous GPS stations from the Plate Boundary Observatory (PBO) and other networks distributed throughout the high Arctic, North America, and Caribbean regions. The position time series contain a multitude of signals in addition to the secular motions, including coseismic and postseismic displacements, interseismic strain accumulation, and transient signals associated with hydrologic and other processes. We present our latest velocity field solutions, new time series offset estimate products, and new time series examples associated with various phenomena. Position time series, and the signals they contain, are inherently dependent upon analysis parameters such as network scaling and reference frame realization. The estimation of scale changes for example, a common practice, has large impacts on vertical motion estimates. GAGE/PBO velocities and time series are currently provided in IGS (IGb08) and North America (NAM08, IGb08 rotated to a fixed North America Plate) reference frames. We are reprocessing all data (1996 to present) as part of the transition from IGb08 to IGS14 that began in 2017. New NAM14 and IGS14 data products are discussed. GAGE/PBO GPS data products are currently generated using onsite computing clusters. As part of an NSF funded EarthCube Building Blocks project called "Deploying MultiFacility Cyberinfrastructure in Commercial and Private Cloud-based Systems (GeoSciCloud)", we are investigating performance, cost, and efficiency differences between local computing resources and cloud based resources. Test environments include a commercial cloud provider (Amazon/AWS), NSF cloud-like infrastructures within XSEDE (TACC, the Texas Advanced Computing Center), and in-house cyberinfrastructures. Preliminary findings from this effort are presented. Web services developed by UNAVCO to facilitate the discovery, customization and dissemination of GPS data and products are also presented.

Thermoelasticity of (Mg,Fe)SiO3 perovskite

NASA Astrophysics Data System (ADS)

Shukla, Gaurav; Wu, Zhongqing; Hsu, Han; Cococcioni, Matteo; Wentzcovitch, Renata

2015-03-01

We present LDA+U calculations of high temperature elastic properties of (Mg(1 - x)Fex2+)SiO3 bridgemanite (0 <= x <= 0 . 125), the most abundant constituent of Earth's lower mantle. Calculations of aggregate elastic moduli and acoustic velocities for the Mg-end member (x=0) are in excellent agreement with the latest high pressure and high temperature experimental measurements. In the iron bearing system, we particularly focus on the change in thermoelastic parameters across the state change that occurs in ferrous iron above ~30 GPa, often attributed to a high-spin (HS) to intermediate spin (IS) crossover but explained by calculations as a lateral displacement of substitutional iron in the perovskite cage. We show that the measured effect on the equation of state of this change in the state of iron can be explained by the lateral displacement of substitutional iron, not by the HS to IS crossover. Calculated elastic properties of (Mg0.875 Fe0.125 2 +)SiO3 along an adiabatic mantle geotherm, somewhat overestimate longitudinal velocities but produce densities and shear velocities consistent with Preliminary Reference Earth Model data throughout most of the lower mantle. Research supported by NSF/EAR and NSF/CAREER.

Velocity and Density Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion Simulations

USGS Publications Warehouse

Stephenson, William J.

2007-01-01

In support of earthquake hazards and ground motion studies in the Pacific Northwest, three-dimensional P- and S-wave velocity (3D Vp and Vs) and density (3D rho) models incorporating the Cascadia subduction zone have been developed for the region encompassed from about 40.2°N to 50°N latitude, and from about -122°W to -129°W longitude. The model volume includes elevations from 0 km to 60 km (elevation is opposite of depth in model coordinates). Stephenson and Frankel (2003) presented preliminary ground motion simulations valid up to 0.1 Hz using an earlier version of these models. The version of the model volume described here includes more structural and geophysical detail, particularly in the Puget Lowland as required for scenario earthquake simulations in the development of the Seattle Urban Hazards Maps (Frankel and others, 2007). Olsen and others (in press) used the model volume discussed here to perform a Cascadia simulation up to 0.5 Hz using a Sumatra-Andaman Islands rupture history. As research from the EarthScope Program (http://www.earthscope.org) is published, a wealth of important detail can be added to these model volumes, particularly to depths of the upper-mantle. However, at the time of development for this model version, no EarthScope-specific results were incorporated. This report is intended to be a reference for colleagues and associates who have used or are planning to use this preliminary model in their research. To this end, it is intended that these models will be considered a beginning template for a community velocity model of the Cascadia region as more data and results become available.

TEMPEST Level-0 Theory

DTIC Science & Technology

2011-11-01

trajectory of the ship-fixed reference system relative to an earth-fixed reference system. The earth-fixed reference frame, EEE ZYX O , is assumed to be...the ship and moves with all the motions of the ship. The EEE ZYX O axis system is fixed to the earth. A third axis system, ’’’ zyxO , is required...added to account for the turbulence in the propeller slipstream: 2075.0445.0225.1 eeS aa  radians for aeɛ.0 565.0S radians for ae

Measured Fluid Flow in an Active H2O-CO2 Geothermal Well as an Analog to Fluid Flow in Fractures on Mars: Preliminary Report

NASA Technical Reports Server (NTRS)

Kieffer, Susan W.; Brown, K. L.; Simmons, Stuart F.; Watson, Arnold

2004-01-01

Water in the Earth's crust generally contains dissolved gases such as CO2. Models for both 'Blue Mars' (H2O-driven processes) and 'White Mars' (CO2-driven processes) predict liquid H2O with dissolved CO2 at depth. The fate of dissolved CO2 as this mixture rises toward the surface has not been quantitatively explored. Our approach is a variation on NASA's 'Follow the Water' as we 'Follow the Fluid' from depth to the surface in hydrothermal areas on Earth and extrapolate our results to Mars. This is a preliminary report on a field study of fluid flow in a producing geothermal well. For proprietary reasons, the name and location of this well cannot be revealed, so we have named it 'Earth1' for this study.

Reference Frames in Earth Rotation Theories

NASA Astrophysics Data System (ADS)

Ferrándiz, José M.; Belda, Santiago; Heinkelmann, Robert; Getino, Juan; Schuh, Harald; Escapa, Alberto

2015-04-01

Nowadays the determination of the Earth Orientation Parameters (EOP) and the different Terrestrial Reference Frames (TRF) are not independent. The available theories of Earth rotation aims at providing the orientation of a certain reference system linked somehow to the Earth with respect to a given celestial system, considered as inertial. In the past years a considerable effort has been dedicated to the improvement of the TRF realizations, following the lines set up in the 1980's. However, the reference systems used in the derivation of the theories have been rather considered as something fully established, not deserving a special attention. In this contribution we review the definitions of the frames used in the main theoretical approaches, focusing on those used in the construction of IAU2000, and the extent to which their underlying hypotheses hold. The results are useful to determine the level of consistency of the predicted and determined EOP.

The Kjeldahl method as a primary reference procedure for total protein in certified reference materials used in clinical chemistry. II. Selection of direct Kjeldahl analysis and its preliminary performance parameters.

PubMed

Vinklárková, Bára; Chromý, Vratislav; Šprongl, Luděk; Bittová, Miroslava; Rikanová, Milena; Ohnútková, Ivana; Žaludová, Lenka

2015-01-01

To select a Kjeldahl procedure suitable for the determination of total protein in reference materials used in laboratory medicine, we reviewed in our previous article Kjeldahl methods adopted by clinical chemistry and found an indirect two-step analysis by total Kjeldahl nitrogen corrected for its nonprotein nitrogen and a direct analysis made on isolated protein precipitates. In this article, we compare both procedures on various reference materials. An indirect Kjeldahl method gave falsely lower results than a direct analysis. Preliminary performance parameters qualify the direct Kjeldahl analysis as a suitable primary reference procedure for the certification of total protein in reference laboratories.

ESSG-based global spatial reference frame for datasets interrelation

NASA Astrophysics Data System (ADS)

Yu, J. Q.; Wu, L. X.; Jia, Y. J.

2013-10-01

To know well about the highly complex earth system, a large volume of, as well as a large variety of, datasets on the planet Earth are being obtained, distributed, and shared worldwide everyday. However, seldom of existing systems concentrates on the distribution and interrelation of different datasets in a common Global Spatial Reference Frame (GSRF), which holds an invisble obstacle to the data sharing and scientific collaboration. Group on Earth Obeservation (GEO) has recently established a new GSRF, named Earth System Spatial Grid (ESSG), for global datasets distribution, sharing and interrelation in its 2012-2015 WORKING PLAN.The ESSG may bridge the gap among different spatial datasets and hence overcome the obstacles. This paper is to present the implementation of the ESSG-based GSRF. A reference spheroid, a grid subdvision scheme, and a suitable encoding system are required to implement it. The radius of ESSG reference spheroid was set to the double of approximated Earth radius to make datasets from different areas of earth system science being covered. The same paramerters of positioning and orienting as Earth Centred Earth Fixed (ECEF) was adopted for the ESSG reference spheroid to make any other GSRFs being freely transformed into the ESSG-based GSRF. Spheroid degenerated octree grid with radius refiment (SDOG-R) and its encoding method were taken as the grid subdvision and encoding scheme for its good performance in many aspects. A triple (C, T, A) model is introduced to represent and link different datasets based on the ESSG-based GSRF. Finally, the methods of coordinate transformation between the ESSGbased GSRF and other GSRFs were presented to make ESSG-based GSRF operable and propagable.

Greenland GPS network: Measurements and Models of 3D Elastic deformation

NASA Astrophysics Data System (ADS)

Khan, S. A.; van Dam, T. M.; Bevis, M. G.; Sasgen, I.; Bamber, J. L.; Helm, V.; Bjork, A. A.; Liu, L.; Kjaer, K. H.; Knudsen, P.; Kjeldsen, K. K.

2017-12-01

The Greenland GPS Network (GNET) uses the Global Positioning System (GPS) to measure the displacement of bedrock exposed near the margins of the Greenland ice sheet. The entire network is uplifting in response to past and present-day changes in ice mass. Here, we focus on present-day changes and compare measurements with models. To retrieve 3D elastic displacements from GPS time series, we correct our observations for glacial-isostatic adjustment and tectonic plate motion, and study the effect of the underlying mantle viscosity, ice load history and Euler parameters. To model 3D elastic displacements, we first estimate mass loss using 1995-2014 NASA's Airborne Topographic Mapper (ATM) flights derived altimetry, supplemented with laser altimetry observations from the Ice, Cloud, and Land Elevation Satellite (ICESat) during 2003-2009; the airborne Land, Vegetation, and Ice Sensor (LVIS) instrument during 2007-2013; radar altimetry from the CryoSat-2 satellite during 2010-2017; and European Remote-Sensing Satellite-1 (ERS-1) and ERS-2 data during 1995-2003. We converted the volume loss rate into a mass loss rate accounting for firn compaction as described by Kuipers Munneke et al. (2015). We predict the elastic displacements by convolving mass loss estimates with Green's functions for vertical and horizontal displacements. We use a variety of elastic Green's functions and mass change grid resolutions, respectively, to study the sensitivity of 3D elastic deformation on Earth model parameters different from the Preliminary Reference Earth Reference Model (PREM; Dziewonski & Anderson 1981) and the forcing ice load.

Air-Cored Linear Induction Motor for Earth-to-Orbit Systems

NASA Technical Reports Server (NTRS)

Zabar, Zivan; Levi, Enrico; Birenbaum, Leo

1996-01-01

The need for lowering the cost of Earth-to-Orbit (ETO) launches has prompted consideration of electromagnetic launchers. A preliminary design based on the experience gained in an advanced type of coilgun and on innovative ideas shows that such a launcher is technically feasible with almost off-the-shelf components.

Preliminary study on using rare earth elements to trace non-point source phosphorous loss

USDA-ARS?s Scientific Manuscript database

The environmental fate of phosphorus (P) is of concern as P is a primary cause of freshwater eutrophication. Rare earth elements (REEs) have been successfully used in the analysis of soil erosion and pollutant sources, as well as in the analysis of mineral genesis. To better understand the potential...

Study of extraterrestrial disposal of radioactive wastes. Part 2: Preliminary feasibility screening study of extraterrestrial disposal of radioactive wastes in concentrations, matrix materials, and containers designed for storage on earth

NASA Technical Reports Server (NTRS)

Hyland, R. E.; Wohl, M. L.; Thompson, R. L.; Finnegan, P. M.

1972-01-01

The results are reported of a preliminary feasibility screening study for providing long-term solutions to the problems of handling and managing radioactive wastes by extraterrestrial transportation of the wastes. Matrix materials and containers are discussed along with payloads, costs, and destinations for candidate space vehicles. The conclusions reached are: (1) Matrix material such as spray melt can be used without exceeding temperature limits of the matrix. (2) The cost in mills per kw hr electric, of space disposal of fission products is 4, 5, and 28 mills per kw hr for earth escape, solar orbit, and solar escape, respectively. (3) A major factor effecting cost is the earth storage time. Based on a normal operating condition design for solar escape, a storage time of more than sixty years is required to make the space disposal charge less than 10% of the bus-bar electric cost. (4) Based on a 10 year earth storage without further processing, the number of shuttle launches required would exceed one per day.

Expected Improvements in VLBI Measurements of the Earth's Orientation

NASA Technical Reports Server (NTRS)

Ma, Chopo

2003-01-01

Measurements of the Earth s orientation since the 1970s using space geodetic techniques have provided a continually expanding and improving data set for studies of the Earth s structure and the distribution of mass and angular momentum. The accuracy of current one-day measurements is better than 100 microarcsec for the motion of the pole with respect to the celestial and terrestrial reference frames and better than 3 microsec for the rotation around the pole. VLBI uniquely provides the three Earth orientation parameters (nutation and UTI) that relate the Earth to the extragalactic celestial reference frame. The accuracy and resolution of the VLBI Earth orientation time series can be expected to improve substantially in the near future because of refinements in the realization of the celestial reference frame, improved modeling of the troposphere and non-linear station motions, larger observing networks, optimized scheduling, deployment of disk-based Mark V recorders, full use of Mark IV capabilities, and e-VLBI. More radical future technical developments will be discussed.

The Determination of Earth Orientation by VLBI and GNSS: Principles and Results

NASA Astrophysics Data System (ADS)

Capitaine, Nicole

2017-10-01

The Earth Orientation Parameters (EOP) connect the International Terrestrial Reference System (ITRS) to the Geocentric Celestial Reference System (GCRS). These parameters, i.e., Universal Time, UT1, and pole coordinates in the ITRS and in the GCRS, describe the irregularities of the Earth's rotation. They are mainly determined by two modern astro-geodetic techniques, VLBI (Very Long Baseline Radio Interferometry) on extragalactic radio sources, which is used to realize and maintain the International Celestial Reference System (ICRS), and Global Navigation Satellite System (GNSS), especially GPS (Global Positioning System), which has an important contribution to the realization of the ITRS. The aim of this presentation is twofold: to present the modern bases for the consider- ation of Earth orientation and to discuss how the principles of VLBI and GPS give access to the measure of different components of the EOP variations, especially UT1. The accuracy that can be achieved is based on the improved concepts, definitions, and models that have been adopted by IAU/IUGG resolutions on reference systems and Earth's rotation, as well as on the refined strategy of the observations.

Aviation's role in earth resources surveys

NASA Technical Reports Server (NTRS)

Syvertson, C. A.; Mulholland, D. R.

1972-01-01

The role of satellites designed to make a wide variety of earth observations is discussed along with the renewed interest in the use of aircraft as platforms for similar and complementary earth resources surveys. Surveys covering the areas of forestry, agriculture, hydrology, oceanography, geology, and geography are included. Aerials surveys equipped for nonphotographic remote sensing and aircraft flights synchronized with satellite observations to provide correlated data are discussed. Photographs are shown to illustrate preliminary results from several of the test sites.

Semi-analytical integration of the Earth's precession-nutation based on the GCRS coordinates of the CIP unit vector

NASA Astrophysics Data System (ADS)

Capitaine, N.; Folgueira, M.

2012-12-01

In a previous paper (Capitaine et al. 2006), referred here as Paper I, we demonstrated the possibility of integrating the Earth's rotational motion in terms of the coordinates (X, Y ) of the celestial intermediate pole (CIP) unit vector in the Geocentric celestial reference system (GCRS). Here, we report on the approach that has been followed for solving the equations in the case of an axially symmetric rigid Earth and the semi-analytical (X, Y ) solution obtained from the expression of the external torque acting on the Earth derived from the most complete semi-analytical solutions for the Earth, Moon and planets.

Earth Global Reference Atmospheric Model (GRAM) Overview and Updates: DOLWG Meeting

NASA Technical Reports Server (NTRS)

White, Patrick

2017-01-01

What is Earth-GRAM (Global Reference Atmospheric Model): Provides monthly mean and standard deviation for any point in atmosphere - Monthly, Geographic, and Altitude Variation; Earth-GRAM is a C++ software package - Currently distributed as Earth-GRAM 2016; Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents; Used by engineering community because of ability to create dispersions in atmosphere at a rapid runtime - Often embedded in trajectory simulation software; Not a forecast model; Does not readily capture localized atmospheric effects.

Learning to Explain Astronomy Across Moving Frames of Reference: Exploring the role of classroom and planetarium-based instructional contexts

NASA Astrophysics Data System (ADS)

Plummer, Julia Diane; Kocareli, Alicia; Slagle, Cynthia

2014-05-01

Learning astronomy involves significant spatial reasoning, such as learning to describe Earth-based phenomena and understanding space-based explanations for those phenomena as well as using the relevant size and scale information to interpret these frames of reference. This study examines daily celestial motion (DCM) as one case of how children learn to move between frames of reference in astronomy wherein one explains Earth-based descriptions of the Sun's, Moon's, and stars' apparent motion using the Earth's daily rotation. We analysed interviews with 8-9-year-old students (N = 99) who participated in one of four instructional conditions emphasizing: the space-based perspective; the Earth-based perspective in the planetarium; constructing explanations for the Earth-based observations; and a combination of the planetarium plus constructing explanations in the classroom. We used an embodied cognition framework to analyse outcomes while also considering challenges learners face due to the high cognitive demands of spatial reasoning. Results support the hypothesis that instruction should engage students in learning both the Earth-based observations and space-based explanations, as focusing on a single frame of reference resulted in less sophisticated explanations; however, few students were able to construct a fully scientific explanation after instruction.

Passive exposure of Earth radiation budget experiment components. LDEF experiment AO-147: Post-flight examinations and tests

NASA Technical Reports Server (NTRS)

Hickey, John R.

1992-01-01

The flight spare sensors of the Earth Radiation Budget (ERB) experiment of the Nimbus 6 and 7 missions were flown aboard the LDEF. The preliminary post retrieval examination and test results are presented here for the sensor windows and filters, the thermopile sensors and a cavity radiometer.

75 FR 61747 - Coffin Butte Energy Park, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-06

... Power Act (FPA), proposing to study the feasibility of the Coffin Butte Pumped Storage Water Power... triangular earth and roller compacted concrete embankment; creating a 50-acre upper reservoir with a storage...); (2) a 6,300-foot-long, 60-foot-high oval earth and roller compacted concrete embankment; creating a...

A Study of Students' Perceptions of the Organisation and Effectiveness of Fieldwork in Earth Sciences Education

ERIC Educational Resources Information Center

Marques, Luis; Praia, Joao; Kempa, Richard

2003-01-01

This paper reports the findings of a preliminary evaluation of an in-service training programme designed for practising geology/earth science teachers in Portuguese high schools and intended to enhance the effectiveness of fieldwork activities organised by them for their students. Among the points particularly stressed during the in-service…

Study of sensor spectral responses and data processing algorithms and architectures for onboard feature identification

NASA Technical Reports Server (NTRS)

Huck, F. O.; Davis, R. E.; Fales, C. L.; Aherron, R. M.

1982-01-01

A computational model of the deterministic and stochastic processes involved in remote sensing is used to study spectral feature identification techniques for real-time onboard processing of data acquired with advanced earth-resources sensors. Preliminary results indicate that: Narrow spectral responses are advantageous; signal normalization improves mean-square distance (MSD) classification accuracy but tends to degrade maximum-likelihood (MLH) classification accuracy; and MSD classification of normalized signals performs better than the computationally more complex MLH classification when imaging conditions change appreciably from those conditions during which reference data were acquired. The results also indicate that autonomous categorization of TM signals into vegetation, bare land, water, snow and clouds can be accomplished with adequate reliability for many applications over a reasonably wide range of imaging conditions. However, further analysis is required to develop computationally efficient boundary approximation algorithms for such categorization.

Deriving a Core Magnetic Field Model from Swarm Satellite Data

NASA Astrophysics Data System (ADS)

Lesur, V.; Rother, M.; Wardinski, I.

2014-12-01

A model of the Earth's core magnetic field has been built using Swarm satellite mission data and observatory quasi-definitive data. The satellite data processing scheme, which was used to derive previous satellite field models (i.e. GRIMM series), has been modified to handle discrepancies between the satellite total intensity data derived from the vector fluxgate magnetometer and the absolute scalar instrument. Further, the Euler angles, i.e. the angles between the vector magnetometer and the satellite reference frame, have been recalculated on a series of 30-day windows to obtain an accurate model of the core field for 2014. Preliminary derivations of core magnetic field and SV models for 2014 present the same characteristics as during the CHAMP era. The acceleration (i.e. the field second time derivative) has shown a rapid evolution over the last few years, and is present in the current model, which confirms previous observations.

Deep water tsunami simulation at global scale using an elastoacoustic approach

NASA Astrophysics Data System (ADS)

Salazar Monroy, E. F.; Ramirez-Guzman, L.; Bielak, J.; Sanchez-Sesma, F. J.

2017-12-01

In this work, we present the results for the first stage of a tsunami global simulation project using an elastoacoustic approach. The solid-fluid interaction, which is only valid on a global scale and far distances from the coast, is modelled using a finite element scheme for a 2D geometry. Comparing analytic and numerical solutions, we observe a good fit for a homogeneous domain - with an extension of 20 km - using 15 points per wavelength. Subsequently, we performed 2D realizations taking a section from a global 3D model and projecting the Tohoku-Oki source obtained by the USGS. The 3D Global model uses the ETOPO1 and the Preliminary Reference Earth Model (Dziewonski and Anderson, 1981). We analysed 3 cross sections, defined using DART buoys as a reference for each section (i.e., initial and final profile point). Surface water elevation obtained with this coupling strategy is constrained at low frequencies (0.2 Hz). We expect that this coupling strategy could approximate the model to high frequencies and realistic scenarios considering other geometries (i.e., 3D) and a complete domain (i.e., surface and deep).

ISSA/TSS power preliminary design

NASA Technical Reports Server (NTRS)

Main, John A.

1996-01-01

A projected power shortfall during the initial utilization flights of the International Space Station Alpha (ISSA) has prompted an inquiry into the use of the Tethered Satellite System (TSS) to provide station power. The preliminary design of the combined ISSA/TSS system is currently underway in the Preliminary Design Office at the Marshall Space Flight Center. This document focuses on the justification for using a tether system on space station, the physical principles behind such a system, and how it might be operated to best utilize its capabilities. The basic components of a simple DC generator are a magnet of some type and a conductive wire. Moving the wire through the magnetic field causes forces to be applied to the electric charges in the conductor, and thus current is induced to flow. This simple concept is the idea behind generating power with space-borne tether systems. The function of the magnet is performed by the earth's magnetic field, and orbiting a conductive tether about the earth effectively moves the tether through the field.

Glacial Isostatic Adjustment with ICE-6G{_}C (VM5a) and Laterally Heterogeneous Mantle Viscosity

NASA Astrophysics Data System (ADS)

Li, Tanghua; Wu, Patrick; Steffen, Holger

2017-04-01

Recently, Peltier et al. (2015) introduced the ICE-6GC (VM5a) ice-earth model pair, which has successfully explained many observations of Glacial Isostatic Adjustment (GIA) simultaneously. However, their earth model used (VM5a) to infer the ice history (ICE-6G_C) is laterally homogeneous with viscosity profile varying in the radial direction only. Since surface geology and seismic tomography clearly indicates that the Earth's material properties also vary in the lateral direction, laterally heterogeneity must be included in GIA models. This can be achieved by using the Coupled-Laplace-Finite-Element method (Wu 2004) to model GIA in a spherical, self-gravitating, compressible viscoelastic Earth with linear rheology and lateral heterogeneity. In fact, Wu et al (2013) have used such model with GIA observations (e.g. global relative sea level data, GRACE data with recent hydrology contributions removed and GPS crustal uplift rates) to study the thermal contribution to lateral heterogeneity in the mantle. Their lateral viscosity perturbations are inferred from the seismic shear wave tomography model S20A (Ekstrom & Dziewonski 1998) by applying a scaling law, which includes both the effect of anharmonicity and anelasticity. The thermal contribution to seismic tomography, which is represented by the beta factor in the scaling relationship, is searched in the upper and lower mantle, for the best combination that gives the best fit between GIA predictions and observations. However, their study is based on ICE-4G only, and the new ice-earth model pair may give other best beta value combinations in the upper and lower mantle. Here, we follow the work of Wu et al (2013) but use the new ICE-6GC ice model instead. The higher resolution seismic tomography model by Bunge & Grand (2000) substitutes S20A. Earth model VM5a is used as the reference background viscosity model. The full viscosity model is obtained by superposing the background model with the lateral viscosity perturbations inferred from the seismic tomography model (Bunge & Grand 2000) logarithmically. The preliminary results of these and other background viscosity profiles will be presented. References: Bunge, H.-P. & Grand, S. P. (2000). Mesozoic plate-motion history below the northeast Pacific Ocean from seismic images of the subducted Farallon slab. Nature, 405(6784):337-340. Peltier, W., Argus, D., and Drummond, R. (2015). Space geodesy constrains ice age terminal deglaciation: The global ICE-6GC (VM5a) model. Journal of Geophysical Research: Solid Earth, 120(1): 450-487. Wu, P. (2004). Using commercial finite element packages for the study of earth deformations, sea levels and the state of stress. Geophysical Journal International, 158(2): 401-408. Wu, P., Wang, H.S. & Steffen, H. (2012). The role of thermal effect on mantle seismic anomalies under Laurentia and Fennoscandia from observations of Glacial Isostatic Adjustment. Geophysical Journal International, 192(1):7-17.

SRM-Assisted Trajectory for the GTX Reference Vehicle

NASA Technical Reports Server (NTRS)

Riehl, John; Trefny, Charles; Kosareo, Daniel

2002-01-01

A goal of the GTX effort has been to demonstrate the feasibility of a single stage- to- orbit (SSTO) vehicle that delivers a small payload to low earth orbit. The small payload class was chosen in order to minimize the risk and cost of development of this revolutionary system. A preliminary design study by the GTX team has resulted in the current configuration that offers considerable promise for meeting the stated goal. The size and gross lift-off weight resulting from scaling the current design to closure however may be considered impractical for the small payload. In lieu of evolving the project's reference vehicle to a large-payload class, this paper offers the alternative of using solid-rocket motors in order to close the vehicle at a practical scale. This approach offers a near-term, quasi-reusable system that easily evolves to reusable SSTO following subsequent development and optimization. This paper presents an overview of the impact of the addition of SRM's to the GTX reference vehicle's performance and trajectory. The overall methods of vehicle modeling and trajectory optimization will also be presented. A key element in the trajectory optimization is the use of the program OTIS 3.10 that provides rapid convergence and a great deal of flexibility to the user. This paper will also present the methods used to implement GTX requirements into OTIS modeling.

SRM-Assisted Trajectory for the GTX Reference Vehicle

NASA Technical Reports Server (NTRS)

Riehl, John; Trefny, Charles; Kosareo, Daniel (Technical Monitor)

2002-01-01

A goal of the GTX effort has been to demonstrate the feasibility of a single stage-to-orbit (SSTO) vehicle that delivers a small payload to low earth orbit. The small payload class was chosen in order to minimize the risk and cost of development of this revolutionary system. A preliminary design study by the GTX team has resulted in the current configuration that offers considerable promise for meeting the stated goal. The size and gross lift-off weight resulting from scaling the current design to closure however may be considered impractical for the small payload. In lieu of evolving the project' reference vehicle to a large-payload class, this paper offers the alternative of using solid-rocket motors in order to close the vehicle at a practical scale. This approach offers a near-term, quasi-reusable system that easily evolves to reusable SSTO following subsequent development and optimization. This paper presents an overview of the impact of the addition of SRM's to the GTX reference vehicle#s performance and trajectory. The overall methods of vehicle modeling and trajectory optimization will also be presented. A key element in the trajectory optimization is the use of the program OTIS 3.10 that provides rapid convergence and a great deal of flexibility to the user. This paper will also present the methods used to implement GTX requirements into OTIS modeling.

On the consistency of tomographically imaged lower mantle slabs

NASA Astrophysics Data System (ADS)

Shephard, Grace E.; Matthews, Kara J.; Hosseini, Kasra; Domeier, Mathew

2017-04-01

Over the last few decades numerous seismic tomography models have been published, each constructed with choices of data input, parameterization and reference model. The broader geoscience community is increasingly utilizing these models, or a selection thereof, to interpret Earth's mantle structure and processes. It follows that seismically identified remnants of subducted slabs have been used to validate, test or refine relative plate motions, absolute plate reference frames, and mantle sinking rates. With an increasing number of models to include, or exclude, the question arises - how robust is a given positive seismic anomaly, inferred to be a slab, across a given suite of tomography models? Here we generate a series of "vote maps" for the lower mantle by comparing 14 seismic tomography models, including 7 s-wave and 7 p-wave. Considerations include the retention or removal of the mean, the use of a consistent or variable reference model, the statistical value which defines the slab "contour", and the effect of depth interpolation. Preliminary results will be presented that address the depth, location and degree of agreement between seismic tomography models, both for the 14 combined, and between the p-waves and s-waves. The analysis also permits a broader discussion of slab volumes and subduction flux. And whilst the location and geometry of slabs, matches some the documented regions of long-lived subduction, other features do not, illustrating the importance of a robust approach to slab identification.

Measuring Greenland Ice Mass Variation With Gravity Recovery and the Climate Experiment Gravity and GPS

NASA Technical Reports Server (NTRS)

Wu, Xiao-Ping

1999-01-01

The response of the Greenland ice sheet to climate change could significantly alter sea level. The ice sheet was much thicker at the last glacial maximum. To gain insight into the global change process and the future trend, it is important to evaluate the ice mass variation as a function of time and space. The Gravity Recovery and Climate Experiment (GRACE) mission to fly in 2001 for 5 years will measure gravity changes associated with the current ice variation and the solid earth's response to past variations. Our objective is to assess the separability of different change sources, accuracy and resolution in the mass variation determination by the new gravity data and possible Global Positioning System (GPS) bedrock uplift measurements. We use a reference parameter state that follows a dynamic ice model for current mass variation and a variant of the Tushingham and Peltier ICE-3G deglaciation model for historical deglaciation. The current linear trend is also assumed to have started 5 kyr ago. The Earth model is fixed as preliminary reference Earth model (PREM) with four viscoelastic layers. A discrete Bayesian inverse algorithm is developed employing an isotropic Gaussian a priori covariance function over the ice sheet and time. We use data noise predicted by the University of Texas and JPL for major GRACE error sources. A 2 mm/yr uplift uncertainty is assumed for GPS occupation time of 5 years. We then carry out covariance analysis and inverse simulation using GRACE geoid coefficients up to degree 180 in conjunction with a number of GPS uplift rates. Present-day ice mass variation and historical deglaciation are solved simultaneously over 146 grids of roughly 110 km x 110 km and with 6 time increments of 3 kyr each, along with a common starting epoch of the current trend. For present-day ice thickness change, the covariance analysis using GRACE geoid data alone results in a root mean square (RMS) posterior root variance of 2.6 cm/yr, with fairly large a priori uncertainties in the parameters and a Gaussian correlation length of 350 km. Simulated inverse can successfully recover most features in the reference present-day change. The RMS difference between them over the grids is 2.8 cm/yr. The RMS difference becomes 1.1 cm/yr when both are averaged with a half Gaussian wavelength of 150 km. With a fixed Earth model, GRACE alone can separate the geoid signals due to past and current load fairly well. Shown are the reference geoid signatures of direct and elastic effects of the current trend, the viscoelastic effect of the same trend starting from 5 kyr ago, the Post Glacial Rebound (PGR), and the predicted GRACE geoid error. The difference between the reference and inverse modeled total viscoelastic signatures is also shown. Although past and current ice mass variations are allowed the same spatial scale, their geoid signals have different spatial patterns. GPS data can contribute to the ice mass determination as well. Additional information is contained in the original.

Environmental Reference Series, Earth and Environmental Studies, Part II.

ERIC Educational Resources Information Center

Qutub, Musa, Comp.

Compiled in this reference work are bibliographic citations for books and articles dealing with the earth and environmental studies. Specific categories are geology, oceanography, meteorology, and astronomy. Items are indexed only by title but information about author, source, and date of publication is also noted. (BL)

Measurements of stratospheric NO, NO2, and N2O5 by ISAMS: Preliminary observations and data validation

NASA Technical Reports Server (NTRS)

Kerridge, Brian J.; Ballard, J.; Knight, R. J.; Stevens, A. D.; Reburn, J.; Morris, P.; Remedios, John J.; Taylor, Fredric W.

1994-01-01

The Improved Stratospheric and Mesospheric Sounder (ISAMS) is a multichannel radiometer and forms part of the science payload of the Upper Atmosphere Research Satellite (UARS). ISAMS measures infrared emissions from the Earth's atmosphere in several wavelength bands. Three such bands include emission from nitric oxide, nitrogen dioxide, and dinitrogen pentoxide. In this paper, we briefly discuss how the ISAMS instrument measures NO, NO2, and N2O5. We also present preliminary data from these channels and describe preliminary validation work.

A study of meteor spectroscopy and physics from earth-orbit: A preliminary survey into ultraviolet meteor spectra

NASA Technical Reports Server (NTRS)

Meisel, D. D.

1976-01-01

Preliminary data required to extrapolate available meteor physics information (obtained in the photographic, visual and near ultraviolet spectral regions) into the middle and far ultraviolet are presented. Wavelength tables, telluric attenuation factors, meteor rates, and telluric airglow data are summarized in the context of near-earth observation vehicle parameters using moderate to low spectral resolution instrumentation. Considerable attenuation is given to the problem of meteor excitation temperatures since these are required to predict the strength of UV features. Relative line intensities are computed for an assumed chondritic composition. Features of greatest predicted intensities, the major problems in meteor physics, detectability of UV meteor events, complications of spacecraft motion, and UV instrumentation options are summarized.

Software requirements flow-down and preliminary software design for the G-CLEF spectrograph

NASA Astrophysics Data System (ADS)

Evans, Ian N.; Budynkiewicz, Jamie A.; DePonte Evans, Janet; Miller, Joseph B.; Onyuksel, Cem; Paxson, Charles; Plummer, David A.

2016-08-01

The Giant Magellan Telescope (GMT)-Consortium Large Earth Finder (G-CLEF) is a fiber-fed, precision radial velocity (PRV) optical echelle spectrograph that will be the first light instrument on the GMT. The G-CLEF instrument device control subsystem (IDCS) provides software control of the instrument hardware, including the active feedback loops that are required to meet the G-CLEF PRV stability requirements. The IDCS is also tasked with providing operational support packages that include data reduction pipelines and proposal preparation tools. A formal, but ultimately pragmatic approach is being used to establish a complete and correct set of requirements for both the G-CLEF device control and operational support packages. The device control packages must integrate tightly with the state-machine driven software and controls reference architecture designed by the GMT Organization. A model-based systems engineering methodology is being used to develop a preliminary design that meets these requirements. Through this process we have identified some lessons that have general applicability to the development of software for ground-based instrumentation. For example, tasking an individual with overall responsibility for science/software/hardware integration is a key step to ensuring effective integration between these elements. An operational concept document that includes detailed routine and non- routine operational sequences should be prepared in parallel with the hardware design process to tie together these elements and identify any gaps. Appropriate time-phasing of the hardware and software design phases is important, but revisions to driving requirements that impact software requirements and preliminary design are inevitable. Such revisions must be carefully managed to ensure efficient use of resources.

77 FR 32631 - Public Utility District No. 1 of Klickitat County, Washington; Notice of Preliminary Permit...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-01

...-long earth embankment dam enclosing an upper reservoir; (2) an upper reservoir, with a surface area of... above mean sea level (msl); (3) a 295-foot- high, 5,870-foot-long earth embankment dam enclosing a lower... system and would use water from the Columbia River for initial fill and make-up water. The estimated...

75 FR 59706 - Medicine Bow Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... consist of the following: (1) A 9,200- foot-circumference, 60-foot-high earth or rockfilled embankment... feet mean sea level (msl); (2) a 1,480-foot-long, 210-foot-high earth and rockfill or concrete-face... characters, without prior registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment...

Dose in critical body organs in low Earth orbit

NASA Technical Reports Server (NTRS)

Wilson, J. W.; Cucinotta, F.

1984-01-01

Human exposure to trapped radiations in low Earth orbit (LEO) are evaluated on the basis of a simple approximation of the human geometry for spherical shell shields of varying thickness. A data base is presented that may be used to make preliminary assessment of the impact of radiation exposure constraints on human performance. A sample impact assessment is discussed.

The Effect of Verbal and Visuo-Spatial Abilities on the Development of Knowledge of the Earth

ERIC Educational Resources Information Center

Kikas, Eve

2006-01-01

Difficulties in students' understanding of the spherical model of the Earth have been shown in previous studies. One of the reasons for these difficulties lies in beliefs and preliminary knowledge that hinder the interpretation of the scientific knowledge, the other reason may lie in the low level of verbal and visuo-spatial abilities. The study…

Examination of global correlations in ground deformation for terrestrial reference frame estimation

NASA Astrophysics Data System (ADS)

Chin, T. M.; Abbondanza, C.; Argus, D. F.; Gross, R. S.; Heflin, M. B.; Parker, J. W.; Wu, X.

2016-12-01

The KALman filter for REFerence frames (KALREF, Wu et al. 2015) has been developed to produce terrestrial reference frame (TRF) solutions. TRFs consist of precise position coordinates and velocity vectors of terrestrial reference sites (with the geocenter as the origin) along with the Earth orientation parameters, and they are produced by combining decades worth of space geodetic data using site tie data. To perform the combination, KALREF relies on stochastic models of the geophysical processes that are causing the Earth's surface to deform and reference sites to be displaced. We are investigating application of the GRACE data to improve the KALREF stochastic models by determining spatial statistics of the deformation of the Earth's surface caused by mass loading. A potential target of improvement is the non-uniform distribution of the geodetic observation sites, which can introduce bias in TRF estimates of the geocenter. The global and relatively uniform coverage of the GRACE measurements is expected to be free of such bias and allow us to improve physical realism of the stochastic model. For such a goal, we examine the spatial correlations in ground deformation derived from several GRACE data sets.[Wu et al. 2015: Journal of Geophysical Research (Solid Earth) 120:3775-3802

Water vapor retrieval by LEO and GEO SAR: techniques and performance evaluation.

NASA Astrophysics Data System (ADS)

Fermi, Alessandro; Silvio Marzano, Frank; Monti Guarnieri, Andrea; Pierdicca, Nazzareno; Realini, Eugenio; Venuti, Giovanna

2016-04-01

The millimetric sensitivity of SAR interferometry has been proved fruitful in estimating water-vapor maps, that can then be processed into higher level ZWD and PWV products. In the paper, we consider two different SAR surveys: Low Earth Orbiting (LEO) SAR, like ESA Sentinel-1, and Geosynchronous Earth Orbiting SAR. The two system are complementary, where LEO coverage is world-wide, while GEO is regional. On the other hand, LEO revisit is daily-to weekly, whereas GEO provides images in minutes to hours. Finally, LEO synthetic aperture is so short, less than a second, that the water-vapor is mostly frozen, whereas in the long GEO aperture the atmospheric phase screen would introduce a total decorrelation, if not compensated for. In the paper, we first review the Differential Interferometric techniques to get differential delay maps - to be then converted into water-vapor products, and then evaluate the quality in terms of geometric resolution, sensitivity, percentage of scene coverage, revisit, by referring to L and C band system, for both LEO and GEO. Finally, we discuss an empirical model for time-space variogram, and show a preliminary validation by campaign conducted with Ground Based Radar, as a proxy of GEO-SAR, capable of continuous scanning wide areas (up to 15 km) with metric resolution.

Experimental constraints on the sound velocities of cementite Fe3C to core pressures

NASA Astrophysics Data System (ADS)

Chen, Bin; Lai, Xiaojing; Li, Jie; Liu, Jiachao; Zhao, Jiyong; Bi, Wenli; Ercan Alp, E.; Hu, Michael Y.; Xiao, Yuming

2018-07-01

Sound velocities of cementite Fe3C have been measured up to 1.5 Mbar and at 300 K in a diamond anvil cell using the nuclear resonant inelastic X-ray scattering (NRIXS) technique. From the partial phonon density of states (pDOS) and equation of state (EOS) of Fe3C, we derived its elastic parameters including shear modulus, compressional (VP) and shear-wave (VS) velocities to core pressures. A pressure-induced spin-pairing transition in the powdered Fe3C sample was found to occur gradually between 10 and 50 GPa by the X-ray Emission Spectroscopy (XES) measurements. Following the completion of the spin-pairing transition, the VP and VS of low-spin Fe3C increased with pressure at a markedly lower rate than its high-spin counterpart. Our results suggest that the incorporation of carbon in solid iron to form iron carbide phases, Fe3C and Fe7C3, could effectively lower the VS but respectively raise the Poisson's ratio by 0.05 and 0.07 to approach the seismically observed values for the Earth's inner core. The comparison with the preliminary reference Earth model (PREM) implies that an inner core composition containing iron and its carbon-rich alloys can satisfactorily explain the observed seismic properties of the inner core.

Relation between the celestial reference system and the terrestrial reference system of a rigid earth

NASA Astrophysics Data System (ADS)

Aoki, Shinko

The equations of motion for a rigid earth under the influence of the sun and moon are solved analytically up to the second-order perturbation, and the results are used to elucidate the relationship between the celestial and terrestrial reference systems. The derivations are given in detail, and consideration is given to celestial-ephemeris and instantaneous-rotation poles, wobble, the departure point as the origin of the local inertial system, the precession-nutation matrix, and techniques for improving the celestial reference system.

Teaching and Learning about the Earth. ERIC Digest.

ERIC Educational Resources Information Center

Lee, Hyonyong

This ERIC Digest investigates the earth and space science guidelines of the National Science Education Standards. These guidelines are frequently referred to as the earth system and include components such as plate tectonics, the water cycle, and the carbon cycle. This Digest describes the development of earth systems science and earth systems…

Specifications of a Mechanized Center for Information Services for a Public Library Reference Center. Final Report. Part 1, Preliminary Specification: Mechanized Information Services in Public Library Reference Centers.

ERIC Educational Resources Information Center

California Univ., Los Angeles. Inst. of Library Research.

This document presents preliminary specifications for a library-based Center for Information Services (CIS). Four sets of issues are covered: (1) data base inventory, providing a listing of magnetic tape data bases now available from national sources or soon to be so; (2) administrative issues, including the organization of the CIS within the…

Monitoring of Earth Rotation by VLBI

NASA Technical Reports Server (NTRS)

Ma., Chopo; Macmillan, D. S.

2000-01-01

Monitoring Earth rotation with Very Long Baseline Interferometry (VLBI) has unique potential because of direct access to the Celestial Reference System (CRF and Terrestrial Reference System (TRF) and the feasibility of re-analyzing the entire data set. While formal precision of better than 0.045 mas for pole and 0.002 ms for UT 1 has been seen in the best 24-hr data, the accuracy of the Earth Orientation Parameter (EOP) time series as a whole is subject to logistical, operational, analytical and conceptual constraints. The current issues related to the VLBI data set and the CORE program for greater time resolution such as analysis consistency, network jitter and reference frame stability will be discussed.

Mission requirements for a manned earth observatory. Task 2: Reference mission definition and analyiss, volume 2

NASA Technical Reports Server (NTRS)

1973-01-01

The mission requirements and conceptual design of manned earth observatory payloads for the 1980 time period are discussed. Projections of 1980 sensor technology and user data requirements were used to formulate typical basic criteria pertaining to experiments, sensor complements, and reference missions. The subjects discussed are: (1) mission selection and prioritization, (2) baseline mission analysis, (3) earth observation data handling and contingency plans, and (4) analysis of low cost mission definition and rationale.

Environmental Reference Series, Earth and Environment Studies, Part I.

ERIC Educational Resources Information Center

Qutub, Musa, Comp.

Compiled in this reference work are bibliographic citations for books, articles, films, and organizations dealing with the earth and environmental studies. In addition to the above topics of a general nature, specific categories include food, natural resources, origin of life, recycling, and wastes. Items are indexed only by title but information…

Terrestrial reference standard sites for postlaunch sensor calibration

USGS Publications Warehouse

Teillet, P.M.; Chander, G.

2010-01-01

In an era when the number of Earth observation satellites is rapidly growing and measurements from satellite sensors are used to address increasingly urgent global issues, often through synergistic and operational combinations of data from multiple sources, it is imperative that scientists and decision-makers are able to rely on the accuracy of Earth observation data products. The characterization and calibration of these sensors, particularly their relative biases, are vital to the success of the developing integrated Global Earth Observation System of Systems (GEOSS) for coordinated and sustained observations of the Earth. This can only reliably be achieved in the postlaunch environment through the careful use of observations by multiple sensor systems over common, well-characterized terrestrial targets (i.e., on or near the Earth's surface). Through greater access to and understanding of these vital reference standard sites and their use, the validity and utility of information gained from Earth remote sensing will continue to improve. This paper provides a brief overview of the use of reference standard sites for postlaunch sensor radiometric calibration from historical, current, and future perspectives. Emphasis is placed on optical sensors operating in the visible, near-infrared, and shortwave infrared spectral regions.

76 FR 25320 - Hawthorn Water LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-04

...-long earth embankment dam creating; (2) an upper reservoir with a surface area of 120 acres and an 6,000 acre-foot storage capacity; (3) a 80-foot-high, 2,800-foot-long earth embankment dam creating; (4... prior registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must...

76 FR 30327 - Reliable Storage 1 LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

...-high, 2,932-foot-long earth embankment dam; (2) an upper reservoir with a surface area of 27.5 acres and an 2,262 acre-foot storage capacity; (3) a 120-foot-high, 2,475-foot-long earth embankment dam..., using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your name...

77 FR 9229 - Reliable Storage 1 LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-16

...-long earth embankment dam; (2) an upper reservoir with a surface area of 100 acres and an 7,100 acre-foot storage capacity; (3) a 120-foot-high, 920-foot-long earth embankment dam creating; (4) a lower..., using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your name...

76 FR 25319 - Magnolia Water LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-04

...-long earth embankment dam creating; (2) an upper reservoir with a surface area of 85 acres and an 5,000 acre-foot storage capacity; (3) a 60-foot-high, 7,300-foot-long earth embankment dam creating; (4) a... characters, without prior registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment...

76 FR 30340 - Reliable Storage 1 LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

...-long earth embankment dam; (2) an upper reservoir with a surface area of 100 acres and an 7,100 acre-foot storage capacity; (3) a 120-foot-high, 7,430-foot-long earth embankment dam creating; (4) a lower... brief comments up to 6,000 characters, without prior registration, using the eComment system at http...

76 FR 30339 - Reliable Storage 1 LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

...-long earth embankment dam; (2) an upper reservoir with a surface area of 57.4 acres and an 4,563 acre-foot storage capacity; (3) a 180-foot-high, 323-foot-long earth embankment dam creating; (4) a lower... registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your...

77 FR 24947 - Cedar Creek Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-26

... consist of: (1) A 60- foot-high, 12,700-foot-long earth embankment upper dam; (2) an upper reservoir with... with a total capacity of 660.0 megawatts; (5) a 140- foot-high, 1,600-foot-long earth embankment lower... system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your name and contact...

75 FR 8319 - H2O Providers, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

... Storage Project, located on Brush Hollow Creek, near Penrose, in Fremont, Pueblo, and El Paso Counties...-foot-high, 4,900-foot-long earth and rockfill embankment; (3) a reserve reservoir that would store approximately 5,000 acre-feet, retained by a 100-foot- high, 1,400-foot-long earth and rockfill embankment and a...

Recovery of a geocentric reference frame using the present-day GPS system

NASA Technical Reports Server (NTRS)

Malla, Rajendra P.; Wu, Sien-Chong

1990-01-01

A geocentric reference frame adopts the center of mass of the earth as the origin of the coordinate axes. The center of mass of the earth is the natural and unambiguous origin of a geocentric satellite dynamical system. But in practice a kinematically obtained terrestrial reference frame may assume an origin other than the geocenter. The establishment of a geocentric reference frame, to which all relevant observations and results can be referred and in which geodynamic theories or models for the dynamic behavior of earth can be formulated, requires the ability to accurately recover a given coordinate frame origin offset from the geocenter. GPS measurements, because of their abundance and broad distribution, provide a powerful tool to obtain this origin offset in a short period of time. Two effective strategies have been devised. Data from the First Central And South America (Casa Uno) geodynamics experiment has been studied, in order to demonstrate the ability of recovering the geocenter location with present day GPS satellites and receivers.

Clouds and the Earth's Radiant Energy System (CERES)

NASA Technical Reports Server (NTRS)

Carman, Stephen L.; Cooper, John E.; Miller, James; Harrison, Edwin F.; Barkstrom, Bruce R.

1992-01-01

The CERES (Clouds and the Earth's Radiant Energy System) experiment will play a major role in NASA's multi-platform Earth Observing System (EOS) program to observe and study the global climate. The CERES instruments will provide EOS scientists with a consistent data base of accurately known fields of radiation and of clouds. CERES will investigate the important question of cloud forcing and its influence on the radiative energy flow through the Earth's atmosphere. The CERES instrument is an improved version of the ERBE (Earth Radiation Budget Experiment) broadband scanning radiometer flown by NASA from 1984 through 1989. This paper describes the science of CERES, presents an overview of the instrument preliminary design, and outlines the issues related to spacecraft pointing and attitude control.

77 FR 59394 - Wills Creek Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-27

..., Coshocton County, Ohio. The sole purpose of a preliminary permit, if issued, is to grant the permit holder... Lake which has a surface area of 11,450 acres at a normal lake elevation of 742 feet and a maximum storage capacity of 196,000 acre-feet; (2) a 1,950-foot-long, 87-foot-high earth fill dam; (3) a 100-foot...

A preliminary structural analysis of space-base living quarters modules to verify a weight-estimating technique

NASA Technical Reports Server (NTRS)

Grissom, D. S.; Schneider, W. C.

1971-01-01

The determination of a base line (minimum weight) design for the primary structure of the living quarters modules in an earth-orbiting space base was investigated. Although the design is preliminary in nature, the supporting analysis is sufficiently thorough to provide a reasonably accurate weight estimate of the major components that are considered to comprise the structural weight of the space base.

Preliminary Results of NASA's First Autonomous Formation Flying Experiment: Earth Observing-1 (EO-1)

NASA Technical Reports Server (NTRS)

Folta, David; Hawkins, Albin

2001-01-01

NASA's first autonomous formation flying mission is completing a primary goal of demonstrating an advanced technology called enhanced formation flying. To enable this technology, the Guidance, Navigation, and Control center at the Goddard Space Flight Center has implemented an autonomous universal three-axis formation flying algorithm in executive flight code onboard the New Millennium Program's (NMP) Earth Observing-1 (EO-1) spacecraft. This paper describes the mathematical background of the autonomous formation flying algorithm and the onboard design and presents the preliminary validation results of this unique system. Results from functionality assessment and autonomous maneuver control are presented as comparisons between the onboard EO-1 operational autonomous control system called AutoCon(tm), its ground-based predecessor, and a stand-alone algorithm.

Common Earth Science Misconceptions in Science Teaching

ERIC Educational Resources Information Center

King, Chris

2012-01-01

A survey of the Earth science content of science textbooks found a wide range of misconceptions. These are discussed in this article with reference to the published literature on Earth science misconceptions. Most misconceptions occurred in the "sedimentary rocks and processes" and "Earth's structure and plate tectonics"…

Earth's Outer Core Properties Estimated Using Bayesian Inversion of Normal Mode Eigenfrequencies

NASA Astrophysics Data System (ADS)

Irving, J. C. E.; Cottaar, S.; Lekic, V.

2016-12-01

The outer core is arguably Earth's most dynamic region, and consists of an iron-nickel liquid with an unknown combination of lighter alloying elements. Frequencies of Earth's normal modes provide the strongest constraints on the radial profiles of compressional wavespeed, VΦ, and density, ρ, in the outer core. Recent great earthquakes have yielded new normal mode measurements; however, mineral physics experiments and calculations are often compared to the Preliminary reference Earth model (PREM), which is 35 years old and does not provide uncertainties. Here we investigate the thermo-elastic properties of the outer core using Earth's free oscillations and a Bayesian framework. To estimate radial structure of the outer core and its uncertainties, we choose to exploit recent datasets of normal mode centre frequencies. Under the self-coupling approximation, centre frequencies are unaffected by lateral heterogeneities in the Earth, for example in the mantle. Normal modes are sensitive to both VΦ and ρ in the outer core, with each mode's specific sensitivity depending on its eigenfunctions. We include a priori bounds on outer core models that ensure compatibility with measurements of mass and moment of inertia. We use Bayesian Monte Carlo Markov Chain techniques to explore different choices in parameterizing the outer core, each of which represents different a priori constraints. We test how results vary (1) assuming a smooth polynomial parametrization, (2) allowing for structure close to the outer core's boundaries, (3) assuming an Equation-of-State and adiabaticity and inverting directly for thermo-elastic parameters. In the second approach we recognize that the outer core may have distinct regions close to the core-mantle and inner core boundaries and investigate models which parameterize the well mixed outer core separately from these two layers. In the last approach we seek to map the uncertainties directly into thermo-elastic parameters including the bulk modulus, its pressure derivative, and molar mass and volume, with particular attention paid to the (inherent) trade-offs between the different coefficients. We discuss our results in terms of added uncertainty to the light element composition of the outer core and the potential existence of anomalous structure near the outer core's boundaries.

Mars Energy Spectrum studies from Assimilated MCS data using the UK MGCM

NASA Astrophysics Data System (ADS)

Valeanu, Alexandru; Read, Peter; Wang, Yixiong; Lewis, Stephen; Montabone, Luca; Tabataba-Vakili, Fachreddin

2015-04-01

Introduction The energy spectrum (ES) analysis is a renowned tool for understanding the driving mechanisms behind atmospheric turbulence (Lindborg, 1998). We aim to investigate whether energy and enstrophy inertial ranges exist in the kinetic energy spectrum (KES), and to quantify the corresponding cascades (with their ranges), and relationship with the atmospheric forcing and energy dissipation scales. The calculation of the ES from observational data is known to be highly non-trivial due to the lack of global coverage in space and time. Gage and Nastrom (1984) were the first to overcome this problem for Earth but this has not so far been attempted for Mars. Our approach is to take the sparse observational data and assimilate it using a global numerical model. We present preliminary results using the Mars Climate Sounder (MCS) retrievals and the LMD-UK Mars GCM (MGCM). This was pioneered by Lewis and Read (1999). Methodology The equations we used to calculate the Eddy and Zonal Mean kinetic energies are derived from total KES formula presented in Lindborg and Augier (2013). Hence, adding the two spectra together, we obtain the full KES spectrum as presented in their paper. For the Available Potential Energy Spectrum (APES), we have used a preliminary simplified version of the approach presented in Lindborg and Augier (2013). The Energy Spectra To date we have assimilated the MCS data at the resolution of T31 (triangular truncation), hence the ES only spans up to total wavenumber 31. This encompasses a portion of the energy inertial range, which might be expected to manifest the -3 exponential law by analogy with the Earth (Gage & Nastrom, 1984). Features: - velocities and corresponding KEs are higher with increasing height compared to Earth, - "-3" slope is restricted to ~30 km altitude, suggesting an early departure from the enstrophy inertial range, - boundary layer velocities are similar to Earth References 1. Gage and Nastrom, A Climatology of Atmospheric Wavenumber Spectra of Wind and Temperature Observed by Commercial Aircraft. J. Atmosph. Sci., 42, pp. 950-960 (1984). 2. Lewis, S.R., Collins, M.,Read, P.L., Forget, F., Hourdin, F., Fournier, R., Hourdin, C., Talagrand, O. and Huot, J.-P., A climate database for Mars. J. Geophys. Res., 104, pp. 24177-24194 (1999). 3. Lindborg, E., Can the atmospheric kinetic energy spectrum be explained by two-dimensional turbulence? J. Fluid. Mech, 338, pp. 259-288 (1999). 4. Lindborg and Augier, A new Formulation of the Spectral Energy Budget of the Atmosphere, with Application to Two High-Resolution General Circulation Models J. Atmos. Sci., 70, pp.2293-2308 (2013).

47 CFR 25.103 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... or within the major portion of the Earth's atmosphere intended for communication: (1) With one or... 1525-1559 MHz space-to-Earth band and the 1626.5-1660.5 MHz Earth-to-space band, which are referred to... Service space-to-Earth band and the 14.0-14.5 GHz Fixed-Satellite Service Earth-to-space band. 17/24 GHz...

Box Tomography: An efficient tomographic method for imaging localized structures in the deep Earth

NASA Astrophysics Data System (ADS)

Masson, Yder; Romanowicz, Barbara

2017-04-01

The accurate imaging of localized geological structures inside the deep Earth is key to understand our planet and its history. Since the introduction of the Preliminary Reference Earth Model, many generations of global tomographic models have been developed and give us access to the 3D structure of the Earth's interior. The latest generation of global tomographic models has emerged with the development of accurate numerical wavefield computations in a 3D earth combined with access to enhanced HPC capabilities. These models have sharpened up mantle images and unveiled relatively small scale structures that were blurred out in previous generation models. Fingerlike structures have been found at the base of the oceanic asthenosphere, and vertically oriented broad low velocity plume conduits [1] extend throughout the lower mantle beneath those major hotspots that are located within the perimeter of the deep mantle large low shear velocity provinces (LLSVPs). While providing new insights into our understanding of mantle dynamics, the detailed morphology of these features requires further efforts to obtain higher resolution images. In recent years, we developed a theoretical framework [2][3] for the tomographic imaging of localised geological structures buried inside the Earth, where no seismic sources nor receivers are necessarily present. We call this "box tomography" [4]. The essential difference between box-tomography and standard tomographic methods is that the numerical modeling (i.e. the raytracing in travel time tomography and the wave propagation in waveform tomography or full waveform inversion) is completely confined within the small box-region imaged. Thus, box tomography is a lot more efficient than global tomography (i.e. where we invert for the velocity in the larger volume that encompasses all the sources and receivers), for imaging localised objects. We present 2D and 3D examples showing that box tomography can be employed for imaging structures present within the D'' region at the base of the mantle. Further, we show that box-tomography performs well even in the difficult situation where the velocity distribution in the mantle above the target structure is not known a-priori. REFERENCES [1] French, S. W. and B. Romanowicz (2015) Broad Plumes at the base of the mantle beneath major hotspots, Nature, 525, 95-99 [2] Masson, Y., Cupillard, P., Capdeville, Y., & Romanowicz, B. (2013). On the numerical implementation of time-reversal mirrors for tomographic imaging. Geophysical Journal International, ggt459. [3] Masson, Y., & Romanowicz, B. (2017). Fast computation of synthetic seismograms within a medium containing remote localized perturbations: a numerical solution to the scattering problem. Geophysical Journal International, 208(2), 674-692. [4] Masson, Y., & Romanowicz, B. (2017). Box Tomography: Localised imaging of remote targets buried in an unknown medium, a step forward for understanding key structures in the deep Earth. Geophysical Journal International, (under review).

Towards a Refined Realisation of the Terrestrial Reference System

NASA Astrophysics Data System (ADS)

Angermann, D.; Drewes, H.; Meisel, B.; Kruegel, M.; Tesmer, V.

2004-12-01

Global reference frames provide the framework for scientific investigations of the Earth's system (e.g. plate tectonics, sea level change, seasonal and secular loading signals, atmosphere dynamics, Earth orientation excitation), as well as for many practical applications (e.g. surveying and navigation). Today, space geodetic techniques allow to determine geodetic parameters (e.g. station positions, Earth rotation) with a precision of a few millimeters (or even better). However, this high accuracy is not reflected by current realisations of the terrestrial reference system. To fully exploit the potential of the space geodetic observations for investigations of various global and regional, short-term, seasonal and secular phenomena of the Earth's system, the reference frame must be realised with the highest accuracy, spatial and temporal consistency and stability over decades. Furthermore, future progress in Earth sciences will fundamentally depend on understanding the Earth as a system, into which the three areas of geodetic research (geometry/deformation, Earth rotation, gravity) are to be integrated. The presentation focusses on various aspects that must be considered for a refined realisation of the terrestrial reference system, such as the development of suitable methods for the combination of the contributing space geodetic observations, the realisation of the TRF datum and the parameterisation of site motions. For this purpose we investigated time series of station positions and datum parameters obtained from VLBI, SLR, GPS and DORIS solutions, and compared the results at co-location sites and with other studies. Furthermore, we present results obtained from a TRS realisation based on epoch (weekly/daily) normal equations with station positions and daily Earth Orientation Parameters (EOP) using five years (1999-2004) of VLBI, SLR, GPS and DORIS data. This refined approach has major advantages compared to past TRF realisations based on multi-year solutions with station positions at a given epoch and constant velocities, as for instance non-linear effects of site positions and datum parameters can be considered, and consistency between TRF and EOPs can be achieved. First results of this new approach are promising.

A test of general relativity using the LARES and LAGEOS satellites and a GRACE Earth gravity model: Measurement of Earth's dragging of inertial frames.

PubMed

Ciufolini, Ignazio; Paolozzi, Antonio; Pavlis, Erricos C; Koenig, Rolf; Ries, John; Gurzadyan, Vahe; Matzner, Richard; Penrose, Roger; Sindoni, Giampiero; Paris, Claudio; Khachatryan, Harutyun; Mirzoyan, Sergey

2016-01-01

We present a test of general relativity, the measurement of the Earth's dragging of inertial frames. Our result is obtained using about 3.5 years of laser-ranged observations of the LARES, LAGEOS, and LAGEOS 2 laser-ranged satellites together with the Earth gravity field model GGM05S produced by the space geodesy mission GRACE. We measure [Formula: see text], where [Formula: see text] is the Earth's dragging of inertial frames normalized to its general relativity value, 0.002 is the 1-sigma formal error and 0.05 is our preliminary estimate of systematic error mainly due to the uncertainties in the Earth gravity model GGM05S. Our result is in agreement with the prediction of general relativity.

Reference coordinate systems: An update. Supplement 11

NASA Technical Reports Server (NTRS)

Mueller, Ivan I.

1988-01-01

A common requirement for all geodetic investigations is a well-defined coordinate system attached to the earth in some prescribed way, as well as a well-defined inertial coordinate system in which the motions of the terrestrial frame can be monitored. The paper deals with the problems encountered when establishing such coordinate systems and the transformations between them. In addition, problems related to the modeling of the deformable earth are discussed. This paper is an updated version of the earlier work, Reference Coordinate Systems for Earth Dynamics: A Preview, by the author.

Relativistic theory for picosecond time transfer in the vicinity of Earth

NASA Technical Reports Server (NTRS)

Petit, G.; Wolf, P.

1994-01-01

The problem of light propagation is treated in a geocentric reference system with the goal of ensuring picosecond accuracy for time transfer techniques using electromagnetic signals in the vicinity of the Earth. We give an explicit formula for a one way time transfer, to be applied when the spatial coordinates of the time transfer stations are known in a geocentric reference system rotating with the Earth. This expression is extended, at the same accuracy level of one picosecond, to the special cases of two way and LASSO time transfers via geostationary satellites.

Earth Global Reference Atmospheric Model 2007 (Earth-GRAM07) Applications for the NASA Constellation Program

NASA Technical Reports Server (NTRS)

Leslie, Fred W.; Justus, C. G.

2008-01-01

Engineering models of the atmosphere are used extensively by the aerospace community for design issues related to vehicle ascent and descent. The Earth Global Reference Atmosphere Model version 2007 (Earth-GRAM07) is the latest in this series and includes a number of new features. Like previous versions, Earth-GRAM07 provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0 km to 27 km, thermodynamics and winds are based on the National Oceanic and Atmospheric Administration Global Upper Air Climatic Atlas (GUACA) climatology. For altitudes between 20 km and 120 km, the model uses data from the Middle Atmosphere Program (MAP). Above 120 km, EarthGRAM07 now provides users with a choice of three thermosphere models: the Marshall Engineering Thermosphere (MET-2007) model; the Jacchia-Bowman 2006 thermosphere model (JB2006); and the Naval Research Labs Mass Spectrometer, Incoherent Scatter Radar Extended Model (NRL MSIS E-OO) with the associated Harmonic Wind Model (HWM-93). In place of these datasets, Earth-GRAM07 has the option of using the new 2006 revised Range Reference Atmosphere (RRA) data, the earlier (1983) RRA data, or the user may also provide their own data as an auxiliary profile. Refinements of the perturbation model are also discussed which include wind shears more similar to those observed at the Kennedy Space Center than the previous version Earth-GRAM99.

Space-to-earth power transmission system

NASA Technical Reports Server (NTRS)

Stevens, G. H.; Schuh, R.

1976-01-01

A preliminary analysis was conducted to establish the requirements of a space-to-earth microwave power transmission system. The need for accurate phase control on the transmitter was established and methods for assessing the impact of power density and thermal constraints on system performance were demonstrated. Potential radio frequency interference was considered. The sensitivity of transmission system scale to variations in power source, transportation and orbital fabrication and assembly costs was also determined.

76 FR 74783 - Apache Hydro LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-01

... project would consist of the following: (1) A 210-foot-high, 1,610-foot-long earth fill dam; (2) a 20-foot... acre-foot storage capacity; (4) a 170-foot-high, 1,270.0-foot-long earth fill dam creating; (5) a lower... prior registration, using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must...

Feasibility of mining lunar resources for earth use: Circa 2000 AD. Volume 1: Summary

NASA Technical Reports Server (NTRS)

Nishioka, K.; Arno, R. D.; Alexander, A. D.; Slye, R. E.

1973-01-01

The feasibility of obtaining lunar minerals for terrestrial uses is examined. Preliminary results gave indications that it will not be economically feasible to mine, refine, and transport lunar materials to Earth for consumption. A broad systems approach was used to analyze the problem. It was determined that even though the procedure was not economically advisable, the concept for the operations is technically sound.

Atmospheric Correction Prototype Algorithm for High Spatial Resolution Multispectral Earth Observing Imaging Systems

NASA Technical Reports Server (NTRS)

Pagnutti, Mary

2006-01-01

This viewgraph presentation reviews the creation of a prototype algorithm for atmospheric correction using high spatial resolution earth observing imaging systems. The objective of the work was to evaluate accuracy of a prototype algorithm that uses satellite-derived atmospheric products to generate scene reflectance maps for high spatial resolution (HSR) systems. This presentation focused on preliminary results of only the satellite-based atmospheric correction algorithm.

Mission Architecture Comparison for Human Lunar Exploration

NASA Technical Reports Server (NTRS)

Geffre, Jim; Robertson, Ed; Lenius, Jon

2006-01-01

The Vision for Space Exploration outlines a bold new national space exploration policy that holds as one of its primary objectives the extension of human presence outward into the Solar System, starting with a return to the Moon in preparation for the future exploration of Mars and beyond. The National Aeronautics and Space Administration is currently engaged in several preliminary analysis efforts in order to develop the requirements necessary for implementing this objective in a manner that is both sustainable and affordable. Such analyses investigate various operational concepts, or mission architectures , by which humans can best travel to the lunar surface, live and work there for increasing lengths of time, and then return to Earth. This paper reports on a trade study conducted in support of NASA s Exploration Systems Mission Directorate investigating the relative merits of three alternative lunar mission architecture strategies. The three architectures use for reference a lunar exploration campaign consisting of multiple 90-day expeditions to the Moon s polar regions, a strategy which was selected for its high perceived scientific and operational value. The first architecture discussed incorporates the lunar orbit rendezvous approach employed by the Apollo lunar exploration program. This concept has been adapted from Apollo to meet the particular demands of a long-stay polar exploration campaign while assuring the safe return of crew to Earth. Lunar orbit rendezvous is also used as the baseline against which the other alternate concepts are measured. The first such alternative, libration point rendezvous, utilizes the unique characteristics of the cislunar libration point instead of a low altitude lunar parking orbit as a rendezvous and staging node. Finally, a mission strategy which does not incorporate rendezvous after the crew ascends from the Moon is also studied. In this mission strategy, the crew returns directly to Earth from the lunar surface, and is thus referred to as direct return. Figures of merit in the areas of safety and mission success, mission effectiveness, extensibility, and affordability are used to evaluate and compare the lunar orbit rendezvous, libration point rendezvous, and direct return architectures, and this paper summarizes the results of those assessments.

Low-cost thermal-IR imager for an Earth observation microsatellite

NASA Astrophysics Data System (ADS)

Oelrich, Brian D.; Underwood, Craig I.

2017-11-01

A new class of thermal infrared (TIR) Earth Observation (EO) data will become available with the flight of miniature TIR EO instruments in a multiple micro-satellite constellation. This data set will provide a unique service for those wishing to analyse trends or rapidly detect anomalous changes in the TIR characteristics of the Earth's surface or atmosphere (e.g. fire detection). Following a preliminary study of potential mission applications, uncooled commercial-off-the-shelf (COTS) technology was selected to form the basis of a low-cost, compact instrument capable of complementing existing visible and near IR EO capabilities on a sub-100kg Surrey micro-satellite. The preliminary 2-3 kg instrument concept has been designed to yield a 325 m ground sample distance over a 200 km swath width from a constellation altitude of 700 km. The radiometric performance, enhanced with time-delayed integration (TDI), is expected to yield a NETD less than 0.5 K for a 300 K ground scene. Fabrication and characterization of a space-ready instrument is planned for late 2004.

High resolution microwave spectrometer sounder (HIMSS), volume 1, book 2

NASA Technical Reports Server (NTRS)

1990-01-01

The following topics are presented with respect to the high resolution microwave spectrometer sounder (HIMSS) that is to be used as an instrument for NASA's Earth Observing System (EOS): (1) preliminary program plans; (2) contract end item (CEI) specification; and (3) the instrument interface description document. Under the preliminary program plans section, plans dealing with the following subject areas are discussed: spares, performance assurance, configuration management, software implementation, contamination, calibration management, and verification.

Conceptual Framework and Guidelines for Establishing Geographic Information Systems Capable of Integrating Natural Resources Data and Socio-Economic Data for Development-Oriented Planning, Monitoring and Research. (Preliminary Version).

ERIC Educational Resources Information Center

de Man, W. H. Erik, Ed.

This preliminary conceptual framework and the 23 related guidelines have been prepared by specialists drawn from both developed and developing nations as a joint project of the International Institute for Aerial Survey and Earth Sciences (ITC). The project was designed to analyze linkages between natural resource based data and certain types of…

Earth Rotation Parameters from DSN VLBI: 1994

NASA Technical Reports Server (NTRS)

Steppe, J. A.; Oliveau, S. H.; Sovers, O. J.

1994-01-01

In this report, Earth Rotation Parameter (ERP) estimates ahve been obtained from an analysis of Deep Space Network (DSN) VLBI data that directly aligns its celestial and terrestrial reference frames with those of the International Earth Rotation Service (IERS).

The Spaceguard Survey: Report of the NASA International Near-Earth-Object Detection Workshop

NASA Technical Reports Server (NTRS)

Morrison, David (Editor)

1992-01-01

Impacts by Earth-approaching asteroids and comets pose a significant hazard to life and property. Although the annual probability of the Earth being struck by a large asteroid or comet is extremely small, the consequences of such a collision are so catastrophic that it is prudent to assess the nature of the threat and to prepare to deal with it. The first step in any program for the prevention or mitigation of impact catastrophes must involve a comprehensive search for Earth-crossing asteroids and comets and a detailed analysis of their orbits. At the request of the U.S. Congress, NASA has carried out a preliminary study to define a program for dramatically increasing the detection rate of Earth-crossing objects, as documented in this workshop report.

The Effect of Rare Earth on the Structure and Performance of Laser Clad Coatings

NASA Astrophysics Data System (ADS)

Bao, Ruiliang; Yu, Huijun; Chen, Chuanzhong; Dong, Qing

Laser cladding is one kind of advanced surface modification technology and has the abroad prospect in making the wear-resistant coating on metal substrates. However, the application of laser cladding technology does not achieve the people's expectation in the practical production because of many defects such as cracks, pores and so on. The addiction of rare earth can effectively reduce the number of cracks in the clad coating and enhance the coating wear-resistance. In the paper, the effects of rare earth on metallurgical quality, microstructure, phase structure and wear-resistance are analyzed in turns. The preliminary discussion is also carried out on the effect mechanism of rare earth. At last, the development tendency of rare earth in the laser cladding has been briefly elaborated.

O-atom degradation mechanisms of materials

NASA Technical Reports Server (NTRS)

Coulter, Daniel R.; Liang, Ranty H.; Chung, Shirley Y.; Smith, Keri Oda; Gupta, Amitava

1987-01-01

The low Earth orbit environment is described and the critical issues relating to oxygen atom degradation are discussed. Some analytic techniques for studying the problem and preliminary results on the underlying degradation mechanisms are presented.

Thermal-envelope field measurements in an energy-efficient office/dormitory

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

Christian, J.E.

1982-01-01

A 345 m/sup 2/ earth-covered structure located at the Oak Ridge National Laboratory is the focus of a DOE sponsored building-envelope research project. To heat the office/dormitory building over the 1981-1982 heating season would cost $1.70/m/sup 2/ ($0.16/ft/sup 2/), assuming $0.07/kWh. The thermal-integrity factor is 0.016 kWh/m/sup 2/ /sup 0/C (2.8 Btu/ft/sup 2/ /sup 0/F). A preliminary DOE-II model estimates the monthly electric energy needs for heating within 5% of field data derived estimates. DOE-II building simulations suggest that this earth-covered/passively heated office dormitory saves 30% for space heating and 26% for cooling compared to an energy efficient above grademore » structure. A preliminary winter energy balance has been generated from data collected in February and March providing a fractional breakdown of thermal losses and gains. A number of the energy-conserving component performances have been isolated; earth-covered roof, bermed wall, and nonvented trombe wall. The earth-covered roof system showed an overall thermal transmittance of 0.18 W/m/sup 2///sup 0/C (R=31 hr ft/sup 2/ /sup 0/F/Btu). The thermocouple wells located in the earth surrounding the building indicate the additional energy savings of burying over berming. For one week in February the trombe wall produced a 50% greater net thermal gain to the building then south facing windows per equivalent unit area.« less

A long time span relativistic precession model of the Earth

NASA Astrophysics Data System (ADS)

Tang, Kai; Soffel, Michael H.; Tao, Jin-He; Han, Wen-Biao; Tang, Zheng-Hong

2015-04-01

A numerical solution to the Earth's precession in a relativistic framework for a long time span is presented here. We obtain the motion of the solar system in the Barycentric Celestial Reference System by numerical integration with a symplectic integrator. Special Newtonian corrections accounting for tidal dissipation are included in the force model. The part representing Earth's rotation is calculated in the Geocentric Celestial Reference System by integrating the post-Newtonian equations of motion published by Klioner et al. All the main relativistic effects are included following Klioner et al. In particular, we consider several relativistic reference systems with corresponding time scales, scaled constants and parameters. Approximate expressions for Earth's precession in the interval ±1 Myr around J2000.0 are provided. In the interval ±2000 years around J2000.0, the difference compared to the P03 precession theory is only several arcseconds and the results are consistent with other long-term precession theories. Supported by the National Natural Science Foundation of China.

EOS Reference Handbook 1999: A Guide to NASA's Earth Science Enterprise and the Earth Observing System

NASA Technical Reports Server (NTRS)

King, M. D. (Editor); Greenstone, R. (Editor)

2000-01-01

The content of this handbook includes Earth Science Enterprise; The Earth Observing System; EOS Data and Information System (EOSDIS); Data and Information Policy; Pathfinder Data Sets; Earth Science Information Partners and the Working Prototype-Federation; EOS Data Quality: Calibration and Validation; Education Programs; International Cooperation; Interagency Coordination; Mission Elements; EOS Instruments; EOS Interdisciplinary Science Investigations; and Points-of-Contact.

Using NASA's Reference Architecture: Comparing Polar and Geostationary Data Processing Systems

NASA Technical Reports Server (NTRS)

Ullman, Richard; Burnett, Michael

2013-01-01

The JPSS and GOES-R programs are housed at NASA GSFC and jointly implemented by NASA and NOAA to NOAA requirements. NASA's role in the JPSS Ground System is to develop and deploy the system according to NOAA requirements. NASA's role in the GOES-R ground segment is to provide Systems Engineering expertise and oversight for NOAA's development and deployment of the system. NASA's Earth Science Data Systems Reference Architecture is a document developed by NASA's Earth Science Data Systems Standards Process Group that describes a NASA Earth Observing Mission Ground system as a generic abstraction. The authors work within the respective ground segment projects and are also separately contributors to the Reference Architecture document. Opinions expressed are the author's only and are not NOAA, NASA or the Ground Projects' official positions.

Ancient and Medieval Earth in Armenia

NASA Astrophysics Data System (ADS)

Farmanyan, S. V.

2015-07-01

Humankind has always sought to recognize the nature of various sky related phenomena and tried to give them explanations. The purpose of this study is to identify ancient Armenians' pantheistic and cosmological perceptions, world view, notions and beliefs related to the Earth. The paper focuses on the structure of the Earth and many other phenomena of nature that have always been on a major influence on ancient Armenians thinking. In this paper we have compared the term Earth in 31 languages. By discussing and comparing Universe structure in various regional traditions, myths, folk songs and phraseological units we very often came across to "Seven Heavens" (Seven heavens is a part of religious cosmology found in many major religions such as Islam, Judaism, Hinduism and Christianity (namely Catholicism) and "Seven Earths". Armenians in their turn divided Earth and Heavens into seven layers. And in science too, both the Earth and the Heavens have 7 layers. The Seven Heavens refer to the layers of our atmosphere. The Seven Earths refer to the layers of the Earth (from core to crust), as well as seven continents. We conclude that the perception of celestial objects varies from culture to culture and preastronomy had a significant impact on humankind, particularly on cultural diversities.

EVAL system concept definition. Partial spacelab payload

NASA Technical Reports Server (NTRS)

1976-01-01

The preliminary design of an earth-viewing spacelab payload, with accommodations shared by both NASA and ESA is addressed. Mission parameters for this flight include a launch date of September 1981, an inclination of 57 deg, and an orbital altitude of 325 km. A seven-day mission is planned. The NASA portion of this payload is assigned to the EVAL (Earth Viewing Applications Laboratory) program. The ESA complement is designed as a multiuser payload.

A feasibility study of unmanned rendezvous and docking in Mars orbit: Midterm review

NASA Technical Reports Server (NTRS)

1974-01-01

The ascent, rendezvous, docking and sample transfer operations in a potential MSSR mission that uses the Mars orbital rendezvous mode are considered. In order that the design choices made for these operations remain compatible with the rest of the mission, the impact on the Earth launch, Mars landing and orbiting and Earth return phase are also being assessed. The selection and description of a preliminary baseline concept are presented.

An informative solution to a seismological inverse problem.

PubMed

Gilbert, F; Dziewonski, A; Brune, J

1973-05-01

Preliminary results are presented that infer that 2 sec should be added to the tabular values for P phases and 4 sec to the tabular values for S phases of seismic travel times. From seismic evidence, the radius of the inner core of the Earth is 1229-1250 km; the radius of the outer core is 3482-3485 km. Data are presented relating resolving power with error of measurement for the Earth's mantle.

Temperature profiles measurements in turbulent Rayleigh-Bénard convection by optical fibre system at the Barrel of II-menau

NASA Astrophysics Data System (ADS)

Drahotský, Jakub; Hanzelka, Pavel; Musilová, Věra; Macek, Michal; du Puits, Ronald; Urban, Pavel

2018-06-01

Modelling of large-scale natural (thermally-generated) turbulent flows (such as the turbulent convection in Earth's atmosphere, oceans, or Sun) is approached in laboratory experiments in the simplified model system called the Rayleigh-Bénard convection (RBC). We present preliminary measurements of vertical temperature profiles in the cell with the height of 4:7 m, 7:15m in diameter, obtained at the Barrel of Ilmenau (BOI), the worldwide largest experimental setup to study highly turbulent RBC, newly equipped with the Luna ODiSI-B optical fibre system. In our configuration, the system permits to measure the temperature with a high spatial resolution of 5mm along a very thin glass optical fibre with the length of 5m and seems to be perfectly suited for measurement of time series of instantaneous vertical temperature profiles. The system was supplemented with the two Pt100 vertically movable probes specially designed by us for reference temperature profiles measurements.

Solid earth science in the 1990s. Volume 2: Panel reports

NASA Technical Reports Server (NTRS)

1991-01-01

This is the second volume of a three-volume report. Volume 2, Panel Reports, outlines a plan for solid Earth science research for the next decade. The science panels addressed the following fields: plate motion and deformation, lithospheric structure and evolution, volcanology, Earth structure and dynamics, Earth rotation and reference frames, and geopotential fields.

Earth Viewing Applications Laboratory (EVAL). Instrument catalog

NASA Technical Reports Server (NTRS)

1976-01-01

There were 87 instruments described that are used in earth observation, with an additional 51 instruments containing references to programs and their major functions. These instruments were selected from such sources as: (1) earth observation flight program, (2) operational satellite improvement programs, (3) advanced application flight experiment program, (4) shuttle experiment definition program, and (5) earth observation aircraft program.

Effects of topography on the dune forming winds on Titan

NASA Astrophysics Data System (ADS)

Larson, Erik J.; Toon, O. B.; Friedson, A. J.

2013-10-01

Cassini observed hundreds of dune fields on Titan, nearly all of which lie in the tropics and suggest westerly (from west to east) winds dominate at the surface. Most GCMs however have obtained easterly surface winds in the tropics, seemingly contradicting the wind direction suggested by the dunes. This has led to an active debate in the community about the origin of the dune forming winds on Titan and their direction and modality. This discussion is mostly driven by a study of Earth dunes seen as analogous to Titan. One can find examples of dunes on Earth that fit several wind regimes. To date only one GCM, that of Tokano (2008, 2010), has presented detailed analysis of its near surface winds and their dune forming capabilities. Despite the bulk of the wind being easterly, this GCM produces faster westerlies at equinox, thus transporting sand to the east. Our model, the Titan CAM (Friedson et al. 2009), is unable to reproduce the fast westerlies. Our GCM has been updated to include realistic topography released by the Cassini radar team. Preliminary results suggest our tropical wind regime now has net westerly winds in the tropics, albeit weak. References: Tokano, T. 2008. Icarus 194, 243-262. Tokano, T. 2010. Aeolian Research 2, 113-127. Friedson, J. et al. 2009. Planet. Sp. Sci., 57, 1931-1949.

Global plate motion frames: Toward a unified model

NASA Astrophysics Data System (ADS)

Torsvik, Trond H.; Müller, R. Dietmar; van der Voo, Rob; Steinberger, Bernhard; Gaina, Carmen

2008-09-01

Plate tectonics constitutes our primary framework for understanding how the Earth works over geological timescales. High-resolution mapping of relative plate motions based on marine geophysical data has followed the discovery of geomagnetic reversals, mid-ocean ridges, transform faults, and seafloor spreading, cementing the plate tectonic paradigm. However, so-called "absolute plate motions," describing how the fragments of the outer shell of the Earth have moved relative to a reference system such as the Earth's mantle, are still poorly understood. Accurate absolute plate motion models are essential surface boundary conditions for mantle convection models as well as for understanding past ocean circulation and climate as continent-ocean distributions change with time. A fundamental problem with deciphering absolute plate motions is that the Earth's rotation axis and the averaged magnetic dipole axis are not necessarily fixed to the mantle reference system. Absolute plate motion models based on volcanic hot spot tracks are largely confined to the last 130 Ma and ideally would require knowledge about the motions within the convecting mantle. In contrast, models based on paleomagnetic data reflect plate motion relative to the magnetic dipole axis for most of Earth's history but cannot provide paleolongitudes because of the axial symmetry of the Earth's magnetic dipole field. We analyze four different reference frames (paleomagnetic, African fixed hot spot, African moving hot spot, and global moving hot spot), discuss their uncertainties, and develop a unifying approach for connecting a hot spot track system and a paleomagnetic absolute plate reference system into a "hybrid" model for the time period from the assembly of Pangea (˜320 Ma) to the present. For the last 100 Ma we use a moving hot spot reference frame that takes mantle convection into account, and we connect this to a pre-100 Ma global paleomagnetic frame adjusted 5° in longitude to smooth the reference frame transition. Using plate driving force arguments and the mapping of reconstructed large igneous provinces to core-mantle boundary topography, we argue that continental paleolongitudes can be constrained with reasonable confidence.

Celestial reference frames and the gauge freedom in the post-Newtonian mechanics of the Earth-Moon system

NASA Astrophysics Data System (ADS)

Kopeikin, Sergei; Xie, Yi

2010-11-01

We introduce the Jacobi coordinates adopted to the advanced theoretical analysis of the relativistic Celestial Mechanics of the Earth-Moon system. Theoretical derivation utilizes the relativistic resolutions on reference frames adopted by the International Astronomical Union (IAU) in 2000. The resolutions assume that the Solar System is isolated and space-time is asymptotically flat at infinity and the primary reference frame covers the entire space-time, has its origin at the Solar System barycenter (SSB) with spatial axes stretching up to infinity. The SSB frame is not rotating with respect to a set of distant quasars that are assumed to be at rest on the sky forming the International Celestial Reference Frame (ICRF). The second reference frame has its origin at the Earth-Moon barycenter (EMB). The EMB frame is locally inertial and is not rotating dynamically in the sense that equation of motion of a test particle moving with respect to the EMB frame, does not contain the Coriolis and centripetal forces. Two other local frames—geocentric and selenocentric—have their origins at the center of mass of Earth and Moon respectively and do not rotate dynamically. Each local frame is subject to the geodetic precession both with respect to other local frames and with respect to the ICRF because of their relative motion with respect to each other. Theoretical advantage of the dynamically non-rotating local frames is in a more simple mathematical description of the metric tensor and relative equations of motion of the Moon with respect to Earth. Each local frame can be converted to kinematically non-rotating one after alignment with the axes of ICRF by applying the matrix of the relativistic precession as recommended by the IAU resolutions. The set of one global and three local frames is introduced in order to decouple physical effects of gravity from the gauge-dependent effects in the equations of relative motion of the Moon with respect to Earth.

Use of global positioning system measurements to determine geocentric coordinates and variations in Earth orientation

NASA Technical Reports Server (NTRS)

Malla, R. P.; Wu, S.-C.; Lichten, S. M.

1993-01-01

Geocentric tracking station coordinates and short-period Earth-orientation variations can be measured with Global Positioning System (GPS) measurements. Unless calibrated, geocentric coordinate errors and changes in Earth orientation can lead to significant deep-space tracking errors. Ground-based GPS estimates of daily and subdaily changes in Earth orientation presently show centimeter-level precision. Comparison between GPS-estimated Earth-rotation variations, which are the differences between Universal Time 1 and Universal Coordinated Time (UT1-UTC), and those calculated from ocean tide models suggests that observed subdaily variations in Earth rotation are dominated by oceanic tidal effects. Preliminary GPS estimates for the geocenter location (from a 3-week experiment) agree with independent satellite laser-ranging estimates to better than 10 cm. Covariance analysis predicts that temporal resolution of GPS estimates for Earth orientation and geocenter improves significantly when data collected from low Earth-orbiting satellites as well as from ground sites are combined. The low Earth GPS tracking data enhance the accuracy and resolution for measuring high-frequency global geodynamical signals over time scales of less than 1 day.

Optical Navigation for the Orion Vehicle

NASA Technical Reports Server (NTRS)

Crain, Timothy; Getchius, Joel; D'Souza, Christopher

2008-01-01

The Orion vehicle is being designed to provide nominal crew transport to the lunar transportation stack in low Earth orbit, crew abort prior during transit to the moon, and crew return to Earth once lunar orbit is achieved. One of the design requirements levied on the Orion vehicle is the ability to return to the vehicle and crew to Earth in the case of loss of communications and command with the Mission Control Center. Central to fulfilling this requirement, is the ability of Orion to navigate autonomously. In low-Earth orbit, this may be solved with the use of GPS, but in cis-lunar and lunar orbit this requires optical navigation. This paper documents the preliminary analyses performed by members of the Orion Orbit GN&C System team.

GEOdetic Data assimilation and EStimation of references for climate change InvEstigation. An overall presentation of the French GEODESIE project

NASA Astrophysics Data System (ADS)

Coulot, David; Richard, Jean-Yves

2017-04-01

Many major indicators of climate change are monitored with space observations (sea level rise from satellite altimetry, ice melting from dedicated satellites, etc.). This monitoring is highly dependent on references (positions and velocities of ground observing instruments, orbits of satellites, etc.) that only geodesy can provide. The current accuracy of these references does not permit to fully support the challenges that the constantly evolving Earth system gives rise to, and can consequently limit the accuracy of these indicators. For this reason, in the framework of the Global Geodetic Observing System (GGOS), stringent requirements are fixed to the International Terrestrial Reference Frame (ITRF) for the next decade: an accuracy at the level of 1 mm and a stability at the level of 0.1 mm/yr. This means an improvement of the current quality of ITRF by a factor of 5-10. Improving the quality of the geodetic references is an issue which requires a thorough reassessment of the methodologies involved. The most relevant and promising method to improve this quality is the direct combination (Combination at Observation Level - COL) of the space-geodetic measurements used to compute the official references of the International Earth Rotation and Reference Systems Service (IERS). The GEODESIE project aims at (i) determining highly-accurate global and consistent references (time series of Terrestrial Reference Frames and Celestial Reference Frames, of Earth's Orientation Parameters, and orbits of Earth's observation satellites) and (ii) providing the geophysical and climate research communities with these references, for a better estimation of geocentric sea level rise, ice mass balance and on-going climate changes. Time series of sea levels computed from altimetric data and tide gauge records with these references (orbits of satellite altimeters, Terrestrial Reference Frames and related vertical velocities of stations) will also be provided. The geodetic references will be essential bases for Earth's observation and monitoring to support the challenges of the century. The geocentric time series of sea levels will permit to better apprehend (i) the drivers of the global mean sea level rise and of regional variations of sea level and (ii) the contribution of the global climate change induced by anthropogenic greenhouse gases emissions to these drivers. All the results and computation and quality assessment reports will be available on a Website designed and opened in the Summer of 2017. This project, supported by the French Agence Nationale de la Recherche (ANR) for the period 2017-2020, will be an unprecedented opportunity to provide the French Groupe de Recherche de Géodésie Spatiale (GRGS) with complete simulation and data processing capabilities to prepare the future arrival of space missions such as the European Geodetic Reference Antenna in SPace (E-GRASP) and to significantly contribute to the GGOS with accurate references.

Journal of Geophysical Research Publications: Community Characteristics

NASA Astrophysics Data System (ADS)

Pfirman, S. L.; Porter, A.

2009-12-01

Do earth science publications differ by subfield or gender? To figure this out we analyzed publications in JGR Atmosphere, Oceans, and Solid Earth for the year 2000. We assumed that the first author exerted controlling influence over publication characteristics and then we looked at the number of co-authors, number of institutions represented by co-author affiliations, page length of the article, number of references cited, number of subject categories represented in the cited references, number of times the article was cited, and the time between the date the article was submitted and the date when it was accepted for publication. We found that, within each field, there was remarkable similarity between the publications led by women and those led by men. Interesting differences showed up between subfields: for example, Solid Earth authors use more references than do authors publishing in Atmosphere or Oceans.

A functionally optimized hot-mix asphalt wearing course : part I : preliminary results.

DOT National Transportation Integrated Search

2009-01-01

The purpose of this report was to highlight the preliminary findings of the design, production, placement, and early life performance of a new generation open-graded surface course (also referred to as porous friction course [PFC]) for use in Virgini...

Cosmic dust flux on Earth inferred from the Concordia micrometeorite collection

NASA Astrophysics Data System (ADS)

Engrand, Cécile; Duprat, Jean; Dartois, Emmanuel; Godard, Marie; Delauche, Lucie

2017-04-01

The present extraterrestrial flux incoming to Earth is dominated by cosmic dust, i.e. micrometeorites in the 20-500 microns size range. Prior to atmospheric entry, the flux is estimated to ˜30 000 tons.yr-1 [1]. The proportion of this flux reaching the earth surface as dust particles is debated [e.g. 2]. Since 2000, we recover micrometeorites from ultraclean snow in the vicinity of the Dome C Concordia station in Antarctica. This region has a well-characterized and small precipitation rate (˜ 3.5 g of water per year) that allows collecting micrometeorites from large equivalent surfaces (> 100 m2.yrs) by sampling reasonable volumes of snow. The high efficiency and cleanliness of the collecting process at Dome C has enabled the recovery of several thousands of particles larger than ˜ 20 μm, constituting the Concordia micrometeorite collection [3]. The Concordia micrometeorites have a young terrestrial age of about 50 years. We characterized more than three thousand micrometeorites (both melted and unmelted particles) by secondary electron microscopy and classified them in the textural types defined in [4]. A preliminary flux value of 6,000 tons.yr-1 was given in [5] from the early Concordia collection examination. We now have better statistics to update this value. References: [1] Love S.G. and Brownlee D.E. (1993) Science 262, 550-553. [2] Peucker-Ehrenbrink B., et al. (2016) Elements 12, 191-196. [3] Duprat J., et al. (2007) Adv. Space Res. 39, 605-611. [4] Genge M.J., et al. (2008) Meteorit. Planet. Sci. 43, 497-515. [5] Duprat J., et al. (2006) Meteorit. Planet. Sci. 41 Suppl., A48 (#5239).

Preliminary Design and Analysis of the GIFTS Instrument Pointing System

NASA Technical Reports Server (NTRS)

Zomkowski, Paul P.

2003-01-01

The Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Instrument is the next generation spectrometer for remote sensing weather satellites. The GIFTS instrument will be used to perform scans of the Earth s atmosphere by assembling a series of field-of- views (FOV) into a larger pattern. Realization of this process is achieved by step scanning the instrument FOV in a contiguous fashion across any desired portion of the visible Earth. A 2.3 arc second pointing stability, with respect to the scanning instrument, must be maintained for the duration of the FOV scan. A star tracker producing attitude data at 100 Hz rate will be used by the autonomous pointing algorithm to precisely track target FOV s on the surface of the Earth. The main objective is to validate the pointing algorithm in the presence of spacecraft disturbances and determine acceptable disturbance limits from expected noise sources. Proof of concept validation of the pointing system algorithm is carried out with a full system simulation developed using Matlab Simulink. Models for the following components function within the full system simulation: inertial reference unit (IRU), attitude control system (ACS), reaction wheels, star tracker, and mirror controller. With the spacecraft orbital position and attitude maintained to within specified limits the pointing algorithm receives quaternion, ephemeris, and initialization data that are used to construct the required mirror pointing commands at a 100 Hz rate. This comprehensive simulation will also aid in obtaining a thorough understanding of spacecraft disturbances and other sources of pointing system errors. Parameter sensitivity studies and disturbance analysis will be used to obtain limits of operability for the GIFTS instrument. The culmination of this simulation development and analysis will be used to validate the specified performance requirements outlined for this instrument.

SLS-1 flight experiments preliminary significant results

NASA Technical Reports Server (NTRS)

1992-01-01

Spacelab Life Sciences-1 (SLS-1) is the first of a series of dedicated life sciences Spacelab missions designed to investigate the mechanisms involved in the physiological adaptation to weightlessness and the subsequent readaptation to 1 gravity (1 G). Hypotheses generated from the physiological effects observed during earlier missions led to the formulation of several integrated experiments to determine the underlying mechanisms responsible for the observed phenomena. The 18 experiments selected for flight on SLS-1 investigated the cardiovascular, cardiopulmonary, regulatory physiology, musculoskeletal, and neuroscience disciplines in both human and rodent subjects. The SLS-1 preliminary results gave insight to the mechanisms involved in the adaptation to the microgravity environment and readaptation when returning to Earth. The experimental results will be used to promote health and safety for future long duration space flights and, as in the past, will be applied to many biomedical problems encountered here on Earth.

Mission design for NISAR repeat-pass Interferometric SAR

NASA Astrophysics Data System (ADS)

Alvarez-Salazar, Oscar; Hatch, Sara; Rocca, Jennifer; Rosen, Paul; Shaffer, Scott; Shen, Yuhsyen; Sweetser, Theodore; Xaypraseuth, Peter

2014-10-01

The proposed spaceborne NASA-ISRO SAR (NISAR) mission would use the repeat-pass interferometric Synthetic Aperture Radar (InSAR) technique to measure the changing shape of Earth's surface at the centimeter scale in support of investigations in solid Earth and cryospheric sciences. Repeat-pass InSAR relies on multiple SAR observations acquired from nearly identical positions of the spacecraft as seen from the ground. Consequently, there are tight constraints on the repeatability of the orbit, and given the narrow field of view of the radar antenna beam, on the repeatability of the beam pointing. The quality and accuracy of the InSAR data depend on highly precise control of both orbital position and observatory pointing throughout the science observation life of the mission. This paper describes preliminary NISAR requirements and rationale for orbit repeatability and attitude control in order to meet science requirements. A preliminary error budget allocation and an implementation approach to meet these allocations are also discussed.

Ocean, Land and Meteorology Studies Using Space-Based Lidar Measurements

NASA Technical Reports Server (NTRS)

Hu,Yongxiang

2009-01-01

CALIPSO's main mission objective is studying the climate impact of clouds and aerosols in the atmosphere. CALIPSO also collects information about other components of the Earth's ecosystem, such as oceans and land. This paper introduces the physics concepts and presents preliminary results for the valueadded CALIPSO Earth system science products. These include ocean surface wind speeds, column atmospheric optical depths, ocean subsurface backscatter, land surface elevations, atmospheric temperature profiles, and A-train data fusion products.

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

Nugent, C. R.; Cutri, R. M.; Mainzer, A.

We present preliminary diameters and albedos for 7956 asteroids detected in the first year of the NEOWISE Reactivation mission. Of those, 201 are near-Earth asteroids and 7755 are Main Belt or Mars-crossing asteroids. 17% of these objects have not been previously characterized using the Near-Earth Object Wide-field Infrared Survey Explorer, or “NEOWISE” thermal measurements. Diameters are determined to an accuracy of ∼20% or better. If good-quality H magnitudes are available, albedos can be determined to within ∼40% or better.

Preliminary estimates of the quantities of rare-earth elements contained in selected products and in imports of semimanufactured products to the United States, 2010

USGS Publications Warehouse

Bleiwas, Donald I.; Gambogi, Joseph

2013-01-01

Rare-earth elements (REEs) are contained in a wide range of products of economic and strategic importance to the Nation. The REEs may or may not represent a significant component of that product by mass, value, or volume; however, in many cases, the embedded REEs are critical for the device’s function. Domestic sources of primary supply and the manufacturing facilities to produce products are inadequate to meet U.S. requirements; therefore, a significant percentage of the supply of REEs and the products that contain them are imported to the United States. In 2011, mines in China produced roughly 97 percent of the world’s supply of REEs, and the country’s production of these elements will likely dominate global supply until at least 2020. Preliminary estimates of the types and amount of rare-earth elements, reported as oxides, in semimanufactured form and the amounts used for electric vehicle batteries, catalytic converters, computers, and other applications were developed to provide a perspective on the Nation’s use of these elements. The amount of rare-earth metals recovered from recycling, remanufacturing, and reuse is negligible when the tonnage of products that contain REEs deposited in landfills and retained in storage is considered. Under favorable market conditions, the recovery of REEs from obsolete products could potentially displace a portion of the supply from primary sources.

Ground mapping resolution accuracy of a scanning radiometer from a geostationary satellite.

PubMed

Stremler, F G; Khalil, M A; Parent, R J

1977-06-01

Measures of the spatial and spatial rate (frequency) mapping of scanned visual imagery from an earth reference system to a spin-scan geostationary satellite are examined. Mapping distortions and coordinate inversions to correct for these distortions are formulated in terms of geometric transformations between earth and satellite frames of reference. Probabilistic methods are used to develop relations for obtainable mapping resolution when coordinate inversions are employed.

Toward Microsatellite Based Space Situational Awareness

NASA Astrophysics Data System (ADS)

Scott, L.; Wallace, B.; Sale, M.; Thorsteinson, S.

2013-09-01

The NEOSSat microsatellite is a dual mission space telescope which will perform asteroid detection and Space Situational Awareness (SSA) observation experiments on deep space, earth orbiting objects. NEOSSat was launched on 25 February 2013 into a 800 dawn-dusk sun synchronous orbit and is currently undergoing satellite commissioning. The microsatellite consists of a small aperture optical telescope, GPS receiver, high performance attitude control system, and stray light rejection baffle designed to reject stray light from the Sun while searching for asteroids with elongations 45 degrees along the ecliptic. The SSA experimental mission, referred to as HEOSS (High Earth Orbit Space Surveillance), will focus on objects in deep space orbits. The HEOSS mission objective is to evaluate the utility of microsatellites to perform catalog maintenance observations of resident space objects in a manner consistent with the needs of the Canadian Forces. The advantages of placing a space surveillance sensor in low Earth orbit are that the observer can conduct observations without the day-night interruption cycle experienced by ground based telescopes, the telescope is insensitive to adverse weather and the system has visibility to deep space resident space objects which are not normally visible from ground based sensors. Also, from a photometric standpoint, the microsatellite is able to conduct observations on objects with a rapidly changing observer position. The possibility of spin axis estimation on geostationary satellites may be possible and an experiment characterize spin axis of distant resident space objects is being planned. Also, HEOSS offers the ability to conduct observations of satellites at high phase angles which can potentially extend the trackable portion of space in which deep space objects' orbits can be monitored. In this paper we describe the HEOSS SSA experimental data processing system and the preliminary findings of the catalog maintenance experiments. The placement of a space based space surveillance sensor in low Earth orbit introduces tasking and image processing complexities such as cosmic ray rejection, scattered light from Earth's limb and unique scheduling limitations due to the observer's rapid positional change and we describe first-look microsatellite space surveillance lessons from this unique orbital vantage point..

Composition of the atmosphere at the surface of Mars - Detection of argon-36 and preliminary analysis

NASA Technical Reports Server (NTRS)

Owen, T.; Biemann, K.

1976-01-01

The composition of the Martian atmosphere was determined by the mass spectrometer in the molecular analysis experiment. The presence of argon and nitrogen was confirmed and a value of 1 to 2750 plus or minus 500 for the ratio of argon-36 to argon-40 was established. A preliminary interpretation of these results suggests that Mars had a slightly more massive atmosphere in the past, but that much less total outgassing has occurred on Mars than on earth.

Preliminary environmental assessment for the satellite power system (SPS). Revision 1. Volume 1. Executive summary

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

Not Available

1980-01-01

A preliminary assessment of the environmental impacts of the proposed satellite power system (SPS) is summarized here. In this system, satellites would collect solar energy in space, convert it to microwaves, and transmit the microwaves to receiving antennas (rectennas) on earth. At the rectennas, the microwaves would be converted to electricity. The assessment considers microwave and nonmicrowave effects on the terrestrial environment and human health, atmospheric effects, and disruption of communications and other electromagnetic systems.

Behaviour of Rare Earth Elements during the Earth's core formation

NASA Astrophysics Data System (ADS)

Faure, Pierre; Bouhifd, Mohamed Ali; Boyet, Maud; Hammouda, Tahar; Manthilake, Geeth

2017-04-01

Rare Earth Elements (REE) are classified in the refractory group, which means that they have a high temperature condensation and their volatility-controlled fractionation is limited to high-temperature processes. Anomalies have been measured for Eu, Yb and Sm, which are the REE with the lowest condensation temperatures in CAIs and chondrules (e.g. [1]). REE are particularly abundant in the sulfides of enstatite chondrites, 100 to 1000 times the CI value [e.g. 2,3], proving that these elements are not strictly lithophile under extremely reducing conditions. However by investigating experimentally the impact of Earth's core formation on the behavior of Sm and Nd, we have shown the absence of fractionation between Sm and Nd during the segregation of the metallic phase [4]. Recently, Wohlers and Wood [5] proposed that Nd and Sm could be fractionated in presence of a S-rich alloy phase. However, their results were obtained at pressure and temperature conditions below the plausible conditions of the Earth's core formation. Clearly, large pressure range needs to be covered before well-constrained model can be expected. Furthermore, our preliminary metal-silicate partitioning results show that Ce and Eu have higher metal/silicate partition coefficients than their neighboring elements, and that the presence of sulphur enhances the relative difference between partition coefficients. In this presentation, we will present and discuss new metal-silicate partition coefficients of all REE at a deep magma ocean at pressures ranging from those of the uppermost upper mantle ( 5 GPa) to a maximum pressure expected in the range of 20 GPa, temperatures ranging from 2500 to about 3000 K, and oxygen fugacities within IW-1 to IW-5 (1 to 5 orders of magnitude lower than the iron-wüstite buffer). We will discuss the effect of S, as well as the effect of H2O on the behaviour of REE during the Earth's core formation: recent models suggest that contrary to currently accepted beliefs, the presence of water during the formation of metallic core of terrestrial planets is very plausible [e.g. 6-8]. References [1] Pack et al. (2004) Science 303, 997-1000. [2] Crozaz and Lundberg (1995) Geochim. Cosmochim. Acta 59, 3817-3831. [3] Gannoun et al. (2011) Geochim. Cosmochim. Acta 75, 3269-3289. [4] Bouhifd et al. (2015) Earth Planet. Sci. Lett. 413, 158-166. [5] Wohlers and Wood (2015) Nature 520, 337-340. [6] Marty (2012) Earth Planet. Sci. Lett. 313-314, 56-66. [7] Morbidelli et al. (2000) Meteor. Planet. Sci. 1320, 1309-1320. [8] Sarafian et al. (2014 Science 346, 623-626.

Evaluation of advanced geopotential models for operational orbit determination

NASA Technical Reports Server (NTRS)

Radomski, M. S.; Davis, B. E.; Samii, M. V.; Engel, C. J.; Doll, C. E.

1988-01-01

To meet future orbit determination accuracy requirements for different NASA projects, analyses are performed using Tracking and Data Relay Satellite System (TDRSS) tracking measurements and orbit determination improvements in areas such as the modeling of the Earth's gravitational field. Current operational requirements are satisfied using the Goddard Earth Model-9 (GEM-9) geopotential model with the harmonic expansion truncated at order and degree 21 (21-by-21). This study evaluates the performance of 36-by-36 geopotential models, such as the GEM-10B and Preliminary Goddard Solution-3117 (PGS-3117) models. The Earth Radiation Budget Satellite (ERBS) and LANDSAT-5 are the spacecraft considered in this study.

Human factors. [in space colony environments

NASA Technical Reports Server (NTRS)

Billingham, J.

1977-01-01

Life aboard space habitats is considered with reference to physiological factors and self-government. Physiological concerns include the loss of bone structural strength, the long-term effects of zero-gravity, the role of inert gases in breathing, and the danger of slow cosmic-ray particles. With reference to the administration of space habitats, it is suggested that initially Intelsat might serve as a model for supranational sponsorship. Later it is envisioned that space habitats will have some autonomy but will still be subject to earth control; habitats will not wage war on earth or on each other; and that the habitats will be protected from any adverse developments that might occur on earth.

Comparison of Multiple Beam Coverage to Earth Coverage for a Maritime Satellite System

DOT National Transportation Integrated Search

1973-12-01

Preliminary tradeoff comparisons were analyzed for a possible baseline L-band maritime communications satellite system. Primary emphasis was given to major shipping routes with secondary coverage elsewhere. A low cost satellite configuration was post...

Sex- and Gender-Differences in Emotion: A Preliminary Examination.

ERIC Educational Resources Information Center

Emmers, Tara M.

This paper offers a preliminary examination of literature reviewing sex and gender differences in the five prototypic emotions of fear, anger, sadness, joy, and love. The paper notes that within the literature on sex and gender differences, the terms "sex" and "gender" are often erroneously referred to interchangeably…

76 FR 14906 - Laminated Woven Sacks From the People's Republic of China: Final Results of First Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-18

... has added several case numbers to the Case Reference file within the Automated Commercial Environment... Vietnam: Preliminary Results, Preliminary Partial Rescission and Final Partial Rescission of the Second... the Socialist Republic of Vietnam: Final Results and Final Partial Rescission of Antidumping Duty...

A ballistic mission to fly by Comet Halley

NASA Technical Reports Server (NTRS)

Boain, R. J.; Hastrup, R. C.

1980-01-01

The paper describes the available options, ballistic trajectory opportunities, and a preliminary reference trajectory that were selected as a basis for spacecraft design studies and programmatic planning for a Halley ballistic intercept mission in 1986. The paper also presents trajectory, performance, and navigation data which support the preliminary selection.

Target selection for a hypervelocity asteroid intercept vehicle flight validation mission

NASA Astrophysics Data System (ADS)

Wagner, Sam; Wie, Bong; Barbee, Brent W.

2015-02-01

Asteroids and comets have collided with the Earth in the past and will do so again in the future. Throughout Earth's history these collisions have played a significant role in shaping Earth's biological and geological histories. The planetary defense community has been examining a variety of options for mitigating the impact threat of asteroids and comets that approach or cross Earth's orbit, known as near-Earth objects (NEOs). This paper discusses the preliminary study results of selecting small (100-m class) NEO targets and mission analysis and design trade-offs for validating the effectiveness of a Hypervelocity Asteroid Intercept Vehicle (HAIV) concept, currently being investigated for a NIAC (NASA Advanced Innovative Concepts) Phase 2 study. In particular this paper will focus on the mission analysis and design for single spacecraft direct impact trajectories, as well as several mission types that enable a secondary rendezvous spacecraft to observe the HAIV impact and evaluate it's effectiveness.

User data dissemination concepts for earth resources

NASA Technical Reports Server (NTRS)

Davies, R.; Scott, M.; Mitchell, C.; Torbett, A.

1976-01-01

Domestic data dissemination networks for earth-resources data in the 1985-1995 time frame were evaluated. The following topics were addressed: (1) earth-resources data sources and expected data volumes, (2) future user demand in terms of data volume and timeliness, (3) space-to-space and earth point-to-point transmission link requirements and implementation, (4) preprocessing requirements and implementation, (5) network costs, and (6) technological development to support this implementation. This study was parametric in that the data input (supply) was varied by a factor of about fifteen while the user request (demand) was varied by a factor of about nineteen. Correspondingly, the time from observation to delivery to the user was varied. This parametric evaluation was performed by a computer simulation that was based on network alternatives and resulted in preliminary transmission and preprocessing requirements. The earth-resource data sources considered were: shuttle sorties, synchronous satellites (e.g., SEOS), aircraft, and satellites in polar orbits.

All-Sky Earth Occultation Observations with the Fermi Gamma-Ray Burst Monitor

NASA Technical Reports Server (NTRS)

Wilson-Hodge, C. A.; Beklen, E.; Bhat, P. N.; Briggs, M.; Camero-Arranz, A.; Case, G.; Jenke, P.; Chaplin, V.; Cherry, M.; Connaughton, V.;

Preliminary Results on the Gravitational Slingshot Effect and the Population of Hyperbolic Meteoroids at Earth

NASA Technical Reports Server (NTRS)

Wiegert, P. A.

2011-01-01

Interstellar meteoroids, solid particles arriving from outside our Solar System, are not easily distinguished from local meteoroids. A velocity above the escape velocity of the Sun is often used as an indicator of a possible interstellar origin. We demonstrate that the gravitational slingshot effect, resulting from the passage of local meteoroid near a planet, can produce hyperbolic meteoroids at the Earth s orbit with excess velocities comparable to those expected of interstellar meteoroids.

Preliminary Reports, Memoranda and Technical Notes of the Materials Research Council Summer Conference, La Jolla, California

DTIC Science & Technology

1984-07-01

Faurie U of Illinois 312-996-2141 A.D. Morrison Jet Propulsion Lab 213-354- 7200 A.R. Calawa Lincoln Lab, MIT 617-863-550C Ron Kerber DARPA 202-694...environment can only be assessed following extensive experimentation in space.2 mM Considering the failure of all efforts to suppress, during growth on earth ... earth because of constitutional supercooling effect. For oxide systems, the possibility exists to establish non-wetting configurations and thus to avoid

Post-Newtonian Reference Frames for Advanced Theory of the Lunar Motion and a New Generation of Lunar Laser Ranging

NASA Astrophysics Data System (ADS)

Xie, Yi; Kopeikin, Sergei Affiliaiton: AB(Department of Physics and Astronomy, University of Missouri, USA kopeikins@missouri.edu)

2010-08-01

We overview a set of post-Newtonian reference frames for a comprehensive study of the orbital dynamics and rotational motion of Moon and Earth by means of lunar laser ranging (LLR). We employ a scalar-tensor theory of gravity depending on two post-Newtonian parameters, and , and utilize the relativistic resolutions on reference frames adopted by the International Astronomical Union (IAU) in 2000. We assume that the solar system is isolated and space-time is asymptotically flat at infinity. The primary reference frame covers the entire space-time, has its origin at the solar-system barycenter (SSB) and spatial axes stretching up to infinity. The SSB frame is not rotating with respect to a set of distant quasars that are forming the International Celestial Reference Frame (ICRF). The secondary reference frame has its origin at the Earth-Moon barycenter (EMB). The EMB frame is locally-inertial and is not rotating dynamically in the sense that equation of motion of a test particle moving with respect to the EMB frame, does not contain the Coriolis and centripetal forces. Two other local frames geocentric (GRF) and selenocentric (SRF) have their origins at the center of mass of Earth and Moon respectively and do not rotate dynamically. Each local frame is subject to the geodetic precession both with respect to other local frames and with respect to the ICRF because of their relative motion with respect to each other. Theoretical advantage of the dynamically non-rotating local frames is in a more simple mathematical description. Each local frame can be aligned with the axes of ICRF after applying the matrix of the relativistic precession. The set of one global and three local frames is introduced in order to fully decouple the relative motion of Moon with respect to Earth from the orbital motion of the Earth-Moon barycenter as well as to connect the coordinate description of the lunar motion, an observer on Earth, and a retro-reflector on Moon to directly measurable quantities such as the proper time and the round-trip laser-light distance. We solve the gravity field equations and find out the metric tensor and the scalar field in all frames which description includes the post-Newtonian multipole moments of the gravitational field of Earth and Moon. We also derive the post-Newtonian coordinate transformations between the frames and analyze the residual gauge freedom.

Toward a Framework for Systematic Error Modeling of NASA Spaceborne Radar with NOAA/NSSL Ground Radar-Based National Mosaic QPE

NASA Technical Reports Server (NTRS)

Kirstettier, Pierre-Emmanual; Honh, Y.; Gourley, J. J.; Chen, S.; Flamig, Z.; Zhang, J.; Howard, K.; Schwaller, M.; Petersen, W.; Amitai, E.

2011-01-01

Characterization of the error associated to satellite rainfall estimates is a necessary component of deterministic and probabilistic frameworks involving space-born passive and active microwave measurement") for applications ranging from water budget studies to forecasting natural hazards related to extreme rainfall events. We focus here on the error structure of NASA's Tropical Rainfall Measurement Mission (TRMM) Precipitation Radar (PR) quantitative precipitation estimation (QPE) at ground. The problem is addressed by comparison of PR QPEs with reference values derived from ground-based measurements using NOAA/NSSL ground radar-based National Mosaic and QPE system (NMQ/Q2). A preliminary investigation of this subject has been carried out at the PR estimation scale (instantaneous and 5 km) using a three-month data sample in the southern part of US. The primary contribution of this study is the presentation of the detailed steps required to derive trustworthy reference rainfall dataset from Q2 at the PR pixel resolution. It relics on a bias correction and a radar quality index, both of which provide a basis to filter out the less trustworthy Q2 values. Several aspects of PR errors arc revealed and quantified including sensitivity to the processing steps with the reference rainfall, comparisons of rainfall detectability and rainfall rate distributions, spatial representativeness of error, and separation of systematic biases and random errors. The methodology and framework developed herein applies more generally to rainfall rate estimates from other sensors onboard low-earth orbiting satellites such as microwave imagers and dual-wavelength radars such as with the Global Precipitation Measurement (GPM) mission.

Sm-Nd isotopic compositions of LREE minerals for use as reference materials for in situ analysis by LA-MC-ICPMS

NASA Astrophysics Data System (ADS)

Fisher, C. M.; McFarlane, C. R.; Sylvester, P.; Hanchar, J. M.; Lam, R.; Schmitz, M. D.

2009-12-01

Recent work has demonstrated the possibility of obtaining both accurate and precise in situ Sm-Nd isotopic data in light rare earth enriched (LREE) accessory minerals including apatite, titanite, and monazite, using laser ablation-multicollector-inductively coupled plasma mass spectrometry (LA-MC-ICPMS). A distinct advantage of using LA-MC-ICPMS is that Sm-Nd isotopic data from these minerals can be determined in sub-grain domains potentially avoiding problems of isotopic mixing from inherited or xenocrystic components and allowing both valuable tracer isotope and geochronologic data to be obtained. However, a number of analytical obstacles complicate accurate Sm-Nd determination by LA-MC-ICPMS including mass bias corrections, the 144Sm isobaric interference on 144Nd, and potential offset (ca. 20-40 ppm) from thermal ionization mass spectrometry (TIMS) determination of similar materials. Thus, in order to verify Sm-Nd isotopic determination from unknowns, matrix-matched quality control standards (i.e., reference materials) must be developed to test the data handling protocol. This talk will present new Sm-Nd isotopic data determined by both TIMS as well as LA-MC-ICPMS of a number of natural potential reference minerals including Durango apatite, Fish Canyon titanite, Daibosatsu allanite, Trebilcock monazite, as well as a monazite from the Doi Inthanon core complex in northern Thailand. Our preliminary LA-MC-ICPMS results demonstrate that Durango apatite, Fish Canyon titanite, and Thailand monazite show both inter- and intra-grain homogeneity at current levels of precision (ca. 0.3-0.5 ɛNd) and close agreement with our TIMS data.

Study of a High-Energy Upper Stage for Future Shuttle Missions

NASA Technical Reports Server (NTRS)

Dressler, Gordon A.; Matuszak, Leo W.; Stephenson, David D.

2003-01-01

Space Shuttle Orbiters are likely to remain in service to 2020 or beyond for servicing the International Space Station and for launching very high value spacecraft. There is a need for a new STS-deployable upper stage that can boost certain Orbiter payloads to higher energy orbits, up to and including Earth-escape trajectories. The inventory of solid rocket motor Inertial Upper Stages has been depleted, and it is unlikely that a LOX/LH2-fueled upper stage can fly on Shuttle due to safety concerns. This paper summarizes the results of a study that investigated a low cost, low risk approach to quickly developing a new large upper stage optimized to fly on the existing Shuttle fleet. Two design reference missions (DRMs) were specified: the James Webb Space Telescope (JWST) and the Space Interferometry Mission (SIM). Two categories of upper stage propellants were examined in detail: a storable liquid propellant and a storable gel propellant. Stage subsystems 'other than propulsion were based largely on heritage hardware to minimize cost, risk and development schedule span. The paper presents the ground rules and guidelines for conducting the study, the preliminary conceptual designs margins, assessments of technology readiness/risk, potential synergy with other programs, and preliminary estimates of development and production costs and schedule spans. Although the Orbiter Columbia was baselined for the study, discussion is provided to show how the results apply to the remaining STS Orbiter fleet.

Reprocessing the Elliptical Orbiting Galileo Satellites E14 and E18: Preliminary Results

NASA Astrophysics Data System (ADS)

Männel, Benjamin

2017-04-01

In August 2014, the two Galileo satellites FOC-1 (E18) and FOC-2 (E14) were - due to a technical problem - launched into a wrong, elliptic orbit. In a recovery mission a series of orbit maneuvers were performed to raise the perigee to an altitude where both spacecrafts could be introduced to the Galileo navigation service. After this period of orbit maintenance both satellites started to transmit navigation signals at November 29, 2014 (E18) and March 17, 2015 (E14). However, as it was not possible to recover the nominal orbits due to propellant limitations, both spacecrafts orbit the Earth with a numerical eccentricity of 0.16 and an inclination of 50.2°. Very soon, it was assumed that both satellites could be highly useful for studies on general relativity, especially as the Galileo spacecrafts are equipped with very stable passive hydrogen masers. A prerequisite for dedicated studies in this field are highly accurate satellite orbits and clock corrections. Preliminary results for orbit and satellite clock determination will be presented based on an initial reprocessing over the past 2.5 years. The presentation focuses firstly on orbit modeling aspects with respect to the elliptically orbits. Secondly the derived clock corrections for the on-board passive clocks are assessed with respect to the reference clock at ground stations. The results will be discussed also with respect to the proposed Galileo-based studies on the gravitational redshift.

Work and Inertial Frames

NASA Astrophysics Data System (ADS)

Kaufman, Richard

2017-12-01

A fairly recent paper resolves a large discrepancy in the internal energy utilized to fire a cannon as calculated by two inertial observers. Earth and its small reaction velocity must be considered in the system so that the change in kinetic energy is calculated correctly. This paper uses a car in a similar scenario, but considers the work done by forces acting over distances. An analysis of the system must include all energy interactions, including the work done on the car and especially the (negative) work done on Earth in a moving reference frame. This shows the importance of considering the force on Earth and the distance Earth travels. For calculation of work in inertial reference frames, the center of mass perspective is shown to be useful. We also consider the energy requirements to efficiently accelerate a mass among interacting masses.

[Physiological effects of rare earth elements and their application in traditional Chinese medicine].

PubMed

Zhou, Jie; Guo, Lanping; Xiao, Wenjuan; Geng, Yanling; Wang, Xiao; Shi, Xin'gang; Dan, Staerk

2012-08-01

The process in the studies on physiological effects of rare earth elements in plants and their action mechanisms were summarized in the aspects of seed germination, photosynthesis, mineral metabolism and stress resistance. And the applications of rare earth elements in traditional Chinese medicine (TCM) in recent years were also overviewed, which will provide reference for further development and application of rare earth elements in TCM.

The Geolocation model for lunar-based Earth observation

NASA Astrophysics Data System (ADS)

Ding, Yixing; Liu, Guang; Ren, Yuanzhen; Ye, Hanlin; Guo, Huadong; Lv, Mingyang

2016-07-01

In recent years, people are more and more aware of that the earth need to treated as an entirety, and consequently to be observed in a holistic, systematic and multi-scale view. However, the interaction mechanism between the Earth's inner layers and outer layers is still unclear. Therefore, we propose to observe the Earth's inner layers and outer layers instantaneously on the Moon which may be helpful to the studies in climatology, meteorology, seismology, etc. At present, the Moon has been proved to be an irreplaceable platform for Earth's outer layers observation. Meanwhile, some discussions have been made in lunar-based observation of the Earth's inner layers, but the geolocation model of lunar-based observation has not been specified yet. In this paper, we present a geolocation model based on transformation matrix. The model includes six coordinate systems: The telescope coordinate system, the lunar local coordinate system, the lunar-reference coordinate system, the selenocentric inertial coordinate system, the geocentric inertial coordinate system and the geo-reference coordinate system. The parameters, lncluding the position of the Sun, the Earth, the Moon, the libration and the attitude of the Earth, can be acquired from the Ephemeris. By giving an elevation angle and an azimuth angle of the lunar-based telescope, this model links the image pixel to the ground point uniquely.

Earth Global Reference Atmospheric Model (Earth-GRAM) GRAM Virtual Meeting

NASA Technical Reports Server (NTRS)

White, Patrick

2017-01-01

What is Earth-GRAM? Provide monthly mean and standard deviation for any point in atmosphere; Monthly, Geographic, and Altitude Variation. Earth-GRAM is a C++ software package; Currently distributed as Earth-GRAM 2016. Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents. Used by engineering community because of ability to create dispersions inatmosphere at a rapid runtime; Often embedded in trajectory simulation software. Not a forecast model. Does not readily capture localized atmospheric effects.

Effect of alcohol references in music on alcohol consumption in public drinking places.

PubMed

Engels, Rutger C M E; Slettenhaar, Gert; ter Bogt, Tom; Scholte, Ron H J

2011-01-01

People are exposed to many references to alcohol, which might influence their consumption of alcohol directly. In a field experiment, we tested whether textual references to alcohol in music played in bars lead to higher revenues of alcoholic beverages. We created two databases: one contained songs referring to alcohol, the parallel database contained songs with matching artists, tempo, and energetic content, but no references to alcohol. Customers of three bars were exposed to either music textually referring to alcohol or to the control condition, resulting in 23 evenings in both conditions. Bartenders were instructed to play songs with references to alcohol (or not) during a period of 2 hours each of the evenings of interest. They were not blind to the experimental condition. The results showed that customers who were exposed to music with textual references to alcohol spent significantly more on alcoholic drinks compared to customers in the control condition. This pilot study provides preliminary evidence that alcohol-related lyrics directly affect alcohol consumption in public drinking places. Since our study is one of the first testing direct effects of music lyrics on consumption, our small-scale, preliminary study needs replication before firm conclusions can be drawn. Copyright © American Academy of Addiction Psychiatry.

Determination of the extragalactic-planetary frame tie from joint analysis of radio interferometric and lunar laser ranging measurements

NASA Technical Reports Server (NTRS)

Folkner, W. M.; Charlot, P.; Finger, M. H.; Williams, J. G.; Sovers, O. J.; Newhall, XX; Standish, E. M., Jr.

1994-01-01

Very Long Baseline Interferometry (VLBI) observations of extragalactic radio sources provide the basis for defining an accurate non-rotating reference frame in terms of angular positions of the sources. Measurements of the distance from the Earth to the Moon and to the inner planets provide the basis for defining an inertial planetary ephemeris reference frame. The relative orientation, or frame tie, between these two reference frames is of interest for combining Earth orientation measurements, for comparing Earth orientation results with theories referred to the mean equator and equinox, and for determining the positions of the planets with respect to the extragalactic reference frame. This work presents an indirect determination of the extragalactic-planetary frame tie from a combined reduction of VLBI and Lunar Laser Ranging (LLR) observations. For this determination, data acquired by LLR tracking stations since 1969 have been analyzed and combined with 14 years of VLBI data acquired by NASA's Deep Space Network since 1978. The frame tie derived from this joint analysis, with an accuracy of 0.003 sec, is the most accurate determination obtained so far. This result, combined with a determination of the mean ecliptic (defined in the rotating sense), shows that the mean equinox of epoch J2000 is offset from the x-axis of the extragalactic frame adopted by the International Earth Rotation Service for astrometric and geodetic applications by 0.078 sec +/- 0.010 sec along the y-direction and y 0.019 sec +/- 0.001 sec. along the z-direction.

Collation of earth resources data collected by ERIM airborne sensors

NASA Technical Reports Server (NTRS)

Hasell, P. G., Jr.

1975-01-01

Earth resources imagery from nine years of data collection with developmental airborne sensors is cataloged for reference. The imaging sensors include single and multiband line scanners and side-looking radars. The operating wavelengths of the sensors include ultraviolet, visible and infrared band scanners, and X- and L-band radar. Imagery from all bands (radar and scanner) were collected at some sites and many sites had repeated coverage. The multiband scanner data was radiometrically calibrated. Illustrations show how the data can be used in earth resource investigations. References are made to published reports which have made use of the data in completed investigations. Data collection sponsors are identified and a procedure described for gaining access to the data.

DSCOVR/EPIC Images and Science: A New Way to View the Entire Sunlit Earth From A Sun-Earth Lagrange-1 Orbit

NASA Astrophysics Data System (ADS)

Herman, J. R.; Marshak, A.; Szabo, A.

2015-12-01

The DSCOVR mission was launched into a Sun-Earth Lagrange-1 orbit 1.5 million kilometers from earth in February 2015 onboard a SpaceX Falcon-9 rocket. The solar wind and earth science instruments were tested during the 4.5 month journey to L-1. The first data were obtained during the June-July commissioning phase, which included the first moderate resolution (10 km) color images of the entire sunlit earth, color images of the Moon, and scientific data from 10 narrow band filters (317.5, 325, 340, 388, 443, 551, 680, 687.75, 764, and 779.5 nm). Three of these filters were used to construct the color images (443, 551, 680 nm) based on the average eye response histogram of the sunlit earth. This talk will discuss some of the issues involved in deriving science quality data for global ozone, the aerosol index (dust, smoke, and volcanic ash), cloud amounts and reflectivity, and cloud height (measured from the O2 A- and B-bands). As with most new satellites, the science data are preliminary.

47 CFR 25.109 - Cross-reference.

Code of Federal Regulations, 2011 CFR

2011-10-01

... licensed under this part: (a) Amateur Satellite Service, see 47 CFR part 97. (b) Ship earth stations in the Maritime Mobile Satellite Service, see 47 CFR part 83. (c) Ship earth stations in the Maritime Mobile...

47 CFR 25.109 - Cross-reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... licensed under this part: (a) Amateur Satellite Service, see 47 CFR part 97. (b) Ship earth stations in the Maritime Mobile Satellite Service, see 47 CFR part 83. (c) Ship earth stations in the Maritime Mobile...

47 CFR 25.109 - Cross-reference.

Code of Federal Regulations, 2010 CFR

2010-10-01

... licensed under this part: (a) Amateur Satellite Service, see 47 CFR part 97. (b) Ship earth stations in the Maritime Mobile Satellite Service, see 47 CFR part 83. (c) Ship earth stations in the Maritime Mobile...

An experience of science theatre: Earth Science for children

NASA Astrophysics Data System (ADS)

Musacchio, Gemma; Lanza, Tiziana; D'Addezio, Giuliana

2015-04-01

The present paper describes an experience of science theatre addressed to children of primary and secondary school, with the main purpose of explaining the Earth interior while raising awareness about natural hazard. We conducted the experience with the help of a theatrical company specialized in shows for children. Several performances have been reiterated in different context, giving us the opportunity of conducting a preliminary survey with public of different ages, even if the show was conceived for children. Results suggest that science theatre while relying on creativity and emotional learning in transmitting knowledge about the Earth and its hazard has the potential to induce in children a positive attitude towards the risks

Physical Education in Schools: Preliminary Findings of a Worldwide Survey. Part II.

ERIC Educational Resources Information Center

Hardman, Ken; Marshall, J. Joe

2000-01-01

This second in a two-part article summarizes the preliminary findings of a worldwide survey on physical education in schools. This part focuses on: resources (i.e., finances, facilities and equipment, and qualified teaching personnel); issues and trends in physical education; concluding comments; and selected references covering both parts of the…

PTSD and Impaired Eye Expression Recognition: A Preliminary Study

ERIC Educational Resources Information Center

Schmidt, Jakob Zeuthen; Zachariae, Robert

2009-01-01

This preliminary study examined whether posttraumatic stress disorder (PTSD) was related to difficulties in identifying the mental states of others in a group of refugees. Sixteen Bosnian refugees, referred to treatment in an outpatient treatment center for survivors of torture and war-related trauma in Denmark (CETT), were compared to 16 non-PTSD…

Environmental Scanning: Preliminary Findings of a Survey of CEO Information Seeking Behaviour in Two Canadian Industries.

ERIC Educational Resources Information Center

Auster, Ethel; Choo, Chun Wei

1992-01-01

Reports the preliminary results of a survey of the environmental scanning behavior of 207 chief executive officers (CEOs) in the Canadian publishing and telecommunications industries. Topics addressed include information sources, perceived source accessibility, perceived source quality, and frequency of source use. (16 references) (LRW)

High-Accuracy Ring Laser Gyroscopes: Earth Rotation Rate and Relativistic Effects

NASA Astrophysics Data System (ADS)

Beverini, N.; Di Virgilio, A.; Belfi, J.; Ortolan, A.; Schreiber, K. U.; Gebauer, A.; Klügel, T.

2016-06-01

The Gross Ring G is a square ring laser gyroscope, built as a monolithic Zerodur structure with 4 m length on all sides. It has demonstrated that a large ring laser provides a sensitivity high enough to measure the rotational rate of the Earth with a high precision of ΔΩE < 10-8. It is possible to show that further improvement in accuracy could allow the observation of the metric frame dragging, produced by the Earth rotating mass (Lense-Thirring effect), as predicted by General Relativity. Furthermore, it can provide a local measurement of the Earth rotational rate with a sensitivity near to that provided by the international system IERS. The GINGER project is intending to take this level of sensitivity further and to improve the accuracy and the long-term stability. A monolithic structure similar to the G ring laser is not available for GINGER. Therefore the preliminary goal is the demonstration of the feasibility of a larger gyroscope structure, where the mechanical stability is obtained through an active control of the geometry. A prototype moderate size gyroscope (GP-2) has been set up in Pisa in order to test this active control of the ring geometry, while a second structure (GINGERino) has been installed inside the Gran Sasso underground laboratory in order to investigate the properties of a deep underground laboratory in view of an installation of a future GINGER apparatus. The preliminary data on these two latter instruments are presented.

Viking bistatic radar observations of the hellas basin on Mars: preliminary results.

PubMed

Simpson, R A; Tyler, G L; Brenkle, J P; Sue, M

1979-01-05

Preliminary reduction of Viking bistatic radar data gives root-mean-square surface slopes in the Hellas basin on Mars of about 4 degrees on horizontal scales averaged over 10 centimeters to 100 meters. This roughness decreases slightly with position along the ground track, south to north. The dielectric constant in this area appears to be approximately 3.1, greater than the martian average. These values are characteristic of lunar maria and are similar to those found near the Viking lander site in Chryse with the use of Earth-based radar.

Preliminary orbit determination for lunar satellites.

NASA Technical Reports Server (NTRS)

Lancaster, E. R.

1973-01-01

Methods for the determination of orbits of artificial lunar satellites from earth-based range rate measurements developed by Koskela (1964) and Bateman et al. (1966) are simplified and extended to include range measurements along with range rate measurements. For illustration, a numerical example is presented.

Thermal Gradient Fining of Glass

NASA Technical Reports Server (NTRS)

Wilcox, W.

1983-01-01

Molten glass fined (cleared of bubbles) by heating with suitable temperature gradient, according to preliminary experiments. Temperature gradient produces force on gas bubbles trapped in molten glass pushing bubbles to higher temperature region where they are collected. Concept demonstrated in experiments on Earth and on rocket.

Inclusive Schools. Topical Bibliography on Inclusive Schools.

ERIC Educational Resources Information Center

Sorenson, Barbara, Comp.; Drill, Janet, Comp.

This abstract bibliography of approximately 200 references looks at various aspects of inclusive schools. References are a result of computer searches of three databases: the Educational Resources Information Center (ERIC), Exceptional Child Education Resources, and the Western Regional Resources Center. Preliminary information includes directions…

Gravitomagnetic Field of the Universe and Coriolis Force on the Rotating Earth

ERIC Educational Resources Information Center

Veto, B.

2011-01-01

The Machian effect of distant masses of the universe in the frame of reference of the rotating Earth is demonstrated using the gravitomagnetic approach of general relativity. This effect appears in the form of a gravitomagnetic Lorentz force acting on moving bodies on the Earth. The gravitomagnetic field of the universe--deduced from a simple…

Thermal envelope field measurements in an energy-efficient office and dormitory

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

Christian, J.E.

1983-04-01

A 345-m/sup 2/ earth-covered structure located at Oak Ridge National Laboratory is the focus of a DOE-sponsored building envelope research project. Based on field-measured data, heating the office and dormitory building over the 1981-1982 heating season cost $1.70/m/sup 2/ ($0.16/ft/sup 2/), assuming the cost of electricity to be $0.057/kWh. The building's thermal integrity factor is 0.016 kWh/m/sup 2/ /sup 0/C (2.8 Btu/ft/sup 2/ /sup 0/F). A preliminary DOE-2 model estimates the monthly electric energy needs for heating to be within 5% of our field data-derived estimates. DOE-2 building simulations suggest that this earth-covered, passively solar heated office dormitory saves 30%more » of the space heating and 26% of the cooling costs of an energy-efficient above grade structure. A preliminary winter energy balance has been generated from data collected in February and March and provides a fractional breakdown of thermal losses and gains. Performances have been isolated for several of the energy-conserving components: the earth-covered roof, the bermed wall, and the nonvented Trombe wall. The earth-covered roof system showed an overall thermal transmittance of 0.18 W/m/sup 2/ /sup 0/C (R = 31 h ft/sup 2/ /sup 0/F Btu/sup -1/). The thermocouple wells in the earth surrounding the building indicate that burying a wall is more energy efficient than berming. During one week in February, the Trombe wall produced a 50% greater net thermal gain to the building than an equivalent area of south-facing windows.« less

Global Data Spatially Interrelate System for Scientific Big Data Spatial-Seamless Sharing

NASA Astrophysics Data System (ADS)

Yu, J.; Wu, L.; Yang, Y.; Lei, X.; He, W.

2014-04-01

A good data sharing system with spatial-seamless services will prevent the scientists from tedious, boring, and time consuming work of spatial transformation, and hence encourage the usage of the scientific data, and increase the scientific innovation. Having been adopted as the framework of Earth datasets by Group on Earth Observation (GEO), Earth System Spatial Grid (ESSG) is potential to be the spatial reference of the Earth datasets. Based on the implementation of ESSG, SDOG-ESSG, a data sharing system named global data spatially interrelate system (GASE) was design to make the data sharing spatial-seamless. The architecture of GASE was introduced. The implementation of the two key components, V-Pools, and interrelating engine, and the prototype is presented. Any dataset is firstly resampled into SDOG-ESSG, and is divided into small blocks, and then are mapped into hierarchical system of the distributed file system in V-Pools, which together makes the data serving at a uniform spatial reference and at a high efficiency. Besides, the datasets from different data centres are interrelated by the interrelating engine at the uniform spatial reference of SDOGESSG, which enables the system to sharing the open datasets in the internet spatial-seamless.

The gravity field observations and products at IGFS

NASA Astrophysics Data System (ADS)

Barzaghi, Riccardo; Vergos, George; Bonvalot, Sylvain; Barthelmes, Franz; Reguzzoni, Mirko; Wziontek, Hartmut; Kelly, Kevin

2017-04-01

The International Gravity Field Service (IGFS) is a service of the International Association of Geodesy (IAG) that was established in 2003 at the IAG/IUGG General Assembly in Sapporo (Japan). This service aims at coordinating the actions of the IAG services related to the Earth gravity field, i.e. the Bureau Gravimétrique International (BGI), the International Service for the Geoid (ISG), the International Geodynamics and Earth Tides Service (IGETS), the International Center for Global Earth Models (ICGEM) and the International Digital Elevation Model Service (IDEMS). Also, via its Central Bureau hosted at the Aristotle University of Thessaloniki (Greece), IGFS provides a link to the Global Geodetic Observing System (GGOS) bureaus in order to communicate their requirements and recommendations to the IGFS-Centers. In this work, a presentation is given on the recent activities of the service, namely those related to the contributions to the implementation of: the International Height Reference System/Frame; the Global Geodetic Reference System/Frame; the new Global Absolute Gravity Reference System/Frame. Particularly, the impact that these activities have in improving the estimation of the Earth's gravity field, either at global and local scale, is highlighted also in the framework of GGOS.

First archaeointensity results from the historical period of Cambodia, Southeast Asia

NASA Astrophysics Data System (ADS)

Higa, J. T.; Cai, S.; Tauxe, L.; Hendrickson, M.

2017-12-01

Understanding variations of the geomagnetic field has applications regarding the behavior of the Earth's outer core, dating of archeological artifacts, and the phenomenon that shields life from solar radiation. However, archaeointensity studies of the Holocene have been mostly limited to localities in Europe and the Middle East; archaeomagnetic surveys from Southeast Asia are almost non-existent. This investigation aims to establish a secular variation curve of geomagnetic field intensity for Cambodia. We sampled ancient iron smelting mounds from the Khmer Empire, located in present day Cambodia, and are analyzing them for paleointensity. The specimens are thought to be from the historical period, likely between 1000-1500 CE. Our samples, which include furnace fragments, iron slag, and ceramic tuyères, contain magnetic minerals that record the paleointensity of Earth's magnetic field at the time it was fired. Using the IZZI paleointensity method (Yu et al., 2004), which gradually replaces the sample's natural remanent magnetization with a thermal remanent magnetization obtained in a known lab field, we can determine the geomagnetic intensities preserved in these specimens. Based on our preliminary experiments, the tuyères, and perhaps also the fresh slag, will in all likelihood yield the most ideal results. Following additional measurements from these best-fit samples, we will determine the paleointensities of Cambodia for the time period from which the artifacts originated. This will commence the establishment of regional geomagnetic reference curves in Southeast Asia and also improve the global model.

A preliminary design of interior structure and foundation of an inflatable lunar habitat

NASA Technical Reports Server (NTRS)

Yin, Paul K.

1989-01-01

A preliminary structural design and analysis of an inflatable habitat for installation on the moon was completed. The concept takes the shape of a sphere with a diameter of approximately 16 meters. The interior framing provides five floor levels and is enclosed by a spherical air-tight membrane holding an interior pressure of 14.7 psi (101.4kpa). The spherical habitat is to be erected on the lunar surface with the lower one third below grade and the upper two thirds covered with a layer of lunar regolith for thermal insulation and shielding against radiation and meteoroids. The total dead weight (earth weight) of the structural aluminum, which is of vital interest for the costly space transportation, is presented. This structural dead weight represents a preliminary estimate without including structural details. The design results in two versions: one supports the weight of the radiation shielding in case of deflation of the fabric enclosure and the other assumes that the radiation shielding is self supporting. To gain some indication of the amount of structural materials needed if the identical habitat were installed on Mars and Earth, three additional design versions were generated where the only difference is in gravity. These additional design versions are highly academic since the difference will be much more than in gravity alone. The lateral loading due to dust storms on Mars and wind loads on Earth are some examples. The designs under the lunar gravity are realistic. They may not be adequate for final material procurement and fabrication, however, as the connection details, among other reasons, may effect the sizes of the structural members.

Preliminary bioelectrical impedance analysis (BIA) equation for body composition assessment in young females from Colombia

NASA Astrophysics Data System (ADS)

Caicedo-Eraso, J. C.; González-Correa, C. H.; González-Correa, C. A.

2013-04-01

A previous study showed that reported BIA equations for body composition are not suitable for Colombian population. The purpose of this study was to develop and validate a preliminary BIA equation for body composition assessment in young females from Colombia, using hydrodensitometry as reference method. A sample of 30 young females was evaluated. Inclusion and exclusion criteria were defined to minimize the variability of BIA. Height, weight, BIA, residual lung volume (RV) and underwater weight (UWW) were measured. A preliminary BIA equation was developed (r2 = 0.72, SEE = 2.48 kg) by stepwise multiple regression with fat-free mass (FFM) as dependent variable and weight, height and impedance measurements as independent variables. The quality of regression was evaluated and a cross-validation against 50% of sample confirmed that results obtained with the preliminary BIA equation is interchangeable with results obtained with hydrodensitometry (r2 = 0.84, SEE = 2.62 kg). The preliminary BIA equation can be used for body composition assessment in young females from Colombia until a definitive equation is developed. The next step will be increasing the sample, including a second reference method, as deuterium oxide dilution (D2O), and using multi-frequency BIA (MF-BIA). It would also be desirable to develop equations for males and other ethnic groups in Colombia.

Contributions of satellite-determined gravity results in geodesy

NASA Technical Reports Server (NTRS)

Khan, M. A.

1974-01-01

Different forms of the theoretical gravity formula are summarized and methods of standardization of gravity anomalies obtained from satellite gravity and terrestrial gravity data are discussed in the context of three most commonly used reference figures, e.g., International Reference Ellipsoid, Reference Ellipsoid 1967, and Equilibrium Reference Ellipsoid. These methods are important in the comparison and combination of satellite gravity and gravimetric data as well as the integration of surface gravity data, collected with different objectives, in a single reference system. For ready reference, tables for such reductions are computed. Nature of the satellite gravity anomalies is examined to aid the geophysical and geodetic interpretation of these anomalies in terms of the tectonic features of the earth and the structure of the earth's crust and mantle. Computation of the Potsdam correction from satellite-determined geopotential is reviewed. The contribution of the satellite gravity results in decomposing the total observed gravity anomaly into components of geophysical interest is discussed. Recent work on the possible temporal variations in the geogravity field is briefly reviewed.

Aircraft navigation and surveillance analysis for a spherical earth

DOT National Transportation Integrated Search

2014-10-01

This memorandum addresses a fundamental function in surveillance and navigation analysis : quantifying the geometry of two or more locations relative to each other and to a spherical earth. Here, geometry refers to: (a) points (idealized lo...

Unraveling Students' Misconceptions about the Earth's Shape and Gravity.

ERIC Educational Resources Information Center

Sneider, Cary I.; Ohadi, Mark M.

1998-01-01

Presents a study designed to test the effectiveness of a constructivist-historical teaching strategy in changing students' misconceptions about the earth's shape and gravity at the upper elementary and middle school levels. Contains 27 references. (DDR)

The early Earth Observing System reference handbook: Earth Science and Applications Division missions, 1990-1997

NASA Technical Reports Server (NTRS)

1990-01-01

Prior to the launch of the Earth Observing System (EOS) series, NASA will launch and operate a wide variety of new earth science satellites and instruments, as well as undertake several efforts collecting and using the data from existing and planned satellites from other agencies and nations. These initiatives will augment the knowledge base gained from ongoing Earth Science and Applications Division (ESAD) programs. This volume describes three sets of ESAD activities -- ongoing exploitation of operational satellite data, research missions with upcoming launches between now and the first launch of EOS, and candidate earth probes.

Earth observing system: 1989 reference handbook

NASA Technical Reports Server (NTRS)

1989-01-01

NASA is studying a coordinated effort called the Mission to Planet Earth to understand global change. The goals are to understand the Earth as a system, and to determine those processes that contribute to the environmental balance, as well as those that may result in changes. The Earth Observing System (Eos) is the centerpiece of the program. Eos will create an integrated scientific observing system that will enable multidisciplinary study of the Earth including the atmosphere, oceans, land surface, polar regions, and solid Earth. Science goals, the Eos data and information system, experiments, measuring instruments, and interdisciplinary investigations are described.

ARCSTONE: Accurate Calibration of Lunar Spectral Reflectance from space

NASA Astrophysics Data System (ADS)

Young, C. L.; Lukashin, C.; Jackson, T.; Cooney, M.; Ryan, N.; Beverly, J.; Davis, W.; Nguyen, T.; Rutherford, G.; Swanson, R.; Kehoe, M.; Kopp, G.; Smith, P.; Woodward, J.; Carvo, J.; Stone, T.

2017-12-01

Calibration accuracy and consistency are key on-orbit performance metrics for Earth observing sensors. The accuracy and consistency of measurements across multiple instruments in low Earth and geostationary orbits are directly connected to the scientific understanding of complex systems, such as Earth's weather and climate. Recent studies have demonstrated the quantitative impacts of observational accuracy on the science data products [1] and the ability to detect climate change trends for essential climate variables (e.g., Earth's radiation budget, cloud feedback, and long-term trends in cloud parameters) [2, 3]. It is common for sensors to carry references for calibration at various wavelengths onboard, but these can be subject to degradation and increase mass and risk. The Moon can be considered a natural solar diffuser in space. Establishing the Moon as an on-orbit high-accuracy calibration reference enables broad intercalibration opportunities, as the lunar reflectance is time-invariant and can be directly measured by most Earth-observing instruments. Existing approaches to calibrate sensors against the Moon can achieve stabilities of a tenth of a percent over a decade, as demonstrated by the SeaWIFS. However, the current lunar calibration quality, with 5 - 10% bias, depends on the photometric model of the Moon [4]. Significant improvements in the lunar reference are possible and are necessary for climate-level absolute calibrations using the Moon. The ARCSTONE instrument will provide a reliable reference for high-accuracy on-orbit calibration for reflected solar instruments. An orbiting spectrometer flying on a CubeSat in low Earth orbit will provide lunar spectral reflectance with accuracy < 0.5% (k = 1), sufficient to establish an SI-traceable absolute lunar calibration standard for past, current, and future Earth weather and climate sensors. The ARCSTONE team will present the instrument design status and path forward for development, building, calibration and testing. [1] Lyapustin, A. Y. et al., 2014, Atmos. Meas. Tech., 7, pp. 4353 - 4365. [2] Wielicki, B. A., et al., 2013, Bull. Amer. Meteor. Soc., 94, pp. 1519 - 1539. [3] Shea, Y. L., et al., 2017 J. of Climate. [4] Kieffer, H. H., et al., 2005, The Astronomical J., v. 129, pp. 2887 - 2901.

USING ABIOTIC INDICATORS OF REFERENCE CONDITION AND BIOTIC INDICATORS OF CONDITION TO ASSESS GREAT RIVER ECOSYSTEMS

EPA Science Inventory

This presentation outlines the approach and preliminary assessment results for EMAP-GRE. The use of biological indicators and reference conditions for river assessments has implications for scientists, river managers, and state and tribal natural resource regulators.

Reflector and Shield Material Properties for Project Prometheus

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

J. Nash

2005-11-02

This letter provides updated reflector and shield preliminary material property information to support reactor design efforts. The information provided herein supersedes the applicable portions of Revision 1 to the Space Power Program Preliminary Reactor Design Basis (Reference (a)). This letter partially answers the request in Reference (b) to provide unirradiated and irradiated material properties for beryllium, beryllium oxide, isotopically enriched boron carbide ({sup 11}B{sub 4}C) and lithium hydride. With the exception of {sup 11}B{sub 4}C, the information is provided in Attachments 1 and 2. At the time of issuance of this document, {sup 11}B{sub 4}C had not been studied.

Global precipitation measurement (GPM) preliminary design

NASA Astrophysics Data System (ADS)

Neeck, Steven P.; Kakar, Ramesh K.; Azarbarzin, Ardeshir A.; Hou, Arthur Y.

2008-10-01

The overarching Earth science mission objective of the Global Precipitation Measurement (GPM) mission is to develop a scientific understanding of the Earth system and its response to natural and human-induced changes. This will enable improved prediction of climate, weather, and natural hazards for present and future generations. The specific scientific objectives of GPM are advancing: Precipitation Measurement through combined use of active and passive remote-sensing techniques, Water/Energy Cycle Variability through improved knowledge of the global water/energy cycle and fresh water availability, Climate Prediction through better understanding of surface water fluxes, soil moisture storage, cloud/precipitation microphysics and latent heat release, Weather Prediction through improved numerical weather prediction (NWP) skills from more accurate and frequent measurements of instantaneous rain rates with better error characterizations and improved assimilation methods, Hydrometeorological Prediction through better temporal sampling and spatial coverage of highresolution precipitation measurements and innovative hydro-meteorological modeling. GPM is a joint initiative with the Japan Aerospace Exploration Agency (JAXA) and other international partners and is the backbone of the Committee on Earth Observation Satellites (CEOS) Precipitation Constellation. It will unify and improve global precipitation measurements from a constellation of dedicated and operational active/passive microwave sensors. GPM is completing the Preliminary Design Phase and is advancing towards launch in 2013 and 2014.

Video observations, atmospheric path, orbit and fragmentation record of the fall of the Peekskill meteorite.

PubMed

Ceplecha, Z; Brown, P; Hawkes, R L; Wetherill, G; Beech, M; Mossman, K

1996-02-01

Large Near-Earth-Asteroids have played a role in modifying the character of the surface geology of the Earth over long time scales through impacts. Recent modeling of the disruption of large meteoroids during atmospheric flight has emphasized the dramatic effects that smaller objects may also have on the Earth's surface. However, comparison of these models with observations has not been possible until now. Peekskill is only the fourth meteorite to have been recovered for which detailed and precise data exist on the meteoroid atmospheric trajectory and orbit. Consequently, there are few constraints on the position of meteorites in the solar system before impact on Earth. In this paper, the preliminary analysis based on 4 from all 15 video recordings of the fireball of October 9, 1992 which resulted in the fall of a 12.4 kg ordinary chondrite (H6 monomict breccia) in Peekskill, New York, will be given. Preliminary computations revealed that the Peekskill fireball was an Earth-grazing event, the third such case with precise data available. The body with an initial mass of the order of 10(4) kg was in a pre-collision orbit with a = 1.5 AU, an aphelion of slightly over 2 AU and an inclination of 5 degrees. The no-atmosphere geocentric trajectory would have lead to a perigee of 22 km above the Earth's surface, but the body never reached this point due to tremendous fragmentation and other forms of ablation. The dark flight of the recovered meteorite started from a height of 30 km, when the velocity dropped below 3 km/s, and the body continued 50 km more without ablation, until it hit a parked car in Peekskill, New York with a velocity of about 80 m/s. Our observations are the first video records of a bright fireball and the first motion pictures of a fireball with an associated meteorite fall.

Different types of small volcanos on Venus

NASA Technical Reports Server (NTRS)

Slyuta, E. N.; Shalimov, I. V.; Nikishin, A. M.

1992-01-01

One of the studies of volcanic activity on Venus is the comparison of that with the analogous volcanic activity on Earth. The preliminary report of such a comparison and description of a small cluster of small venusian volcanos is represented in detail in this paper.

Evolution of a National Position Paper on Geological Education

ERIC Educational Resources Information Center

Paull, Richard A.

1978-01-01

Presents a preliminary position paper for future submission to the American Geological Institute (AGI). Addresses the problems of educating the decision-makers and lay public, improving earth science education in secondary schools, educating professional geoscientists, and continuing education and retraining of professional geologists. (MA)

Preliminary findings of the LDEF Materials Special Investigation Group

NASA Technical Reports Server (NTRS)

Stein, Bland A.; Pippin, H. Gary

1992-01-01

The retrieval of NASA's LDEF from low Earth orbit provided an opportunity for the study of long duration space environmental effects on materials. The five year, nine month flight of the LDEF greatly enhanced the potential value of most LDEF materials. NASA recognized this potential by forming the LDEF Space Environmental Effects on Materials Special Investigation Group (MSIG). Its goal is to explore the expanded materials analysis opportunities available in the LDEF structure and on experiment trays. The charter and scope of MSIG activities is presented, followed by an overview of the preliminary MSIG observations. These observations of low Earth orbit environmental effects on materials were made in-space during LDEF retrieval and during LDEF tray disintegration. Also presented are initial findings of lab analyses of LDEF materials. Included are effects of individual environmental parameters: atomic oxygen, ultraviolet radiation, meteoroid and debris impacts, thermal cycling, vacuum, and contamination, plus combined effects of these parameters. Materials considered include anodized aluminum, polymer matrix composites, polymer films, silvered Teflon thermal blankets, and a white thermal control paint.

Low concentration ratio solar array for low Earth orbit multi-100kW application. Volume 2: Drawings

NASA Technical Reports Server (NTRS)

Nalbandian, S. J.; French, E. P.

1982-01-01

A preliminary design effort directed toward a low concentration ratio photovoltaic array system based on 1984 technology and capable of delivering multi-hundred kilowatts (300 kW to 100 kW range) in low Earth orbit. The array system consists of two or more array modules each capable of delivering between 113 kW to 175 kW using silicon solar cells or gallium arsenide solar cells, respectively. The array module deployed area is 1320 square meters and consists of 4356 pyramidal concentrator elements. The module, when stowed in the Space Shuttle's payload bay, has a stowage volume of a cube with 3.24 meters on a side. The concentrator elements are sized for a geometric concentration ratio (GCR) of six with an aperture area of 0.5 meters x 0.5 meters. Drawings for the preliminary design configuration and for the test hardware that was fabricated for design evaluation and test are provided.

PRELIMINARY FACTOR ANALYSIS OF VISUAL COGNITION AND MEMORY. STUDIES IN CINE-PSYCHOMETRY, FINAL REPORT, PART I.

ERIC Educational Resources Information Center

SEIBERT, WARREN F.; AND OTHERS

PRELIMINARY ANALYSES WERE UNDERTAKEN TO DETERMINE THE POTENTIAL CONTRIBUTION OF MOTION PICTURE FILMS TO FACTOR ANALYTIC STUDIES OF HUMAN INTELLECT. OF PRIMARY CONCERN WERE THE OPERATIONS OF COGNITION AND MEMORY, FORMING TWO OF THE FIVE OPERATION COLUMNS OF GUILFORD'S "STRUCTURE OF INTELLECT." THE CORE REFERENCE FOR THE STUDY WAS DEFINED…

Preliminary Checklist of M.A. Theses and Ph.D. Dissertations Related to Asian American Studies in the UCLA Library.

ERIC Educational Resources Information Center

Lin, Che-Hwei, Comp.

Three hundred and twenty-five references are compiled in the preliminary checklist. Items are arranged alphabetically by author, and encompass research conducted in various disciplines about Chinese, Japanese, Filipino, Hawaiian, and Korean subgroups. Among the topical areas covered by the research studies are the following: cultural conflicts,…

Correlation signatures of wet soils and snows. [algorithm development and computer programming

NASA Technical Reports Server (NTRS)

Phillips, M. R.

1972-01-01

Interpretation, analysis, and development of algorithms have provided the necessary computational programming tools for soil data processing, data handling and analysis. Algorithms that have been developed thus far, are adequate and have been proven successful for several preliminary and fundamental applications such as software interfacing capabilities, probability distributions, grey level print plotting, contour plotting, isometric data displays, joint probability distributions, boundary mapping, channel registration and ground scene classification. A description of an Earth Resources Flight Data Processor, (ERFDP), which handles and processes earth resources data under a users control is provided.

Models of angular momentum input to a circumterrestrial swarm from encounters with heliocentric planetesimals

NASA Technical Reports Server (NTRS)

Herbert, F.; Davis, D. R.

1984-01-01

Preliminary experiments show that heliocentric planetesimals passing through the Earth environment possess significant angular momentum. However it also appears that these same planetesimals impacting a circularized circumterrestrial planetesimal swarm would likely remove angular momentum (though possibly increasing mean kinetic energy), presumably promoting both swarm infall upon the Earth and escape to heliocentric space. Only a distribution of highly eccentric satellite orbits with mean tangential velocities of a few tens of percent of local circular velocity would be immune against angular momentum loss to passing heliocentric planetesimals.

Human exposure in low Earth orbit

NASA Technical Reports Server (NTRS)

Wilson, J. W.; Cucinotta, F.

1984-01-01

Human exposure to trapped electrons and protons in low Earth orbit (LEO) is evaluated on a basis of a simple approximation of the human geometry for spherical shell shields of varying thickness. A data base is presented that may be used to make preliminary assessment of the impact of radiation exposure constraints on human performance. Detailed shielding studies should be performed before final design considerations. A sample impact assessment is discussed on the basis of presently accepted allowable exposure limits. A brief discussion is given on the anticipated impact of an ongoing reassessment of allowable exposure limits.

Ion engine propelled Earth-Mars cycler with nuclear thermal propelled transfer vehicle, volume 2

NASA Technical Reports Server (NTRS)

Meyer, Rudolf X.; Baker, Myles; Melko, Joseph

1994-01-01

The goal of this project was to perform a preliminary design of a long term, reusable transportation system between earth and Mars which would be capable of providing both artificial gravity and shelter from solar flare radiation. The heart of this system was assumed to be a Cycler spacecraft propelled by an ion propulsion system. The crew transfer vehicle was designed to be propelled by a nuclear-thermal propulsion system. Several Mars transportation system architectures and their associated space vehicles were designed.

To perform a gyro test of general relativity in a satellite and develop associated control technology

NASA Technical Reports Server (NTRS)

Fairbank, W. M.; Everitt, C. W. F.; Debra, D. B.

1977-01-01

A satellite configuration having two gyroscopes with axes parallel to the boresight of a telescope and two at right angles to the telescope and approximately parallel and perpendicular to the earth's axis is proposed for measuring geodetic precessions due to the earth's motion about the sun, higher order geodetic terms calculated from the earth's quadrapole mass moment (0.010 arc-sec/year in a 400 nautical mile polar orbit), and deflection by the sun of the starlight signal for the reference telescope. Data from the experiment also contain large periodic signals due to the annual and orbital aberrations of starlight which are useful in providing a built in reference signal of known amplitude for scaling the relativity signals, and should yield a singularly precise measurement of the parallax of the reference star. The development of the gyroscope and its readout system are discussed, as well as signal integration, drag-free control, and attitude control.

Earth orbit navigation study. Volume 2: System evaluation

NASA Technical Reports Server (NTRS)

1972-01-01

An overall systems evaluation was made of five candidate navigation systems in support of earth orbit missions. The five systems were horizon sensor system, unkown landmark tracking system, ground transponder system, manned space flight network, and tracking and data relay satellite system. Two reference missions were chosen: a low earth orbit mission and a transfer trajectory mission from low earth orbit to geosynchronous orbit. The specific areas addressed in the evaluation were performance, multifunction utilization, system mechanization, and cost.

Portuguese Students' Understanding at Ages 10-11 and 14-15 of the Origin and Nature of the Earth and the Development of Life.

ERIC Educational Resources Information Center

Marques, Luis; Thompson, David

1997-01-01

Uses interviews and a written questionnaire to probe students' ideas on the origin of earth and life on earth. A significant number of commonly held misconceptions were prevalent in the sample (N=493). Provides guidelines to assist learners in challenging existing views. Contains 64 references. (DDR)

Earth Observations taken by the STS-135 Crew

NASA Image and Video Library

2011-07-09

S135-E-006265 (9 July 2011) --- A nadir view from the Earth-orbiting space shuttle Atlantis, photographed by one of four STS-135 crewmembers, shows the southernmost part of Italy, referred to as the "boot." The astronauts were on the mission's second day of activity in Earth orbit, and the eve of docking day with the International Space Station. Photo credit: NASA

Terraforming the Moon: a Viable Step in the Colonization of the Solar System?

NASA Astrophysics Data System (ADS)

Renn, H. W.

2002-01-01

One potential option for the colonization of other celestial bodies is Terraforming. The latter involves, as a first step, the creation of a breathable, artificial atmosphere. While terraforming other planets, especially Mars, has been under discussion for several decades, applying the same concept to Earth's closest neighbor, namely the Moon, plays virtually no role in existing plans for space colonization. This paper investigates the technical and economical feasibility of supplying the Moon with an artificial atmosphere. Based on existing concepts for life support systems, essential requirements for an artificial Lunar atmosphere are defined. Various alternatives for the atmospheric composition are investigated and the parameters of a preferred `reference atmosphere' are described in detail. In order to assess the latter's habitability, particularly with respect to wind speeds and temperature cycles, the Moon's wind system and temperature field are analyzed by using a customized climate simulation model. Aspects of technical feasibility are evaluated and major obstacles are identified. Finally, various assessment criteria with particular respect to economical and ethical considerations are discussed and preliminary conclusions are presented.

Characterization of mesoscale convective systems over the eastern Pacific during boreal summer

NASA Astrophysics Data System (ADS)

Berthet, Sarah; Rouquié, Bastien; Roca, Rémy

2015-04-01

The eastern Pacific Ocean is one of the most active tropical disturbances formation regions on earth. This preliminary study is part of a broader project that aims to investigate how mesoscale convective systems (MCS) may be related to these synoptic disturbances with emphasis on local initiation of tropical depressions. As a first step, the main characteristics of the MCS over the eastern Pacific are documented with the help of the recently developed TOOCAN tracking algorithm (Fiolleau and Roca, 2013) applied to the infrared satellite imagery data from GOES-W and -E for the period JJAS 2012-2014. More specifically, the spatial distribution of the MCS population, the statistics of their spatial extensions and durations, as well as their trajectories and propagation speeds are summarized. In addition the environment of the MCS will be investigated using various Global Precipitation Mission datasets and the Megha-Tropiques/SAPHIR humidity microwave sounder derived products. Reference: Fiolleau T. and R. Roca, (2013), An Algorithm For The Detection And Tracking Of Tropical Mesoscale Convective Systems Using Infrared Images From Geostationary Satellite, Transactions on Geoscience and Remote Sensing, doi: 10.1109/TGRS.2012.2227762.

Sharpening advanced land imager multispectral data using a sensor model

USGS Publications Warehouse

Lemeshewsky, G.P.; ,

2005-01-01

The Advanced Land Imager (ALI) instrument on NASA's Earth Observing One (EO-1) satellite provides for nine spectral bands at 30m ground sample distance (GSD) and a 10m GSD panchromatic band. This report describes an image sharpening technique where the higher spatial resolution information of the panchromatic band is used to increase the spatial resolution of ALI multispectral (MS) data. To preserve the spectral characteristics, this technique combines reported deconvolution deblurring methods for the MS data with highpass filter-based fusion methods for the Pan data. The deblurring process uses the point spread function (PSF) model of the ALI sensor. Information includes calculation of the PSF from pre-launch calibration data. Performance was evaluated using simulated ALI MS data generated by degrading the spatial resolution of high resolution IKONOS satellite MS data. A quantitative measure of performance was the error between sharpened MS data and high resolution reference. This report also compares performance with that of a reported method that includes PSF information. Preliminary results indicate improved sharpening with the method reported here.

Using Enhanced Grace Water Storage Data to Improve Drought Detection by the U.S. and North American Drought Monitors

NASA Technical Reports Server (NTRS)

Houborg, Rasmus; Rodell, Matthew; Lawrimore, Jay; Li, Bailing; Reichle, Rolf; Heim, Richard; Rosencrans, Matthew; Tinker, Rich; Famiglietti, James S.; Svoboda, Mark;

Additional extensions to the NASCAP computer code, volume 2

NASA Technical Reports Server (NTRS)

Stannard, P. R.; Katz, I.; Mandell, M. J.

1982-01-01

Particular attention is given to comparison of the actural response of the SCATHA (Spacecraft Charging AT High Altitudes) P78-2 satellite with theoretical (NASCAP) predictions. Extensive comparisons for a variety of environmental conditions confirm the validity of the NASCAP model. A summary of the capabilities and range of validity of NASCAP is presented, with extensive reference to previously published applications. It is shown that NASCAP is capable of providing quantitatively accurate results when the object and environment are adequately represented and fall within the range of conditions for which NASCAP was intended. Three dimensional electric field affects play an important role in determining the potential of dielectric surfaces and electrically isolated conducting surfaces, particularly in the presence of artificially imposed high voltages. A theory for such phenomena is presented and applied to the active control experiments carried out in SCATHA, as well as other space and laboratory experiments. Finally, some preliminary work toward modeling large spacecraft in polar Earth orbit is presented. An initial physical model is presented including charge emission. A simple code based upon the model is described along with code test results.

Human Health and Performance Aspects of the Mars Design Reference Mission

NASA Technical Reports Server (NTRS)

Charles, John B.

2000-01-01

This paper will describe the current planning for exploration-class missions, emphasizing the medical, and human factors aspects of such expeditions. The details of mission architecture are still under study, but a typical Mars design reference mission comprises a six-month transit from Earth to Mar, eighteen months in residence on Mars, and a six-month transit back to Earth. Physiological stressors will include environmental factors such as prolonged exposure to radiation, weightlessness in transit, and hypogravity and a toxic atmosphere while on Mars. Psychological stressors will include remoteness from Earth, confinement, and potential interpersonal conflicts, all complicated by circadian alterations. Medical risks including trauma must also be considered. Results of planning for assuring human health and performance will be presented.

Rigorous Combination of GNSS and VLBI: How it Improves Earth Orientation and Reference Frames

NASA Astrophysics Data System (ADS)

Lambert, S. B.; Richard, J. Y.; Bizouard, C.; Becker, O.

2017-12-01

Current reference series (C04) of the International Earth Rotation and Reference Systems Service (IERS) are produced by a weighted combination of Earth orientation parameters (EOP) time series built up by combination centers of each technique (VLBI, GNSS, Laser ranging, DORIS). In the future, we plan to derive EOP from a rigorous combination of the normal equation systems of the four techniques.We present here the results of a rigorous combination of VLBI and GNSS pre-reduced, constraint-free, normal equations with the DYNAMO geodetic analysis software package developed and maintained by the French GRGS (Groupe de Recherche en GeÌodeÌsie Spatiale). The used normal equations are those produced separately by the IVS and IGS combination centers to which we apply our own minimal constraints.We address the usefulness of such a method with respect to the classical, a posteriori, combination method, and we show whether EOP determinations are improved.Especially, we implement external validations of the EOP series based on comparison with geophysical excitation and examination of the covariance matrices. Finally, we address the potential of the technique for the next generation celestial reference frames, which are currently determined by VLBI only.

Deriving a geocentric reference frame for satellite positioning and navigation

NASA Technical Reports Server (NTRS)

Malla, R. P.; Wu, S.-C.

1988-01-01

With the advent of Earth-orbiting geodetic satellites, nongeocentric datums or reference frames have become things of the past. Accurate geocentric three-dimensional positioning is now possible and is of great importance for various geodetic and oceanographic applications. While relative positioning accuracy of a few centimeters has become a reality using very long baseline interferometry (VLBI), the uncertainty in the offset of the adopted coordinate system origin from the geocenter is still believed to be on the order of 1 meter. Satellite laser ranging (SLR), however, is capable of determining this offset to better than 10 cm, but this is possible only after years of measurements. Global Positioning System (GPS) measurements provide a powerful tool for an accurate determination of this origin offset. Two strategies are discussed. The first strategy utilizes the precise relative positions that were predetermined by VLBI to fix the frame orientation and the absolute scaling, while the offset from the geocenter is determined from GPS measurements. Three different cases are presented under this strategy. The reference frame thus adopted will be consistent with the VLBI coordinate system. The second strategy establishes a reference frame by holding only the longitude of one of the tracking sites fixed. The absolute scaling is determined by the adopted gravitational constant (GM) of the Earth; and the latitude is inferred from the time signature of the Earth rotation in the GPS measurements. The coordinate system thus defined will be a geocentric Earth-fixed coordinate system.

Searching for artificial equilibrium points to place satellites "above and below" L3 in the Sun-Earth system

NASA Astrophysics Data System (ADS)

de Almeida, A. K., Jr.; Prado, A. F. B. A.; Sanchez, D. M.; Yokoyama, T.

2017-10-01

Regarding practical applications of L3 of the Sun-Earth system, there are few studies with the goal of placing a spacecraft at this point, or in orbit around it. One of the main problems in placing a spacecraft near this equilibrium point is the fact that it is located behind the Sun with respect to the Earth. The Sun would be blocking direct communication between the spacecraft and the Earth. The present research gives several options to solve this problem by using a solar sail to place one or two spacecraft above and/or below the Ecliptic plane. This sail could also be used for the mission itself, to collect energy or particles. By using an adequate size, location and attitude of the solar sail, the equilibrium point can be moved from its original location to allow communications between the spacecraft and the Earth. A preliminary study of a solar sail that uses this strategy is shown here.

Earth resources shuttle imaging radar. [systems analysis and design analysis of pulse radar for earth resources information system

NASA Technical Reports Server (NTRS)

1975-01-01

A report is presented on a preliminary design of a Synthetic Array Radar (SAR) intended for experimental use with the space shuttle program. The radar is called Earth Resources Shuttle Imaging Radar (ERSIR). Its primary purpose is to determine the usefulness of SAR in monitoring and managing earth resources. The design of the ERSIR, along with tradeoffs made during its evolution is discussed. The ERSIR consists of a flight sensor for collecting the raw radar data and a ground sensor used both for reducing these radar data to images and for extracting earth resources information from the data. The flight sensor consists of two high powered coherent, pulse radars, one that operates at L and the other at X-band. Radar data, recorded on tape can be either transmitted via a digital data link to a ground terminal or the tape can be delivered to the ground station after the shuttle lands. A description of data processing equipment and display devices is given.

Book Review: Precession, Nutation, and Wobble of the Earth

NASA Astrophysics Data System (ADS)

Sterken, Christiaan; Dehant, V.; Mathews, P. M.

2016-10-01

This great book describes and explains observational and computational aspects of three apparently tiny changes in the Earth's motion and orientation, viz., precession, nutation, and wobble. The three introductory chapters of this book present fundamental definitions, elementary geodetic theory, and celestial/terrestrial reference systems - including transformations between reference frames. The next chapter on observational techniques describes the principle of accurate measurements of the orientation of the Earth's axis, as obtained from measurements of extra-galactic radio sources using Very Long Baseline Interferometry and GPS observations. Chapter 5 handles precession and nutation of the rigid Earth (i.e., a celestial body that cannot, by definition, deform) and the subsequent chapter takes deformation into consideration, viz., the effect of a centrifugal force caused by a constant-rate rotation that causes the Earth's shape and structure to become ellipsoidal. Deformations caused by external solar-system bodies are discussed in terms of deformability parameters. The next three chapters handle additional complex deviations: non-rigid Earth and more general Earth models, anelastic Earth parameters, and the effects of the fluid layers (i.e., ocean and atmosphere) on Earth rotation. Chapter 10 complements Chapter 7 with refinements that take into account diverse small effects such as the effect of a thermal conductive layer at the top of the core, Core Mantle and Inner Boundary coupling effects on nutation, electromagnetic coupling, and so-called topographic coupling. Chapter 11 covers comparison of observation and theory, and tells us that the present-date precision of the nutation theory is at the level of milliarcseconds in the time domain, and of a tenth of a microsecond in the frequency domain (with some exceptions). This chapter is followed by a 25-page chapter of definitions of equator, equinox, celestial intermediate pole and origin, stellar angle, universal time, and more. Chapter 13 treats the planet Mars, as it is also rapidly rotating, has an equatorial bulge and an obliquity that is comparable to that of the Earth. The last chapter is followed by three Appendices, viz., Rotation representation, Clairaut theory and Definitions of equinoxes. Appendix A deals with rotation vector and rotation matrix, specifically applied to small angles, such as in the case of rotation from change of pole position. Appendix B expresses the Earth's gravitational potential, and the first-order hypothesis that the Earth is in hydrostatic equilibrium, and that its uniformly-rotating surface is an equipotential corresponding to the mean sea level. Appendix C presents a set of definitions of equinoxes. This book is extremely well documented with more than 50 pages of references that are very up to date. The illustrations (exclusively line art diagrams) are all of good quality and the data tables are rich and well formatted. The language is clear and direct, but with nearly 1500 mathematical formulae, this reference work primarily appeals to the community of mathematically-schooled researchers, although anyone lecturing or teaching in celestial mechanics will see this jewel as a treasure trove to be visited on.

Systems Theory and the Earth Systems Approach in Science Education. ERIC Digest.

ERIC Educational Resources Information Center

Lee, Hyongyong

The systems approach provides a framework for integrating different scientific disciplines. This approach is used often in Earth Systems Education. This ERIC Digest describes the systems theory and its influence on science education. (Contains 16 references.) (YDS)

Earth's earliest biosphere-a proposal to develop a collection of curated archean geologic reference materials

NASA Technical Reports Server (NTRS)

Lindsay, John F.; McKay, David S.; Allen, Carlton C.

2003-01-01

The discovery of evidence indicative of life in a Martian meteorite has led to an increase in interest in astrobiology. As a result of this discovery, and the ensuing controversy, it has become apparent that our knowledge of the early development of life on Earth is limited. Archean stratigraphic successions containing evidence of Earth's early biosphere are well preserved in the Pilbara Craton of Western Australia. The craton includes part of a protocontinent consisting of granitoid complexes that were emplaced into, and overlain by, a 3.51-2.94 Ga volcanigenic carapace - the Pilbara Supergroup. The craton is overlain by younger supracrustal basins that form a time series recording Earth history from approximately 2.8 Ga to approximately 1.9 Ga. It is proposed that a well-documented suite of these ancient rocks be collected as reference material for Archean and astrobiological research. All samples would be collected in a well-defined geological context in order to build a framework to test models for the early evolution of life on Earth and to develop protocols for the search for life on other planets.

Atmospheric heat engines on earth and Mars

NASA Astrophysics Data System (ADS)

Philip, J. R.

1987-06-01

The character of the earth's atmospheric heat engine depends, inter alia, on the relatively tight linkage between surface fluxes of energy and of H2O. On Mars, on the other hand, H2O-based latent heat fluxes are only a trivial fraction of total surface energy fluxes, and the dominant component of the working fluid is CO2. These considerations are made quantitative through evaluation of Lambda, the equivalent temperature excess at the surface for a particular component of the working fluid. The very different values (and latitudinal distribution) of Lambda on the two planets signalize vividly their different meteorology. Preliminary study of the climatology of Lambda on earth brings out, in particular, the tightness of the H2O-energy linkage in the tropics.

Acetylene fuel from atmospheric CO2 on Mars

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.; Linne, Diane L.

1992-01-01

The Mars mission scenario proposed by Baker and Zubrin (1990) intended for an unmanned preliminary mission is extended to maximize the total impulse of fuel produced with a minimum mass of hydrogen from Earth. The hydrogen along with atmospheric carbon dioxide is processed into methane and oxygen by the exothermic reaction in an atmospheric processing module. Use of simple chemical reactions to produce acetylene/oxygen rocket fuel on Mars from hydrogen makes it possible to produce an amount of fuel that is nearly 100 times the mass of hydrogen brought from earth. If such a process produces the return propellant for a manned Mars mission, the required mission mass in LEO is significantly reduced over a system using all earth-derived propellants.

LEOrbit: A program to calculate parameters relevant to modeling Low Earth Orbit spacecraft-plasma interaction

NASA Astrophysics Data System (ADS)

Marchand, R.; Purschke, D.; Samson, J.

2013-03-01

Understanding the physics of interaction between satellites and the space environment is essential in planning and exploiting space missions. Several computer models have been developed over the years to study this interaction. In all cases, simulations are carried out in the reference frame of the spacecraft and effects such as charging, the formation of electrostatic sheaths and wakes are calculated for given conditions of the space environment. In this paper we present a program used to compute magnetic fields and a number of space plasma and space environment parameters relevant to Low Earth Orbits (LEO) spacecraft-plasma interaction modeling. Magnetic fields are obtained from the International Geophysical Reference Field (IGRF) and plasma parameters are obtained from the International Reference Ionosphere (IRI) model. All parameters are computed in the spacecraft frame of reference as a function of its six Keplerian elements. They are presented in a format that can be used directly in most spacecraft-plasma interaction models. Catalogue identifier: AENY_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENY_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 270308 No. of bytes in distributed program, including test data, etc.: 2323222 Distribution format: tar.gz Programming language: FORTRAN 90. Computer: Non specific. Operating system: Non specific. RAM: 7.1 MB Classification: 19, 4.14. External routines: IRI, IGRF (included in the package). Nature of problem: Compute magnetic field components, direction of the sun, sun visibility factor and approximate plasma parameters in the reference frame of a Low Earth Orbit satellite. Solution method: Orbit integration, calls to IGRF and IRI libraries and transformation of coordinates from geocentric to spacecraft frame reference. Restrictions: Low Earth orbits, altitudes between 150 and 2000 km. Running time: Approximately two seconds to parameterize a full orbit with 1000 points.

Earth Global Reference Atmospheric Model (GRAM99): Short Course

NASA Technical Reports Server (NTRS)

Leslie, Fred W.; Justus, C. G.

2007-01-01

Earth-GRAM is a FORTRAN software package that can run on a variety of platforms including PC's. For any time and location in the Earth's atmosphere, Earth-GRAM provides values of atmospheric quantities such as temperature, pressure, density, winds, constituents, etc.. Dispersions (perturbations) of these parameters are also provided and have realistic correlations, means, and variances - useful for Monte Carlo analysis. Earth-GRAM is driven by observations including a tropospheric database available from the National Climatic Data Center. Although Earth-GRAM can be run in a "stand-alone" mode, many users incorporate it into their trajectory codes. The source code is distributed free-of-charge to eligible recipients.

Reference earth orbital research and applications investigations (blue book). Volume 4: Earth observations

NASA Technical Reports Server (NTRS)

1971-01-01

The earth observations capability of the space station and space shuttle program definition is discussed. The stress in the functional program element has been to update the sensor specifications and to shift some of the emphasis from sensors to experiments to be done aboard the facility. The earth observations facility will include provisions for data acquisition, sensor control and display, data analysis, and maintenance and repair. The facility is research and development in nature with a potential for operational applications.

Method for preparing high cure temperature rare earth iron compound magnetic material

DOEpatents

Huang, Yuhong; Wei, Qiang; Zheng, Haixing

2002-01-01

Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.

DAsHER CD: Developing a Data-Oriented Human-Centric Enterprise Architecture for EarthCube

NASA Astrophysics Data System (ADS)

Yang, C. P.; Yu, M.; Sun, M.; Qin, H.; Robinson, E.

2015-12-01

One of the biggest challenges that face Earth scientists is the resource discovery, access, and sharing in a desired fashion. EarthCube is targeted to enable geoscientists to address the challenges by fostering community-governed efforts that develop a common cyberinfrastructure for the purpose of collecting, accessing, analyzing, sharing and visualizing all forms of data and related resources, through the use of advanced technological and computational capabilities. Here we design an Enterprise Architecture (EA) for EarthCube to facilitate the knowledge management, communication and human collaboration in pursuit of the unprecedented data sharing across the geosciences. The design results will provide EarthCube a reference framework for developing geoscience cyberinfrastructure collaborated by different stakeholders, and identifying topics which should invoke high interest in the community. The development of this EarthCube EA framework leverages popular frameworks, such as Zachman, Gartner, DoDAF, and FEAF. The science driver of this design is the needs from EarthCube community, including the analyzed user requirements from EarthCube End User Workshop reports and EarthCube working group roadmaps, and feedbacks or comments from scientists obtained by organizing workshops. The final product of this Enterprise Architecture is a four-volume reference document: 1) Volume one is this document and comprises an executive summary of the EarthCube architecture, serving as an overview in the initial phases of architecture development; 2) Volume two is the major body of the design product. It outlines all the architectural design components or viewpoints; 3) Volume three provides taxonomy of the EarthCube enterprise augmented with semantics relations; 4) Volume four describes an example of utilizing this architecture for a geoscience project.

Optimizing Societal Benefit using a Systems Engineering Approach for Implementation of the GEOSS Space Segment

NASA Technical Reports Server (NTRS)

Killough, Brian D., Jr.; Sandford, Stephen P.; Cecil, L DeWayne; Stover, Shelley; Keith, Kim

2008-01-01

The Group on Earth Observations (GEO) is driving a paradigm shift in the Earth Observation community, refocusing Earth observing systems on GEO Societal Benefit Areas (SBA). Over the short history of space-based Earth observing systems most decisions have been made based on improving our scientific understanding of the Earth with the implicit assumption that this would serve society well in the long run. The space agencies responsible for developing the satellites used for global Earth observations are typically science driven. The innovation of GEO is the call for investments by space agencies to be driven by global societal needs. This paper presents the preliminary findings of an analysis focused on the observational requirements of the GEO Energy SBA. The analysis was performed by the Committee on Earth Observation Satellites (CEOS) Systems Engineering Office (SEO) which is responsible for facilitating the development of implementation plans that have the maximum potential for success while optimizing the benefit to society. The analysis utilizes a new taxonomy for organizing requirements, assesses the current gaps in spacebased measurements and missions, assesses the impact of the current and planned space-based missions, and presents a set of recommendations.

Preliminary investigations of protein crystal growth using the Space Shuttle

NASA Technical Reports Server (NTRS)

Delucas, L. J.; Suddath, F. L.; Snyder, R.; Naumann, R.; Broom, M. B.; Pusey, M.; Yost, V.; Herren, B .; Carter, D.

1986-01-01

Four preliminary Shuttle experiments are described which have been used to develop prototype hardware for a more advanced system that will evaluate effects of gravity on protein crystal growth. The first phase of these experiments has centered on the development of micromethods for protein crystal growth by vapor-diffusion techniques (using a space version of the hanging-drop method) and on dialysis using microdialysis cells. Results suggest that the elimination of density-driven sedimentation can effect crystal morphology. In the dialysis experiment, space-grown crystals of concanavalin B were three times longer and 1/3 the thickness of earth-grown crystals.

A preliminary estimate of the EUVE cumulative distribution of exposure time on the unit sphere. [Extreme Ultra-Violet Explorer

NASA Technical Reports Server (NTRS)

Tang, C. C. H.

1984-01-01

A preliminary study of an all-sky coverage of the EUVE mission is given. Algorithms are provided to compute the exposure of the celestial sphere under the spinning telescopes, taking into account that during part of the exposure time the telescopes are blocked by the earth. The algorithms are used to give an estimate of exposure time at different ecliptic latitudes as a function of the angle of field of view of the telescope. Sample coverage patterns are also given for a 6-month mission.

Preliminary study of superconducting bulk magnets for Maglev

NASA Astrophysics Data System (ADS)

Fujimoto, Hiroyuki; Kamijo, Hiroki

Recent development shows that melt-processed YBaCuO (Y123) or Rare Earth (RE)123 superconductors have a high Jc at 77 K and high magnetic field, leading to high field application as a superconducting quasi-permanent bulk magnet with the liquid nitrogen refrigeration. One of the promising applications is a superconducting magnet for the magnetically levitated (Maglev) train. We discuss a superconducting bulk magnet for the Maglev train in the aspect of a preliminary design of the bulk magnet and also processing for (L)REBaCuO bulk superconductors and their characteristic superconducting properties.

Preliminary comparative assessment of PM10 hourly measurement results from new monitoring stations type using stochastic and exploratory methodology and models

NASA Astrophysics Data System (ADS)

Czechowski, Piotr Oskar; Owczarek, Tomasz; Badyda, Artur; Majewski, Grzegorz; Rogulski, Mariusz; Ogrodnik, Paweł

2018-01-01

The paper presents selected preliminary stage key issues proposed extended equivalence measurement results assessment for new portable devices - the comparability PM10 concentration results hourly series with reference station measurement results with statistical methods. In article presented new portable meters technical aspects. The emphasis was placed on the comparability the results using the stochastic and exploratory methods methodology concept. The concept is based on notice that results series simple comparability in the time domain is insufficient. The comparison of regularity should be done in three complementary fields of statistical modeling: time, frequency and space. The proposal is based on model's results of five annual series measurement results new mobile devices and WIOS (Provincial Environmental Protection Inspectorate) reference station located in Nowy Sacz city. The obtained results indicate both the comparison methodology completeness and the high correspondence obtained new measurements results devices with reference.

75 FR 16833 - Preliminary Revised 5-Year Outer Continental Shelf (OCS) Oil and Gas Leasing Program for 2007-2012

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

... Continental Shelf (OCS) Oil and Gas Leasing Program for 2007-2012 AGENCY: Minerals Management Service... (MMS) requests comments on the Preliminary Revised 5-Year OCS Oil and Gas Leasing Program for 2007... Elden Street, MS-4010; Herndon, Virginia 20170-4817. Please reference ``Remand of the 2007-2012 OCS Oil...

On-Orbit Gradiometry with the scientific instrument of the French Space Mission MICROSCOPE

NASA Astrophysics Data System (ADS)

Foulon, B.; Baghi, Q.; Panet, I.; Rodrigues, M.; Metris, G.; Touboul, P.

2017-12-01

The MICROSCOPE mission is fully dedicated to the in-orbit test of the universality of free fall, the so-called Weak Equivalence Principle (WEP). Based on a CNES Myriade microsatellite launched on the 25th of April 2016, MICROSCOPE is a CNES-ESA-ONERA-CNRS-OCA mission, the scientific objective of which is to test of the Equivalence Principle with an extraordinary accuracy at the level of 10-15. The measurement will be obtained from the T-SAGE (Twin Space Accelerometer for Gravitational Experimentation) instrument constituted by two ultrasensitive differential accelerometers. One differential electrostatic accelerometer, labeled SU-EP, contains, at its center, two proof masses made of Titanium and Platinum and is used for the test. The twin accelerometer, labeled SU-REF, contains two Platinum proof masses and is used as a reference instrument. Separated by a 17 cm-length arm, they are embarked in a very stable and soft environment on board a satellite equipped with a drag-free control system and orbiting on a sun synchronous circular orbit at 710 km above the Earth. In addition to the WEP test, this configuration can be interesting for various applications, and one of the proposed ideas is to use MICROSCOPE data for the measurement of Earth's gravitational gradient. Considering the gradiometer formed by the inner Platinum proof-masses of the two differential accelerometers and the arm along the Y-axis of the instrument which is perpendicular to the orbital plane, possibly 3 components of the gradient can be measured: Txy, Tyy and Tzy. Preliminary studies suggest that the errors can be lower than 10mE. Taking advantage of its higher altitude with respect to GOCE, the low frequency signature of Earth's potential seen by MICROSCOPE could provide an additional observable in gradiometry to discriminate between different models describing the large scales of the mass distribution in the Earth's deep mantle. The poster will shortly present the MICROSCOPE mission configuration. It will detail the actual in-flight performances of the accelerometers and of the attitude and position control, in order to evaluate the gradiometer error budget according to the satellite pointing mode configuration.

NASA's Earth Science Enterprise: 1998 Education Catalog

NASA Technical Reports Server (NTRS)

1998-01-01

This catalog presents a reference guide to NASA Earth science education programs and products. The topics include: 1) Student Support (Elementary and Secondary, Undergraduate and Graduate, Postgraduate, and Postdoctorate); 2) Teacher/Faculty Preparation and Enhancement; 3) Systemic Change; 4) Curriculum Support; and 5) Resources.

An Analysis of Earth Science Data Analytics Use Cases

NASA Technical Reports Server (NTRS)

Shie, Chung-Lin; Kempler, Steve

2014-01-01

The increase in the number and volume, and sources, of globally available Earth science data measurements and datasets have afforded Earth scientists and applications researchers unprecedented opportunities to study our Earth in ever more sophisticated ways. In fact, the NASA Earth Observing System Data Information System (EOSDIS) archives have doubled from 2007 to 2014, to 9.1 PB (Ramapriyan, 2009; and https:earthdata.nasa.govaboutsystem-- performance). In addition, other US agency, international programs, field experiments, ground stations, and citizen scientists provide a plethora of additional sources for studying Earth. Co--analyzing huge amounts of heterogeneous data to glean out unobvious information is a daunting task. Earth science data analytics (ESDA) is the process of examining large amounts of data of a variety of types to uncover hidden patterns, unknown correlations and other useful information. It can include Data Preparation, Data Reduction, and Data Analysis. Through work associated with the Earth Science Information Partners (ESIP) Federation, a collection of Earth science data analytics use cases have been collected and analyzed for the purpose of extracting the types of Earth science data analytics employed, and requirements for data analytics tools and techniques yet to be implemented, based on use case needs. ESIP generated use case template, ESDA use cases, use case types, and preliminary use case analysis (this is a work in progress) will be presented.

Spin State of Returning Fly-by Near Earth Asteroid 2012 TC4

NASA Astrophysics Data System (ADS)

Ryan, William; Ryan, Eileen V.

2017-10-01

The ten-meter class near-Earth asteroid 2012 TC4 will make a close approach to the Earth on October 12, 2017. As of July 2017, the close approach distance ranges from 0.003 to 0.64 lunar distances (LD) with a nominal value of 0.23 LD. However this is the second observable close approach that this object has made since its discovery. In particular, broadband photometry was obtained for 2012 TC4 on 10 and 11 October 2012 using the Magdalena Ridge Observatory (MRO) 2.4-meter telescope. A periodicity of ~12.2 minutes was immediately evident in the time-series data, which was in agreement with the reported values of Polishook (2013), Odden et al. (2012), Warner (2013), and Carbognani (2014). The lightcurve displays an amplitude of ~0.9 magnitude, which implies that it is highly elongated with an axial ratio of a/b>2.3. However, a second period is also clearly evident in the MRO data, indicating that the asteroid is in a state of non-principle axis rotation.The nature of its orbit has made 2012 TC4 an attractive Earth-impacting asteroid surrogate for an exercise testing the capabilities of the scientific and emergency response communities (Reddy, 2017). For this reason, it is anticipated that considerable resources, including MRO, will be utilized to take advantage of the 2017 flyby to study this asteroid. Here, we present the details of the tumbling nature of this fast-spinning object observed during the October 2012 discovery apparition. These data were acquired before closest approach in 2012 where the asteroid came within 0.25 lunar distances of Earth. Therefore, this analysis will be discussed in the context of the spin state observations planned for early October 2017 at MRO, for which preliminary results will also be reported. In particular, comparison of the observed rotation state from the two apparitions can be indicative of any effects of Earth’s gravity during the 2012 flyby.References:Odden, C.E., Verhaegh, J.C., McCullough, D.G., and Briggs, J.W. (2013). Minor Planet Bul. 40, 176-177.Warner, B.D. (2013). Minor Planet Bul. 40, 71-80.Polishook, D. (2013). Minor Planet Bul. 40, 42-43.Carbognani, A. (2014). Minor Planet Bul. 41, 4-8.Reddy, V. (2017), AMOS SSA Technical Conference, Maui, HI.

Measuring the Carolina Bays Using Archetype Template Overlays on the Google Earth Virtual Globe; Planform Metrics for 25,000 Bays Extracted from LiDAR and Satellite Imagery

NASA Astrophysics Data System (ADS)

Davias, M. E.; Gilbride, J. L.

2011-12-01

Aerial photographs of Carolina bays taken in the 1930's sparked the initial research into their geomorphology. Satellite Imagery available today through the Google Earth Virtual Globe facility expands the regions available for interrogation, but reveal only part of their unique planforms. Digital Elevation Maps (DEMs), using Light Detection And Ranging (LiDAR) remote sensing data, accentuate the visual presentation of these aligned ovoid shallow basins by emphasizing their robust circumpheral rims. To support a geospatial survey of Carolina bay landforms in the continental USA, 400,000 km2 of hsv-shaded DEMs were created as KML-JPEG tile sets. A majority of these DEMs were generated with LiDAR-derived data. We demonstrate the tile generation process and their integration into Google Earth, where the DEMs augment available photographic imagery for the visualization of bay planforms. While the generic Carolina bay planform is considered oval, we document subtle regional variations. Using a small set of empirically derived planform shapes, we created corresponding Google Earth overlay templates. We demonstrate the analysis of an individual Carolina bay by placing an appropriate overlay onto the virtually globe, then orientating, sizing and rotating it by edit handles such that it satisfactorily represents the bay's rim. The resulting overlay data element is extracted from Google Earth's object directory and programmatically processed to generate metrics such as geographic location, elevation, major and minor axis and inferred orientation. Utilizing a virtual globe facility for data capture may result in higher quality data compared to methods that reference flat maps, where geospatial shape and orientation of the bays could be skewed and distorted in the orthographic projection process. Using the methodology described, we have measured over 25k distinct Carolina bays. We discuss the Google Fusion geospatial data repository facility, through which these data have been assembled and made web-accessible to other researchers. Preliminary findings from the survey are discussed, such as how bay surface area, eccentricity and orientation vary across ~800 1/4° × 1/4° grid elements. Future work includes measuring 25k additional bays, as well as interrogation of the orientation data to identify any possible systematic geospatial relationships.

75 FR 53961 - Pajuela Peak Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

... hydraulic head of 1,465 feet; (2) a proposed 50-ft zoned earth and rockfill lower dam with a 5,896-ft length... 150 MW and two 50 MW reversible pump/turbine generating units having an installed capacity of 250...

Solaris: Orbital station: Automatic laboratory for outer space rendezvous and operations

NASA Technical Reports Server (NTRS)

Runavot, J. J.

1981-01-01

The preliminary design for a modular orbital space station (unmanned) is outlined. The three main components are a support module, an experiment module, and an orbital transport vehicle. The major types of missions (assembly, materials processing, and Earth observation) that could be performed are discussed.

ALSEP arrays A, B, C, and A-2. [lunar surface exploration instrument specifications

NASA Technical Reports Server (NTRS)

1973-01-01

The objectives of the lunar surface exploration packages are defined and the preliminary design of scientific systems hardware is reported. Instrument packages are to collect and transmit to earth scientific data on the lunar interior, the lunar surface composition, and the lunar geomorphology

Laplacean Ideology for Preliminary Orbit Determination and Moving Celestial Body Identification in Virtual Epoch

NASA Astrophysics Data System (ADS)

Bykov, O. P.

Any CCD frames with stars or galaxies or clusters and other images must be studied for a searching of moving celestial objects, namely asteroids, comets, artificial Earth satellites inside them. At Pulkovo Astronomical Observatory, new methods and software were elaborated to solve this problem.

Concept development of automatic guidance for rotorcraft obstacle avoidance

NASA Technical Reports Server (NTRS)

Cheng, Victor H. L.

1990-01-01

The automatic guidance of rotorcraft for obstacle avoidance in nap-of-the-earth flight is studied. A hierarchical breakdown of the guidance components is used to identify the functional requirements. These requirements and anticipated sensor capabilities lead to a preliminary guidance concept, which has been evaluated via computer simulations.

Determination of Galactic Aberration from VLBI Measurements and Its Effect on VLBI Reference Frames and Earth Orientation Parameters.

NASA Astrophysics Data System (ADS)

MacMillan, D. S.

2014-12-01

Galactic aberration is due to the motion of the solar system barycenter around the galactic center. It results in a systematic pattern of apparent proper motion of radio sources observed by VLBI. This effect is not currently included in VLBI analysis. Estimates of the size of this effect indicate that it is important that this secular aberration drift be accounted for in order to maintain an accurate celestial reference frame and allow astrometry at the several microarcsecond level. Future geodetic observing systems are being designed to be capable of producing a future terrestrial reference frame with an accuracy of 1 mm and stability of 0.1 mm/year. We evaluate the effect galactic aberration on attaining these reference frame goals. This presentation will discuss 1) the estimation of galactic aberration from VLBI data and 2) the effect of aberration on the Terrestrial and Celestial Reference Frames and the Earth Orientation Parameters that connect these frames.

Localization Strategies in WSNs as applied to Landslide Monitoring (Invited)

NASA Astrophysics Data System (ADS)

Massa, A.; Robol, F.; Polo, A.; Giarola, E.; Viani, F.

2013-12-01

In the last years, heterogeneous integrated smart systems based on wireless sensor network (WSN) technology have been developed at the ELEDIA Research Center of the University of Trento [1]. One of the key features of WSNs as applied to distributed monitoring is that, while the capabilities of each single sensor node is limited, the implementation of cooperative schemes throughout the whole network enables the solution of even complex tasks, as the landslide monitoring. The capability of localizing targets respect to the position of the sensor nodes turns out to be fundamental in those application fields where relative movements arise. The main properties like the target typology, the movement characteristics, and the required localization resolution are different changing the reference scenario. However, the common key issue is still the localization of moving targets within the area covered by the sensor network. Many experiences were preparatory for the challenging activities in the field of landslide monitoring where the basic idea is mostly that of detecting slight soil movements. Among them, some examples of WSN-based systems experimentally applied to the localization of people [2] and wildlife [3] have been proposed. More recently, the WSN backbone as well as the investigated sensing technologies have been customized for monitoring superficial movements of the soil. The relative positions of wireless sensor nodes deployed where high probability of landslide exists is carefully monitored to forecast dangerous events. Multiple sensors like ultrasound, laser, high precision GPS, for the precise measurement of relative distances between the nodes of the network and the absolute positions respect to reference targets have been integrated in a prototype system. The millimeter accuracy in the position estimation enables the detection of small soil modifications and to infer the superficial evolution profile of the landslide. This information locally acquired also represent a fine tuning of large scale satellite acquisitions, usually adopted for remote sensing of landslides. The integration of dense and frequent WSN data within satellite image analysis will enhance the sensing capabilities leading to a multi-resolution and an highly space-time calibrated system. The WSN-based system has been preliminary tested in controlled environments in the ELEDIA laboratories and is now installed in a real test site where an active landslide is evolving. Preliminary data are here presented to assess the feasibility of the investigated solution in landslide monitoring and event forecasting. REFERENCES [1] M. Benedetti, L. Ioriatti, M. Martinelli, and F. Viani, 'Wireless sensor network: a pervasive technology for earth observation,' in IEEE Journal of Selected Topics in App. Earth Obs. And Remote Sens., vol. 3, no. 4, pp. 488-497, 2010. [2] F. Viani, M. Donelli, P. Rocca, G. Oliveri, D. Trinchero, and A. Massa, 'Localization, tracking and imaging of targets in wireless sensor networks,' Radio Science, vol. 46, no. 5, 2011. [3] F. Viani, F. Robol, M. Salucci, E. Giarola, S. De Vigili, M. Rocca, F. Boldrini, G. Benedetti, and A. Massa, 'WSN-based early alert system for preventing wildlife-vehicle collisions in Alps regions - From the laboratory test to the real-world implementation,' 7th European Conference on Antennas and Propagation 2013 (EUCAP2013), Gothenburg, Sweden, April 8-12, 2013.

Preliminary Axial Flow Turbine Design and Off-Design Performance Analysis Methods for Rotary Wing Aircraft Engines. Part 1; Validation

NASA Technical Reports Server (NTRS)

Chen, Shu-cheng, S.

2009-01-01

For the preliminary design and the off-design performance analysis of axial flow turbines, a pair of intermediate level-of-fidelity computer codes, TD2-2 (design; reference 1) and AXOD (off-design; reference 2), are being evaluated for use in turbine design and performance prediction of the modern high performance aircraft engines. TD2-2 employs a streamline curvature method for design, while AXOD approaches the flow analysis with an equal radius-height domain decomposition strategy. Both methods resolve only the flows in the annulus region while modeling the impact introduced by the blade rows. The mathematical formulations and derivations involved in both methods are documented in references 3, 4 for TD2-2) and in reference 5 (for AXOD). The focus of this paper is to discuss the fundamental issues of applicability and compatibility of the two codes as a pair of companion pieces, to perform preliminary design and off-design analysis for modern aircraft engine turbines. Two validation cases for the design and the off-design prediction using TD2-2 and AXOD conducted on two existing high efficiency turbines, developed and tested in the NASA/GE Energy Efficient Engine (GE-E3) Program, the High Pressure Turbine (HPT; two stages, air cooled) and the Low Pressure Turbine (LPT; five stages, un-cooled), are provided in support of the analysis and discussion presented in this paper.

Professionality of Junior High School (SMP) Science Teacher in Preparing Instructional Design of Earth and Space Sciences (IPBA)

NASA Astrophysics Data System (ADS)

Marlina, L.; Liliasari; Tjasyono, B.; Hendayana, S.

2017-02-01

The teacher is one important factor in the provision of education in schools. Therefore, improving the quality of education means we need to enhance the quality and the professionalism of teachers. We offer a solution through education and training of junior high school science teachers in developing the instructional design of Earth and Space Sciences (IPBA). IPBA is part of the science subjects which is given to students from elementary school to college. This research is a preliminary study of junior high school science teacher professionalism in creating instructional design IPBA. Mixed method design is used to design the research. Preliminary studies conducted on junior high school science teacher in one MGMPs in South Sumatera, and the respondent are 18 teachers from 13 schools. The educational background of science teachers who teach IPBA not only from physical education but also biology and agriculture. The result of preliminary study showed that the ratio of teachers who teach IPBA are 56% from physic education, 39% from biology, and 5% from agriculture. The subjects of IPBA that considered difficult by teachers are the distribution of sun, moon, and satellite motion; specific processes in lithosphere and atmosphere; and the correlation between lithosphere and atmosphere with the environment. The teachers also face difficulty in preparing media, choosing the right methods in teaching IPBA.

Geological Mapping of Fortuna Tessera (V-2): Venus and Earth's Archean Process Comparisons

NASA Technical Reports Server (NTRS)

Head, James W.; Hurwitz,D. M.; Ivanov, M. A.; Basilevsky, A. T.; Kumar, P. Senthil

2008-01-01

The geological features, structures, thermal conditions, interpreted processes, and outstanding questions related to both the Earth's Archean and Venus share many similarities and we are using a problem-oriented approach to Venus mapping, guided by insight from the Archean record of the Earth, to gain new insight into the evolution of Venus and Earth's Archean. The Earth's preserved and well-documented Archean record provides important insight into high heat-flux tectonic and magmatic environments and structures and the surface of Venus reveals the current configuration and recent geological record of analogous high-temperature environments unmodified by subsequent several billion years of segmentation and overprinting, as on Earth. Elsewhere we have addressed the nature of the Earth's Archean, the similarities to and differences from Venus, and the specific Venus and Earth-Archean problems on which progress might be made through comparison. Here we present the major goals of the Venus-Archean comparison and show how preliminary mapping of the geology of the V-2 Fortuna Tessera quadrangle is providing insight on these problems. We have identified five key themes and questions common to both the Archean and Venus, the assessment of which could provide important new insights into the history and processes of both planets.

Looking for Fossil Bacteria in Martian Materials

NASA Technical Reports Server (NTRS)

Westall, F.; Walsh, M. M.; Mckay, D. D.; Wentworth, S.; Gibson, E. K.; Steele, A.; Toporski, J.; Lindstrom, D.; Martinez, R.; Allen, C. C.

1999-01-01

The rationale for looking for prokaryote fossils in Martian materials is based on our present understanding of the environmental evolution of that planet in comparison to the history of the terrestrial environments and the development and evolution of life on Earth. On Earth we have clear, albeit indirect, evidence of life in 3.8 b.y.-old rocks from Greenland and the first morphological fossils in 3.3-3.5 b.y.-old cherts from South Africa and Australia. In comparison, Mars, being smaller, probably cooled down after initial aggregation faster than the Earth. Consequently, there could have been liquid water on its surface earlier than on Earth. With a similar exogenous and endogenous input of organics and life-sustaining nutrients as is proposed for the Earth, life could have arisen on that planet, possibly slightly earlier dm it did on Earth. Whereas on Earth liquid water has remained at the surface of the planet since about 4.4 b.y. (with some possible interregnums caused by planet-sterilising impacts before 3.8. b.y. and perhaps a number of periods of a totally frozen Earth, this was not the case with Mars. Although it is not known exactly when surficial water disappeared from the surface, there would have been sufficient time for life to have developed into something similar to the terrestrial prokaryote stage. However, given the earlier environmental deterioration, it is unlikely that it evolved into the eukaryote stage and even evolution of oxygenic photosynthesis may not have been reached. Thus, the impetus of research is on single celled life simnilar to prokaryotes. We are investigating a number of methods of trace element analysis with respect to the Early Archaean microbial fossils. Preliminary neutron activation analysis of carbonaceous layers in the Early Archaean cherts from South Africa and Australia shows some partitioning of elements such as As, Sb, Cr with an especial enrichment of lanthanides in a carbonaceous-rich banded iron sediment . More significantly, preliminary TOF-SIMS investigations of organics in the cherts reveals the presence of a biomarker, which appears to be a derivative of bacterial polymer, in the carbonaceous parts of the rocks. We conclude that a combination of morphological, isotope and biogeochemical methods can be used to successfully identify signs of life in terrestrial material, and that these methods will be useful in searching for signs of life in extraterrestrial materials.

Terrestrial analogs to Mars

NASA Technical Reports Server (NTRS)

Farr, T. G.; Arcone, S.; Arvidson, R.; Baker, V.; Barlow, N.; Beaty, D.; Bell, M.; Blankenship, D.; Bridges, N.; Briggs, G.;

Chapter F: Preliminary Bibliography of Lacustrine Diatomite Deposits in the Western United States and Related Topics

USGS Publications Warehouse

Bolm, Karen S.; Wallace, Alan R.; Moyle, Phillip R.; Bliss, James D.; Orris, Greta J.

2003-01-01

Introduction As part of the assessment of lacustrine diatomite resources in the Western United States (fig. 1), U.S. Geological Survey (USGS) project members conducted a review of literature relating to the formation, location, and nature of deposits in the study area. This preliminary bibliography consists of selected publications to identify, locate, and describe the deposits to be studied, to characterize common geologic factors about the deposits, and to better understand the factors that control their formation, preservation, or destruction. The bibliography also serves as a resource for other workers to research the topic. References included in the preliminary bibliography were gathered by searching existing bibliographic data bases and library collections. Project researchers also contributed references that they found during the course of their work. This bibliography should be considered a working document that will grow as research and literature searches continue. Clearly, many significant publications may be missing from this preliminary list; therefore, USGS staff members intend to issue a revised bibliography as project work progresses. To assure completeness, input from other researchers and industry is welcome. Although the focus of this bibliography is lacustrine diatomite deposits of the Western United States, additional references that provide a foundation of knowledge for the study of diatomites, diatoms, and diatom-related processes (ecology, geology, geochemistry) and for the uses and behavior of diatomite have also been included. An index of keywords has been added to this bibliography, designed to help the user locate reports by topic or by geographic location. The letter 'A' following a number indicates that the report referenced is an abstract.

Earth Observations taken by the STS-135 Crew

NASA Image and Video Library

2011-07-09

S135-E-006268 (9 July 2011) --- A nadir view from the Earth-orbiting space shuttle Atlantis, photographed by one of four STS-135 crewmembers, shows the area of Italy referred to as the "boot." Part of Sicily is at frame's bottom center. The astronauts were on the mission's second day of activity in Earth orbit, and the eve of docking day with the International Space Station. Photo credit: NASA

The physics of the earth's core: An introduction

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

Melchior, P.

1986-01-01

This book is a reference text providing information on physical topics of recent developments in internal geophysics. The text summarizes papers covering theoretical geophysics. Basic formulae, definitions and theorems are not explained in detail due to the limited space. The contents include applications to geodesy, geophysics, astronomy, astrophysics, geophysics and planetary physics. The formal contents include: The Earth's model; Thermodynamics; Hydrodynamics; Geomagnetism; Geophysical implications in the Earth's core.

Non-linearity of geocentre motion and its impact on the origin of the terrestrial reference frame

NASA Astrophysics Data System (ADS)

Dong, Danan; Qu, Weijing; Fang, Peng; Peng, Dongju

2014-08-01

The terrestrial reference frame is a cornerstone for modern geodesy and its applications for a wide range of Earth sciences. The underlying assumption for establishing a terrestrial reference frame is that the motion of the solid Earth's figure centre relative to the mass centre of the Earth system on a multidecadal timescale is linear. However, past international terrestrial reference frames (ITRFs) showed unexpected accelerated motion in their translation parameters. Based on this underlying assumption, the inconsistency of relative origin motions of the ITRFs has been attributed to data reduction imperfection. We investigated the impact of surface mass loading from atmosphere, ocean, snow, soil moisture, ice sheet, glacier and sea level from 1983 to 2008 on the geocentre variations. The resultant geocentre time-series display notable trend acceleration from 1998 onward, in particular in the z-component. This effect is primarily driven by the hydrological mass redistribution in the continents (soil moisture, snow, ice sheet and glacier). The acceleration is statistically significant at the 99 per cent confidence level as determined using the Mann-Kendall test, and it is highly correlated with the satellite laser ranging determined translation series. Our study, based on independent geophysical and hydrological models, demonstrates that, in addition to systematic errors from analysis procedures, the observed non-linearity of the Earth-system behaviour at interannual timescales is physically driven and is able to explain 42 per cent of the disparity between the origins of ITRF2000 and ITRF2005, as well as the high level of consistency between the ITRF2005 and ITRF2008 origins.

Evolution of Orion Mission Design for Exploration Mission 1 and 2

NASA Technical Reports Server (NTRS)

Gutkowski, Jeffrey P.; Dawn, Timothy F.; Jedrey, Richard M.

2016-01-01

The evolving mission design and concepts of NASA’s next steps have shaped Orion into the spacecraft that it is today. Since the initial inception of Orion, through the Constellation Program, and now in the Exploration Mission frame-work with the Space Launch System (SLS), each mission design concept and pro-gram goal have left Orion with a set of capabilities that can be utilized in many different mission types. Exploration Missions 1 and 2 (EM-1 and EM-2) have now been at the forefront of the mission design focus for the last several years. During that time, different Design Reference Missions (DRMs) were built, analyzed, and modified to solve or mitigate enterprise level design trades to ensure a viable mission from launch to landing. The resulting DRMs for EM-1 and EM-2 were then expanded into multi-year trajectory scans to characterize vehicle performance as affected by variations in Earth-Moon geometry. This provides Orion’s subsystems with stressing reference trajectories to help design their system. Now that Orion has progressed through the Preliminary and Critical Design Reviews (PDR and CDR), there is a general shift in the focus of mission design from aiding the vehicle design to providing mission specific products needed for pre-flight and real time operations. Some of the mission specific products needed include, large quantities of nominal trajectories for multiple monthly launch periods and abort options at any point in the mission for each valid trajectory in the launch window.

A strongly negative shear velocity gradient and lateral variability in the lowermost mantle beneath the Pacific

NASA Astrophysics Data System (ADS)

Ritsema, Jeroen; Garnero, Edward; Lay, Thorne

1997-01-01

A new approach for constraining the seismic shear velocity structure above the core-mantle boundary is introduced, whereby SH-SKS differential travel times, amplitude ratios of SV/SKS, and Sdiff waveshapes are simultaneously modeled. This procedure is applied to the lower mantle beneath the central Pacific using da.ta from numerous deep-focus southwest Pacific earthquakes recorded in North America. We analyze 90 broadband and 248 digitized analog recordings for this source-receiver geometry. SH-SKS times are highly variable and up to 10 s larger than standard reference model predictions, indicating the presence of laterally varying low shear velocities in the study area. The travel times, however, do not constrain the depth extent or velocity gradient of the low-velocity region. SV/SKS amplitude ratios and SH waveforms are sensitive to the radial shear velocity profile, and when analyzed simultaneously with SH-SKS times, rnveal up to 3% shear velocity reductions restricted to the lowermost 190±50 km of the mantle. Our preferred model for the central-eastern Pacific region (Ml) has a strong negative gradient (with 0.5% reduction in velocity relative to the preliminary reference Earth model (PREM) at 2700 km depth and 3% reduction at 2891 km depth) and slight velocity reductions from 2000 to 2700 km depth (0-0.5% lower than PREM). Significant small-scale (100-500 km) shear velocity heterogeneity (0.5%-1%) is required to explain scatter in the differential times and amplitude ratios.

What do space voyagers value? a thematic analysis of the narratives of spaceflight veterans

NASA Astrophysics Data System (ADS)

Suedfeld, Peter

Values are desired outcomes, differing in importance, that guide people's lives. Considerable anecdotal evidence suggests that astronauts and cosmonauts experience changes in values as a consequence of their experiences in space. Among the most frequently mentioned changes are a greater appreciation of the unity of Earth and humanity, and an increase in self-confidence. Two preliminary studies by the author have confirmed significant changes in values among (a) four Apollo-era American astronauts and (b) ten male astronauts from the Apollo, Mercury, and Gemini programs, three female veterans of the Shuttle-Mir, and two male high-ranking NASA administrators. The current study expanded the database to 104 space veterans from the US, Russia, and other nations, whose narratives (memoirs, media interviews, and oral histories) were subjected to thematic content analysis for references to Schwartz's well-established value categories. Significant pre-flight differences were found related to nationality, space age era (through vs. later than 1975), and longest flight duration. Comparing references from the pre-flight period with those to the time of the mission and then to post-return from space, we found a U-shaped curve for the values of Achievement, Power, and Self-Direction, and steady increases across periods for Enjoyment and Universalism. Compared to multicultural norms, astronauts showed higher values placed on Achievement, Enjoyment (their two primary values), and Power (after the mission only), and lower values on Security, Self-Direction (after the mission), Universalism, and Tradition.

Orientale and South Pole-Aitken basins on the Moon: Preliminary Galileo imaging results

NASA Technical Reports Server (NTRS)

Head, J.; Fischer, E.; Murchie, S.; Pieters, C.; Plutchak, J.; Sunshine, J.; Belton, M.; Carr, M.; Chapman, C.; Davies, M.

1991-01-01

During the Earth-Moon flyby the Galileo Solid State Imaging System obtained new information on the landscape and physical geology of the Moon. Multicolor Galileo images of the Moon reveal variations in color properties of the lunar surface. Using returned lunar samples as a key, the color differences can be interpreted in terms of variations in the mineral makeup of the lunar rocks and soil. The combined results of Apollo landings and multicolor images from Galileo allow extrapolation of surface composition to areas distant from the landing sites, including the far side invisible from Earth.

Onboard Classification of Hyperspectral Data on the Earth Observing One Mission

NASA Technical Reports Server (NTRS)

Chien, Steve; Tran, Daniel; Schaffer, Steve; Rabideau, Gregg; Davies, Ashley Gerard; Doggett, Thomas; Greeley, Ronald; Ip, Felipe; Baker, Victor; Doubleday, Joshua;

Wide area coverage radar imaging satellite for earth applications. [surveillance and mapping of ice on Great Lakes

NASA Technical Reports Server (NTRS)

Stevens, G. H.; Ramler, J. R.

1974-01-01

A preliminary study was made of a radar imaging satellite for earth applications. A side-looking synthetic-aperture radar was considered and the feasibility of obtaining a wide area coverage to reduce the time required to image a given area was investigated. Two basic approaches were examined; low altitude sun-synchronous orbits using a multibeam/multifrequency radar system and equatorial orbits up to near-synchronous altitude using a single beam system. Surveillance and mapping of ice on the Great Lakes was used as a typical application to focus the study effort.

Earth Observatory Satellite system definition study. Report 2: Instrument constraints and interfaces

NASA Technical Reports Server (NTRS)

1974-01-01

The instrument constraints and interface specifications for the Earth Observatory Satellite (EOS) are discussed. The Land Use Classification Mission using a 7 band Thematic Mapper and a 4 band High Resolution Pointable Imager is stressed. The mission and performance of the instruments were reviewed and expanded to reflect the instrument as a part of the total remote sensing system. A preliminary EOS interface handbook is provided to describe the mission and system, to specify the spacecraft interfaces to potential instrument contractors, and to describe the instrument interface data required by the system integration contractor.

Space artificial gravity facilities - An approach to their construction

NASA Technical Reports Server (NTRS)

Wercinski, P. F.; Searby, N. D.; Tillman, B. W.

1988-01-01

In the course of adaptation to a space microgravity environment, humans experience cardiovascular deconditioning, loss of muscle mass, and loss of bone minerals. One possible solution to these space adaptation problems is to simulate earth's gravity using the centripetal acceleration created by a rotating system. The design and construction of rotating space structures pose many challenges. Before committing to the use of artificial gravity in future space missions, a man-rated Variable Gravity Research Facility (VGRF) should be developed in earth orbit as a gravitational research tool and testbed. This paper addresses the requirements and presents preliminary concepts for such a facility.

Remote Sensing in Polarized Light

NASA Technical Reports Server (NTRS)

Whitehead, Victor S.; Coulson, Kinsell L.

1988-01-01

Preliminary analysis of polarized images of earth collected by hand-held cameras on Shuttle Missions 51A, 51G, 51I, and 61A indicate that information of the earth's surface and atmosphere exists in those data. To ensure that follow-on research in polarization is focused upon and that the experiments are properly designed to address specific questions, 26 scientists with past experience and interest in polarization observations met at the Lyndon B. Johnson Space Center on November 3 to 5, 1987. This conference report summarizes the discussions and provides the recommendations of the group for follow-on research.

Impact of seasonal and postglacial surface displacement on global reference frames

NASA Astrophysics Data System (ADS)

Krásná, Hana; Böhm, Johannes; King, Matt; Memin, Anthony; Shabala, Stanislav; Watson, Christopher

2014-05-01

The calculation of actual station positions requires several corrections which are partly recommended by the International Earth Rotation and Reference Systems Service (IERS) Conventions (e.g., solid Earth tides and ocean tidal loading) as well as other corrections, e.g. accounting for hydrology and atmospheric loading. To investigate the pattern of omitted non-linear seasonal motion we estimated empirical harmonic models for selected stations within a global solution of suitable Very Long Baseline Interferometry (VLBI) sessions as well as mean annual models by stacking yearly time series of station positions. To validate these models we compare them to displacement series obtained from the Gravity Recovery and Climate Experiment (GRACE) data and to hydrology corrections determined from global models. Furthermore, we assess the impact of the seasonal station motions on the celestial reference frame as well as on Earth orientation parameters derived from real and also artificial VLBI observations. In the second part of the presentation we apply vertical rates of the ICE-5G_VM2_2012 vertical land movement grid on vertical station velocities. We assess the impact of postglacial uplift on the variability in the scale given different sampling of the postglacial signal in time and hence on the uncertainty in the scale rate of the estimated terrestrial reference frame.

Modeling of flexible surfaces: A preliminary study

NASA Technical Reports Server (NTRS)

Banks, H. T.; Majda, G.

1983-01-01

The one-dimensional classical scalar string equation which involves linearization about a horizontal reference or equilibrium position is derived. We then derive a model for small motion about a nonhorizontal reference. The implications of our findings to modeling of flexible antenna surfaces such as that in the Maypole Hoop/Column antenna are discussed.

The Web as a Reference Tool: Comparisons with Traditional Sources.

ERIC Educational Resources Information Center

Janes, Joseph; McClure, Charles R.

1999-01-01

This preliminary study suggests that the same level of timeliness and accuracy can be obtained for answers to reference questions using resources in freely available World Wide Web sites as with traditional print-based resources. Discusses implications for library collection development, new models of consortia, training needs, and costing and…

Poly-gamma-Glutamate Capsule-Degrading Enzyme Treatment Enhances Phagocytosis and Killing of Encapsulated Bacillus Anthracis

DTIC Science & Technology

2006-10-14

including the use of extracts of Bacillus pyo- cyaneus to treat anthrax (see reference 2 and references therein) and of Aspergillus fumigatus to...as overexpression could lead to a high level of de- polymerization and a loss of capsule from the bacterial surface. A preliminary proteomic analysis

Preliminary study of the effects of headwater riparian reserves with upslope thinning on stream habitats and amphibians in western Oregon.

Treesearch

D.H. Olson; C. Rugger

2007-01-01

We conducted a preliminary examination of the responses of stream amphibians and instream habitat conditions to alternative riparian buffer zones with forest thinning upslope. Pre- and posttreatment surveys were carried out on 68 headwater stream reaches (including 23 unthinned reference reaches) at 11 sites in western Oregon. Streams were in managed conifer stands 40...

Preliminary Design of the Guidance, Navigation, and Control System of the Altair Lunar Lander

NASA Technical Reports Server (NTRS)

Lee, Allan Y.; Ely, Todd; Sostaric, Ronald; Strahan, Alan; Riedel, Joseph E.; Ingham, Mitch; Wincentsen, James; Sarani, Siamak

2010-01-01

Guidance, Navigation, and Control (GN&C) is the measurement and control of spacecraft position, velocity, and attitude in support of mission objectives. This paper provides an overview of a preliminary design of the GN&C system of the Lunar Lander Altair. Key functions performed by the GN&C system in various mission phases will first be described. A set of placeholder GN&C sensors that is needed to support these functions is next described. To meet Crew safety requirements, there must be high degrees of redundancy in the selected sensor configuration. Two sets of thrusters, one on the Ascent Module (AM) and the other on the Descent Module (DM), will be used by the GN&C system. The DM thrusters will be used, among other purposes, to perform course correction burns during the Trans-lunar Coast. The AM thrusters will be used, among other purposes, to perform precise angular and translational controls of the ascent module in order to dock the ascent module with Orion. Navigation is the process of measurement and control of the spacecraft's "state" (both the position and velocity vectors of the spacecraft). Tracking data from the Earth-Based Ground System (tracking antennas) as well as data from onboard optical sensors will be used to estimate the vehicle state. A driving navigation requirement is to land Altair on the Moon with a landing accuracy that is better than 1 km (radial 95%). Preliminary performance of the Altair GN&C design, relative to this and other navigation requirements, will be given. Guidance is the onboard process that uses the estimated state vector, crew inputs, and pre-computed reference trajectories to guide both the rotational and the translational motions of the spacecraft during powered flight phases. Design objectives of reference trajectories for various mission phases vary. For example, the reference trajectory for the descent "approach" phase (the last 3-4 minutes before touchdown) will sacrifice fuel utilization efficiency in order to provide landing site visibility for both the crew and the terrain hazard detection sensor system. One output of Guidance is the steering angle commands sent to the 2 degree-of-freedom (dof) gimbal actuation system of the descent engine. The engine gimbal actuation system is controlled by a Thrust Vector Control algorithm that is designed taking into account the large quantities of sloshing liquids in tanks mounted on Altair. In this early design phase of Altair, the GN&C system is described only briefly in this paper and the emphasis is on the GN&C architecture (that is still evolving). Multiple companion papers will provide details that are related to navigation, optical navigation, guidance, fuel sloshing, rendezvous and docking, machine-pilot interactions, and others. The similarities and differences of GN&C designs for Lunar and Mars landers are briefly compared.

Annual Geocenter Motion from Space Geodesy and Models

NASA Astrophysics Data System (ADS)

Ries, J. C.

2013-12-01

Ideally, the origin of the terrestrial reference frame and the center of mass of the Earth are always coincident. By construction, the origin of the reference frame is coincident with the mean Earth center of mass, averaged over the time span of the satellite laser ranging (SLR) observations used in the reference frame solution, within some level of uncertainty. At shorter time scales, tidal and non-tidal mass variations result in an offset between the origin and geocenter, called geocenter motion. Currently, there is a conventional model for the tidally-coherent diurnal and semi-diurnal geocenter motion, but there is no model for the non-tidal annual variation. This annual motion reflects the largest-scale mass redistribution in the Earth system, so it essential to observe it for a complete description of the total mass transport. Failing to model it can also cause false signals in geodetic products such as sea height observations from satellite altimeters. In this paper, a variety of estimates for the annual geocenter motion are presented based on several different geodetic techniques and models, and a ';consensus' model from SLR is suggested.

Advanced propulsion for LEO-Moon transport. 1: A method for evaluating advanced propulsion performance

NASA Technical Reports Server (NTRS)

Stern, Martin O.

1992-01-01

This report describes a study to evaluate the benefits of advanced propulsion technologies for transporting materials between low Earth orbit and the Moon. A relatively conventional reference transportation system, and several other systems, each of which includes one advanced technology component, are compared in terms of how well they perform a chosen mission objective. The evaluation method is based on a pairwise life-cycle cost comparison of each of the advanced systems with the reference system. Somewhat novel and economically important features of the procedure are the inclusion not only of mass payback ratios based on Earth launch costs, but also of repair and capital acquisition costs, and of adjustments in the latter to reflect the technological maturity of the advanced technologies. The required input information is developed by panels of experts. The overall scope and approach of the study are presented in the introduction. The bulk of the paper describes the evaluation method; the reference system and an advanced transportation system, including a spinning tether in an eccentric Earth orbit, are used to illustrate it.

Earth Viewing Applications Laboratory (EVAL). Dedicated payload, standard test rack payload, sensor modifications

NASA Technical Reports Server (NTRS)

1976-01-01

The preliminary analysis of strawman earth-viewing shuttle sortie payloads begun with the partial spacelab payload was analyzed. The payloads analyzed represent the two extremes of shuttle sortie application payloads: a full shuttle sortie payload dedicated to earth-viewing applications, and a small structure payload which can fly on a space available basis with another primary shuttle payload such as a free flying satellite. The intent of the dedicated mission analysis was to configure an ambitious, but feasible, payload; which, while rich in scientific return, would also stress the system and reveal any deficiences or problem areas in mission planning, support equipment, and operations. Conversely, the intent of the small structure payload was to demonstrate the ease with which a small, simple, flexible payload can be accommodated on shuttle flights.

A Study of an Optical Lunar Surface Communications Network with High Bandwidth Direct to Earth Link

NASA Technical Reports Server (NTRS)

Wilson, K.; Biswas, A.; Schoolcraft, J.

2011-01-01

Analyzed optical DTE (direct to earth) and lunar relay satellite link analyses, greater than 200 Mbps downlink to 1-m Earth receiver and greater than 1 Mbps uplink achieved with mobile 5-cm lunar transceiver, greater than 1Gbps downlink and greater than 10 Mpbs uplink achieved with 10-cm stationary lunar transceiver, MITLL (MIT Lincoln Laboratory) 2013 LLCD (Lunar Laser Communications Demonstration) plans to demonstrate 622 Mbps downlink with 20 Mbps uplink between lunar orbiter and ground station; Identified top five technology challenges to deploying lunar optical network, Performed preliminary experiments on two of challenges: (i) lunar dust removal and (ii)DTN over optical carrier, Exploring opportunities to evaluate DTN (delay-tolerant networking) over optical link in a multi-node network e.g. Desert RATS.

Solid earth science in the 1990s. Volume 1: Program plan

NASA Technical Reports Server (NTRS)

1991-01-01

This is volume one of a three volume series. A plan for solid earth science research for the next decade is outlined. The following topics are addressed: scientific requirements; status of current research; major new emphasis in the 1990's; interagency and international participation; and the program implementation plan. The following fields are represented: plate motion and deformation; lithospheric structure and evolution; volcanology; land surface (processes of change); earth structure and dynamics; earth rotation and reference frames; and geopotential fields. Other topics of discussion include remote sensing, space missions, and space techniques.

Active Debris Removal mission design in Low Earth Orbit

NASA Astrophysics Data System (ADS)

Martin, Th.; Pérot, E.; Desjean, M.-Ch.; Bitetti, L.

2013-03-01

Active Debris Removal (ADR) aims at removing large sized intact objects ― defunct satellites, rocket upper-stages ― from space crowded regions. Why? Because they constitute the main source of the long-term debris environment deterioration caused by possible future collisions with fragments and worse still with other intact but uncontrolled objects. In order to limit the growth of the orbital debris population in the future (referred to as the Kessler syndrome), it is now highly recommended to carry out such ADR missions, together with the mitigation measures already adopted by national agencies (such as postmission disposal). At the French Space Agency, CNES, and in the frame of advanced studies, the design of such an ADR mission in Low Earth Orbit (LEO) is under evaluation. A two-step preliminary approach has been envisaged. First, a reconnaissance mission based on a small demonstrator (˜500 kg) rendezvousing with several targets (observation and in-flight qualification testing). Secondly, an ADR mission based on a larger vehicle (inherited from the Orbital Transfer Vehicle (OTV) concept) being able to capture and deorbit several preselected targets by attaching a propulsive kit to these targets. This paper presents a flight dynamics level tradeoff analysis between different vehicle and mission concepts as well as target disposal options. The delta-velocity, times, and masses required to transfer, rendezvous with targets and deorbit are assessed for some propelled systems and propellant less options. Total mass budgets are then derived for two end-to-end study cases corresponding to the reconnaissance and ADR missions mentioned above.

Middle Atmosphere Program. Handbook for MAP. Volume 31: Reference models of trace species for the COSPAR international reference atmosphere

NASA Technical Reports Server (NTRS)

Keating, G. M. (Editor)

1989-01-01

A set of preliminary reference atmosphere models of significant trace species which play important roles in controlling the chemistry, radiation budget, and circulation patterns of the atmosphere were produced. These models of trace species distributions are considered to be reference models rather than standard models; thus, it was not crucial that they be correct in an absolute sense. These reference models can serve as a means of comparison between individual observations, as a first guess in inversion algorithms, and as an approximate representation of observations for comparison to theoretical calculations.

A novel methodology for rapid digestion of rare earth element ores and determination by microwave plasma-atomic emission spectrometry and dynamic reaction cell-inductively coupled plasma-mass spectrometry.

PubMed

Helmeczi, Erick; Wang, Yong; Brindle, Ian D

2016-11-01

Short-wavelength infrared radiation has been successfully applied to accelerate the acid digestion of refractory rare-earth ore samples. Determinations were achieved with microwave plasma-atomic emission spectrometry (MP-AES) and dynamic reaction cell - inductively coupled plasma-mass spectrometry (DRC-ICP-MS). The digestion method developed was able to tackle high iron-oxide and silicate matrices using only phosphoric acid in a time frame of only 8min, and did not require perchloric or hydrofluoric acid. Additionally, excellent recoveries and reproducibilities of the rare earth elements, as well as uranium and thorium, were achieved. Digestions of the certified reference materials OREAS-465 and REE-1, with radically different mineralogies, delivered results that mirror those obtained by fusion processes. For the rare-earth CRM OKA-2, whose REE data are provisional, experimental data for the rare-earth elements were generally higher than the provisional values, often exceeding z-values of +2. Determined values for Th and U in this reference material, for which certified values are available, were in excellent agreement. Copyright © 2016 Elsevier B.V. All rights reserved.

Preliminary risk assessment for nuclear waste disposal in space, volume 2

NASA Technical Reports Server (NTRS)

Rice, E. E.; Denning, R. S.; Friedlander, A. L.

1982-01-01

Safety guidelines are presented. Waste form, waste processing and payload fabrication facilities, shipping casks and ground transport vehicles, payload primary container/core, radiation shield, reentry systems, launch site facilities, uprooted space shuttle launch vehicle, Earth packing orbits, orbit transfer systems, and space destination are discussed. Disposed concepts and risks are then discussed.

A Mars orbiter mission design

NASA Astrophysics Data System (ADS)

Castronuovo, Marco M.

1992-08-01

A preliminary study of a new orbiter mission to Mars using an earth gravity assist is presented. The trajectory resulting from this study has been evaluated utilizing Everhart's (1985) integrator RADAU. The mission sequences are described and compared to other proposed mission designs and some mission opportunities for the years 1997 to 2014 are discussed.

Ecosystems and diversity of the Sierra Madre Occidental

Treesearch

M. S. Gonzalez-Elizondo; M. Gonzalez-Elizondo; L. Ruacho Gonzalez; I. L. Lopez Enriquez; F. I . Retana Renteria; J. A. Tena Flores

2013-01-01

The Sierra Madre Occidental (SMO) is the largest continuous ignimbrite plate on Earth. Despite its high biological and cultural diversity and enormous environmental and economical importance, it is yet not well known. We describe the vegetation and present a preliminary regionalization based on physiographic, climatic, and floristic criteria. A confluence of three main...

Rio Grande Lidar Bank Erosion Monitoring: Preliminary 2007-2008 Results and Survey Design Considerations

DTIC Science & Technology

2010-09-01

was reexposed by erosion following the initial event (Figure 9). Erosion of the fan toe in the vicinity of the downstream array is primarily...Digitally Capture the Topography of Sand Dunes in High Spatial Resolution. Earth Surface Processes and Landforms 29:391-398. Queensland, G. 2008

Bimodal Nuclear Thermal Rocket Sizing and Trade Matrix for Lunar, Near Earth Asteroid and Mars Missions

NASA Astrophysics Data System (ADS)

McCurdy, David R.; Krivanek, Thomas M.; Roche, Joseph M.; Zinolabedini, Reza

2006-01-01

The concept of a human rated transport vehicle for various near earth missions is evaluated using a liquid hydrogen fueled Bimodal Nuclear Thermal Propulsion (BNTP) approach. In an effort to determine the preliminary sizing and optimal propulsion system configuration, as well as the key operating design points, an initial investigation into the main system level parameters was conducted. This assessment considered not only the performance variables but also the more subjective reliability, operability, and maintainability attributes. The SIZER preliminary sizing tool was used to facilitate rapid modeling of the trade studies, which included tank materials, propulsive versus an aero-capture trajectory, use of artificial gravity, reactor chamber operating pressure and temperature, fuel element scaling, engine thrust rating, engine thrust augmentation by adding oxygen to the flow in the nozzle for supersonic combustion, and the baseline turbopump configuration to address mission redundancy and safety requirements. A high level system perspective was maintained to avoid focusing solely on individual component optimization at the expense of system level performance, operability, and development cost.

Realizing a terrestrial reference frame using the Global Positioning System

NASA Astrophysics Data System (ADS)

Haines, Bruce J.; Bar-Sever, Yoaz E.; Bertiger, Willy I.; Desai, Shailen D.; Harvey, Nate; Sibois, Aurore E.; Weiss, Jan P.

2015-08-01

We describe a terrestrial reference frame (TRF) realization based on Global Positioning System (GPS) data alone. Our approach rests on a highly dynamic, long-arc (9 day) estimation strategy and on GPS satellite antenna calibrations derived from Gravity Recovery and Climate Experiment and TOPEX/Poseidon low Earth orbit receiver GPS data. Based on nearly 17 years of data (1997-2013), our solution for scale rate agrees with International Terrestrial Reference Frame (ITRF)2008 to 0.03 ppb yr-1, and our solution for 3-D origin rate agrees with ITRF2008 to 0.4 mm yr-1. Absolute scale differs by 1.1 ppb (7 mm at the Earth's surface) and 3-D origin by 8 mm. These differences lie within estimated error levels for the contemporary TRF.

Compilation of Published Estimates of Annual Geocenter Motions Using Space Geodesy

NASA Technical Reports Server (NTRS)

Elosegui, P.

2005-01-01

The definition of the term "geocenter motion" depends on the adopted origin of the reference frame. Common reference frames used in Space Geodesy include: the center of mass of the whole Earth (CM), the center of mass of the Solid Earth without mass load (CE), and the center of figure of the outer surface of the Solid Earth (CF). There are two established definitions of the term geocenter: one, the vector offset of CF relative to CM and, two, the reverse, the vector offset of CM relative to CF. Obviously, their amplitude is the same and their phase differs by 180 deg. Following Dong et al. [2003], we label the first X(sub CF, sup CM) and the second X(sup CF, sup CM) (i.e., the superscript represents the frame, the subscript represents any point in the frame).

An Algorithm for Converting Static Earth Sensor Measurements into Earth Observation Vectors

NASA Technical Reports Server (NTRS)

Harman, R.; Hashmall, Joseph A.; Sedlak, Joseph

2004-01-01

An algorithm has been developed that converts penetration angles reported by Static Earth Sensors (SESs) into Earth observation vectors. This algorithm allows compensation for variation in the horizon height including that caused by Earth oblateness. It also allows pitch and roll to be computed using any number (greater than 1) of simultaneous sensor penetration angles simplifying processing during periods of Sun and Moon interference. The algorithm computes body frame unit vectors through each SES cluster. It also computes GCI vectors from the spacecraft to the position on the Earth's limb where each cluster detects the Earth's limb. These body frame vectors are used as sensor observation vectors and the GCI vectors are used as reference vectors in an attitude solution. The attitude, with the unobservable yaw discarded, is iteratively refined to provide the Earth observation vector solution.

Lord Kelvin and the Age-of-the-Earth Debate: A Dramatization.

ERIC Educational Resources Information Center

Stinner, Art; Tecihman, Jurgen

2003-01-01

Presents a dramatization of a fictitious debate about the age of the earth that takes place at the Royal Institution, London, England, in the year 1872 among Sir William Thomson, T.H. Huxley, Sir Charles Lyell, and Hermann von Helmholtz. (Contains 17 references.) (Author/YDS)

A Question and Answer Guide to Astronomy

NASA Astrophysics Data System (ADS)

Christian, Carol; Roy, Jean-René

2017-03-01

Preface; 1. The sky viewed from Earth; 2. The Earth and Moon system; 3. The Solar System; 4. Stars and stellar systems; 5. Galaxies and the Universe; 6. Life in the Universe; 7. Amateur astronomy; 8. Telescopes and instruments; Unit conversion and basic physical and astronomical measurements; References; Bibliography; Index.

Molecular Dynamic Simulation of Space and Earth-Grown Crystal Structures of Thermostable T1 Lipase Geobacillus zalihae Revealed a Better Structure.

PubMed

Ishak, Siti Nor Hasmah; Aris, Sayangku Nor Ariati Mohamad; Halim, Khairul Bariyyah Abd; Ali, Mohd Shukuri Mohamad; Leow, Thean Chor; Kamarudin, Nor Hafizah Ahmad; Masomian, Malihe; Rahman, Raja Noor Zaliha Raja Abd

2017-09-25

Less sedimentation and convection in a microgravity environment has become a well-suited condition for growing high quality protein crystals. Thermostable T1 lipase derived from bacterium Geobacillus zalihae has been crystallized using the counter diffusion method under space and earth conditions. Preliminary study using YASARA molecular modeling structure program for both structures showed differences in number of hydrogen bond, ionic interaction, and conformation. The space-grown crystal structure contains more hydrogen bonds as compared with the earth-grown crystal structure. A molecular dynamics simulation study was used to provide insight on the fluctuations and conformational changes of both T1 lipase structures. The analysis of root mean square deviation (RMSD), radius of gyration, and root mean square fluctuation (RMSF) showed that space-grown structure is more stable than the earth-grown structure. Space-structure also showed more hydrogen bonds and ion interactions compared to the earth-grown structure. Further analysis also revealed that the space-grown structure has long-lived interactions, hence it is considered as the more stable structure. This study provides the conformational dynamics of T1 lipase crystal structure grown in space and earth condition.

A comparative study of spherical and flat-Earth geopotential modeling at satellite elevations

NASA Technical Reports Server (NTRS)

Parrott, M. H.; Hinze, W. J.; Braile, L. W.; Vonfrese, R. R. B.

1985-01-01

Flat-Earth modeling is a desirable alternative to the complex spherical-Earth modeling process. These methods were compared using 2 1/2 dimensional flat-earth and spherical modeling to compute gravity and scalar magnetic anomalies along profiles perpendicular to the strike of variably dimensioned rectangular prisms at altitudes of 150, 300, and 450 km. Comparison was achieved with percent error computations (spherical-flat/spherical) at critical anomaly points. At the peak gravity anomaly value, errors are less than + or - 5% for all prisms. At 1/2 and 1/10 of the peak, errors are generally less than 10% and 40% respectively, increasing to these values with longer and wider prisms at higher altitudes. For magnetics, the errors at critical anomaly points are less than -10% for all prisms, attaining these magnitudes with longer and wider prisms at higher altitudes. In general, in both gravity and magnetic modeling, errors increase greatly for prisms wider than 500 km, although gravity modeling is more sensitive than magnetic modeling to spherical-Earth effects. Preliminary modeling of both satellite gravity and magnetic anomalies using flat-Earth assumptions is justified considering the errors caused by uncertainties in isolating anomalies.

Numerical modelling of sedimentary structures in rivers on Titan and Earth

NASA Astrophysics Data System (ADS)

Misiura, Katarzyna; Czechowski, Leszek

2016-04-01

On Titan surface we can expect a few different geomorphological forms, e.g. fluvial valley and river channels. In our research we use numerical model of the river to determine the limits of different fluvial parameters that play important roles in evolution of the rivers on Titan and on Earth. We have found that transport of sediments as suspended load is the main way of transport for Titan. We also determined the range of the river's parameters for which braided river is developed rather than meandering river. 2. Introduction Titan is a very special body in the Solar System. It is the only moon that has dense atmosphere and flowing liquid on its surface. The Cassini-Huygens mission has found on Titan meandering rivers, and indicated processes of erosion, transport of solid material and its sedimentation. This work is aimed to investigate the similarity and differences between these processes on Titan and the Earth. 3. Numerical model The dynamical analysis of the considered rivers is performed using the package CCHE modified for the specific conditions on Titan. The package is based on the Navier-Stokes equations for depth-integrated two dimensional, turbulent flow and three dimensional convection-diffusion equation of sediment transport. For more information about equations see [1]. 4. Parameters of the model We considered our model for a few different parameters of liquid and material transported by a river. For Titan we consider liquid corresponding to a Titan's rain (75% methane, 25% nitrogen), for Earth, of course, the water. Material transported in rivers on Titan is water ice, for Earth - quartz. Other parameters of our model are: inflow discharge, outflow level, grain size of sediments etc. For every calculation performed for Titan's river similar calculations are performed for terrestrial ones. 5. Results and Conclusions The results of our simulation show the differences in behaviour of the flow and of sedimentation on Titan and on the Earth. Our preliminary results indicate that suspended load is the main way of transport in simulated Titan's conditions. We also indicate that braided rivers appears for larger range of slope on Titan (e.g. S=0.01-0.04) than on Earth (e.g. S=0.004-0.009). Also, for the same type of river, the grain size on Titan is at least 10 times larger than on Earth (1 cm for Titan versus 1 mm for the Earth). It is very interesting that on Titan braided rivers appear even for very little discharge (e.g. Q=30m3/s) and for very large grain size (e.g. 10 cm). In the future we plan the experimental modelling in sediment basin to confirm results from computer modelling. Acknowledgements We are very grateful to Yaoxin Zhang and Yafei Jia from National Center for Computational Hydroscience and Engineering for providing their program - CCHE2D. References [1] Misiura, K., Czechowski, L., 2015. Numerical modelling of sedimentary structures in rivers on Earth and Titan. Geological Quarterly, 59(3): 565-580.

Rivers on Titan - numerical modelling of sedimentary structures

NASA Astrophysics Data System (ADS)

Misiura, Katarzyna; Czechowski, Leszek

2016-07-01

On Titan surface we can expect a few different geomorphological forms, e.g. fluvial valley and river channels. In our research we use numerical model of the river to determine the limits of different fluvial parameters that play important roles in evolution of the rivers on Titan and on Earth. We have found that transport of sediments as suspended load is the main way of transport for Titan [1]. We also determined the range of the river's parameters for which braided river is developed rather than meandering river. Similar, parallel simulations for rivers deltas are presented in [2]. Introduction Titan is a very special body in the Solar System. It is the only moon that has dense atmosphere and flowing liquid on its surface. The Cassini-Huygens mission has found on Titan meandering rivers, and indicated processes of erosion, transport of solid material and its sedimentation. This work is aimed to investigate the similarity and differences between these processes on Titan and the Earth. Numerical model The dynamical analysis of the considered rivers is performed using the package CCHE modified for the specific conditions on Titan. The package is based on the Navier-Stokes equations for depth-integrated two dimensional, turbulent flow and three dimensional convection-diffusion equation of sediment transport. For more information about equations see [1]. Parameters of the model We considered our model for a few different parameters of liquid and material transported by a river. For Titan we consider liquid corresponding to a Titan's rain (75% methane, 25% nitrogen), for Earth, of course, the water. Material transported in rivers on Titan is water ice, for Earth - quartz. Other parameters of our model are: inflow discharge, outflow level, grain size of sediments etc. For every calculation performed for Titan's river similar calculations are performed for terrestrial ones. Results and Conclusions The results of our simulation show the differences in behaviour of the flow and of the sedimentation on Titan and on the Earth. Our preliminary results indicate that suspended load is the main way of transport in simulated Titan's conditions. We also indicate that braided rivers appears for larger range of slope on Titan (e.g. S=0.01-0.04) than on Earth (e.g. S=0.004-0.009). Also, for the same type of river, the grain size on Titan is at least 10 times larger than on Earth (1 cm for Titan versus 1 mm for the Earth). It is very interesting that on Titan braided rivers appear even for very little discharge (e.g. Q=30m3/s) and for very large grain size (e.g. 10 cm). In the future we plan the experimental modelling in sediment basin to confirm results from computer modelling. Acknowledgements We are very grateful to Yaoxin Zhang and Yafei Jia from National Center for Computational Hydroscience and Engineering for providing their program - CCHE2D. References [1] Misiura, K., Czechowski, L., 2015. Numerical modelling of sedimentary structures in rivers on Earth and Titan. Geological Quarterly, 59(3): 565-580. [2] Witek, P., Czechowski, L., 2015. Dynamical modeling of river deltas on Titan and Earth. Planet. Space. Sci., 105: 65-79.

A preliminary experiment definition for video landmark acquisition and tracking

NASA Technical Reports Server (NTRS)

Schappell, R. T.; Tietz, J. C.; Hulstrom, R. L.; Cunningham, R. A.; Reel, G. M.

1976-01-01

Six scientific objectives/experiments were derived which consisted of agriculture/forestry/range resources, land use, geology/mineral resources, water resources, marine resources and environmental surveys. Computer calculations were then made of the spectral radiance signature of each of 25 candidate targets as seen by a satellite sensor system. An imaging system capable of recognizing, acquiring and tracking specific generic type surface features was defined. A preliminary experiment definition and design of a video Landmark Acquisition and Tracking system is given. This device will search a 10-mile swath while orbiting the earth, looking for land/water interfaces such as coastlines and rivers.

LinkedEarth and 21st century paleoclimatology: reducing data friction through standard development

NASA Astrophysics Data System (ADS)

Khider, D.; Emile-Geay, J.; McKay, N.; Garijo, D.; Ratnakar, V.; Gil, Y.; Zhu, F.

2017-12-01

Paleoclimate observations are crucial to assessing current climate change in the context of past variations. However, these observations usually come in non-standard formats, forcing paleogeoscientists to spend a significant fraction of their time searching and accessing the data they need, in the form they need it. In the 21st century, we should do much better. The EarthCube-supported LinkedEarth project is manifesting a better future by creating an online platform that (1) enables the curation of a publicly-accessible database by paleoclimate experts themselves, and (2) fosters the development of community standards. In 2016, a workshop on paleoclimate data standards served as a focal point to initiate this process. Workshop participants identified the necessity to distinguish a set of essential, recommended, and desired properties for each dataset. A consensus emerged that these levels are archive-specific, as what is needed to intelligently re-use marine-annually resolved records could be quite different than what is needed to intelligently re-use an ice core records, for instance. It was therefore decided that archive-centric working groups (WGs) would be best positioned to elaborate and discuss the components of a data standard for their specific sub-field of paleoclimatology. It is also critical to ensure interoperability between standards to enable multi-proxy investigations; to that end, longitudinal WGs were created, and the LinkedEarth leadership regularly monitors WG activity to ensure cross-pollination and consistency. These WGs carried out their discussions on the LinkedEarth online platform, providing the foundation for a preliminary standard that could be voted on by the rest of the community. In this presentation, I will showcase this preliminary paleoclimate data standard and dwell on community engagement through the use of online polls on the LinkedEarth platform, Twitter, and email-distributed online surveys. Finally, I will demonstrate how these standards have enabled cutting-edge data-analytic tools to be built in R and Python and applied to a wider array of datasets than ever possible before.

The Oxford Companion to the Earth

NASA Astrophysics Data System (ADS)

Hancock, Paul L.

2001-06-01

Here is a wealth of information on planet Earth, ranging from the heights of the ionsphere down to the red-hot molten core. Written by some 200 expert contributors, and illustrated with over 600 pictures, including 16 pages of color plates, The Oxford Companion to the Earth offers 900 alphabetically arranged entries that cover everything from deserts and wetlands to mountains, caves, glaciers, and coral reefs. There are articles on natural phenomena such as tornadoes and tsunamis, volcanoes and earthquakes, jet streams and weather fronts; on the history of Earth, including the origin of life, Burgess Shale fauna, dinosaurs, and the Ice Ages; on key figures, such as Agassiz, Cuvier, Darwin, and Lamarck; and on such important ecological concerns as acid rain, the ozone layer, industrial waste disposal, and the greenhouse effect. The Companion also examines the great sources of wealth to be found in the Earth, from coal and oil to gold, silver, and diamonds, and many curious land formations, from sinkholes and fiords to yardangs and quicksand. There are brief entries on rock types, from amber to travertine, and extensive essays on cutting-edge aspects of the earth sciences, such as seismology and marine geology. The Companion includes extensive cross-references, suggested further reading, an index, and many useful appendices, with a geological timescale, facts and figures about the Earth, and a table of chemical elements. The Oxford Companion to the Earth is a unique reference work, offering unrivaled coverage of our home planet. Generously illustrated and vividly written, it is a treasure house of information for all lovers of natural history, geology, and ecology, whether professional or amateur.

Preliminary Findings on the Effects of Self-Referring and Evaluative Stimuli on Stimulus Equivalence Class Formation

ERIC Educational Resources Information Center

Merwin, Rhonda M.; Wilson, Kelly G.

2005-01-01

Thirty-two subjects completed 2 stimulus equivalence tasks using a matching-to-sample paradigm. One task involved direct reinforcement of conditional discriminations designed to produce derived relations between self-referring stimuli (e.g., me, myself, I) and positive evaluation words (e.g., whole, desirable, perfect). The other task was designed…

Frequently Asked Questions: An Effective Way to Store and Retrieve Reference Information?

ERIC Educational Resources Information Center

Stalker, John C.; Murfin, Marjorie E.

1996-01-01

Describes a computerized program presently being developed on the World Wide Web, which is designed to locate and store reference information through the use of FAQs (Frequently Asked Questions). Reports a preliminary investigation of the adequacy of FAQs to cover a sample of questions on American government, politics, elections and law. (AEF)

PRELIMINARY RESULTS OF EPA'S PERFORMANCE EVALUATION OF FEDERAL REFERENCE METHODS AND FEDERAL EQUIVALENT METHODS FOR COARSE PARTICULATE MATTER

EPA Science Inventory

The main objective of this study is to evaluate the performance of sampling methods for potential use as a Federal Reference Method (FRM) capable of providing an estimate of coarse particle (PMc: particulate matter with an aerodynamic diameter between 2.5 µm and 10 µm) ...

Selected Bibliography on Culture and Cultural Materials, Preliminary Edition. Series A: Reference Materials, Human Relations in Cultural Context.

ERIC Educational Resources Information Center

Condon, E. C.; And Others

Included in this bibliography are references to resources and materials available to the teacher and educator on human relations and cultural education. The bibliography is divided into three sections on culture, specific culture, and adult bilingual-bicultural education. The section on culture presents background information on the relation of…

On transformation between international celestial and terrestrial reference systems

NASA Astrophysics Data System (ADS)

Bretagnon, P.; Brumberg, V. A.

2003-09-01

Based on the current IAU hierarchy of the relativistic reference systems, practical formulae for the transformation between barycentric (BCRS) and geocentric (GCRS) celestial reference systems are derived. BCRS is used to refer to ICRS, International Celestial Reference System. This transformation is given in four versions, dependent on the time arguments used for BCRS (TCB or TDB) and for GCRS (TCG or TT). All quantities involved in these formulae have been tabulated with the use of the VSOP theories (IMCCE theories of motion of the major planets). In particular, these formulae may be applied to account for the indirect relativistic third-body perturbations in motion of Earth's satellites and Earth's rotation problem. We propose to use the SMART theory (IMCCE theory of Earth's rotation) in constructing the Newtonian three-dimensional spatial rotation transformation between GCRS and ITRS, the International Terrestrial Reference System. This transformation is compared with two other versions involving extra angular variables currently used by IERS, the International Earth Rotation Service. It is shown that the comparison of these three forms of the same transformation may be greatly simplified by using the proposed composite rotation formula. Tables 1-20 of Appendix B containing the initial terms of the VSOP-based series for the BCRS<->GCRS transformation are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/408/387. The work on ICRS<->GCRS transformation with the use of VSOP theories was done in February-March 2002 during the stay of the second author in IMCCE. The authors hoped to complete the second part concerning GCRS<->ITRS transformation with the use of SMART theory in September 2002 during the visit of the first author to IAA. The grave disease of Pierre Bretagnon which tragically resulted in his death on November 17, 2002, did not permit us to complete this work. The aim to improve SMART theory by taking into account the indirect relativistic third-body perturbations as indicated in the paper also remains unachieved. The second author is publishing this paper in memoriam of

The Expanding Universe: Time, Space and Spirit--Keys to Scientific Literacy Series.

ERIC Educational Resources Information Center

Stonebarger, Bill

Nearly every culture has made important discoveries about the universe. Most cultures have searched for a better understanding of the cosmos and how the earth and human life relate. The discussion in this booklet considers time, space, and spirit. Time refers to a sense of history; space refers to geography; and spirit refers to life and thought.…

Geoscience laser altimeter system-stellar reference system

NASA Astrophysics Data System (ADS)

Millar, Pamela S.; Sirota, J. Marcos

1998-01-01

GLAS is an EOS space-based laser altimeter being developed to profile the height of the Earth's ice sheets with ~15 cm single shot accuracy from space under NASA's Mission to Planet Earth (MTPE). The primary science goal of GLAS is to determine if the ice sheets are increasing or diminishing for climate change modeling. This is achieved by measuring the ice sheet heights over Greenland and Antarctica to 1.5 cm/yr over 100 km×100 km areas by crossover analysis (Zwally 1994). This measurement performance requires the instrument to determine the pointing of the laser beam to ~5 urad (1 arcsecond), 1-sigma, with respect to the inertial reference frame. The GLAS design incorporates a stellar reference system (SRS) to relate the laser beam pointing angle to the star field with this accuracy. This is the first time a spaceborne laser altimeter is measuring pointing to such high accuracy. The design for the stellar reference system combines an attitude determination system (ADS) with a laser reference system (LRS) to meet this requirement. The SRS approach and expected performance are described in this paper.

The Calibration of the DSCOVR EPIC Multiple Visible Channel Instrument Using MODIS and VIIRS as a Reference

NASA Technical Reports Server (NTRS)

Haney, Conor; Doeling, David; Minnis, Patrick; Bhatt, Rajendra; Scarino, Benjamin; Gopalan, Arun

2016-01-01

The Deep Space Climate Observatory (DSCOVR), launched on 11 February 2015, is a satellite positioned near the Lagrange-1 (L1) point, carrying several instruments that monitor space weather, and Earth-view sensors designed for climate studies. The Earth Polychromatic Imaging Camera (EPIC) onboard DSCOVR continuously views the sun-illuminated portion of the Earth with spectral coverage in the UV, VIS, and NIR bands. Although the EPIC instrument does not have any onboard calibration abilities, its constant view of the sunlit Earth disk provides a unique opportunity for simultaneous viewing with several other satellite instruments. This arrangement allows the EPIC sensor to be inter-calibrated using other well-characterized satellite instrument reference standards. Two such instruments with onboard calibration are MODIS, flown on Aqua and Terra, and VIIRS, onboard Suomi-NPP. The MODIS and VIIRS reference calibrations will be transferred to the EPIC instrument using both all-sky ocean and deep convective clouds (DCC) ray-matched EPIC and MODIS/VIIRS radiance pairs. An automated navigation correction routine was developed to more accurately align the EPIC and MODIS/VIIRS granules. The automated navigation correction routine dramatically reduced the uncertainty of the resulting calibration gain based on the EPIC and MODIS/VIIRS radiance pairs. The SCIAMACHY-based spectral band adjustment factors (SBAF) applied to the MODIS/ VIIRS radiances were found to successfully adjust the reference radiances to the spectral response of the specific EPIC channel for over-lapping spectral channels. The SBAF was also found to be effective for the non-overlapping EPIC channel 10. Lastly, both ray-matching techniques found no discernable trends for EPIC channel 7 over the year of publically released EPIC data.

All-Sky Earth Occultation Observations with the Fermi Gamma Ray Burst Monitor

NASA Technical Reports Server (NTRS)

Wilson-Hodge, C. A.; Beklen, E.; Bhat, P. N.; Briggs, M.; Camero-Arranz, A.; Case, G.; Chaplin, V.; Cherry, M.; Connaughton, V.; Finger, M.;

Gravity anomaly detection: Apollo/Soyuz

NASA Technical Reports Server (NTRS)

Vonbun, F. O.; Kahn, W. D.; Bryan, J. W.; Schmid, P. E.; Wells, W. T.; Conrad, D. T.

1976-01-01

The Goddard Apollo-Soyuz Geodynamics Experiment is described. It was performed to demonstrate the feasibility of tracking and recovering high frequency components of the earth's gravity field by utilizing a synchronous orbiting tracking station such as ATS-6. Gravity anomalies of 5 MGLS or larger having wavelengths of 300 to 1000 kilometers on the earth's surface are important for geologic studies of the upper layers of the earth's crust. Short wavelength Earth's gravity anomalies were detected from space. Two prime areas of data collection were selected for the experiment: (1) the center of the African continent and (2) the Indian Ocean Depression centered at 5% north latitude and 75% east longitude. Preliminary results show that the detectability objective of the experiment was met in both areas as well as at several additional anomalous areas around the globe. Gravity anomalies of the Karakoram and Himalayan mountain ranges, ocean trenches, as well as the Diamantina Depth, can be seen. Maps outlining the anomalies discovered are shown.

Overview of a Preliminary Destination Mission Concept for a Human Orbital Mission to the Martial Moons

NASA Technical Reports Server (NTRS)

Mazanek, D. D.; Abell, P. A.; Antol, J.; Barbee, B. W.; Beaty, D. W.; Bass, D. S.; Castillo-Rogez, J. C.; Coan, D. A.; Colaprete, A.; Daugherty, K. J.;

Earthing: health implications of reconnecting the human body to the Earth's surface electrons.

PubMed

Chevalier, Gaétan; Sinatra, Stephen T; Oschman, James L; Sokal, Karol; Sokal, Pawel

2012-01-01

Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits-including better sleep and reduced pain-from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance.

Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons

PubMed Central

Chevalier, Gaétan; Sinatra, Stephen T.; Oschman, James L.; Sokal, Karol; Sokal, Pawel

2012-01-01

Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits—including better sleep and reduced pain—from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance. PMID:22291721

A Numerical-Analytical Approach to Modeling the Axial Rotation of the Earth

NASA Astrophysics Data System (ADS)

Markov, Yu. G.; Perepelkin, V. V.; Rykhlova, L. V.; Filippova, A. S.

2018-04-01

A model for the non-uniform axial rotation of the Earth is studied using a celestial-mechanical approach and numerical simulations. The application of an approximate model containing a small number of parameters to predict variations of the axial rotation velocity of the Earth over short time intervals is justified. This approximate model is obtained by averaging variable parameters that are subject to small variations due to non-stationarity of the perturbing factors. The model is verified and compared with predictions over a long time interval published by the International Earth Rotation and Reference Systems Service (IERS).

U.S. satellite proposals, 1945-49

NASA Technical Reports Server (NTRS)

Saegesser, L. D.

1977-01-01

Views concerning the possibility of the development of multistage rockets capable of orbiting the earth had been expressed by von Braun during an interview with members of a U.S. technical intelligence team in 1945. Recommendations to adopt a program with the ultimate objective of launching an earth satellite were submitted in October 1945 by a committee established within the Navy Bureau of Aeronautics. In 1946 it was recommended by the Aeronautical Board that the services proceed independently with their satellite studies. A report concerning the 'preliminary design of an experimental world-circling spaceship' was published by RAND on May 2, 1946. RAND in early 1949 was again asked to study for the Air Force the possible uses of earth satellites. The reasons which prevented at that time a further development and implementation of initial concepts and study results are examined

Variable optical filters for earth-observation imaging minispectrometers

NASA Astrophysics Data System (ADS)

Piegari, A.; Bulir, J.; Krasilnikova, A.; Dami, M.; Harnisch, B.

2017-11-01

Small-dimension, low-mass spectrometers are useful for both Earth observation and planetary missions. A very compact multi-spectral mini-spectrometer that contains no moving parts, can be constructed combining a graded-thickness filter, having a spatially variable narrow-band transmission, to a CCD array detector. The peak wavelength of the transmission filter is moving along one direction of the filter surface, such that each line of a two-dimensional array detector, equipped with this filter, will detect radiation in a different pass band. The spectrum of interest for image spectrometry of the Earth surface is very wide, 400-1000nm. This requirement along with the need of a very small dimension, makes this filter very difficult to manufacture. Preliminary results on metal-dielectric wedge filters, with a gradient of the transmission peak wavelength equal to 60nm/mm, are reported.

Overview of the Mars Sample Return Earth Entry Vehicle

NASA Technical Reports Server (NTRS)

Dillman, Robert; Corliss, James

2008-01-01

NASA's Mars Sample Return (MSR) project will bring Mars surface and atmosphere samples back to Earth for detailed examination. Langley Research Center's MSR Earth Entry Vehicle (EEV) is a core part of the mission, protecting the sample container during atmospheric entry, descent, and landing. Planetary protection requirements demand a higher reliability from the EEV than for any previous planetary entry vehicle. An overview of the EEV design and preliminary analysis is presented, with a follow-on discussion of recommended future design trade studies to be performed over the next several years in support of an MSR launch in 2018 or 2020. Planned topics include vehicle size for impact protection of a range of sample container sizes, outer mold line changes to achieve surface sterilization during re-entry, micrometeoroid protection, aerodynamic stability, thermal protection, and structural materials selection.

Project APEX: Advanced manned exploration of the Martian moon Phobos

NASA Technical Reports Server (NTRS)

Eisley, Joe G.; Akers, Jim

1992-01-01

A preliminary design has been developed for a manned mission to the Martian moon Phobos. The spacecraft is to carry a crew of five and will be launched from Low Earth Orbit in the year 2010. The outbound trajectory to Mars uses a gravitational assisted swingby of Venus and takes eight months to complete. The stay at Phobos is scheduled for 60 days. During this time, the crew will be busily engaged in setting up a prototype fuel processing facility. The vehicle will then return to Earth orbit after a total mission duration of 656 days. The spacecraft is powered by three nuclear thermal rockets which also provide the primary electrical power via dual mode operation. The overall spacecraft length is 110 m, and the total mass departing from Low Earth Orbit is 900 metric tons.

Delta II ICESat-2 Booster Arrival

NASA Image and Video Library

2018-03-09

A United Launch Alliance Delta II booster arrives at NASA's Building 836, the Spacecraft Labs Telemetry Station at Vandenberg Air Force Base in California. It will be offloaded and begin preliminary checkouts and preflight processing for launch of the agency's Ice, Cloud and land Elevation Satellite-2, or ICESat-2. Liftoff from Space Launch Complex-2 at Vandenberg is scheduled for Sept. 12, 2018, and will be the last for the venerable Delta II rocket. Once in orbit, the satellite is designed to measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System. ICESat-2 will help scientists investigate why, and how much, Earth's frozen and icy areas are changing. These area make up Earth's the cryosphere.

Delta II ICESat-2 Booster Offload onto Transporter

NASA Image and Video Library

2018-04-16

At NASA's Building 836, the Spacecraft Labs Telemetry Station at Vandenberg Air Force Base in California, a United Launch Alliance Delta II booster has been removed from its shipping container. Preliminary checkouts and preflight processing will begin leading to launch of the agency's Ice, Cloud and land Elevation Satellite-2, or ICESat-2. Liftoff from Space Launch Complex-2 at Vandenberg is scheduled for Sept. 12, 2018, and will be the last for the venerable Delta II rocket. Once in orbit, the satellite is designed to measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System. ICESat-2 will help scientists investigate why, and how much, Earth's frozen and icy areas are changing. These area make up Earth's the cryosphere.

Delta II ICESat-2 Booster Offload onto Transporter

NASA Image and Video Library

2018-04-16

A United Launch Alliance Delta II booster arrives at NASA's Building 836, the Spacecraft Labs Telemetry Station at Vandenberg Air Force Base in California. It will be offloaded and begin preliminary checkouts and preflight processing for launch of the agency's Ice, Cloud and land Elevation Satellite-2, or ICESat-2. Liftoff from Space Launch Complex-2 at Vandenberg is scheduled for Sept. 12, 2018, and will be the last for the venerable Delta II rocket. Once in orbit, the satellite is designed to measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System. ICESat-2 will help scientists investigate why, and how much, Earth's frozen and icy areas are changing. These area make up Earth's the cryosphere.

Science News of the Year.

ERIC Educational Resources Information Center

Science News, 1987

1987-01-01

Provides a review of science news stories reported in "Science News" during 1987. References each item to the volume and page number in which the subject was addressed. Contains references on astronomy, behavior, biology, biomedicine, chemistry, earth sciences, environment, mathematics and computers, paleontology and anthropology, physics, science…

Mines, prospects, and occurrences of metallic (excluding gold), pegmatite, and rare-earth mineral commodities in the Greenville 1 degree by 2 degrees Quadrangle, South Carolina, Georgia, and North Carolina

USGS Publications Warehouse

D'Agostino, John P.; Zupan, Alan Jon; Maybin, Arthur H.; Abrams, Charlotte E.; German, Jerry M.

1994-01-01

All of the known mines, prospects, and occurrences of metallic (excluding gold, pegmatite, and rare-earth mineral commodities for the Greenville 1° x 2° quadrangle are tabulated in this report. The table lists, in consecutive order for each county (fig. 1), the map number of each item, which correlates and locates the item on the accompanying Greenville 1° x 2° quadrangle map. The known name of the feature; the 7.5' topographic map on the which the commodity site is located; the Universal Transverse Mercator (UTM) northing and easting grid coordinates from the appropriate 7.5' topographic map; the commodity; remarks; and references are also listed. Some locations are known, but many sites are not verified and their locations are only approximate. References are listed in References Cited and referred to by number to save space.

Flight Mechanics Project

NASA Technical Reports Server (NTRS)

Steck, Daniel

2009-01-01

This report documents the generation of an outbound Earth to Moon transfer preliminary database consisting of four cases calculated twice a day for a 19 year period. The database was desired as the first step in order for NASA to rapidly generate Earth to Moon trajectories for the Constellation Program using the Mission Assessment Post Processor. The completed database was created running a flight trajectory and optimization program, called Copernicus, in batch mode with the use of newly created Matlab functions. The database is accurate and has high data resolution. The techniques and scripts developed to generate the trajectory information will also be directly used in generating a comprehensive database.

The 30/20 GHz demonstration system SSUS-D/BSE

NASA Technical Reports Server (NTRS)

1981-01-01

The systems consisting of a 30/20 GHz communication satellite featuring a multiple fixed beam and scanning beam antenna, SS-TDMA, onboard processing and high power TWT's and IMPATT amplifiers, a trunking space-diversity Earth station, a customer premise system (CPS) portable Earth station and a Master Control Station. Hardware, software and personnel are included to build and launch one satellite and to carry on a two year experimentation and demonstration period of advanced Ka-band systems concepts and technology. Included are first level plans identifying all tasks, a schedule for system development and an assessment of critical technology and risk and a preliminary experiments plan.

Three orbital transfer vehicles

NASA Technical Reports Server (NTRS)

1990-01-01

Aerospace engineering students at the Virginia Polytechnic Institute and State University undertook three design projects under the sponsorship of the NASA/USRA Advanced Space Design Program. All three projects addressed cargo and/or crew transportation between low Earth orbit and geosynchronous Earth orbit. Project SPARC presents a preliminary design of a fully reusable, chemically powered aeroassisted vehicle for a transfer of a crew of five and a 6000 to 20000 pound payload. The ASTV project outlines a chemically powered aeroassisted configuration that uses disposable tanks and a relatively small aerobrake to realize propellant savings. The third project, LOCOST, involves a reusable, hybrid laser/chemical vehicle designed for large cargo (up to 88,200 pounds) transportation.

Protein crystal growth aboard the U.S. Space Shuttle flights STS-31 and STS-32

NASA Technical Reports Server (NTRS)

Delucas, Lawrence J.; Smith, Craig D.; Carter, Daniel C.; Twigg, Pam; He, Xiao-Min; Snyder, Robert S.; Weber, Patricia C.; Schloss, J. V.; Einspahr, H. M.; Clancy, L. L.

1992-01-01

Results obtained from the Shuttle flight STS-32 flown in January 1990, and preliminary results from the most recent Shuttle flight, STS-31, flown in April 1990, are presented. Crystals grown in microgravity environment include Canavalin, isocitrate lyase, human serum albumin, and Anti-HPr Fab. It is concluded that about 20 percent of proteins flown exhibit better morphologies or better quality data than their earth-grown counterparts. About 40 percent do not yield crystals at all and the remaining 40 percent yield crystals that are either too small for X-ray analysis or produce data of poorer quality than the best earth-grown crystals.

On meteor-generated infrasound. [propagation characteristics during entry into earth atmosphere

NASA Technical Reports Server (NTRS)

Revelle, D. O.

1976-01-01

The characteristics of generation and propagation of infrasonic pressure waves excited during meteor entry into the earth's atmosphere are studied. Existing line source blast wave theory is applied to infrasonic airwave data from four bright fire-balls. It is shown that the strong shock behavior of the blast wave is confined to a cylinderical region with a radius proportional to the product of the meteor Mach number and its diameter. A description of the wave form far from the source is provided. Infrasonic data reported elsewhere are analyzed. All the results should be considered as preliminary, and additional work is under way to refine the estimates obtained.

Amino Acids from a Comet

NASA Technical Reports Server (NTRS)

Cook, Jamie Elisla

2009-01-01

NASA's Stardust spacecraft returned samples from comet 81P/Wild 2 to Earth in January 2006. Examinations of the organic compounds in cometary samples can reveal information about the prebiotic organic inventory present on the early Earth and within the early Solar System, which may have contributed to the origin of life. Preliminary studies of Stardust material revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds (cometary- vs. terrestrial contamination) could not be identified. We have recently measured the carbon isotopic ratios of these amino acids to determine their origin, leading to the first detection of a coetary amino acid.

Porphyrin as an ideal biomarker in the search for extraterrestrial life.

PubMed

Suo, Zhiyong; Avci, Recep; Schweitzer, Mary Higby; Deliorman, Muhammedin

2007-08-01

A key issue in astrobiological research is identifying target molecules that are unambiguously biological in origin and can be easily detected and recognized. We suggest porphyrin derivatives as an ideal target, because these chromophores are global in distribution and found in virtually all living organisms on Earth, including microorganisms that may approximate the early evolution of life on Earth. We discuss the inherent qualities that make porphyrin ideally suited for astrobiological research and discuss methods for detecting porphyrin molecules in terrestrial sedimentary environments. We present preliminary data to support the use of ToFSIMS as a powerful technique in the identification of porphyrins.

International Laser Ranging Service (ILRS) 2003-2004 Annual Report

NASA Technical Reports Server (NTRS)

Pearlman, Michael (Editor); Noll, Carey (Editor)

2005-01-01

The International Laser Ranging Service (ILRS) organizes and coordinates Satellite Laser Ranging (SLR) and Lunar Laser Ranging (LLR) to support programs in geodetic, geophysical, and lunar research activities and provides the International Earth Rotation and Reference Systems Service (IERS) with products important to the maintenance of an accurate International Terrestrial Reference Frame (ITRF). This reference frame provides the stability through which systematic measurements of the Earth can be made over thousands of kilometers, decades of time, and evolution of measurement technology. This 2003-2004 ILRS annual report is comprised of individual contributions from ILRS components within the international geodetic community for the years 2003-2004. The report documents changes and progress of the ILRS and is also available on the ILRS Web site at http://ilrs.gsfc.nasa.gov/reports/ilrs_reports/ilrsar_2003.html.

77 FR 2974 - Longview Energy Exchange, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-20

... system; (2) a single lower reservoir dam constructed of earth fill materials with an internal dam drainage system; (3) concrete inlet-outlet structures at both upper reservoirs equipped with trash racks..., using the eComment system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your name...

76 FR 75542 - Porcupine Dam Hydropower Project; Notice of Preliminary Permit Application Accepted for Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-02

.... The proposed project would consist of the existing Porcupine reservoir, powerhouse with three turbines..., earth-filled embankment, has a total storage capacity of 13,000 acre-feet and a water surface area of 190 acres at full pool elevation of 5,383 feet above mean sea level. The turbines total 560 kilowatts...

76 FR 18756 - Kahawai Power 5, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-05

... feasibility of the Wailua Reservoir Water Power (Wailua Reservoir project) to be located on the Wailua.... The proposed project will utilize flows from the existing 1,400- foot-long earth-fill dam on the Wailua Reservoir, which is owned and operated by State of Hawaii's Department of Land and Natural...

Environmental networks for large-scale monitoring of Earth and atmosphere

NASA Astrophysics Data System (ADS)

Maurodimou, Olga; Kolios, Stavros; Konstantaras, Antonios; Georgoulas, George; Stylios, Chrysostomos

2013-04-01

Installation and operation of instrument/sensor networks are proven fundamental in the monitoring of the physical environment from local to global scale. The advances in electronics, wireless communications and informatics has led to the development of a huge number of networks at different spatial scales that measure, collect and store a wide range of environmental parameters. These networks have been gradually evolved into integrated information systems that provide real time monitoring, forecasts and different products from the initial collected datasets. Instrument/sensor networks have nowadays become important solutions for environmental monitoring, comprising a basic component of fully automated systems developing worldwide that contribute in the efforts for a sustainable Earth's environment (e.g. Hart et al., 2006, Othman et al., 2012). They are also used as a source of data for models parameterization and as verification tools for accuracy assessment techniques of the satellite imagery. Environmental networks can be incorporated into decision support systems (e.g Rizzi et al., 2012) providing informational background along with data from satellites for decision making, manage problems, suggest solutions and best practices for a sustainable management of the environment. This is a comparative study aiming to examine and highlight the significant role of existing instrument/sensor networks for large-scale monitoring of environmental issues, especially atmospheric and marine environment as well as weather and climate. We provide characteristic examples of integrated systems based on large scale instrument/sensor networks along with other sources of data (like satellite datasets) as informational background to measure, identify, monitor, analyze and forecast a vast series of atmospheric parameters (like CO2, O3, particle matter and solar irradiance), weather, climate and their impacts (e.g., cloud systems, lightnings, rainfall, air and surface temperature, humidity, winds) and marine environment (salinity, water quality, sea surface temperature among others). "ZEUS" lightning detection system (Chronis et al. 2006, Lagouvardos et al. 2009), "UVnet" system that is primarily referred to the UltaViolet solar irradiance (Bais et al. 2006, Kazantzidis et al. 2006) and "GLOBcolour" system for seas monitoring, are some characteristic examples of systems that use networks of instruments/sensors to monitor relative parameters. The chosen examples are focused on the European continent. Basic operating principles of these networks, their usefulness, restrictions and their perspectives in the environmental real time basis monitoring and forecast, are also described. References Bais, A.F., Meleti, C. Kazantzidis, A., Topaloglou, C., Zerefos, C.S., Kosmidis, E. 2006. Greek UV Network: Results and perspectives after three years. 8th Conference on Meteorology - Climatology and Atmospheric Physics, 24-25 May, Athens, Greece. Chronis, T., Anagnostou, E. 2006. Evaluation of a Long-Range Lightning Detection Network with Receivers in Europe and Africa. IEEE Transactions on Geoscience and Remote Sensing, 44, 1504-1510. Hart, K.J., Martinez, K. 2006. Environmental Sensor Networks: A revolution in the Earth system science? Earth-Science Reviews, 78, 178-19. Kazantzidis, A., Bais, A.F, Topaloglou, C., Garane, K., Zempila, M., Meleti, C., Zerefos, C.S. 2006. Quality assurance of the Greek UV Network: preliminary results from the pilot phase operation. Proceedings of SPIE Europe Remote Sensing of Clouds and the Atmosphere XI, vol. 6362, 636229-1 - 636229-10, Stockholm, Sweden, 11-14 September. Lagouvardos, K., Kotroni, V, Betz, D-H., Schmidt, K. 2009. A comparison of lightning data provided by ZEUS and LINET networks over Western Europe. Natural Hazards and Earth Systems Sciences, 9, 1713-1717. Maritorena, S., D'Andon, O.H.F., Mangin, A., Siegel, D.A., 2010. Merged satellite ocean color data products using bio-optical model: Characteristics, benefits and issues. Remote Sensing of Environment, 114, 1791-1804. Othman, M.F., Shazali K., 2012. Wireless Network Applications: A study in environment monitoring system. Procedia Engineering, 41, 1204-1210. Rizzi, J., Torresan, S., Zabeo, A., Gallina, V., Critto, A., Marcomini, A., 2012. A GIS-based Decision Support System to support the implementation of integrated coastal zone management - preliminary results from the PEGASO project. Proceedings of the AGILE' 2012 International Conference on Geographical Information Science, Avignon, April, 24-27.

Atom Interferometry: A Matter Wave Clock and a Measurement of α

NASA Astrophysics Data System (ADS)

Estey, Brian; Lan, Shau-Yu; Kuan, Pei-Chen; Hohensee, Michael; Haslinger, Philipp; Kehayias, Pauli; English, Damon; Müller, Holger

2012-06-01

Developments in large-momentum transfer beamsplitters (eg. Bragg diffraction) and conjugate Ramsey-Bord'e interferometers have enabled atom interferometers with unparalleled size and sensitivity. The atomic wave packet separation is large enough that the Coriolis force due to the earth's rotation reduces interferometer contrast. We compensate for this effect using a tip-tilt mirror, improving our contrast by up to a factor of 3.5, allowing pulse separations of up to 250 ms with 10k beamsplitters. This interferometer can be used to make a precise measurement of the recoil frequency (h/m) and thus the fine structure constant. The interferometer also gives us indirect access to the Compton frequency (νC≡mc^2/h) oscillations of the matter wave, since h/m is simply c^2/νC. Using an optical frequency comb we reference the interferometer's laser frequency to a multiple of a cesium atom's recoil frequency. This self-referenced interferometer thus locks a local oscillator to a specified fraction of the cesium Compton frequency, with a fractional stability of 2 pbb over several hours. This has potential application in redefining the kilogram in terms of the second. We also present a preliminary measurement of the fine structure constant.

Geodesy, a Bibliometric Approach for 2000-2006

NASA Astrophysics Data System (ADS)

Vazquez, G.; Landeros, C. F.

2007-12-01

In recent years, bibliometric science has been frequently applied in the development and evaluation of scientific research. This work presents a bibliometric analysis for the research work performed in the field of geodesy "science of the measurement and mapping of the earth surface including its external gravity field". The objective of this work is to present a complete overview of the generated research on this field to assemble and study the most important publications occurred during the past seven years. The analysis was performed including the SCOPUS and WEB OF SCIENCE databases for all the geodetic scientific articles published between 2000 and 2006. The search profile was designed considering a strategy to seek for titles and article descriptors using the terms geodesy and geodetic and some other terms associated with the topics: geodetic surfaces, vertical measurements, reference systems and frames, modern space-geodetic techniques and satellite missions. Some preliminary results had been achieved specifically Bradford law of distribution for journals and education institutes, and Lotka's law for authors that also includes the cooperation between countries in terms of writing together scientific articles. In the particular case of distributions, the model suggested by Egghe (2002) was adopted for determining the cores.

Updated Heliostorm Warning Mission: Enhancements Based on New Technology

NASA Technical Reports Server (NTRS)

Young, Roy M.

2010-01-01

The Heliostorm (also referred to as Geostorm) mission has been regarded as the best choice for the first application of solar sail technology. The objective of Heliostorm is to obtain data from an orbit station slightly displaced from the ecliptic at or nearer to the Sun than 0.98 AU, which places it twice as close to the sun as Earth's natural L1 point at 0.993 AU. Heliostorm has been the subject of several mission studies over the past decade, with the most complete study conducted in 1999 in conjunction with a proposed New Millennium Program (NMP) Space Technology 5 (ST-5) flight opportunity. Recently, over a two and one-half year period dating from 2002 through 2005, NASA s In-Space Propulsion Technology Program (ISTP) matured solar sail technology from laboratory components to fully integrated systems, demonstrated in as relevant a space environment as could feasibly be simulated on the ground. Work under this program has yielded promising results for enhanced Heliostorm mission performance. This paper will present the preliminary results of an updated Heliostorm mission design study including the enhancements incorporated during the design, development, analysis and testing of the system ground demonstrator.

Short-period cyclic loading system for in situ X-ray observation of anelastic properties at high pressure.

PubMed

Yoshino, Takashi; Yamazaki, Daisuke; Tange, Yoshinori; Higo, Yuji

2016-10-01

To determine the anelastic properties of materials of the Earth's interior, a short-period cyclic loading system was installed for in situ X-ray radiographic observation under high pressure to the multi-anvil deformation DIA press at the bending magnet beam line BL04B1 at SPring-8. The hydraulic system equipped with a piston controlled by a solenoid was designed so as to enable producing smooth sinusoidal stress in a wide range of oscillation period from 0.2 to 100 s and generating variable amplitudes. Time resolved X-ray radiography imaging of the sample and reference material provides their strain as a function of time during cyclic loading. A synchrotron X-ray radiation source allows us to resolve their strain variation with time even at the short period (<1 s). The minimum resolved strain is as small as 10 -4 , and the shortest oscillation period to detect small strain is 0.5 s. Preliminary experimental results exhibited that the new system can resolve attenuation factor Q -1 at upper mantle conditions. These results are in quantitative agreement with previously reported data obtained at lower pressures.

High Temperature Degradation of Advanced Thermal and Environmental Barrier Coatings (TEBCs) by CaO-MgO-Al2O3-SiO2 (CMAS)

NASA Technical Reports Server (NTRS)

Costa, Gustavo; Zhu, Dongming

2017-01-01

There is increasing interest in the degradation studies of thermal and environmental barrier coatings (TEBCs) of gas turbines by molten CaO-MgO-Al2O3-SiO2 (CMAS). CMAS minerals are usually referred as silica-containing sand dust and volcano ash materials that are carried by the intake air into gas turbines, e.g. aircraft engines. The low-melting deposits react at high temperatures (1000C) with the coating materials. This causes degradation and accelerated coating failure of the static and rotating components of the turbine engines. We discuss some preliminary results of the reactions between CMAS and Rare-Earth (RE Y, Yb, Dy, Gd, Nd and Sm) oxide stabilized ZrO2 or HfO2 systems, and the stability of the resulting oxides and silicates. Plasma sprayed hollow tube samples (outer diameter 4.7 mm, wall thickness 0.76 mm and 26 mm height) were half filled with CMAS powder, wrapped and sealed with platinum foil, and heat- treated at 1310 C for 5h. Samples were characterized by differential scanning calorimetry, X-ray diffraction and cross section electron microscopy analysis.

Thermoelasticity of Fe2+-bearing bridgmanite

NASA Astrophysics Data System (ADS)

Shukla, Gaurav; Wu, Zhongqing; Hsu, Han; Floris, Andrea; Cococcioni, Matteo; Wentzcovitch, Renata M.

2015-03-01

We present local density approximation augmented by the Hubbard-type correction calculations of high-temperature elastic properties of bridgmanite with composition (Mg(1-x)Fex2+)SiO3 for 0≤×≤0.125. Results of elastic moduli and acoustic velocities for the Mg end-member (x=0) agree very well with the latest high-pressure and high-temperature experimental measurements. In the iron-bearing system, we focus particularly on the change in thermoelastic parameters across the state change that occurs in ferrous iron above ˜30 GPa, often attributed to a high-spin (HS) to intermediate-spin (IS) crossover but explained by first-principles calculations as a lateral displacement of substitutional iron in the perovskite cage. We show that the measured effect of this change on the equation of state of this system can be explained by the lateral displacement of substitutional iron and not by the HS to IS crossover. The calculated elastic properties of (Mg0.875Fe0.1252+)SiO3 along an adiabatic mantle geotherm somewhat overestimate longitudinal velocities but produce densities and shear velocities quite consistent with the Preliminary Reference Earth Model data throughout most of the lower mantle.

Preliminary Evaluation of Altitude Scaling for Turbofan Engine Ice Crystal Icing

NASA Technical Reports Server (NTRS)

Tsao, Jen-Ching

2017-01-01

Preliminary evaluation of altitude scaling for turbofan engine ice crystal icing simulation was conducted during the 2015 LF11 engine icing test campaign in PSL.The results showed that a simplified approach for altitude scaling to simulate the key reference engine ice growth feature and associated icing effects to the engine is possible. But special considerations are needed to address the facility operation limitation for lower altitude engine icing simulation.

Preliminary results from the portable standard satellite laser ranging intercomparison with MOBLAS-7

NASA Technical Reports Server (NTRS)

Selden, Michael; Varghese, Thomas K.; Heinick, Michael; Oldham, Thomas

1993-01-01

Conventional Satellite Laser Ranging (SLR) instrumentation has been configured and successfully used to provide high-accuracy laboratory measurements on the LAGEOS-2 and TOPEX cube-corner arrays. The instrumentation, referred to as the Portable Standard, has also been used for field measurements of satellite ranges in tandem with MOBLAS-7. Preliminary results of the SLR measurements suggest that improved range accuracy can be achieved using this system. Results are discussed.

Design, Development and Preliminary Student Evaluation of Virtual Field Guides as aids to teaching and learning in the Earth sciences

NASA Astrophysics Data System (ADS)

Stott, Tim

2010-05-01

In Universities the benefits of teaching and learning through fieldwork has been brought under closer examination in recent years (e.g. Andrews et al., 2003) and the notion of supporting fieldwork in the Geography, Earth and Environmental Science (GEES) disciplines has been gathering momentum over the past decade as evidenced by conferences on ‘Supporting fieldwork using information technology' (Maskall et al., 2007) and a Higher Education Academy GEES Virtual Fieldwork Conference at University of Worcester (May 2007). Virtual environments and e-learning resources have been shown to help students become active rather than passive learners by appealing to their multi-sensory learning ability with interactive media (Fletcher et al., 2002; 2007). Research on glacial and fluvial processes has been conducted since 2003 by Liverpool John Moores University (LJMU) staff, sometimes in collaboration with other Universities, at field sites in the French Alps, Swiss Alps and Cariboo Mountains in British Columbia. A virtual field guide (VFG) (www.virtualalps.co.uk) has been developed which uses maps, site photos, panorama movies, video clips, a google earth tour, student exercises using hydrological and glacial datasets collected in the field and revision exercises. A preliminary evaluation of this learning resource has been carried out with two groups of LJMU students and an article written (Stott et al. 2009a). The Ingleton Waterfalls VFG (http://www.ljmu.ac.uk/BIE/ingleton/) was developed by LJMU staff to meet the needs of Foundation degree and undergraduate students. A workshop was presented at the Earth Science Teachers Association 2008 Annual Conference at LJMU, and a subsequent article written (Stott et al. 2009b). The final section of this presentation will summarise some staff perspectives and raises some questions and issues concerned with development and accessibility of VFGs in the light of new developments of a ‘semantic web' at LJMU (Carmichael, 2009). Andrews, J., Kneale, P., Sougnez, Y., Stewart, M., and Stott, T. A. (2003). Carrying out Pedagogic research into the Constructive Alignment of Fieldwork. Planet Special Edition 5: Linking Teaching and Research and undertaking Pedagogic Research in Geography, Earth and Environmental Sciences, 51-52. Carmichael, P. (2008) ‘The Semantic Web and ‘Web 3.0' in: Selwyn, N. (ed.) Education 2.0? Designing the web for teaching and learning. London: ESRC Teaching and Learning Research Programme. Fletcher, S., France, D., Moore, K. and Robinson, G. (2002). Fieldwork education and technology: A GEES perspective, Planet 4, 17-19. Fletcher, S., France, D., Moore, K. and Robinson, G. (2007). Putting technology into fieldwork education: A pedagogic evaluation. Journal of Geography in Higher Education 31, 2, 319 - 330 Maskall, J., Stokes, A., Truscott, J. B., Bridge, A., Magnier, K. and Calderbank, V. (2007) Supporting fieldwork using information technology, Planet 18, 18-21. Stott, TA., Nuttall, AM. and McCloskey, J. (2009a) Design, Development and Student Evaluation of a Virtual Alps Field Guide www.virtualalps.co.uk. Planet 22, 64-71. Publication of the Higher Education Academy Subject Centre for Geography, Earth and Environmental Sciences, Learning & Teaching Support Network www.gees.ac.uk/planet/. Stott, TA, Clark, H., Milson, C., McCloskey, J. and Crompton, K. (2009b) The Ingleton Waterfalls Virtual Field Trip: Design, Development and Preliminary Evaluation, Teaching Earth Sciences 34 (1), 13-19, Magazine of the Earth Science Teachers Association.

Astrobiology Workshop: Leadership in Astrobiology

NASA Technical Reports Server (NTRS)

DeVincenzi, D. (Editor); Briggs, G.; Cohen, M.; Cuzzi, J.; DesMarais, D.; Harper, L.; Morrison, D.; Pohorille, A.

1996-01-01

Astrobiology is defined in the 1996 NASA Strategic Plan as 'The study of the living universe.' At NASA's Ames Research Center, this endeavor encompasses the use of space to understand life's origin, evolution, and destiny in the universe. Life's origin refers to understanding the origin of life in the context of the origin and diversity of planetary systems. Life's evolution refers to understanding how living systems have adapted to Earth's changing environment, to the all-pervasive force of gravity, and how they may adapt to environments beyond Earth. Life's destiny refers to making long-term human presence in space a reality, and laying the foundation for understanding and managing changes in Earth's environment. The first Astrobiology Workshop brought together a diverse group of researchers to discuss the following general questions: Where and how are other habitable worlds formed? How does life originate? How have the Earth and its biosphere influenced each other over time? Can terrestrial life be sustained beyond our planet? How can we expand the human presence to Mars? The objectives of the Workshop included: discussing the scope of astrobiology, strengthening existing efforts for the study of life in the universe, identifying new cross-disciplinary programs with the greatest potential for scientific return, and suggesting steps needed to bring this program to reality. Ames has been assigned the lead role for astrobiology by NASA in recognition of its strong history of leadership in multidisciplinary research in the space, Earth, and life sciences and its pioneering work in studies of the living universe. This initial science workshop was established to lay the foundation for what is to become a national effort in astrobiology, with anticipated participation by the university community, other NASA centers, and other agencies. This workshop (the first meeting of its kind ever held) involved life, Earth, and space scientists in a truly interdisciplinary sharing of ideas related to life in the universe, and by all accounts was a resounding success.

A proposed International Geomagnetic Reference Field for 1965- 1985.

USGS Publications Warehouse

Peddie, N.W.; Fabiano, E.B.

1982-01-01

A set of spherical harmonic models describing the Earth's main magnetic field from 1965 to 1985 has been developed and is proposed as the next revision of the International Geomagnetic Reference Field (IGRF). A tenth degree and order spherical harmonic model of the main field was derived from Magsat data. A series of eighth degree and order spherical harmonic models of the secular variation of the main field was derived from magnetic observatory annual mean values. Models of the main field at 1965, 1970, 1975, and 1980 were obtained by extrapolating the main-field model using the secular variation models.-Authors spherical harmonic models Earth main magnetic field Magsat data

Nonsingular expansions of the gravity potential and its derivatives at satellite altitudes in the ellipsoidal coordinate system

NASA Astrophysics Data System (ADS)

Vershkov, A. N.; Petrovskaya, M. S.

2016-11-01

The series in ellipsoidal harmonics for derivatives of the Earth's gravity potential are used only on the reference ellipsoid enveloping the Earth due to their very complex mathematical structure. In the current study, the series in ellipsoidal harmonics are constructed for first- and second-order derivatives of the potential at satellite altitudes; their structure is similar to the series on the reference ellipsoid. The point P is chosen at a random satellite altitude; then, the ellipsoid of revolution is described, which passes through this point and is confocal to the reference ellipsoid. An object-centered coordinate system with the origin at the point P is considered. Using a sequence of transformations, the nonsingular series in ellipsoidal harmonics is constructed for first and second derivatives of the potential in the object-centered coordinate system. These series can be applied to develop a model of the Earth's potential, based on combined use of surface gravitational force measurements, data on the satellite orbital position, its acceleration, or measurements of the gravitational force gradients of the first and second order. The technique is applicable to any other planet of the Solar System.

Referral Consultant: An Expert System for Guiding Teachers in Referring Students for Special Education Placement. Final Report.

ERIC Educational Resources Information Center

Baer, Richard; And Others

In light of evidence indicating that referral itself often predicts student placement, an expert system was designed to assist educators to reduce bias in the process of referring students with suspected disabilities. A preliminary review of the literature looks at teacher perceptions as a predictor of handicapping conditions, referral bias, and…

Assessing Teachers' Comprehension of What Matters in Earth Science

NASA Astrophysics Data System (ADS)

Penuel, W. R.; Kreikemeier, P.; Venezky, D.; Blank, J. G.; Davatzes, A.; Davatzes, N.

2006-12-01

Curricular standards developed for individual U.S. States tell teachers what they should teach. Most sets of standards are too numerous to be taught in a single year, forcing teachers to make decisions about what to emphasize in their curriculum. Ideally, such decisions would be based on what matters most in Earth science, namely, the big ideas that anchor scientific inquiry in the field. A measure of teachers' ability to associate curriculum standards with fundamental concepts in Earth science would help K-12 program and curriculum developers to bridge gaps in teachers' knowledge in order to help teachers make better decisions about what is most important to teach and communicate big ideas to students. This paper presents preliminary results of an attempt to create and validate a measure of teachers' comprehension of what matters in three sub-disciplines of Earth science. This measure was created as part of an experimental study of teacher professional development in Earth science. It is a task that requires teachers to take their state's curriculum standards and identify which standards are necessary or supplemental to developing students' understanding of fundamental concepts in the target sub-disciplines. To develop the task, a team of assessment experts and educational researchers asked a panel of four Earth scientists to identify key concepts embedded within middle school standards for the state of Florida. The Earth science panel reached a consensus on which standards needed to be taught in order to develop understanding of those concepts; this was used as a basis for comparison with teacher responses. Preliminary analysis of the responses of 44 teachers who participated in a pilot validation study identified differences between teachers' and scientists' maps of standards to big ideas in the sub-disciplines. On average, teachers identified just under one-third of the connections seen by expert Earth scientists between the concepts and their state standards. Teachers with higher levels of agreement also had a higher percentage of standards identified that were "off-grade," meaning that they saw connections to standards that they were not themselves required to teach but that nonetheless were relevant to developing student understanding of a particular concept. This result is consistent with the premise that to make good decisions about what to teach, teachers need to be able to identify relevant standards from other grade levels that are connected to the big ideas of a discipline (Shulman, 1986, Educ. Res. 15:4-14).

Kinematics of Laying an Automated Weapon System

DTIC Science & Technology

2017-07-19

mathematical transformation is required to move the firing solution from its reference frame to a reference frame that is meaningful to the weapon system. This...Procedures 2 Conventions and Variable Definitions 2 Rotation Matrices 5 Transformation of a Vector 5 Conversion Between Cartestian and Spherical...Coordinate Systems 6 Transformation of Earth Referenced Lay to Platform Reference Frame 6 Results and Discussions 7 Conclusions 8 Bibliography 9

Environment modelling in near Earth space: Preliminary LDEF results

NASA Technical Reports Server (NTRS)

Coombs, C. R.; Atkinson, D. R.; Wagner, J. D.; Crowell, L. B.; Allbrooks, M.; Watts, A. J.

1992-01-01

Hypervelocity impacts by space debris cause not only local cratering or penetrations, but also cause large areas of damage in coated, painted or laminated surfaces. Features examined in these analyses display interesting morphological characteristics, commonly exhibiting a concentric ringed appearance. Virtually all features greater than 0.2 mm in diameter possess a spall zone in which all of the paint was removed from the aluminum surface. These spall zones vary in size from approximately 2 - 5 crater diameters. The actual craters in the aluminum substrate vary from central pits without raised rims, to morphologies more typical of craters formed in aluminum under hypervelocity laboratory conditions for the larger features. Most features also possess what is referred to as a 'shock zone' as well. These zones vary in size from approximately 1 - 20 crater diameters. In most cases, only the outer-most layer of paint was affected by this impact related phenomenon. Several impacts possess ridge-like structures encircling the area in which this outer-most paint layer was removed. In many ways, such features resemble the lunar impact basins, but on an extremely reduced scale. Overall, there were no noticeable penetrations, bulges or spallation features on the backside of the tray. On Row 12, approximately 85 degrees from the leading edge (RAM direction), there was approximately one impact per 15 cm(exp 2). On the trailing edge, there was approximately one impact per 72 cm(exp 2). Currently, craters on four aluminum experiment trays from Bay E09, directly on the leading edge are being measured and analyzed. Preliminary results have produced more than 2200 craters on approximately 1500 cm(exp 2) - or approximately 1 impact per 0.7 cm(exp 2).

Measuring the earth's rotation and orientation with GPS

NASA Technical Reports Server (NTRS)

Freedman, Adam P.

1992-01-01

The possibilities for providing precise and frequent measurements of earth's orientation in space by using GPS technology are reviewed. In particular, attention is given to the concepts as polar motion and Universal Time, definition of reference frames for unambiguous measurements of earth's rotations, and data processing strategies. Some of the results achieved to date are examined, and it is shown that Universal Time changes can be measured using GPS with an accuracy of better than 100 microseconds over a few hours. Finally, future plans are discussed.

Analyze satellite-tracking laser data in order to study satellite ephemerides, solid-Earth and ocean tides and laser system performance

NASA Technical Reports Server (NTRS)

Gaposchkin, E. M.

1981-01-01

The decrease in the semimajor axis of Lageos is considerably larger than expected. Gravitational effects, reference system effects, solar radiation pressure, Earth albedo pressure, neutral atmospheric drag, the Poynting Robertson Effect, and electrodynamic effects were used in explaining the observations. Quick look data provided are used to determine the Earth's polar motion and length of day. This process is routine, and provides these geophysical data every five days.

The Global Geodetic Observing System: Recent Activities and Accomplishments

NASA Astrophysics Data System (ADS)

Gross, R. S.

2017-12-01

The Global Geodetic Observing System (GGOS) of the International Association of Geodesy (IAG) provides the basis on which future advances in geosciences can be built. By considering the Earth system as a whole (including the geosphere, hydrosphere, cryosphere, atmosphere and biosphere), monitoring Earth system components and their interactions by geodetic techniques and studying them from the geodetic point of view, the geodetic community provides the global geosciences community with a powerful tool consisting mainly of high-quality services, standards and references, and theoretical and observational innovations. The mission of GGOS is: (a) to provide the observations needed to monitor, map and understand changes in the Earth's shape, rotation and mass distribution; (b) to provide the global frame of reference that is the fundamental backbone for measuring and consistently interpreting key global change processes and for many other scientific and societal applications; and (c) to benefit science and society by providing the foundation upon which advances in Earth and planetary system science and applications are built. The goals of GGOS are: (1) to be the primary source for all global geodetic information and expertise serving society and Earth system science; (2) to actively promote, sustain, improve, and evolve the integrated global geodetic infrastructure needed to meet Earth science and societal requirements; (3) to coordinate with the international geodetic services that are the main source of key parameters and products needed to realize a stable global frame of reference and to observe and study changes in the dynamic Earth system; (4) to communicate and advocate the benefits of GGOS to user communities, policy makers, funding organizations, and society. In order to accomplish its mission and goals, GGOS depends on the IAG Services, Commissions, and Inter-Commission Committees. The Services provide the infrastructure and products on which all contributions of GGOS are based. The IAG Commissions and Inter-Commission Committees provide expertise and support for the scientific development within GGOS. In summary, GGOS is IAG's central interface to the scientific community and to society in general. Recent activities and accomplishments of the Global Geodetic Observing System will be presented.

Preliminary Analysis of Ground-based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Brad

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Preliminary Analysis of Ground-Based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Bradley; Myers, Jessica; Lorah, John; Webster, Cassandra

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations'' scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Preliminary Experiments for the Assessment of V/W-band Links for Space-Earth Communications

NASA Technical Reports Server (NTRS)

Nessel, James A.; Acosta, Roberto J.; Miranda, Felix A.

2013-01-01

Since September 2012, NASA Glenn Research Center has deployed a microwave profiling radiometer at White Sands, NM, to estimate atmospheric propagation effects on communications links in the V and W bands (71-86GHz). Estimates of attenuation statistics in the millimeter wave due to gaseous and cloud components of the atmosphere show good agreement with current ITU-R models, but fail to predict link performance in the presence of moderate to heavy rain rates, due to the inherent limitations of passive radiometry. Herein, we discuss the preliminary results of these measurements and describe a design for a terrestrial link experiment to validate/refine existing rain attenuation models in the V/Wbands.

Preliminary Experiments for the Assessment of VW-Band Links for Space-Earth Communications

NASA Technical Reports Server (NTRS)

Nessel, James A.; Acosta, Roberto J.; Miranda, Felix A.

2013-01-01

Since September 2012, NASA Glenn Research Center has deployed a microwave profiling radiometer at White Sands, NM, to estimate atmospheric propagation effects on communications links in the V and W bands (71-86GHz). Estimates of attenuation statistics in the millimeter wave due to gaseous and cloud components of the atmosphere show good agreement with current ITU-R models, but fail to predict link performance in the presence of moderate to heavy rain rates, due to the inherent limitations of passive radiometry. Herein, we discuss the preliminary results of these measurements and describe a design for a terrestrial link experiment to validaterefine existing rain attenuation models in the VW-bands.

Compilation of Rare Earth Element Analyses from US Geothermal Fields and Mid Ocean Ridge Hydrothermal Vents

DOE Data Explorer

Andrew Fowler

2015-10-01

Compilation of rare earth element and associated major and minor dissolved constituent analytical data for USA geothermal fields and global seafloor hydrothermal vents. Data is in original units. Reference to and use of this data should be attributed to the original authors and publications according to the provisions outlined therein.

40 CFR 1065.310 - Torque calibration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... force is measured. The lever arm must be perpendicular to gravity (i.e., horizontal), and it must be... known distance along a lever arm. Make sure the weights' lever arm is perpendicular to gravity (i.e... Earth's gravity, as described in § 1065.630. Calculate the reference torque as the weights' reference...

Precession, Nutation and Wobble of the Earth

NASA Astrophysics Data System (ADS)

Dehant, V.; Mathews, P. M.

2015-04-01

Covering both astronomical and geophysical perspectives, this book describes changes in the Earth's orientation, specifically precession and nutation, and how they are observed and computed in terms of tidal forcing and models of the Earth's interior. Following an introduction to key concepts and elementary geodetic theory, the book describes how precise measurements of the Earth's orientation are made using observations of extra-galactic radio-sources by Very Long Baseline Interferometry techniques. It demonstrates how models are used to accurately pinpoint the location and orientation of the Earth with reference to the stars and how to determine variations in its rotation speed. A theoretical framework is also presented that describes the role played by the structure and properties of the Earth's deep interior. Incorporating suggestions for future developments in nutation theory for the next generation models, this book is ideal for advanced-level students and researche! rs in solid Earth geophysics, planetary science and astronomy.

Regional positioning using a low Earth orbit satellite constellation

NASA Astrophysics Data System (ADS)

Shtark, Tomer; Gurfil, Pini

2018-02-01

Global and regional satellite navigation systems are constellations orbiting the Earth and transmitting radio signals for determining position and velocity of users around the globe. The state-of-the-art navigation satellite systems are located in medium Earth orbits and geosynchronous Earth orbits and are characterized by high launching, building and maintenance costs. For applications that require only regional coverage, the continuous and global coverage that existing systems provide may be unnecessary. Thus, a nano-satellites-based regional navigation satellite system in Low Earth Orbit (LEO), with significantly reduced launching, building and maintenance costs, can be considered. Thus, this paper is aimed at developing a LEO constellation optimization and design method, using genetic algorithms and gradient-based optimization. The preliminary results of this study include 268 LEO constellations, aimed at regional navigation in an approximately 1000 km × 1000 km area centered at the geographic coordinates [30, 30] degrees. The constellations performance is examined using simulations, and the figures of merit include total coverage time, revisit time, and geometric dilution of precision (GDOP) percentiles. The GDOP is a quantity that determines the positioning solution accuracy and solely depends on the spatial geometry of the satellites. Whereas the optimization method takes into account only the Earth's second zonal harmonic coefficient, the simulations include the Earth's gravitational field with zonal and tesseral harmonics up to degree 10 and order 10, Solar radiation pressure, drag, and the lunisolar gravitational perturbation.

Insect mycophagy: a preliminary bibliography.

Treesearch

Robert. Fogel

1975-01-01

Insects that feed on fungi are primary dispersal agents for many beneficial and pathogenic species. Nearly 300 references on the subject, published since the mid-19th century are listed in this bibliography.

Low Pressure Nuclear Thermal Rocket (LPNTR) concept

NASA Technical Reports Server (NTRS)

Ramsthaler, J. H.

1991-01-01

A background and a description of the low pressure nuclear thermal system are presented. Performance, mission analysis, development, critical issues, and some conclusions are discussed. The following subject areas are covered: LPNTR's inherent advantages in critical NTR requirement; reactor trade studies; reference LPNTR; internal configuration and flow of preliminary LPNTR; particle bed fuel assembly; preliminary LPNTR neutronic study results; multiple LPNTR engine concept; tank and engine configuration for mission analysis; LPNTR reliability potential; LPNTR development program; and LPNTR program costs.

Environmental assessment overview

NASA Technical Reports Server (NTRS)

Valentino, A. R.

1980-01-01

The assessment program has as its objectives: to identify the environmental issues associated with the SPS Reference System; to prepare a preliminary assessment based on existing data; to suggest mitigating strategies and provide environmental data and guidance to other components of the program as required; and to plan long-range research to reduce the uncertainty in the preliminary assessment. The key environmental issues associated with the satellite power system are discussed and include human health and safety, ecosystems, climate, and interaction with electromagnetic systems.

Feasibility Study of Space Based Solar Power to Tethered Aerostat Systems

NASA Technical Reports Server (NTRS)

Blank, Stephen J.; Leete, Stephen J.; Jaffe, Paul

2013-01-01

The feasibility of two-stage Space-Based Solar Power to Tethered Aerostat to Earth (SSP-TA) system architectures that offer significant advantages over conventional single stage space-to-earth architectures is being studied. There have been many proposals for the transmission of solar power collected in space to the surface of the earth so that solar energy could provide a major part of the electric power requirements on earth. There are, however, serious difficulties in implementing the single stage space-based solar power systems that have been previously studied. These difficulties arise due to: i) the cost of transporting the components needed for the extremely large microwave transmit beaming aperture into space orbit, ii) the even larger collection apertures required on earth, iii) the potential radiation hazard to personnel and equipment on earth, and iv) a lack of flexibility in location of the collection station on the earth. Two candidate system architectures are described here to overcome these difficulties. In both cases a two-stage space to tethered aerostat to earth transmission system (SSP-TA) is proposed. The use of high altitude tethered aerostats (or powered airships) avoids the effects of attenuation of EM energy propagating through the earth s lower atmosphere. This allows the use of beaming frequencies to be chosen from the range of high millimeter (THz) to near-infra-red (NIR) to the visible. This has the potential for: i) greatly reduced transportation costs to space, ii) much smaller receiver collection apertures and ground stations, iii) elimination of the potential radiation hazard to personnel and equipment on earth, and iv) ease in transportation and flexibility in location of the collection station on the earth. A preliminary comparison of system performance and efficiencies is presented.

Evolution of Orion Mission Design for Exploration Mission 1 and 2

NASA Technical Reports Server (NTRS)

Gutkowski, Jeffrey P.; Dawn, Timothy F.; Jedrey, Richard M.

2016-01-01

The evolving mission design and concepts of NASA's next steps have shaped Orion into the spacecraft that it is today. Since the initial inception of Orion, through the Constellation Program, and now in the Exploration Mission frame-work with the Space Launch System (SLS), each mission design concept and program goal have left Orion with a set of capabilities that can be utilized in many different mission types. Exploration Missions 1 and 2 (EM-1 and EM-2) have now been at the forefront of the mission design focus for the last several years. During that time, different Design Reference Missions (DRMs) were built, analyzed, and modified to solve or mitigate enterprise level design trades to ensure a viable mission from launch to landing. The resulting DRMs for EM-1 and EM-2 were then expanded into multi-year trajectory scans to characterize vehicle performance and Earth-Moon geometry trends. This provides Orion's subsystems with stressing reference trajectories to help design their system. Now that Orion has progressed through the Preliminary and Critical Design Re-views (PDR and CDR) there is a general shift in the focus of mission design from aiding the vehicle design to providing mission specific products needed for pre-flight and real time operations. Some of the mission specific products need-ed include analysis of steering law performance, inputs into navigational accura-cy assessments, abort options at any point in the mission for each valid trajecto-ry in the launch window, recontact avoidance between the upper stage and Orion post nominal separation, etc.

That gravity thing

NASA Astrophysics Data System (ADS)

Jewess, Mike

2009-05-01

Your news article "New probe plots Earth's gravity field" (March p11) reports on the European Space Agency's Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) - a satellite that will measure the Earth's gravitational field. It describes the way that g, the acceleration of free fall at the Earth's surface, varies with latitude; this variation is great enough to require adjustment of pendulum clocks between latitudes and also the recalibration of all balances that do not directly compare one mass with a reference mass. The article also notes that the spin of the (effectively fluid) Earth causes it to bulge at the equator, a realization that goes back to Newton's Principia.

Finding a Second Sample of Life on Earth

NASA Astrophysics Data System (ADS)

Davies, P. C. W.; Lineweaver, Charles H.

2005-06-01

If life emerges readily under Earth-like conditions, the possibility arises of multiple terrestrial genesis events. We seek to quantify the probability of this scenario using estimates of the Archean bombardment rate and the fact that life established itself fairly rapidly on Earth once conditions became favorable. We find a significant likelihood that at least one more sample of life, referred to here as alien life, may have emerged on Earth, and could have coexisted with known life. Indeed, it is difficult to rule out the possibility of extant alien life. We offer some suggestions for how an alternative sample of life might be detected.

Near-Earth Objects. Chapter 27

NASA Technical Reports Server (NTRS)

Harris, Alan W.; Drube, Line; McFadden, Lucy A.; Binzel, Richard P.

2014-01-01

A near-Earth object (NEO) is an asteroid or comet orbiting the Sun with a perihelion distance of less than 1.3 Astronomical Units (AU) (1 AU, an astronomical unit, is the mean distance between the Earth and the Sun, around 150 million kilometers). If the orbit of an NEO can bring it to within 0.05 AU of the Earth's orbit, and it is larger than about 120 meters, it is termed a potentially hazardous object (PHO); an object of this size is likely to survive passage through the atmosphere and cause extensive damage on impact. (The acronyms NEA and PHO are used when referring specifically to asteroids.)

OSTA-3 Shuttle payload

NASA Technical Reports Server (NTRS)

Dillman, R. D.; Eav, B. B.; Baldwin, R. R.

1984-01-01

The Office of Space and Terrestrial Applications-3 payload, scheduled for flight on STS Mission 17, consists of four earth-observation experiments. The Feature Identification and Location Experiment-1 will spectrally sense and numerically classify the earth's surface into water, vegetation, bare earth, and ice/snow/cloud-cover, by means of spectra ratio techniques. The Measurement of Atmospheric Pollution from Satellite experiment will measure CO distribution in the middle and upper troposphere. The Imaging Camera-B uses side-looking SAR to create two-dimensional images of the earth's surface. The Large Format Camera/Attitude Reference System will collect metric quality color, color-IR, and black-and-white photographs for topographic mapping.

The first geocenter estimation results using GPS measurements

NASA Technical Reports Server (NTRS)

Malla, R. P.; Wu, S. C.

1990-01-01

The center of mass of the Earth is the natural and unambiguous origin of a geocentric satellite dynamical system. A geocentric reference frame assumes that the origin of its coordinate axes is at the geocenter, in which all relevant observations and results can be referred and in which geodynamic theories or models for the dynamic behavior of Earth can be formulated. In practice, however, a kinematically obtained terrestrial reference frame may assume an origin other than the geocenter. A fast and accurate method of determining origin offset from the geocenter is highly desirable. Global Positioning System (GPS) measurements, because of their abundance and broad distribution, provide a powerful tool to obtain this origin offset in a short period of time. Two effective strategies have been devised. Data from the first Central and South America (Casa Uno) global GPS experiment were studied to demonstrate the ability of recovering the geocenter location with present-day GPS satellites and receivers.

How and Why to Do VLBI on GPS

NASA Technical Reports Server (NTRS)

Dickey, J. M.

2010-01-01

In order to establish the position of the center of mass of the Earth in the International Celestial Reference Frame, observations of the Global Positioning Satellite (GPS) constellation using the IVS network are important. With a good frame-tie between the coordinates of the IVS telescopes and nearby GPS receivers, plus a common local oscillator reference signal, it should be possible to observe and record simultaneously signals from the astrometric calibration sources and the GPS satellites. The standard IVS solution would give the atmospheric delay and clock offsets to use in analysis of the GPS data. Correlation of the GPS signals would then give accurate orbital parameters of the satellites in the ICRF reference frame, i.e., relative to the positions of the astrometric sources. This is particularly needed to determine motion of the center of mass of the earth along the rotation axis.

Towards a Full Waveform Ambient Noise Inversion

NASA Astrophysics Data System (ADS)

Sager, K.; Ermert, L. A.; Boehm, C.; Fichtner, A.

2015-12-01

Noise tomography usually works under the assumption that the inter-station ambient noise correlation is equal to a scaled version of the Green's function between the two receivers. This assumption, however, is only met under specific conditions, for instance, wavefield diffusivity and equipartitioning, zero attenuation, etc., that are typically not satisfied in the Earth. This inconsistency inhibits the exploitation of the full waveform information contained in noise correlations regarding Earth structure and noise generation. To overcome this limitation we attempt to develop a method that consistently accounts for noise distribution, 3D heterogeneous Earth structure and the full seismic wave propagation physics in order to improve the current resolution of tomographic images of the Earth. As an initial step towards a full waveform ambient noise inversion we develop a preliminary inversion scheme based on a 2D finite-difference code simulating correlation functions and on adjoint techniques. With respect to our final goal, a simultaneous inversion for noise distribution and Earth structure, we address the following two aspects: (1) the capabilities of different misfit functionals to image wave speed anomalies and source distribution and (2) possible source-structure trade-offs, especially to what extent unresolvable structure could be mapped into the inverted noise source distribution and vice versa.

Comets and the origins and evolution of life; Proceedings of the Conference, Univ. of Wisconsin, Eau Claire, Sept. 30-Oct. 2, 1991

NASA Technical Reports Server (NTRS)

Thomas, Paul J. (Editor)

1992-01-01

Papers are presented on comets and the formation of biochemical compounds on the primitive earth; the cometary origin of carbon, nitrogen, and water on the earth; comets as a possible source of prebiotic molecules; comet impacts and chemical evolution on the bombarded earth; and cometary supply of terrestrial organics (lessons from the K/T and the present epoch). Other papers are on a computational study of radiation chemical processing in comet nuclei, the origin of the polycyclic aromatic hydrocarbons in meteorites, the fate of organic matter during planetary accretion (preliminary studies of the organic chemistry of experimentally shocked Murchison meteorite), recent observations of interstellar molecules (detection of CCO and a limit on H2C3O), terrestrial and extraterrestrial sources of molecular monochirality, and dark matter in the solar system (hydrogen cyanide polymers).

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

Mainzer, A.; Masiero, J.; Bauer, J.

Enhancements to the science data processing pipeline of NASA's Wide-field Infrared Survey Explorer (WISE) mission, collectively known as NEOWISE, resulted in the detection of >158,000 minor planets in four infrared wavelengths during the fully cryogenic portion of the mission. Following the depletion of its cryogen, NASA's Planetary Science Directorate funded a four-month extension to complete the survey of the inner edge of the Main Asteroid Belt and to detect and discover near-Earth objects (NEOs). This extended survey phase, known as the NEOWISE Post-Cryogenic Survey, resulted in the detection of {approx}6500 large Main Belt asteroids and 86 NEOs in its 3.4more » and 4.6 {mu}m channels. During the Post-Cryogenic Survey, NEOWISE discovered and detected a number of asteroids co-orbital with the Earth and Mars, including the first known Earth Trojan. We present preliminary thermal fits for these and other NEOs detected during the 3-Band Cryogenic and Post-Cryogenic Surveys.« less

Delta II ICESat-2 Booster Offload onto Transporter

NASA Image and Video Library

2018-04-16

At NASA's Building 836, the Spacecraft Labs Telemetry Station at Vandenberg Air Force Base in California, a United Launch Alliance Delta II booster is removed from its shipping container. After it is offloaded, preliminary checkouts and preflight processing will begin leading to launch of the agency's Ice, Cloud and land Elevation Satellite-2, or ICESat-2. Liftoff from Space Launch Complex-2 at Vandenberg is scheduled for Sept. 12, 2018, and will be the last for the venerable Delta II rocket. Once in orbit, the satellite is designed to measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System. ICESat-2 will help scientists investigate why, and how much, Earth's frozen and icy areas are changing. These area make up Earth's the cryosphere.

Concepts for image management and communication system for space vehicle health management

NASA Astrophysics Data System (ADS)

Alsafadi, Yasser; Martinez, Ralph

On a space vehicle, the Crew Health Care System will handle minor accidents or illnesses immediately, thereby eliminating the necessity of early mission termination or emergency rescue. For practical reasons, only trained personnel with limited medical experience can be available on space vehicles to render preliminary health care. There is the need to communicate with medical experts at different locations on earth. Interplanetary Image Management and Communication System (IIMACS) will be a bridge between worlds and deliver medical images acquired in space to physicians at different medical centers on earth. This paper discusses the implementation of IIMACS by extending the Global Picture Archiving and Communication System (GPACS) being developed to interconnect medical centers on earth. Furthermore, this paper explores system requirements of IIMACS and different user scenarios. Our conclusion is that IIMACS is feasible using the maturing technology base of GPACS.

Stats Don't Tell the Whole Story: Using Qualitative Data Analysis of Chat Reference Transcripts to Assess and Improve Services

ERIC Educational Resources Information Center

Mungin, Michael

2017-01-01

In the five years following implementation of a chat reference service at James Madison University (JMU), the service proved very popular but was not closely assessed for quality of service. Using grounded theory and qualitative data analysis techniques, a comprehensive assessment effort was begun in earnest and is in progress. Preliminary results…

Wildland fire management. Volume 2: Wildland fire control 1985-1995. [satellite information system for California fire problems

NASA Technical Reports Server (NTRS)

Saveker, D. R. (Editor)

1973-01-01

The preliminary design of a satellite plus computer earth resources information system is proposed for potential uses in fire prevention and control in the wildland fire community. Suggested are satellite characteristics, sensor characteristics, discrimination algorithms, data communication techniques, data processing requirements, display characteristics, and costs in achieving the integrated wildland fire information system.

High Precision Optical Observations of Space Debris in the Geo Ring from Venezuela

NASA Astrophysics Data System (ADS)

Lacruz, E.; Abad, C.; Downes, J. J.; Casanova, D.; Tresaco, E.

2018-01-01

We present preliminary results to demonstrate that our method for detection and location of Space Debris (SD) in the geostationary Earth orbit (GEO) ring, based on observations at the OAN of Venezuela is of high astrometric precision. A detailed explanation of the method, its validation and first results is available in (Lacruz et al. 2017).

78 FR 61958 - New England Hydropower Company, LLC; Notice of Preliminary Permit Application Accepted for Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-08

... located on Quinnipiac River, near the city of Meriden, in New Haven County, Connecticut. The sole purpose...' express permission. The proposed project would consist of the following: (1) An existing 25-foot-high, 430-foot-long earth embankment dam with four low-level, sluice gates and a 242-foot-long concrete spillway...

75 FR 73062 - Qualified Hydro 27, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-29

... (Howard A. Hanson project) to be located in King County, Washington, near the town of Palmer. The sole... 675-foot-long, 235-foot-high earth and rockfill Howard A. Hanson dam; (2) the existing Howard A. Hanson reservoir, which has a maximum usable storage of 106,000 acre-feet between elevation 1,206 feet...

77 FR 58375 - Inglis Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-20

... consist of the following: (1) An existing 32-foot-high, 3500-foot-long earth filled dam; (2) a reservoir... bypass channel; (4) a 65-foot-wide, 35- foot-long intake structure with a trash rack cleaning system; (5... system at http://www.ferc.gov/docs-filing/ecomment.asp . You must include your name and contact...

PowerSat: A technology demonstration of a solar power satellite

NASA Technical Reports Server (NTRS)

Sigler, Douglas L. (Editor); Riedman, John; Duracinski, Jon; Edwards, Joe; Brown, Garry; Webb, Ron; Platzke, Mike; Yuan, Xiaolin; Rogers, Pete; Khan, Afsar

1994-01-01

PowerSat is a preliminary design strategy for microwave wireless power transfer of solar energy. Solar power satellites convert solar power into microwave energy and use wireless power transmission to transfer the power to the Earth's surface. The PowerSat project will show how new developments in inflatable technology can be used to deploy solar panels and phased array antennas.

Relevance of antarctic microbial ecosystems to exobiology

NASA Technical Reports Server (NTRS)

Mckay, Christopher P.

1993-01-01

Antarctic microbial ecosystems which provide biological and physical analogs that can be used in exobiology are studied. Since the access to extraterrestrial habitats is extremely difficult, terrestrial analogs represent the best opportunity for both formulation and preliminary testing of hypothesis about life. Antarctica, as one of few suitable environments on earth is considered to be a major locus of progress in exobiology.

Millimeter wave propagation measurements using the ATS 5 satellite

NASA Technical Reports Server (NTRS)

Ippolito, L. J.

1972-01-01

The ATS 5 millimeter wave propagation experiment determines long- and short-term attenuation statistics of operational millimeter wavelength earthspace links as functions of defined meteorological conditions. A preliminary analysis of results with 15 GHz downlink and 32 GHz uplink frequency bands indicates that both frequency bands exhibit an excellent potential for utilization in reliable high data rate earth-space communications systems.

Synthesis Study of a 6-Element Non-Uniform Array with Tilted Elements for CLARREO Project

NASA Technical Reports Server (NTRS)

Jamnejad, Vahraz; Hoorfar, Ahmad

2012-01-01

This paper presents the results of a preliminary study of the gain/pattern properties of a 6-element Radio Occultation (RO) array for the proposed CLARREO (Climate Absolute Radiance and Refractivity Observatory (CLARREO) Project. CLARREO is one of the 4 highest priority missions recommended in the National Research Council Earth Science Decadal Survey.

Sensitivity of Landsat image-derived burn severity indices to immediate post-fire effects

Treesearch

A. T. Hudak; S. Lewis; P. Robichaud; P. Morgan; M. Bobbitt; L. Lentile; A. Smith; Z. Holden; J. Clark; R. McKinley

2006-01-01

The USFS Remote Sensing Applications Center (RSAC) and the USGS Center for Earth Resources Observation and Science (EROS) produce Burned Area Reflectance Classification (BARC) maps as a rapid, preliminary indication of burn severity on large wildfire events. Currently the preferred burn severity index is the delta Normalized Burn Ratio (dNBR), which requires NBR values...

75 FR 18189 - Riverbank Minnesota, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... consist of: (1) A new approximately 135-acre, 30-foot-deep upper reservoir constructed of enclosed earth... Internet. See 18 CFR 385.2001(a)(1)(iii) and the instructions on the Commission's Web site under the ``e... filings please go to the Commission's Web site located at http://www.ferc.gov/filing-comments.asp . More...

Definition and preliminary design of the LAWS (Laser Atmospheric Wind Sounder), volume 2, phase 2

NASA Technical Reports Server (NTRS)

1992-01-01

Accurate knowledge of winds is critical to our understanding of the earth's climate and to our ability to predict climate change. Winds are a fundamental component of highly nonlinear interactions between oceans, land surfaces, and the atmosphere. Interactions at these interfaces are the focus of much climate change research. Although wind information is critical for advancing our understanding, currently most of our description of atmospheric motion is obtained indirectly - i.e., derived from observations of temperature and moisture through geostrophic relationships. Direct measurement of winds over the globe is limited to land-based rawinsonde surface stations and a few ship/aircraft reports. Cloud track winds using satellite imagery are calculated but must be used with great care. The LAWS mission objective, therefore, is to provide diurnal and global direct observations of winds - an observation that will incrementally enhance our knowledge of the earth's climate and physical processes responsible for its change. This document is Volume 2 of the LAWS Phase 2 Final Study Report and describes the definition and preliminary design of the LAWS instrument, together with details of the laser breadboard program conducted during the last 18 months of the program.

Overview of the Results of the Organics PET Study of the Cometary Samples from Comet Wild 2 by the Stardust Mission

NASA Technical Reports Server (NTRS)

Sandford, S. A.; Aleon, J.; Alexander, C. M. O'D.; Araki, T.; Bajt, S.; Baratta, G. A.; Borg, J.; Bradley J. P.; Brownlee, D. E.; Brucato, J. R.;

High-time resolution measurements of upstream magnetic field and plasma conditions during flux transfer events at the Earth's dayside magnetopause

NASA Technical Reports Server (NTRS)

Jacob, Jamey D.; Carrell, Cynthia

1993-01-01

We present preliminary results of a study of upstream magnetic field and plasma conditions measured by IRM during flux transfer events observed at the Earth's magnetopause by CCE. This study was designed to determine the importance of various upstream factors in the formation of bipolar magnetic field signatures called flux transfer events (FTEs). Six FTE encounters were examined. In three cases, the two satellites were on similar magnetic field lines. Preliminary investigation showed that fluctuations occurred in the Bz component of the interplanetary magnetic field (IMF) resulting in a southward field preceding the FTE in all three of these cases. In two of these cases, the changes were characterized by a distinct rotation from a strong southward to a strong northward field. There were also accompanying changes in the dynamic and thermal pressure in the solar wind immediately before the FTE was encountered. Examination of the 3D plasma distributions showed that these pulses were due to the addition of energetic upstreaming foreshock particles. There were no consistent changes in either Bz or the plasma pressure at IRM for the three events when the satellites were not connected by the IMF.

Effects of solid/liquid phase fractionation on pH and aqueous species molality in subduction zone fluids

NASA Astrophysics Data System (ADS)

Zhong, X.; Galvez, M. E.

2017-12-01

Metamorphic fluids are a crucial ingredient of geodynamic evolution, i.e. heat transfer, rock mechanics and metamorphic/metasomatic reactions. During crustal evolution at elevated P and T, rock forming components can be effectively fractionated from the reactive rock system by at least two processes: 1. extraction from porous rocks by liquid phases such as solute-bearing (e.g. Na+, Mg2+) aqueous fluids or partial melts. 2. isolation from effective bulk rock composition due to slow intragranular diffusion in high-P refractory phases such as garnet. The effect of phase fractionation (garnet, partial melt and aqueous species) on fluid - rock composition and properties remain unclear, mainly due to a high demand in quantitative computations of the thermodynamic interactions between rocks and fluids over a wide P-T range. To investigate this problem, we build our work on an approach initially introduced by Galvez et al., (2015) with new functionalities added in a MATLAB code (Rubisco). The fluxes of fractionated components in fluid, melt and garnet are monitored along a typical prograde P-T path for a model crustal pelite. Some preliminary results suggest a marginal effect of fractionated aqueous species on fluid and rock properties (e.g. pH, composition), but the corresponding fluxes are significant in the context of mantle wedge metasomatism. Our work provides insight into the role of high-P phase fractionation on mass redistribution between the surface and deep Earth in subduction zones. Existing limitations relevant to our liquid/mineral speciation/fractionation model will be discussed as well. ReferencesGalvez, M.E., Manning, C.E., Connolly, J.A.D., Rumble, D., 2015. The solubility of rocks in metamorphic fluids: A model for rock-dominated conditions to upper mantle pressure and temperature. Earth Planet. Sci. Lett. 430, 486-498.

Orographic forcing of dune forming winds on Titan

NASA Astrophysics Data System (ADS)

Larson, E. J.; Toon, O. B.; Friedson, A. J.

2013-12-01

Cassini has observed hundreds of dune fields on Titan, nearly all of which lie in the tropics and suggest westerly (from west to east) winds dominate at the surface [1,2]. Most GCMs however have obtained easterly surface winds in the tropics, seemingly contradicting the wind direction suggested by the dunes. This has led to an active debate in the community about the origin of the dune forming winds on Titan and their direction and modality. This discussion is mostly driven by a study of Earth dunes seen as analogous to Titan [1,2,3]. One can find examples of dunes on Earth that fit several wind regimes. To date only one GCM, that of Tokano [4,5], has presented detailed analysis of its near surface winds and their dune forming capabilities. Despite the bulk of the wind being easterly, this GCM produces faster westerlies at equinox, thus transporting sand to the east. Our model, the Titan CAM [6], is unable to reproduce the fast westerlies, although it is possible we are not outputting frequently enough to catch them. Our GCM has been updated to include realistic topography released by the Cassini radar team. Preliminary results suggest our tropical wind regime now has net westerly winds in the tropics, albeit weak. References: [1], Lorenz, R. et al. 2006. Science, 312, 724-727. [2], Radebaugh, J. et al. 2008. Icarus, 194, 690-703. [3] Rubin, D. and Hesp, P. 2009. Nature Geoscience 2, 653-658. [4] Tokano, T. 2008. Icarus 194, 243-262. [5] Tokano, T. 2010. Aeolian Research 2, 113-127. [6] Friedson, J. et al. 2009. Planetary Space Science, 57, 1931-1949.

A Climatology of Global Aerosol Mixtures to Support Sentinel-5P and Earthcare Mission Applications

NASA Astrophysics Data System (ADS)

Taylor, M.; Kazadzis, S.; Amaridis, V.; Kahn, R. A.

2015-11-01

Since constraining aerosol type with satellite remote sensing continues to be a challenge, we present a newly derived global climatology of aerosol mixtures to support atmospheric composition studies that are planned for Sentinel-5P and EarthCARE.The global climatology is obtained via application of iterative cluster analysis to gridded global decadal and seasonal mean values of the aerosol optical depth (AOD) of sulfate, biomass burning, mineral dust and marine aerosol as a proportion of the total AOD at 500nm output from the Goddard Chemistry Aerosol Radiation and Transport (GOCART). For both the decadal and seasonal means, the number of aerosol mixtures (clusters) identified is ≈10. Analysis of the percentage contribution of the component aerosol types to each mixture allowed development of a straightforward naming convention and taxonomy, and assignment of primary colours for the generation of true colour-mixing and easy-to-interpret maps of the spatial distribution of clusters across the global grid. To further help characterize the mixtures, aerosol robotic network (AERONET) Level 2.0 Version 2 inversion products were extracted from each cluster‟s spatial domain and used to estimate climatological values of key optical and microphysical parameters.The aerosol type climatology represents current knowledge that would be enhanced, possibly corrected, and refined by high temporal and spectral resolution, cloud-free observations produced by Sentinel-5P and EarthCARE instruments. The global decadal mean and seasonal gridded partitions comprise a preliminary reference framework and global climatology that can help inform the choice of components and mixtures in aerosol retrieval algorithms used by instruments such as TROPOMI and ATLID, and to test retrieval results.

On mantle chemical and thermal heterogeneities and anisotropy as mapped by inversion of global surface wave data

NASA Astrophysics Data System (ADS)

Khan, A.; Boschi, L.; Connolly, J. A. D.

2009-09-01

We invert global observations of fundamental and higher-order Love and Rayleigh surface wave dispersion data jointly at selected locations for 1-D radial profiles of Earth's mantle composition, thermal state, and anisotropic structure using a stochastic sampling algorithm. Considering mantle compositions as equilibrium assemblages of basalt and harzburgite, we employ a self-consistent thermodynamic method to compute their phase equilibria and bulk physical properties (P, S wave velocity and density). Combining these with locally varying anisotropy profiles, we determine anisotropic P and S wave velocities to calculate dispersion curves for comparison with observations. Models fitting data within uncertainties provide us with a range of profiles of composition, temperature, and anisotropy. This methodology presents an important complement to conventional seismic tomography methods. Our results indicate radial and lateral gradients in basalt fraction, with basalt depletion in the upper and enrichment of the upper part of the lower mantle, in agreement with results from geodynamical calculations, melting processes at mid-ocean ridges, and subduction of chemically stratified lithosphere. Compared with preliminary reference Earth model (PREM) and seismic tomography models, our velocity models are generally faster in the upper transition zone (TZ) and slower in the lower TZ, implying a steeper velocity gradient. While less dense than PREM, density gradients in the TZ are also steeper. Mantle geotherms are generally adiabatic in the TZ, whereas in the upper part of the lower mantle, stronger lateral variations are observed. The retrieved anisotropy structure agrees with previous studies indicating positive as well as laterally varying upper mantle anisotropy, while there is little evidence for anisotropy in and below the TZ.

A hybrid systems strategy for automated spacecraft tour design and optimization

NASA Astrophysics Data System (ADS)

Stuart, Jeffrey R.

As the number of operational spacecraft increases, autonomous operations is rapidly evolving into a critical necessity. Additionally, the capability to rapidly generate baseline trajectories greatly expands the range of options available to analysts as they explore the design space to meet mission demands. Thus, a general strategy is developed, one that is suitable for the construction of flight plans for both Earth-based and interplanetary spacecraft that encounter multiple objects, where these multiple encounters comprise a ``tour''. The proposed scheme is flexible in implementation and can readily be adjusted to a variety of mission architectures. Heuristic algorithms that autonomously generate baseline tour trajectories and, when appropriate, adjust reference solutions in the presence of rapidly changing environments are investigated. Furthermore, relative priorities for ranking the targets are explicitly accommodated during the construction of potential tour sequences. As a consequence, a priori, as well as newly acquired, knowledge concerning the target objects enhances the potential value of the ultimate encounter sequences. A variety of transfer options are incorporated, from rendezvous arcs enabled by low-thrust engines to more conventional impulsive orbit adjustments via chemical propulsion technologies. When advantageous, trajectories are optimized in terms of propellant consumption via a combination of indirect and direct methods; such a combination of available technologies is an example of hybrid optimization. Additionally, elements of hybrid systems theory, i.e., the blending of dynamical states, some discrete and some continuous, are integrated into the high-level tour generation scheme. For a preliminary investigation, this strategy is applied to mission design scenarios for a Sun-Jupiter Trojan asteroid tour as well as orbital debris removal for near-Earth applications.

A Unified Global Reference Frame of Vertical Crustal Movements by Satellite Laser Ranging.

PubMed

Zhu, Xinhui; Wang, Ren; Sun, Fuping; Wang, Jinling

2016-02-08

Crustal movement is one of the main factors influencing the change of the Earth system, especially in its vertical direction, which affects people's daily life through the frequent occurrence of earthquakes, geological disasters, and so on. In order to get a better study and application of the vertical crustal movement,as well as its changes, the foundation and prerequisite areto devise and establish its reference frame; especially, a unified global reference frame is required. Since SLR (satellite laser ranging) is one of the most accurate space techniques for monitoring geocentric motion and can directly measure the ground station's geocentric coordinates and velocities relative to the centre of the Earth's mass, we proposed to take the vertical velocity of the SLR technique in the ITRF2008 framework as the reference frame of vertical crustal motion, which we defined as the SLR vertical reference frame (SVRF). The systematic bias between other velocity fields and the SVRF was resolved by using the GPS (Global Positioning System) and VLBI (very long baseline interferometry) velocity observations, and the unity of other velocity fields and SVRF was realized,as well. The results show that it is feasible and suitable to take the SVRF as a reference frame, which has both geophysical meanings and geodetic observations, so we recommend taking the SLR vertical velocity under ITRF2008 as the global reference frame of vertical crustal movement.

Station coordinates, baselines, and earth rotation from Lageos laser ranging - 1976-1984

NASA Technical Reports Server (NTRS)

Tapley, B. D.; Schultz, B. E.; Eanes, R. J.

1985-01-01

The orbit of the Lageos satellite is well suited as a reference frame for studying the rotation of the earth and the relative motion of points on the earth's crust. The satellite laser measurements can determine the location of a set of tracking stations in an appropriate terrestrial coordinate system. The motion of the earth's rotation axis relative to this system can be studied on the basis of the established tracking station locations. The present investigation is concerned with an analysis of 7.7 years of Lageos laser ranging data. In the first solution considered, the entire data span was used to adjust a single set of station positions simultaneously with orbit and earth rotation parameters. Attention is given to the accuracy of earth rotation parameters which are determined as an inherent part of the solution process.

Development of a special approach of the mineralization localization zones prediction based on the combination and the geoinformation analysis of heterogeneous geodata

NASA Astrophysics Data System (ADS)

Ivanova, Julia

2014-05-01

The complexity of any task solving, including tasks in the Earth Sciences, depends on the completeness of the information that is available. The prediction of the mineralization zone localization is a task with incomplete information. The tasks of prediction are complicated because of search data difficult formalize, and the absent of single information structures of the representation of the search data. These facts complicate the process of structuring, processing and analysis of information. Geodata that need to process are presented in various formats: raster two-dimensional and three-dimensional fields, vector layers of polygons and lines, point markable layers, the spectral and discrete, quantized and continuous, analog and digital forms, as well as chemical formalization. In this form representative data cannot be combining into superclasses. At the same time the information content of geodata that are applied individually is very small. While a number of low informative features, which can be obtained in the process of research of mineralization zones are usually redundant. As a result the quality of knowledge that can be obtained from the search data decreases, as well as the technological cycle of information processing increases. Additionally, that leads to exploitation of datasets, and production of large shared datasets [1]. To solve efficiently the tasks of predicting, it is necessary to use union heterogeneous search features, accumulated factual data and modern science-based mathematical apparatus of processing and analysis of the information. As well young branches of human knowledge help to solve this task: remote sensing, geoinformatics, Earth and Space Science Informatics [2], apparatus of catastrophe theory and nonlinear dynamics, game theory. The purpose of the suggested approach is to increase informational content, and to reduce of geodata redundancy to improve the accuracy of the prediction of mineralization zones. The developed algorithm of prediction of the localization of mineralization zone consists of the some steps: 1. The collection of information about the studying territory of upcoming work from various sources, i.e. building of database (DB). The DB includes variety geodata. 2. The formalization, the concatenation and the union of geodata. Study of features correlation characteristics. Generation of new formal and functional search features. 3. The formation of a number of hypotheses based on initial data. The refinement of search features. 4. Preliminary mathematical modeling of prospective mineralized zones. The study of obtained results, the formation of additional features list. 5. The collection of additional features by field methods for verifying of hypotheses. 6. Processing and analyzing of obtaining data, the specification of preliminary mathematical model. 7. The examination of hypotheses using the obtained results. The study of prediction errors. 8. Building of multidimensional risk matrices of detection and bifurcation diagrams of mineralization [3]. 9. The final mathematical modeling of perspective mineralized zones. Thus, the proposed approach allows to increase the information content of geodata significantly, to reduce redundancy of geodate, and to increase the accuracy of predicting zones of gold mineralization. Currently the approach, suggested by the author, applies for prediction of the localization of gold mineralization at the territory of the Polar Urals. References: 1.W. J. Som de Cerff, M. Petitdidier, A. Gemünd, L. Horstink, H. Schwichtenberg, Earth Science Test Suites to Evaluate Grid Tools and Middleware-Examples for Grid Data Access Tools, Earth Science Informatics, Vol. 2, 117-131, 2009. DOI 10.1007/s12145-009-0022-y. 2. P. Mazzetti , S. Nativi, J. Caron, RESTfulI implementation of Geospatial, Services for Earth and Space Science Applications, International Journal of Digital Earth, Vol. 2, Supplement 1, 40-61, 2009. DOI: 10.1080/175389409028661532. 3. Arnold V.I., Catastrophe Theory, 4th ed. Moscow, Editorial-URSS (2004), ISBN 5-354-00674-0 (in Russian).

Basic Geometric Support of Systems for Earth Observation from Geostationary and Highly Elliptical Orbits

NASA Astrophysics Data System (ADS)

Gektin, Yu. M.; Egoshkin, N. A.; Eremeev, V. V.; Kuznecov, A. E.; Moskatinyev, I. V.; Smelyanskiy, M. B.

2017-12-01

A set of standardized models and algorithms for geometric normalization and georeferencing images from geostationary and highly elliptical Earth observation systems is considered. The algorithms can process information from modern scanning multispectral sensors with two-coordinate scanning and represent normalized images in optimal projection. Problems of the high-precision ground calibration of the imaging equipment using reference objects, as well as issues of the flight calibration and refinement of geometric models using the absolute and relative reference points, are considered. Practical testing of the models, algorithms, and technologies is performed in the calibration of sensors for spacecrafts of the Electro-L series and during the simulation of the Arktika prospective system.

An Automated Method for Navigation Assessment for Earth Survey Sensors Using Island Targets

NASA Technical Reports Server (NTRS)

Patt, F. S.; Woodward, R. H.; Gregg, W. W.

1997-01-01

An automated method has been developed for performing navigation assessment on satellite-based Earth sensor data. The method utilizes islands as targets which can be readily located in the sensor data and identified with reference locations. The essential elements are an algorithm for classifying the sensor data according to source, a reference catalogue of island locations, and a robust pattern-matching algorithm for island identification. The algorithms were developed and tested for the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), an ocean colour sensor. This method will allow navigation error statistics to be automatically generated for large numbers of points, supporting analysis over large spatial and temporal ranges.

Automated navigation assessment for earth survey sensors using island targets

NASA Technical Reports Server (NTRS)

Patt, Frederick S.; Woodward, Robert H.; Gregg, Watson W.

1997-01-01

An automated method has been developed for performing navigation assessment on satellite-based Earth sensor data. The method utilizes islands as targets which can be readily located in the sensor data and identified with reference locations. The essential elements are an algorithm for classifying the sensor data according to source, a reference catalog of island locations, and a robust pattern-matching algorithm for island identification. The algorithms were developed and tested for the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), an ocean color sensor. This method will allow navigation error statistics to be automatically generated for large numbers of points, supporting analysis over large spatial and temporal ranges.

A simple demonstration when studying the equivalence principle

NASA Astrophysics Data System (ADS)

Mayer, Valery; Varaksina, Ekaterina

2016-06-01

The paper proposes a lecture experiment that can be demonstrated when studying the equivalence principle formulated by Albert Einstein. The demonstration consists of creating stroboscopic photographs of a ball moving along a parabola in Earth's gravitational field. In the first experiment, a camera is stationary relative to Earth's surface. In the second, the camera falls freely downwards with the ball, allowing students to see that the ball moves uniformly and rectilinearly relative to the frame of reference of the freely falling camera. The equivalence principle explains this result, as it is always possible to propose an inertial frame of reference for a small region of a gravitational field, where space-time effects of curvature are negligible.

Low-cost Tools for Aerial Video Geolocation and Air Traffic Analysis for Delay Reduction Using Google Earth

NASA Astrophysics Data System (ADS)

Zetterlind, V.; Pledgie, S.

2009-12-01

Low-cost, low-latency, robust geolocation and display of aerial video is a common need for a wide range of earth observing as well as emergency response and security applications. While hardware costs for aerial video collection systems, GPS, and inertial sensors have been decreasing, software costs for geolocation algorithms and reference imagery/DTED remain expensive and highly proprietary. As part of a Federal Small Business Innovative Research project, MosaicATM and EarthNC, Inc have developed a simple geolocation system based on the Google Earth API and Google's 'built-in' DTED and reference imagery libraries. This system geolocates aerial video based on platform and camera position, attitude, and field-of-view metadata using geometric photogrammetric principles of ray-intersection with DTED. Geolocated video can be directly rectified and viewed in the Google Earth API during processing. Work is underway to extend our geolocation code to NASA World Wind for additional flexibility and a fully open-source platform. In addition to our airborne remote sensing work, MosaicATM has developed the Surface Operations Data Analysis and Adaptation (SODAA) tool, funded by NASA Ames, which supports analysis of airport surface operations to optimize aircraft movements and reduce fuel burn and delays. As part of SODAA, MosaicATM and EarthNC, Inc have developed powerful tools to display national airspace data and time-animated 3D flight tracks in Google Earth for 4D analysis. The SODAA tool can convert raw format flight track data, FAA National Flight Data (NFD), and FAA 'Adaptation' airport surface data to a spatial database representation and then to Google Earth KML. The SODAA client provides users with a simple graphical interface through which to generate queries with a wide range of predefined and custom filters, plot results, and export for playback in Google Earth in conjunction with NFD and Adaptation overlays.

The Earth Gravitational Model 1996: The NCCS: Resource for Development, Resource for the Future

NASA Technical Reports Server (NTRS)

2002-01-01

For centuries, men have attempted to understand the climate system through observations obtained from Earth's surface. These observations yielded preliminary understanding of the ocean currents, tides, and prevailing winds using visual observation and simple mechanical tools as their instruments. Today's sensitive, downward-looking radar systems, called altimeters, onboard satellites can measure globally the precise height of the ocean surface. This surface is largely that of the equipotential gravity surface, called the geoid - the level surface to which the oceans would conform if there were no forces acting on them apart from gravity, as well as having a significant 1-2- meter-level signal arising from the motion of the ocean's currents.

Design Study of 8 Meter Monolithic Mirror UV/Optical Space Telescope

NASA Technical Reports Server (NTRS)

Stahl, H. Philip

2008-01-01

The planned Ares V launch vehicle with its 10 meter fairing shroud and 55,000 kg capacity to the Sun Earth L2 point enables entirely new classes of space telescopes. NASA MSFC has conducted a preliminary study that demonstrates the feasibility of launching a 6 to 8 meter class monolithic primary mirror telescope to Sun-Earth L2 using an Ares V. Specific technical areas studied included optical design; structural design/analysis including primary mirror support structure, sun shade and secondary mirror support structure; thermal analysis; launch vehicle performance and trajectory; spacecraft including structure, propulsion, GN&C, avionics, power systems and reaction wheels; operations and servicing; mass and power budgets; and system cost.

Very high numerical aperture light transmitting device

DOEpatents

Allison, Stephen W.; Boatner, Lynn A.; Sales, Brian C.

1998-01-01

A new light-transmitting device using a SCIN glass core and a novel calcium sodium cladding has been developed. The very high index of refraction, radiation hardness, similar solubility for rare earths and similar melt and viscosity characteristics of core and cladding materials makes them attractive for several applications such as high-numerical-aperture optical fibers and specialty lenses. Optical fibers up to 60 m in length have been drawn, and several simple lenses have been designed, ground, and polished. Preliminary results on the ability to directly cast optical components of lead-indium phosphate glass are also discussed as well as the suitability of these glasses as a host medium for rare-earth ion lasers and amplifiers.

Preliminary characterization of persisting circadian rhythms during space flight

NASA Technical Reports Server (NTRS)

Sultzman, F. M.

1984-01-01

In order to evaluate the function of the circadian timing system in space, the circadian rhythm of conidiation of the fungus Neurospora crassa was monitored in constant darkness on the STS 9 flight of the Space Shuttle Columbia. During the first 7 days of spaceflight many tubes showed a marked reduction in the apparent amplitude of the conidiation rhythm, and some cultures appeared arrhythmic. There was more variability in the growth rate and circadian rhythms of individual cultures in space than is usually seen on earth. The results of this experiment indicate that while the circadian rhythm of Neurospora conidiation can persist outside of the earth's environment, either the timekeeping process or its expression is altered in space.

Performance Evaluation of the Geostationary Synthetic Thinned Array Radiometer (GeoSTAR) Demonstrator Instrument

NASA Technical Reports Server (NTRS)

Tanner, Alan B.; Wilson, William J.; Lambrigsten, Bjorn H.; Dinardo, Steven J.; Brown, Shannon T.; Kangaslahti, Pekka P.; Gaier, Todd C.; Ruf, C. S.; Gross, S. M.; Lim, B. H.;

Cometary Amino Acids from the STARDUST Mission

NASA Technical Reports Server (NTRS)

Cook, Jamie Elsila

2009-01-01

NASA's Stardust spacecraft returned samples from comet 81 P/WiId 2 to Earth in January 2006. Examinations of the organic compounds in cometary samples can reveal information about the prebiotic organic inventory present on the early Earth and within the early Solar System, which may have contributed to the origin of life. Preliminary studies of Stardust material revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds (cometary vs. terrestrial contamination) could not be identified. We have recently measured the carbon isotopic ratios of these amino acids to determine their origin, leading to the first detection of a cometary amino acid.

The Development and Status of Earth Science Education: A Comparison of Three Case Studies: Israel, England and Wales and the United States of America. Part II.

ERIC Educational Resources Information Center

Orion, Nir; King, Chris; Krockover, Gerald H.; Adams, Paul E.

1999-01-01

Explores the development and status of earth-science education in the United States. Compares the U.S. case with those of Israel, England, and Wales. Discusses the need to share common concerns and visions between cultures and communities. Contains 45 references. (Author/WRM)

A Sun-Earth-Moon Activity to Develop Student Understanding of Lunar Phases and Frames of Reference

ERIC Educational Resources Information Center

Ashmann, Scott

2012-01-01

The Moon is an ever-present subject of observation, and it is a recurring topic in the science curriculum from kindergarten's basic observations through graduate courses' mathematical analyses of its orbit. How do students come to comprehend Earth's nearest neighbor? What is needed for them to understand the lunar phases and other phenomena and…

Projectiles, pendula, and special relativity

NASA Astrophysics Data System (ADS)

Price, Richard H.

2005-05-01

The kind of flat-earth gravity used in introductory physics appears in an accelerated reference system in special relativity. From this viewpoint, we work out the special relativistic description of a ballistic projectile and a simple pendulum, two examples of simple motion driven by earth-surface gravity. The analysis uses only the basic mathematical tools of special relativity typical of a first-year university course.

My Patch of Earth: Using the Schoolground as a Teaching and Learning Referent for an Environmental Ethic.

ERIC Educational Resources Information Center

Smit, Nel

The schoolground is a small and vital piece of earth--a microcosm of a diverse and sustaining world. Promoting an environmental ethic in this location is a challenging opportunity for educators. This paper shows that natural places in schoolgrounds can provide the venue for exciting and ongoing teaching and learning opportunities in this outdoor…

Assessment of the Spectral Stability of Libya 4, Libya 1, and Mauritania 2 Sites Using Earth Observing One Hyperion

NASA Technical Reports Server (NTRS)

Choi, Taeyoung; Xiong, Xiaoxiong; Angal, Amit; Chander, Gyanesh; Qu, John J.

2014-01-01

The objective of this paper is to formulate a methodology to assess the spectral stability of the Libya 4, Libya 1, and Mauritania 2 pseudo-invariant calibration sites (PICS) using Earth Observing One (EO-1) Hyperion sensor. All the available Hyperion collections, downloaded from the Earth Explorer website, were utilized for the three PICS. In each site, a reference spectrum is selected at a specific day in the vicinity of the region of interest (ROI) defined by Committee on Earth Observation Satellites (CEOS). A series of ROIs are predefined in the along-track direction with 196 spectral top-of-atmosphere reflectance values in each ROI. Based on the reference ROI spectrum, the spectral stability of these ROIs is evaluated by average deviations (ADs) and spectral angle mapper (SAM) methods in the specific ranges of time and geo-spatial locations. Time and ROI location-dependent SAM and AD results are very stable within +/- 2 deg and +/-1.7% of 1sigma standard deviations. Consequently, the Libya 4, Mauritania 2, and Libya 1 CEOS selected PICS are spectrally stable targets within the time and spatial swath ranges of the Hyperion collections.

To Live on Earth. Man and His Environment in Perspective.

ERIC Educational Resources Information Center

Brubaker, Sterling

In this text, written for the general reader rather than for the specialist, the accelerating use of man's environment is considered from agricultural, economic, demographic, and land and other resource use, with principal reference to the United States situation, but with reference to the world scale when appropriate. Environmental threats are…

Automated iodine monitor system. [for aqueous solutions

NASA Technical Reports Server (NTRS)

1973-01-01

The feasibility of a direct spectrophotometric measurement of iodine in water was established. An iodine colorimeter, was built to demonstrate the practicality of this technique. The specificity of this method was verified when applied to an on-line system where a reference solution cannot be used, and a preliminary design is presented for an automated iodine measuring and controlling system meeting the desired specifications. An Automated iodine monitor/controller system based on this preliminary design was built, tested, and delivered to the Johnson Space Center.

The consistency of the current conventional celestial and terrestrial reference frames and the conventional EOP series

NASA Astrophysics Data System (ADS)

Heinkelmann, R.; Belda-Palazon, S.; Ferrándiz, J.; Schuh, H.

2015-08-01

For applications in Earth sciences, navigation, and astronomy the celestial (ICRF) and terrestrial (ITRF) reference frames as well as the orientation among them, the Earth orientation parameters (EOP), have to be consistent at the level of 1 mm and 0.1 mm/yr (GGOS recommendations). We assess the effect of unmodelled geophysical signals in the regularized coordinates and the sensitivity with respect to different a priori EOP and celestial reference frames. The EOP are determined using the same VLBI data but with station coordinates fixed on different TRFs. The conclusion is that within the time span of data incorporated into ITRF2008 (Altamimi, et al., 2011) the ITRF2008 and the IERS 08 C04 are consistent. This consistency involves that non-linear station motion such as unmodelled geophysical signals partly affect the IERS 08 C04 EOP. There are small but not negligible inconsistencies between the conventional celestial reference frame, ICRF2 (Fey, et al., 2009), the ITRF2008 and the conventional EOP that are quantified by comparing VTRF2008 (Böckmann, et al., 2010) and ITRF2008.

Program for integrating multizonal photographs of the Earth, taken by MKF-6 camera, in a computer

NASA Technical Reports Server (NTRS)

Agapov, A. V.; Mosin, S. T.

1980-01-01

An algorithm and program are described, for integrating up to 6 simultaneously exposed photographs in different spectral ranges of the surface of the Earth, taken by MKF-6 cameras aboard Soyuz-22. Three of the reference marks are identified on 1 photograph and then are used to integrate the other photographs with the first. The program was compiled for the ES-1040 computer, as a standard subprogram in a system for computer processing of data of study of the Earth from space.

Development, Deployment, and Assessment of Dynamic Geological and Geophysical Models Using the Google Earth APP and API: Implications for Undergraduate Education in the Earth and Planetary Sciences

NASA Astrophysics Data System (ADS)

de Paor, D. G.; Whitmeyer, S. J.; Gobert, J.

2009-12-01

We previously reported on innovative techniques for presenting data on virtual globes such as Google Earth using emergent Collada models that reveal subsurface geology and geophysics. We here present several new and enhanced models and linked lesson plans to aid deployment in undergraduate geoscience courses, along with preliminary results from our assessment of their effectiveness. The new Collada models are created with Google SketchUp, Bonzai3D, and MeshLab software, and are grouped to cover (i) small scale field mapping areas; (ii) regional scale studies of the North Atlantic Ocean Basin, the Appalachian Orogen, and the Pacific Ring of Fire; and (iii) global scale studies of terrestrial planets, moons, and asteroids. Enhancements include emergent block models with three-dimensional surface topography; models that conserve structural orientation data; interactive virtual specimens; models that animate plate movements on the virtual globe; exploded 3-D views of planetary mantles and cores; and server-generated dynamic KML. We tested volunteer students and professors using Silverback monitoring software, think-aloud verbalizations, and questionnaires designed to assess their understanding of the underlying geo-scientific phenomena. With the aid of a cohort of instructors across the U.S., we are continuing to assess areas in which users encounter difficulties with both the software and geoscientific concepts. Preliminary results suggest that it is easy to overestimate the computer expertise of novice users even when they are content knowledge experts (i.e., instructors), and that a detailed introduction to virtual globe manipulation is essential before moving on to geoscience applications. Tasks that seem trivial to developers may present barriers to non-technical users and technicalities that challenge instructors may block adoption in the classroom. We have developed new models using the Google Earth API which permits enhanced interaction and dynamic feedback and are assessing their relative merits versus the Google Earth APP. Overall, test students and professors value the models very highly. There are clear pedagogical opportunities for using materials such as these to create engaging in-course research opportunities for undergraduates.

TPS design for aerobraking at Earth and Mars

NASA Astrophysics Data System (ADS)

Williams, S. D.; Gietzel, M. M.; Rochelle, W. C.; Curry, D. M.

1991-08-01

An investigation was made to determine the feasibility of using an aerobrake system for manned and unmanned missions to Mars, and to Earth from Mars and lunar orbits. A preliminary thermal protection system (TPS) was examined for five unmanned small nose radius, straight bi-conic vehicles and a scaled up Aeroassist Flight Experiment (AFE) vehicle aerocapturing at Mars. Analyses were also conducted for the scaled up AFE and an unmanned Sample Return Cannister (SRC) returning from Mars and aerocapturing into Earth orbit. Also analyzed were three different classes of lunar transfer vehicles (LTV's): an expendable scaled up modified Apollo Command Module (CM), a raked cone (modified AFT), and three large nose radius domed cylinders. The LTV's would be used to transport personnel and supplies between Earth and the moon in order to establish a manned base on the lunar surface. The TPS for all vehicles analyzed is shown to have an advantage over an all-propulsive velocity reduction for orbit insertion. Results indicate that TPS weight penalties of less than 28 percent can be achieved using current material technology, and slightly less than the most favorable LTV using advanced material technology.

A Novel Grid SINS/DVL Integrated Navigation Algorithm for Marine Application

PubMed Central

Kang, Yingyao; Zhao, Lin; Cheng, Jianhua; Fan, Xiaoliang

2018-01-01

Integrated navigation algorithms under the grid frame have been proposed based on the Kalman filter (KF) to solve the problem of navigation in some special regions. However, in the existing study of grid strapdown inertial navigation system (SINS)/Doppler velocity log (DVL) integrated navigation algorithms, the Earth models of the filter dynamic model and the SINS mechanization are not unified. Besides, traditional integrated systems with the KF based correction scheme are susceptible to measurement errors, which would decrease the accuracy and robustness of the system. In this paper, an adaptive robust Kalman filter (ARKF) based hybrid-correction grid SINS/DVL integrated navigation algorithm is designed with the unified reference ellipsoid Earth model to improve the navigation accuracy in middle-high latitude regions for marine application. Firstly, to unify the Earth models, the mechanization of grid SINS is introduced and the error equations are derived based on the same reference ellipsoid Earth model. Then, a more accurate grid SINS/DVL filter model is designed according to the new error equations. Finally, a hybrid-correction scheme based on the ARKF is proposed to resist the effect of measurement errors. Simulation and experiment results show that, compared with the traditional algorithms, the proposed navigation algorithm can effectively improve the navigation performance in middle-high latitude regions by the unified Earth models and the ARKF based hybrid-correction scheme. PMID:29373549

Observation of the Earth liquid core resonance by extensometers

NASA Astrophysics Data System (ADS)

Bán, Dóra; Mentes, Gyula

2016-04-01

The axis of the fluid outer core of the Earth and the rotation axis of the mantle do not coincide therefore restoring forces are set up at the core-mantle boundary which try to realign the two axes causing a resonance effect. In celestial reference system it is called the "Free Core Nutation" (FCN), which can be characterized by a period of 432 days while in the Earth reference system it is called the "Nearly Diurnal Free Wobble" (NDFW). The frequency of this phenomenon is near to the diurnal tidal frequencies, especially to P1 and K1 waves. Due to its resonance effect this phenomenon can be detected also by quartz tube extensometers suitable for Earth tides recording. In this study data series measured in several extensometric stations were used to reveal the presence of the FCN resonance. In the Pannonian Basin there are five observatories where extensometric measurements were carried out in different lengths of time. Four stations in Hungary: Sopronbánfalva Geodynamical Observatory (2000-2014), Budapest Mátyáshegy Gravity and Geodynamic Observatory (2005-2012), Pécs uranium mine (1991-1999), Bakonya, near to Pécs (2004-2005) and in Slovakia: Vyhne Earth Tide Observatory (2001-2013). Identical instrumentation in different observatories provides the opportunity to compare measurements with various topography, geology and environmental parameters. The results are also compared to values inferred from extensometric measurements in other stations.

Deep mantle structure as a reference frame for movements in and on the Earth.

PubMed

Torsvik, Trond H; van der Voo, Rob; Doubrovine, Pavel V; Burke, Kevin; Steinberger, Bernhard; Ashwal, Lewis D; Trønnes, Reidar G; Webb, Susan J; Bull, Abigail L

2014-06-17

Earth's residual geoid is dominated by a degree-2 mode, with elevated regions above large low shear-wave velocity provinces on the core-mantle boundary beneath Africa and the Pacific. The edges of these deep mantle bodies, when projected radially to the Earth's surface, correlate with the reconstructed positions of large igneous provinces and kimberlites since Pangea formed about 320 million years ago. Using this surface-to-core-mantle boundary correlation to locate continents in longitude and a novel iterative approach for defining a paleomagnetic reference frame corrected for true polar wander, we have developed a model for absolute plate motion back to earliest Paleozoic time (540 Ma). For the Paleozoic, we have identified six phases of slow, oscillatory true polar wander during which the Earth's axis of minimum moment of inertia was similar to that of Mesozoic times. The rates of Paleozoic true polar wander (<1°/My) are compatible with those in the Mesozoic, but absolute plate velocities are, on average, twice as high. Our reconstructions generate geologically plausible scenarios, with large igneous provinces and kimberlites sourced from the margins of the large low shear-wave velocity provinces, as in Mesozoic and Cenozoic times. This absolute kinematic model suggests that a degree-2 convection mode within the Earth's mantle may have operated throughout the entire Phanerozoic.

Detecting and connecting agricultural ditches using LiDAR data

NASA Astrophysics Data System (ADS)

Roelens, Jennifer; Dondeyne, Stefaan; Van Orshoven, Jos; Diels, Jan

2017-04-01

High-resolution hydrological data are essential for spatially-targeted water resource management decisions and future modelling efforts. For Flanders, small water courses like agricultural ditches and their connection to the river network are incomplete in the official digital atlas. High-resolution LiDAR data offer the prospect for automated detection of ditches, but there is no established method or software to do so nor to predict how these are connected to each other and the wider hydrographic network. An aerial LiDAR database encompassing at least 16 points per square meter linked with simultaneously collected digital RGB aerial images, is available for Flanders. The potential of detecting agricultural ditches and their connectivity based on point LiDAR data was investigated in a 1.9 km2 study area located in the alluvial valley of the river Demer. The area consists of agricultural parcels and woodland with a ditch network of approximately 17 km. The entire network of open ditches, and the location of culverts were mapped during a field survey to test the effectiveness of the proposed method. In the first step of the proposed method, the LiDAR point data were transformed into a raster DEM with a 1-m resolution to reduce the amount of data to be analyzed. This was done by interpolating the bare earth points using the nearest neighborhood method. In a next step, a morphological approach was used for detecting a preliminary network as traditional flow algorithms are not suitable for detecting small water courses in low-lying areas. This resulted in a preliminary classified raster image with ditch and non-ditch cells. After eliminating small details that are the result of background noise, the resulting classified raster image was vectorized to match the format of the digital watercourse network. As the vectorisation does not always adequately represent the shape of linear features, the results did not meet the high-quality cartographic needs. The spatial accuracy of the derived ditches was improved by referring to the original LiDAR point cloud data. In each 1-m buffer of the preliminary detected network vertices, the lowest LiDAR point was taken as the vertex of an improved network, shifting the preliminary network into the lowest 'depressions' of the study area. A drawback of a morphological approach is that the connectivity of the network is usually poor since the pixels are processed separately. Therefore, the field observations on connectivity (including culverts) were used to develop an empirical model to estimate the probability of connectivity between LiDAR-derived ditch segments from auxiliary datasets and hydrological and morphological properties of the preliminary network. This allowed deriving a connectivity probability map. The underlying model was tested by cross-validating the field observations on connectivity.

The Orbiter camera payload system's large-format camera and attitude reference system

NASA Technical Reports Server (NTRS)

Schardt, B. B.; Mollberg, B. H.

1985-01-01

The Orbiter camera payload system (OCPS) is an integrated photographic system carried into earth orbit as a payload in the Space Transportation System (STS) Orbiter vehicle's cargo bay. The major component of the OCPS is a large-format camera (LFC), a precision wide-angle cartographic instrument capable of producing high-resolution stereophotography of great geometric fidelity in multiple base-to-height ratios. A secondary and supporting system to the LFC is the attitude reference system (ARS), a dual-lens stellar camera array (SCA) and camera support structure. The SCA is a 70 mm film system that is rigidly mounted to the LFC lens support structure and, through the simultaneous acquisition of two star fields with each earth viewing LFC frame, makes it possible to precisely determine the pointing of the LFC optical axis with reference to the earth nadir point. Other components complete the current OCPS configuration as a high-precision cartographic data acquisition system. The primary design objective for the OCPS was to maximize system performance characteristics while maintaining a high level of reliability compatible with rocket launch conditions and the on-orbit environment. The full OCPS configuration was launched on a highly successful maiden voyage aboard the STS Orbiter vehicle Challenger on Oct. 5, 1984, as a major payload aboard the STS-41G mission.

Spatial patterns of (137)Cs inventories and soil erosion from earth-banked terraces in the Yimeng Mountains, China.

PubMed

Zhang, Yunqi; Long, Yi; An, Juan; Yu, Xingxiu; Wang, Xiaoli

2014-10-01

The Yimeng Mountains is one of China's most susceptible regions to soil erosion. In this region, slopes are composed of granite- or gneiss-derived soils that are commonly cultivated using earth-banked terraces. Based on the (137)Cs measurement for nine reference cores, the present study analysed the spatial patterns of (137)Cs inventory and soil erosion using 105 sampling points in a seven-level earth-banked terrace system. The mean (137)Cs inventory, standard deviation, coefficient of variation, and allowable error for the nine reference cores were 987 Bq m(-2), 71 Bq m(-2), 7%, and 6%, respectively, values that may reflect the heterogeneity of the initial (137)Cs fallout deposit. Within each terrace, the (137)Cs inventory generally increases from the rear edge to the front edge, accompanied by a decrease in the erosion rate. This results from planation by tillage and rainfall runoff during the development of the earth-banked terraces. Across the entire seven-level terrace system, (137)Cs inventories decrease from the highest terrace downwards, but increase in the lower terraces, whereas erosion rate displays the opposite trend. These trends are the result of the combined effects of the earth-bank segmented hillslope, the limited protection of the earth banks, and rainfall runoff in combination with tillage. The high coefficients of variation of (137)Cs inventories for the 21 sampling rows, with a mean value of 44%, demonstrate the combined effects of variations in original microtopography, anthropogenic disturbance, the incohesive soils weathered from underlying granite, and the warm climate. Although earth-banked terraces can reduce soil erosion to some extent, the estimated erosion rates for the study area are still very high. Copyright © 2014 Elsevier Ltd. All rights reserved.

Novel approach in k0-NAA for highly concentrated REE Samples.

PubMed

Abdollahi Neisiani, M; Latifi, M; Chaouki, J; Chilian, C

2018-04-01

The present paper presents a new approach for k 0 -NAA for accurate quantification with short turnaround analysis times for rare earth elements (REEs) in high content mineral matrices. REE k 0 and Q 0 values, spectral interferences and nuclear interferences were experimentally evaluated and improved with Alfa Aesar Specpure Plasma Standard 1000mgkg -1 mono-rare earth solutions. The new iterative gamma-ray self-attenuation and neutron self-shielding methods were investigated with powder standards prepared from 100mg of 99.9% Alfa Aesar mono rare earth oxide diluted with silica oxide. The overall performance of the new k 0 -NAA method for REEs was validated using a certified reference material (CRM) from Canadian Certified Reference Materials Project (REE-2) with REE content ranging from 7.2mgkg -1 for Yb to 9610mgkg -1 for Ce. The REE concentration was determined with uncertainty below 7% (at 95% confidence level) and proved good consistency with the CRM certified concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing rare earth elements in quartz rich geological samples.

PubMed

Santoro, A; Thoss, V; Ribeiro Guevara, S; Urgast, D; Raab, A; Mastrolitti, S; Feldmann, J

2016-01-01

Sodium peroxide (Na2O2) fusion coupled to Inductively Coupled Plasma Tandem Mass Spectrometry (ICP-MS/MS) measurements was used to rapidly screen quartz-rich geological samples for rare earth element (REE) content. The method accuracy was checked with a geological reference material and Instrumental Neutron Activation Analysis (INAA) measurements. The used mass-mode combinations presented accurate results (only exception being (157)Gd in He gas mode) with recovery of the geological reference material QLO-1 between 80% and 98% (lower values for Lu, Nd and Sm) and in general comparable to INAA measurements. Low limits of detection for all elements were achieved, generally below 10 pg g(-1), as well as measurement repeatability below 15%. Overall, the Na2O2/ICP-MS/MS method proved to be a suitable lab-based method to quickly and accurately screen rock samples originating from quartz-rich geological areas for rare earth element content; particularly useful if checking commercial viability. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preliminary Evaluation of the Multipurpose Arcade Combat Simulator (MACS) for the M16, M203, and M72A2

DTIC Science & Technology

1985-06-01

8217 .. = . . - , . . ’ ’ ’- . .’- ’, . -. . ’ -. . . .- . -. .. .. - . . % , -. . REFERENCES * Belier , F. H., Thompson, T. J., &Osborne, A. D. (Draft, 1981). Basic rifle marksmanship

Calibrating Historical IR Sensors Using GEO, and AVHRR Infrared Tropical Mean Calibration Models

NASA Technical Reports Server (NTRS)

Scarino, Benjamin; Doelling, David R.; Minnis, Patrick; Gopalan, Arun; Haney, Conor; Bhatt, Rajendra

2014-01-01

Long-term, remote-sensing-based climate data records (CDRs) are highly dependent on having consistent, wellcalibrated satellite instrument measurements of the Earth's radiant energy. Therefore, by making historical satellite calibrations consistent with those of today's imagers, the Earth-observing community can benefit from a CDR that spans a minimum of 30 years. Most operational meteorological satellites rely on an onboard blackbody and space looks to provide on-orbit IR calibration, but neither target is traceable to absolute standards. The IR channels can also be affected by ice on the detector window, angle dependency of the scan mirror emissivity, stray-light, and detector-to-detector striping. Being able to quantify and correct such degradations would mean IR data from any satellite imager could contribute to a CDR. Recent efforts have focused on utilizing well-calibrated modern hyper-spectral sensors to intercalibrate concurrent operational IR imagers to a single reference. In order to consistently calibrate both historical and current IR imagers to the same reference, however, another strategy is needed. Large, well-characterized tropical-domain Earth targets have the potential of providing an Earth-view reference accuracy of within 0.5 K. To that effort, NASA Langley is developing an IR tropical mean calibration model in order to calibrate historical Advanced Very High Resolution Radiometer (AVHRR) instruments. Using Meteosat-9 (Met-9) as a reference, empirical models are built based on spatially/temporally binned Met-9 and AVHRR tropical IR brightness temperatures. By demonstrating the stability of the Met-9 tropical models, NOAA-18 AVHRR can be calibrated to Met-9 by matching the AVHRR monthly histogram averages with the Met-9 model. This method is validated with ray-matched AVHRR and Met-9 biasdifference time series. Establishing the validity of this empirical model will allow for the calibration of historical AVHRR sensors to within 0.5 K, and thereby establish a climate-quality IR data record.

Project MANTIS: A MANTle Induction Simulator for coupling geodynamic and electromagnetic modeling

NASA Astrophysics Data System (ADS)

Weiss, C. J.

2009-12-01

A key component to testing geodynamic hypotheses resulting from the 3D mantle convection simulations is the ability to easily translate the predicted physiochemical state to the model space relevant for an independent geophysical observation, such as earth's seismic, geodetic or electromagnetic response. In this contribution a new parallel code for simulating low-frequency, global-scale electromagnetic induction phenomena is introduced that has the same Earth discretization as the popular CitcomS mantle convection code. Hence, projection of the CitcomS model into the model space of electrical conductivity is greatly simplified, and focuses solely on the node-to-node, physics-based relationship between these Earth parameters without the need for "upscaling", "downscaling", averaging or harmonizing with some other model basis such as spherical harmonics. Preliminary performance tests of the MANTIS code on shared and distributed memory parallel compute platforms shows favorable scaling (>70% efficiency) for up to 500 processors. As with CitcomS, an OpenDX visualization widget (VISMAN) is also provided for 3D rendering and interactive interrogation of model results. Details of the MANTIS code will be briefly discussed here, focusing on compatibility with CitcomS modeling, as will be preliminary results in which the electromagnetic response of a CitcomS model is evaluated. VISMAN rendering of electrical tomography-derived electrical conductivity model overlain by an a 1x1 deg crustal conductivity map. Grey scale represents the log_10 magnitude of conductivity [S/m]. Arrows are horiztonal components of a hypothetical magnetospheric source field used to electromagnetically excite the conductivity model.

Characteristics of Medical Research News Reported on Front Pages of Newspapers

PubMed Central

Lai, William Yuk Yeu; Lane, Trevor

2009-01-01

Background The placement of medical research news on a newspaper's front page is intended to gain the public's attention, so it is important to understand the source of the news in terms of research maturity and evidence level. Methodology/Principal Findings We searched LexisNexis to identify medical research reported on front pages of major newspapers published from January 1, 2000 to December 31, 2002. We used MEDLINE and Google Scholar to find journal articles corresponding to the research, and determined their evidence level. Of 734 front-page medical research stories identified, 417 (57%) referred to mature research published in peer-reviewed journals. The remaining 317 stories referred to preliminary findings presented at scientific or press meetings; 144 (45%) of those stories mentioned studies that later matured (i.e. were published in journals within 3 years after news coverage). The evidence-level distribution of the 515 journal articles quoted in news stories reporting on mature research (3% level I, 21% level II, 42% level III, 4% level IV, and 31% level V) differed from that of the 170 reports of preliminary research that later matured (1%, 19%, 35%, 12%, and 33%, respectively; chi-square test, P = .0009). No news stories indicated evidence level. Fewer than 1 in 5 news stories reporting preliminary findings acknowledged the preliminary nature of their content. Conclusions/Significance Only 57% of front-page stories reporting on medical research are based on mature research, which tends to have a higher evidence level than research with preliminary findings. Medical research news should be clearly referenced and state the evidence level and limitations to inform the public of the maturity and quality of the source. PMID:19568422

Abort Options for Human Lunar Missions between Earth Orbit and Lunar Vicinity

NASA Technical Reports Server (NTRS)

Condon, Gerald L.; Senent, Juan S.; Llama, Eduardo Garcia

2005-01-01

Apollo mission design emphasized operational flexibility that supported premature return to Earth. However, that design was tailored to use expendable hardware for short expeditions to low-latitude sites and cannot be applied directly to an evolutionary program requiring long stay times at arbitrary sites. This work establishes abort performanc e requirements for representative onorbit phases of missions involvin g rendezvous in lunar-orbit, lunar-surface and at the Earth-Moon libr ation point. This study submits reference abort delta-V requirements and other Earth return data (e.g., entry speed, flight path angle) and also examines the effect of abort performance requirements on propul sive capability for selected vehicle configurations.

Preliminary design of the thermal protection system for solar probe

NASA Technical Reports Server (NTRS)

Dirling, R. B., Jr.; Loomis, W. C.; Heightland, C. N.

1982-01-01

A preliminary design of the thermal protection system for the NASA Solar Probe spacecraft is presented. As presently conceived, the spacecraft will be launched by the Space Shuttle on a Jovian swing-by trajectory and at perihelion approach to three solar radii of the surface of the Earth's sun. The system design satisfies maximum envelope, structural integrity, equipotential, and mass loss/contamination requirements by employing lightweight carbon-carbon emissive shields. The primary shield is a thin shell, 15.5-deg half-angle cone which absorbs direct solar flux at up to 10-deg off-nadir spacecraft pointing angles. Secondary shields of sandwich construction and low thickness-direction thermal conductivity are used to reduce the primary shield infrared radiation to the spacecraft payload.

Preliminary design study. Shuttle modular scanning spectroradiometer

NASA Technical Reports Server (NTRS)

1975-01-01

Fundamental concepts on which to base a detailed design for a Shuttle Modular Scanning Spectroradiometer were developed, and a preliminary design is presented. The recommended design features modularity and flexibility. It includes a 75-cm f/1.7-telescope assembly in an all-reflective Schmidt configuration, a solid state scan system (pushbroom) with high resolution over a 15 deg field of view, and ten detector channels covering the spectral range from 0.45 to 12.5 micrometers. It uses charge transfer device techniques to accommodate a large number of detector elements for earth observation measurements. Methods for in-flight radiometric calibration, for image motion compensation, and for data processing are described. Recommendations for ground support equipment are included, and interfaces with the shuttle orbiter vehicle are illustrated.

Apollo 17 traverse gravimeter experiment /Preliminary results/

NASA Technical Reports Server (NTRS)

Talwani, M.; Kahle, H.-G.

1976-01-01

Preliminary results of the traverse gravimeter experiment successfully performed during the Apollo 17 mission are discussed. An earth-moon gravity tie was established. On the basis of several readings, a gravity value of 162,695 + or - 5 mgal was obtained at the lunar-module landing site in the Taurus-Littrow valley. Free-air and Bouguer corrections were applied to the gravity data. The resultant Bouguer anomaly, analyzed with a two-dimensional approximation, shows a relative gravity maximum of about 25 to 30 mgal over the Taurus-Littrow valley. This maximum is interpreted in terms of a 1-km-thick block of basalt flow with a positive density contrast of 0.8 g/cu cm relative to the highland material on either side.

Preliminary Design of Nano Satellite for Regional Navigation System

NASA Astrophysics Data System (ADS)

Fathurrohim, L.; Poetro, R. E.; Kurniadi, B.; Fadillah, P. A.; Iqbal, M.

2018-04-01

A Low cost Regional Navigation Satellite System employing constellation of nano satellites has been proposed for Indonesian coverage. The constellation of Low Earth Orbit nano satellites off course will not be able to give better position fixed to the GPS. However, the design of navigation system has much lower in cost compare to the current navigation system. This paper tells about preliminary design of the proposed regional navigation satellite system. The results of our satellite design has 3 kg on its weight, 10 W on power requirement at the peak condition, and 2.7 years of lifetime. Payload communication of the satellite will use UHF and TT&C communication will use VHF. Total area of solar panel will be 0.11 m2.

Preliminary Design, Feasibility and Cost Evaluation of 1- to 15-Kilometer Height Steel Towers

NASA Technical Reports Server (NTRS)

Shanker, Ajay

2003-01-01

Design and construction of tall towers is an on-going research program of NASA. The agency has already done preliminary review in this area and has determined that multi-kilometer height towers are technically and economically feasible. The proposed towers will provide high altitude launch platforms reaching above eighty percent of Earth's atmosphere and provide tremendous gains in the potential energy as well as substantial reduction in aerodynamic drag. NASA has also determined that a 15-KM tower will have many useful applications in: (i)Meteorology,(ii)Oceanography, (iii)Astronomy, (iv)High Altitude Launch, (v)Physics Drop Tower, (vi) Biosphere Research, (vii) Nanotechnology, (viii) Energy/Power, (ix)Broadband Wireless Technology, (x)Space Transportation and (xi)Space Tourism.

LWS design replacement study: Optimum design and tradeoff analysis

NASA Technical Reports Server (NTRS)

1973-01-01

A design for two long-wavelength (LW) focal-plane and cooler assemblies, including associated preamplifiers and post-amplifiers is presented. The focal-planes and associated electronic assemblies are intended as direct replacement hardware to be installed into the existing 24-channel multispectral scanner used with the NASA Earth Observations Aircraft Program. An organization skilled in the art of LWIR systems can fabricate and deliver the two long-wavelength focal-plane assemblies described in this report when provided with the data and drawings developed during the performance of this contract. The concepts developed during the study including the alternative approaches and selection of components are discussed. Modifications to the preliminary design as reported in a preliminary design review meeting have also been included.

Space station assembly/servicing capabilities

NASA Technical Reports Server (NTRS)

Joyce, Joseph

1986-01-01

The aim is to place a permanently manned space station on-orbit around the Earth, which is international in scope. The program is nearing the close of the system definition and preliminary design phase. The first shuttle launch for space station assembly on-orbit is estimated for January 1993. Topics perceived to be important to on-orbit assembly and servicing are discussed. This presentation is represented by charts.

Not Even if You Were the Last Person on Earth! How Marital Search Constraints Affect the Likelihood of Marriage

ERIC Educational Resources Information Center

Raley, R. Kelly; Bratter, Jenifer

2004-01-01

Using the 1987-1988 and 1992-1994 waves of the National Survey of Families and Households, the authors measure the association between Wave 1 responses to 12 questions on whom respondents would be "most willing to marry" and the likelihood of marriage by Wave 2. Preliminary analysis indicated that some questions about partner preferences…

Preliminary observations of organic gas-particle partitioning from biomass combustion smoke using an aerosol mass spectrometer

Treesearch

T. Lee; S. M. Kreidenweis; J. L. Collett; A. P. Sullivan; C. M. Carrico; J. L. Jimenez; M. Cubison; S. Saarikoski; D. R. Worsnop; T. B. Onasch; E. Fortner; W. C. Malm; E. Lincoln; Cyle Wold; WeiMin Hao

2010-01-01

Aerosols play important roles in adverse health effects, indirect and direct forcing of Earth’s climate, and visibility degradation. Biomass burning emissions from wild and prescribed fires can make a significant contribution to ambient aerosol mass in many locations and seasons. In order to better understand the chemical properties of particles produced by combustion...