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Sample records for planetary interiors experiment

  1. Planetary Interiors

    NASA Technical Reports Server (NTRS)

    Banerdt, W. Bruce; Abercrombie, Rachel; Keddie, Susan; Mizutani, Hitoshi; Nagihara, Seiichi; Nakamura, Yosio; Pike, W. Thomas

    1996-01-01

    This report identifies two main themes to guide planetary science in the next two decades: understanding planetary origins, and understanding the constitution and fundamental processes of the planets themselves. Within the latter theme, four specific goals related to interior measurements addressing the theme. These are: (1) Understanding the internal structure and dynamics of at least one solid body, other than the Earth or Moon, that is actively convecting, (2) Determine the characteristics of the magnetic fields of Mercury and the outer planets to provide insight into the generation of planetary magnetic fields, (3) Specify the nature and sources of stress that are responsible for the global tectonics of Mars, Venus, and several icy satellites of the outer planets, and (4) Advance significantly our understanding of crust-mantle structure for all the solid planets. These goals can be addressed almost exclusively by measurements made on the surfaces of planetary bodies.

  2. Frontiers of the Physics of Dense Plasmas and Planetary Interiors: Experiment, Theory, Applications

    SciTech Connect

    Fortney, J J; Glenzer, S H; Koenig, M; Brambrink, E; Militzer, B; Saumon, D; Valencia, D

    2008-09-12

    We review recent developments of dynamic x-ray characterization experiments of dense matter, with particular emphasis on conditions relevant to interiors of terrestrial and gas giant planets. These studies include characterization of compressed states of matter in light elements by x-ray scattering and imaging of shocked iron by radiography. We examine several applications of this work. These include the structure of massive 'Super Earth' terrestrial planets around other stars, the 40 known extrasolar gas giants with measured masses and radii, and Jupiter itself, which serves as our benchmark for giant planets. We are now in an era of dramatic improvement in our knowledge of the physics of materials at high density. For light elements, this theoretical and experimental work has many applications, including internal confinement fusion as well as the interiors of gas giant planets. For heavy elements, experiments on silicates and iron at high pressure are helping to better understand the Earth, as well as terrestrial planets as a class of objects. In particular, the discovery of rocky and gaseous planets in other planetary systems has opened our imaginations to planets not found in our own solar system. While the fields of experiments of matter at high densities, first principles calculations of equations of state (EOS), planetary science, and astronomy do progress independently of each other, it is important for there to be communication between fields. For instance, in the realm of planets, physicists can learn of key problems that exist in the area of planetary structure, and how advances in our understanding of input physics could shed new light in this area. Astronomers and planetary scientists can learn where breakthroughs in physics of materials under extreme conditions are occurring, and be ready to apply these findings within their fields.

  3. Planetary seismology and interiors

    NASA Technical Reports Server (NTRS)

    Toksoz, M. N.

    1979-01-01

    This report briefly summarizes knowledge gained in the area of planetary seismology in the period 1969-1979. Attention is given to the seismic instruments, the seismic environment (noise, characteristics of seismic wave propagation, etc.), and the seismicity of the moon and Mars as determined by the Apollo missions and Viking Lander experiments, respectively. The models of internal structures of the terrestrial planets are discussed, with the earth used for reference.

  4. Planetary Interiors and Geodesy

    NASA Astrophysics Data System (ADS)

    Dehant, Veronique

    2013-04-01

    Lander and orbiter, even rover at the surface of planets or moons of the solar system help in determining their interior properties. First of all orbiters feel the gravity of the planet and its change. In particular, the tidal mass redistribution induces changes in the acceleration of the spacecraft orbiting around a planet. The Love number k2 has been determined for Venus, Mars and the Earth, as well as for Titan and will be deduced for instance for Mercury (MESSENGER and BepiColombo missions) and for the Galilean satellite from new missions such as JUICE (Jupiter Icy satellite Explorer). The properties of the interior can also be determined from the observation of the rotation of the celestial body. Radar observation from the Earth ground stations of Mercury has allowed Margo et al. (2012, JGR) to determine the moments of inertia of Mercury with an unprecedented accuracy. Rovers such as the MERs (Mars Exploration Rovers) allow as well to obtain the precession and nutation of Mars from which the moments of inertia of the planet and its core can be deduced. Future missions such as InSIGHT (Interior exploration using Seismic Investigations, Geodesy, and Heat Transport) will further help in the determination of Mars interior and evolution.

  5. Planetary Interior in the Laboratory

    SciTech Connect

    Chau, R; Bastea, M; Mitchell, A C; Minich, R W; Nellis, W J

    2003-01-31

    In the three years of this project, we have provided a complete database of the electrical conductivity of planetary materials to 180 GPa. The electrical conductivities of these planetary materials now provide a basis for future modeling of planets taking into account full magnetohydrodynamics. By using a full magnetohydrodynamics simulation, the magnetic fields of the planets can then be taken into account. Moreover, the electrical conductivities of the planetary materials have given us insight into the structure and nature of these dense fluids. We showed that simple monoatomic fluids such as hydrogen, nitrogen, and oxygen at planetary interior conditions undergo a common metallization process which can be explained on a simple basis of their radial charge density distributions. This model also shows that the metallization process is actually rather common and likely to take place in a number of materials such as carbon monoxide which is also present within planetary objects. On the other hand, we have also showed that a simple two component fluid like water and methane take on much different behaviors than say nitrogen due to the chemical interactions within these systems. The dynamics of an even more complex system, ''synthetic Uranus'' are still being analyzed but suggest that on some levels the behavior is very simple, i.e. the electrical conductivity is essentially the same as water, but the local dynamics are very complex. This project has shed much light on the nature of electrical transport within planetary interiors but also has shown that understanding chemical processes in the complex fluids within planetary interiors to be very important. Understanding those local interactions and processes is required to gain further insight into planetary interiors.

  6. Sinking Deep in to a Carbon-Rich Planet: Using Experiments to Constrain Planetary Interiors

    NASA Astrophysics Data System (ADS)

    Lee, K. K. M.; Daviau, K.

    2015-05-01

    Recent detection of C-rich exoplanet atmospheres and the possibility of C-rich interiors, lends itself to the discussion of what a C-rich interior might look like and how it behaves. We use new experiments on SiC at high P/T for new constraints.

  7. Frontier of the physics of dense plasmas and planetary interiors: experiments, theory, applications

    SciTech Connect

    Saumon, Didier; Fortney, Jonathan J; Glenzer, Siegfried H; Koenig, Michel; Brambrink, E; Militzer, Burkhard; Valencia, Diana

    2008-01-01

    Recent developments of dynamic x-ray characterization experiments of dense matter are reviewed, with particular emphasis on conditions relevant to interiors of terrestrial and gas giant planets. These studies include characterization of compressed states of matter in light elements by x-ray scattering and imaging of shocked iron by radiography. Several applications of this work are examined. These include the structure of massive 'super-Earth' terrestrial planets around other stars, the 40 known extrasolar gas giants with measured masses and radii, and Jupiter itself, which serves as the benchmark for giant planets.

  8. Interactive investigations into planetary interiors

    NASA Astrophysics Data System (ADS)

    Rose, I.

    2015-12-01

    Many processes in Earth science are difficult to observe or visualize due to the large timescales and lengthscales over which they operate. The dynamics of planetary mantles are particularly challenging as we cannot even look at the rocks involved. As a result, much teaching material on mantle dynamics relies on static images and cartoons, many of which are decades old. Recent improvements in computing power and technology (largely driven by game and web development) have allowed for advances in real-time physics simulations and visualizations, but these have been slow to affect Earth science education.Here I demonstrate a teaching tool for mantle convection and seismology which solves the equations for conservation of mass, momentum, and energy in real time, allowing users make changes to the simulation and immediately see the effects. The user can ask and answer questions about what happens when they add heat in one place, or take it away from another place, or increase the temperature at the base of the mantle. They can also pause the simulation, and while it is paused, create and visualize seismic waves traveling through the mantle. These allow for investigations into and discussions about plate tectonics, earthquakes, hot spot volcanism, and planetary cooling.The simulation is rendered to the screen using OpenGL, and is cross-platform. It can be run as a native application for maximum performance, but it can also be embedded in a web browser for easy deployment and portability.

  9. Planetary deep interiors, geodesy, and habitability

    NASA Astrophysics Data System (ADS)

    Dehant, Veronique

    2014-05-01

    The evolution of planets is driven by the composition, structure, and thermal state of their internal core, mantle, lithosphere, crust, and by interactions with possible ocean and atmosphere. This presentation puts in perspective the fundamental understanding of the relationships and interactions between those different planetary reservoirs and their evolution through time. It emphasizes on the deep interior part of terrestrial planets and moons. The core of a planet, when composed of liquid iron alloy, may provide magnetic field and further interaction with the magnetosphere, ingredients believed to be important for the evolution of an atmosphere and of a planet in general. The deep interior is believed to be of high importance for its habitability. Lander and orbiter, even rover at the surface of planets or moons of the solar system help in determining their interior properties. First of all orbiters feel the gravity of the planet and its variations. In particular, the tidal mass redistribution induces changes in the acceleration of the spacecraft orbiting around a planet. The Love number k2 has been determined for Venus, Mars, and the Earth, as well as for Titan and will be deduced for Mercury and for some of the Galilean satellites from new missions such as JUICE (Jupiter Icy satellite Explorer). The properties of the interior can also be determined from the observation of the rotation of the celestial body. Radar observation from the Earth ground stations of Mercury has allowed Margo et al. (2012, JGR) to determine the moments of inertia of Mercury with an unprecedented accuracy. Rovers such as the MERs (Mars Exploration Rovers) allow as well to obtain the precession and nutation of Mars from which the moments of inertia of the planet and its core can be deduced. Future missions such as the InSIGHT (Interior exploration using Seismic Investigations, Geodesy, and Heat Transport) NASA mission will further help in the determination of Mars interior and evolution

  10. Simulation of the Planetary Interior Differentiation Processes in the Laboratory

    PubMed Central

    Fei, Yingwei

    2013-01-01

    A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to that layered structure, (1) percolation of liquid metal in a solid silicate matrix by planet differentiation, and (2) inner core crystallization by subsequent planet cooling. We conduct high-pressure and high-temperature experiments to simulate both processes in the laboratory. Formation of percolative planetary core depends on the efficiency of melt percolation, which is controlled by the dihedral (wetting) angle. The percolation simulation includes heating the sample at high pressure to a target temperature at which iron-sulfur alloy is molten while the silicate remains solid, and then determining the true dihedral angle to evaluate the style of liquid migration in a crystalline matrix by 3D visualization. The 3D volume rendering is achieved by slicing the recovered sample with a focused ion beam (FIB) and taking SEM image of each slice with a FIB/SEM crossbeam instrument. The second set of experiments is designed to understand the inner core crystallization and element distribution between the liquid outer core and solid inner core by determining the melting temperature and element partitioning at high pressure. The melting experiments are conducted in the multi-anvil apparatus up to 27 GPa and extended to higher pressure in the diamond-anvil cell with laser-heating. We have developed techniques to recover small heated samples by precision FIB milling and obtain high-resolution images of the laser-heated spot that show melting texture at high pressure. By analyzing the chemical compositions of the coexisting liquid and solid phases, we precisely determine the liquidus curve, providing necessary data to understand the inner core crystallization process. PMID:24326245

  11. Simulation of the planetary interior differentiation processes in the laboratory.

    PubMed

    Fei, Yingwei

    2013-01-01

    A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to that layered structure, (1) percolation of liquid metal in a solid silicate matrix by planet differentiation, and (2) inner core crystallization by subsequent planet cooling. We conduct high-pressure and high-temperature experiments to simulate both processes in the laboratory. Formation of percolative planetary core depends on the efficiency of melt percolation, which is controlled by the dihedral (wetting) angle. The percolation simulation includes heating the sample at high pressure to a target temperature at which iron-sulfur alloy is molten while the silicate remains solid, and then determining the true dihedral angle to evaluate the style of liquid migration in a crystalline matrix by 3D visualization. The 3D volume rendering is achieved by slicing the recovered sample with a focused ion beam (FIB) and taking SEM image of each slice with a FIB/SEM crossbeam instrument. The second set of experiments is designed to understand the inner core crystallization and element distribution between the liquid outer core and solid inner core by determining the melting temperature and element partitioning at high pressure. The melting experiments are conducted in the multi-anvil apparatus up to 27 GPa and extended to higher pressure in the diamond-anvil cell with laser-heating. We have developed techniques to recover small heated samples by precision FIB milling and obtain high-resolution images of the laser-heated spot that show melting texture at high pressure. By analyzing the chemical compositions of the coexisting liquid and solid phases, we precisely determine the liquidus curve, providing necessary data to understand the inner core crystallization process. PMID:24326245

  12. Geometrodynamical Fluid Theory Applied to Dynamo Flows in Planetary Interiors

    NASA Astrophysics Data System (ADS)

    Lewis, Kayla; Miramontes, Diego; Scofield, Dillon

    2015-11-01

    Due to their reliance on a Newtonian viscous stress model, the traditional Navier-Stokes equations are of parabolic type; this in turn leads to acausal behavior of solutions to these equations, e.g., a localized disturbance at any point instantaneously affects the solution arbitrarily far away. Geometrodynamical fluid theory (GFT) avoids this problem through a relativistically covariant formulation of the flow equations. Using GFT, we derive the magnetohydrodynamic equations describing the balance of energy-momentum appropriate for dynamo flows in planetary interiors. These equations include interactions between magnetic and fluid vortex fields. We derive scaling laws from these equations and compare them with scaling laws derived from the traditional approach. Finally, we discuss implications of these scalings for flows in planetary dynamos.

  13. Planetary entry experiments

    NASA Technical Reports Server (NTRS)

    Craig, Roger A.

    1994-01-01

    The final report summarizes the results from three research areas: (1) window design for the radiometric measurement of the forebody radiative heating experienced by atmospheric entry spaceraft; (2) survey of the current understanding of chemical species on selected solar system bodies and assess the importance of measurements with regard to vehicle environment and with regard to understanding of planetary atmospheres with emphasis on Venus, Mars, and Titan; and (3) measure and analyze the radiation (VUV to near-IR) from the shock heated gas cap of a blunt body in an Ames arc Jet wind-tunnel facility.

  14. Numerical study of librationally driven Flow in planetary interiors

    NASA Astrophysics Data System (ADS)

    Laguerre, Raphael; Karatekin, Ozgur; Noir, Jérôme

    2010-05-01

    Forced librations are observed for many planetary bodies. In the case of interior fluid layers, i.e. liquid cores or subsurface oceans, the resulting librational response could be different compared to that of a solid body. The coupling between the fluid layer and mantle depends strongly on the interior properties of the planet. Here we study numerically the properties of a librationally driven flow by taking into account both longitudinal and latitudinal forcing. The numerical method is based on an finite element approximation in meridian planes and a Fourier decomposition of the variables in the azimuthal direction (SFEMANS, Spectral Finite Element for Maxwell and Navier Stokes ). This allows us to specify the direction of rotation vector arbitrarily. In the case of longitudinal forcing we compare our solutions to the experimental results of Noir et al. 2009 obtained for cores with spherical shape. For latitudinal librations, we consider also the influence of ellipticity.

  15. Phase relation of C-Mg-Fe-Si-O system under various oxygen fugacity conditions by in situ X-ray diffraction experiments: Implication for planetary interior

    NASA Astrophysics Data System (ADS)

    Takahashi, S.; Ohtani, E.; Terasaki, H.; Ito, Y.; Funakoshi, K.; Higo, Y.

    2011-12-01

    Carbon is one of the major volatile elements and very important in the Earth, primitive meteorites and some achondrites, such as ureilites. The abundance of carbon has been estimated to be 100 times higher than that in the CI chondrite, in some of the stars with exoplanets, such as the circumstellar gas around Beta Pictoris (Roberge et al., 2006). In such a gas, carbon-enriched planets, "carbon-planet", may be formed. Carbon-planet interior is likely to be composed mainly of Carbon-bearing phase, such as carbide, carbonate, graphite and diamond. Therefore, it is important to investigate phase relations of carbon-rich systems under high pressure conditions. In this study, C-enriched Mg-Si-Fe-O system was investigated at high pressure and temperature in order to understand the internal structure of the carbon-planets. Phase relations were studied based on 2 series of experiments; (I) textural observation and chemical analysis of the sample recovered from high pressure and temperature and (II) in situ X-ray diffraction experiments. We used several different mineral assemblages for the starting materials, as shown below: (i) (Mg1.8,Fe0.2)SiO4 + Fe + SiO2 + C, (ii) (Mg1.8,Fe0.2)SiO4 + Fe + Si + C, (iii) MgO + Fe + SiO2 + C, (iv) MgO + Fe + Si + C. Oxygen fugacity (fO2) of the sample varies depending on these assembleges due to different O amounts in the starting materials. Chemical analyses of the recovered samples were performed using an electron microprobe. In situ X-ray diffraction experiments were conducted at 4 and 15 GPa, and up to 1873 K at BL04B1 beamline, SPring-8 synchrotron facility. Different mineral assemblages were observed depending on the redox condition of the sample. The compositions of metallic melts changes from Fe-C compositions in oxidizing conditions to Fe-Si compositions in the reducing conditions. Based on in situ X-ray diffraction experiments at 4 GPa, FeSi and SiC peaks appeared at 1373 K in the most reducing sample (iv), whereas Fe3C appeared

  16. Constraining planetary interiors with the Love number k2

    NASA Astrophysics Data System (ADS)

    Kramm, Ulrike; Nettelmann, Nadine; Redmer, Ronald

    2011-11-01

    For the solar sytem giant planets the measurement of the gravitational moments J2 and J4 provided valuable information about the interior structure. However, for extrasolar planets the gravitational moments are not accessible. Nevertheless, an additional constraint for extrasolar planets can be obtained from the tidal Love number k2, which, to first order, is equivalent to J2. k2 quantifies the quadrupolic gravity field deformation at the surface of the planet in response to an external perturbing body and depends solely on the planet's internal density distribution. On the other hand, the inverse deduction of the density distribution of the planet from k2 is non-unique. The Love number k2 is a potentially observable parameter that can be obtained from tidally induced apsidal precession of close-in planets (Ragozzine & Wolf 2009) or from the orbital parameters of specific two-planet systems in apsidal alignment (Mardling 2007). We find that for a given k2, a precise value for the core mass cannot be derived. However, a maximum core mass can be inferred which equals the core mass predicted by homogeneous zero metallicity envelope models. Using the example of the extrasolar transiting planet HAT-P-13b we show to what extend planetary models can be constrained by taking into account the tidal Love number k2.

  17. Hypervelocity impacts and the evolution of planetary surfaces and interiors

    NASA Astrophysics Data System (ADS)

    Watters, Wesley Andres

    2009-06-01

    The thesis consists of five studies relating impact processes to the evolution of planetary interiors as well as impact structures on planetary surfaces. Chapter 2 is concerned with developing methods for estimating the amount of heat deposited deep in terrestrial mantles by large impacts. Chapter 3 makes use of these results to compute the consequences of impact-related thermal buoyancy perturbations in numerical models of subsolidus convection. Among the important results of this work is a relation for the time-scale on which a buoyancy anomaly flattens and spreads before it is halted by convective downflows, as well as a condition that indicates for what perturbation magnitudes and Rayleigh numbers the flow is significantly slowed at a global scale. Chapter 4 describes a structural model of Endurance Crater in Meridiani Planum on Mars, which is constrained by observations gathered by the MER- B Opportunity rover. These results reveal new insights about the planform shape of the crater excavation flow, as well as the connection between crater shape and pre-existing structures in target materials. The study presented in chapter 5 relates the planimetric shape of simple impact craters on Mars ( D < 5 km) to the geological targets in which they form, as well as rim diameter. Planform crater shape is characterized by a suite of morphometric parameters, including Fourier harmonic amplitudes and phase angles, as well as measures of deviation from radial symmetry and convexity. In addition to finding the morphometric dependence on target properties, this work has illuminated prominent transitions between different cratering regimes, and contains a measure of the global distribution of planform elongation azimuths -- which may relate to impact azimuth and provide an estimate of Mars' past obliquity variations. Finally, Chapter 6 describes a stochastic-kinematic model of the interaction between the excavation front and fractures in the target, which replicates many of the

  18. Isentropic compression of hydrogen: Probing conditions deep in planetary interiors

    NASA Astrophysics Data System (ADS)

    Becker, Andreas; Nettelmann, Nadine; Holst, Bastian; Redmer, Ronald

    2013-07-01

    We perform ab initio calculations for the equation of state of dense liquid hydrogen and deuterium using quantum molecular dynamics simulations based on finite-temperature density functional theory. This extensive data set allows us to determine specific density-temperature-pressure tracks such as the cold curve, precompressed and principal Hugoniot curves, and isentropes which are essential for the analysis and interpretation of high-pressure experiments. In this study we focus on conditions probed by recent quasi-isentropic shock compression experiments that have reached a so-far unprecedented 108-fold compression of gaseous deuterium. As these states of matter are relevant for the deep interior of Jupiter-like exoplanets we simultaneously give predictions for their isentropes.

  19. Planetary Dynamos: Magnetic Constraints on the Interior Structure and Evolution of a Planet

    NASA Astrophysics Data System (ADS)

    Tian, Bob Yunsheng

    Planetary magnetism is a phenomenon that not only protects humanity from the destructive forces of nature, but also provides us with a natural probe into our planet's deep interior. In this dissertation, I will explore some of the insights concerning planetary interiors that can be gained by combining the techniques of interior structure modelling with constraints provided by planetary dynamo theory. Applications to the dynamical history of the Moon, the interior evolution of Jovian planets, and predicted magnetic fields of planets in our solar system and beyond are considered under this framework. The inferred intensity and longevity of the lunar dynamo from paleomagnetic studies has led to the proposition of mechanical stirring, caused by differential rotation of the inner core and the mantle relative to the fluid outer core, as an energy source alternative to convection. Using fully three-dimensional magnetohydrodynamics (MHD) modelling techniques, I simulated the purported mechanism, and found it to reproduce not only the strength and longevity of the inferred lunar dynamo, but also its precipitous decline later in its history. For the Jovian planets, due to the lack of constraints, there are a wide range of acceptable interior models in the literature. By combining 1-D interior modelling techniques with constraints imposed by theories of the planet's dynamo, I was able to construct improved models of these planets' interior structure. The discrepancy between the pictures of the Neptunian interior suggested by dynamo models and by thermal evolution models motivated improvements on our current theories about multipolar magnetic field generation. Therefore, I determined some predictive scaling laws for the magnetic field morphologies of planets (and exoplanets) using parameter studies of interior structure and dynamo models. These results will aid in our understandings of the link between interior properties and observed magnetic field characteristics for planets

  20. Carbon precipitation from heavy hydrocarbon fluid in deep planetary interiors.

    PubMed

    Lobanov, Sergey S; Chen, Pei-Nan; Chen, Xiao-Jia; Zha, Chang-Sheng; Litasov, Konstantin D; Mao, Ho-Kwang; Goncharov, Alexander F

    2013-01-01

    The phase diagram of the carbon-hydrogen system is of great importance to planetary sciences, as hydrocarbons comprise a significant part of icy giant planets and are involved in reduced carbon-oxygen-hydrogen fluid in the deep Earth. Here we use resistively- and laser-heated diamond anvil cells to measure methane melting and chemical reactivity up to 80 GPa and 2,000 K. We show that methane melts congruently below 40 GPa. Hydrogen and elementary carbon appear at temperatures of >1,200 K, whereas heavier alkanes and unsaturated hydrocarbons (>24 GPa) form in melts of >1,500 K. The phase composition of carbon-hydrogen fluid evolves towards heavy hydrocarbons at pressures and temperatures representative of Earth's lower mantle. We argue that reduced mantle fluids precipitate diamond upon re-equilibration to lighter species in the upwelling mantle. Likewise, our findings suggest that geophysical models of Uranus and Neptune require reassessment because chemical reactivity of planetary ices is underestimated. PMID:24026399

  1. Study of the Warm Dense Matter with XANES spectroscopy - Applications to planetary interiors

    NASA Astrophysics Data System (ADS)

    Denoeud, Adrien

    With the recent discovery of many exoplanets, modelling the interior of these celestial bodies is becoming a fascinating scientific challenge. In this context, it is crucial to accurately know the equations of state and the macroscopic and microscopic physical properties of their constituent materials in the Warm Dense Matter regime (WDM). Moreover, planetary models rely almost exclusively on physical properties obtained using first principles simulations based on density functional theory (DFT) predictions. It is thus of paramount importance to validate the basic underlying mechanisms occurring for key planetary constituents (metallization, dissociation, structural modifications, phase transitions, etc....) as pressure and temperature both increase. In this work, we were interested in two materials that can be mainly found in the Earth-like planets: silica, or SiO2, as a model compound of the silicates that constitute the major part of their mantles, and iron, which is found in abundance in their cores. These two materials were compressed and brought to the WDM regime by using strong shock created by laser pulses during various experiments performed on the LULI2000 (Palaiseau, France) and the JLF (Livermore, US) laser facilities and on the LCLS XFEL (Stanford, US). In order to penetrate this dense matter and to have access to its both ionic and electronic structures, we have probed silica and iron with time-resolved X-ray Absorption Near Edge Structure (XANES). In parallel with these experiments, we performed quantum molecular dynamics simulations based on DFT at conditions representative of the region investigated experimentally so as to extract the interesting physical processes and comprehend the limits of the implemented models. In particular, these works allowed us to highlight the metallization processes of silica in temperature and the structural changes of its liquid in density, as well as to more constrain the melting curve of iron at very high pressures.

  2. Experimental study of planetary gases with applications to planetary interior models

    NASA Technical Reports Server (NTRS)

    Bell, Peter M.; Mao, Ho-Kwang

    1988-01-01

    High-pressure experimental data on planetary materials are critical in developing planetary models and in addressing otherwise insoluble problems of the internal structure of the major planets. Progress in the last five years has been particularly marked. Maximum static pressure of 550 GPa was achieved. For the first time, X-ray diffraction of solidified gases (Ne, Xe) and ices (H2O) were obtained at pressures above one megabar, single-crystal diffraction of ultralight elements (H2, He) were detected up to 25 GPa, pressures over 200 GPa at 77 K were reached in solid hydrogen, including the discovery of a phase transformation in the molecular solid. Advances in instrumentation and new measurements performed during 1983 to 1988 are summarized.

  3. Recreating planetary interiors in the laboratory by laser-driven ramp-compression

    NASA Astrophysics Data System (ADS)

    Coppari, Federica

    2015-06-01

    Recent advances in laser-driven compression now allow to reproduce conditions existing deep inside large planets in the laboratory. Ramp-compression allows to compress matter along a thermodynamic path not accessible through standard shock compression techniques, and opens the way to the exploration of new pressure, density and temperature conditions. By carefully tuning the laser pulse shape we can compress the material to extremely high pressure and keep the temperature relatively low (i.e. below the melting temperature). In this way, we can probe solid states of matter at unprecedented high pressures. This loading technique has been combined with diagnostics generally used in condensed matter physics, such as x-ray diffraction and x-ray absorption spectroscopy (EXAFS, Extended X-ray Absorption Fine Structure, in particular), to provide a complete picture of the behavior of matter in-situ during compression. X-ray diffraction provides a snapshot of the structure and density of the material, while EXAFS has been used to infer the temperature. Simultaneous optical velocimetry measurements using VISAR (Velocity Interferometer for Any Reflector) yield an accurate determination of the pressure history during compression. In this talk I will present some of the results obtained in ramp-compression experiments performed at the Omega Laser Facility (University of Rochester) where the phase maps of planetary relevant materials, such as Fe, FeO and MgO, have been studied to unprecedented high pressures. Our data provide experimental constraints on the equations of state, strength and structure of these materials expected to dominate the interiors of massive rocky extra-solar planets and a benchmark for theoretical simulations. Combination of these new experimental data with models for planetary formation and evolutions is expected to improve our understanding of complex dynamics occurring in the Universe. This work was performed under the auspices of the US Department of

  4. Compressibility and planetary interiors. [solid core theory applicable to Earth and Venus

    NASA Technical Reports Server (NTRS)

    Bullen, K. E.

    1972-01-01

    Important confirmations that the Earth's inner core is solid have recently come from analyses of records of free Earth oscillations and from the apparent detection of the seismic phase PKJKP. Corresponding support is given to the theory which supplied the primary evidence for rigidity in the inner core. This theory requires the incompressibility and its gradient with respect to the pressure p to vary fairly smoothly with p inside planets, and supplies a potent restriction on the allowable variations of particular physical properties inside parts of planetary interiors. The theory is at present principally applicable to the Earth and Venus. The paper reviews some of the principal implications.

  5. Planetary/DOD entry technology flight experiments. Volume 2: Planetary entry flight experiments

    NASA Technical Reports Server (NTRS)

    Christensen, H. E.; Krieger, R. J.; Mcneilly, W. R.; Vetter, H. C.

    1976-01-01

    The technical feasibility of launching a high speed, earth entry vehicle from the space shuttle to advance technology for the exploration of the outer planets' atmospheres was established. Disciplines of thermodynamics, orbital mechanics, aerodynamics propulsion, structures, design, electronics and system integration focused on the goal of producing outer planet environments on a probe shaped vehicle during an earth entry. Major aspects of analysis and vehicle design studied include: planetary environments, earth entry environment capability, mission maneuvers, capabilities of shuttle upper stages, a comparison of earth entry planetary environments, experiment design and vehicle design.

  6. The interior configuration of planet Mercury constrained by moment of inertia and planetary contraction

    NASA Astrophysics Data System (ADS)

    Knibbe, J. S.; Westrenen, W.

    2015-11-01

    This paper presents an analysis of present-day interior configuration models for Mercury considering cores of Fe-S or Fe-Si alloy, the latter possibly covered by a solid FeS layer, in light of the improved limit of planetary contraction of 7 km derived from MErcury Surface, Space ENvironment, GEochemistry, and Ranging observations of surface landforms. Density profiles, generated by a Monte Carlo approach, are constrained by Mercury's mass, polar moment of inertia (C), fraction of polar moment corresponding to its outer solid shell (Cm/C), and observed planetary contraction. Results show that the outer liquid core boundary is constrained to 1985-2090 km in radius, where large radii correspond to high Si and S core contents and high mantle densities or the presence of an FeS layer at the top of the outer core. The bulk core S and Si contents are within 2.8-8.9 wt % and above 8.5 wt %, respectively, where an increase of light element core content correlates positively with mantle density and core size. The size of the inner core is constrained by the observed planetary contraction to below 1454 or 1543 km in radius for bulk cores rich in S (near 8.9 wt %) or Si (near 25 wt %), respectively. For cores poor in light elements, inner cores up to 1690 km in radius remain consistent with the observed planetary contraction. Finally, we show that solid FeS at outer core conditions, previously argued to float on liquid Fe-S, may be denser than the residual liquid. This implies that a separate mechanism may be required to maintain an FeS layer at the suggested location.

  7. The Mars Plant Growth Experiment and Implications for Planetary Protection

    NASA Astrophysics Data System (ADS)

    Smith, Heather

    Plants are the ultimate and necessary solution for O2 production at a human base on Mars. Currently it is unknown if seeds can germinate on the Martian surface. The Mars Plant growth experiment (MPX) is a proposal for the first step in the development of a plant- based O2 production system by demonstrating plant germination and growth on the Martian surface. There is currently no planetary protection policy in place that covers plants on the Martian surface. We describe a planetary protection plan in compliance with NASA and COSPAR policy for a closed plant growth chamber on a Mars rover. We divide the plant growth chamber into two categories for planetary protection, the Outside: the outside of the chamber exposed to the Martian environment, and the Inside: the inside of the chamber which is sealed off from Mars atmosphere and contains the plant seeds and ancillary components for seed growth. We will treat outside surfaces of the chamber as other outside surfaces on the rover, wiped with a mixture of isopropyl alcohol and water as per Category IVb planetary protection requirements. All internal components of the MPX except the seeds and camera (including the water system, the plant growth stage and interior surface walls) will be sterilized by autoclave and subjected to sterilizing dry heat at a temperature of 125°C at an absolute humidity corresponding to a relative humidity of less than 25 percent referenced to the standard conditions of 0°C and 760 torr pressure. The seeds and internal compartments of the MPX in contact with the growth media will be assembled and tested to be free of viable microbes. MPX, once assembled, cannot survive Dry Heat Microbial Reduction. The camera with the radiation and CO2 sensors will be sealed in their own container and vented through HEPA filters. The seeds will be vernalized (microbe free) as per current Space Station methods described by Paul et al. 2001. Documentation of the lack of viable microbes on representative seeds

  8. Impact-induced shock pressure distribution in a heterogeneous planetary interior

    NASA Astrophysics Data System (ADS)

    Arkani-Hamed, J.

    2012-12-01

    The shock pressure distribution inside planetary interiors has been investigated on the basis of scaling laws [1,2] and using numerical hydrocode models [2,3]. Here I present a new shock ray formulations derived on the basis of the Hugoniot equations to calculate the impact-induced shock pressure distribution inside heterogeneous terrestrial planets with radially varying physical parameters both in the solid mantle and in the underlying liquid core. Considering a single vertical impact, the formulations are derived in an axi-symmetric spherical coordinate system where the impact is assumed to occur at the north pole. In previous studies the scaling laws of shock pressure distribution [5] have been used to determine the impact heating of the planetary interiors by direct shock waves [2]. Because the main concern was the impact heating of the core, the heating of the antipodal region of the mantle was not investigated. The present study not only considers the impact heating of the entire planetary mantle by direct shock waves but also investigates the effects of the reflected shock waves inside the core. The direct shockwave propagating southward in the core intersects the core mantle boundary in the antipodal region where it partly transmits to the mantle and partly reflects back into the core. Both transmitted and reflected waves converge toward the axis of symmetry and create strong shock pressure near the axis in the antipodal region. Consequently, the antipodal region is significantly heated. In particular, the antipodal region of the core is heated twice, first by the direct shock wave as it propagates southward, and second by the reflected waves which actually increases in intensity close to the axis of symmetry. This feature has been demonstrated by the hydrocode models [3,4] but not by the scaling models based on direct shock wave propagation [1]. The new algorithm is applied to the impact heating of Mars, and the results are compared with those determined

  9. A tracers method for studying double diffusive convection in the liquid layers of planetary interiors

    NASA Astrophysics Data System (ADS)

    Bouffard, M.; Labrosse, M.; Choblet, M.; Fournier, M.; Aubert, M.; Tackley, M.

    2015-10-01

    Convection in the liquid layers of planetary interiors is usually driven by a combination of thermal and compositional sources of buoyancy. The low molecular diffusivity of composition causes troubles in the description of this field on the Eulerian grids typically employed in current codes of geodynamo because numerical diffusion on these grids is potentially larger than the real diffusivity. We developed a Lagrangian description of composition based on a method of tracers. The absence of numerical diffusion inherent to this method allows modeling of thermo-chemical convection with infinite Lewis number. The validation of this new tool on benchmark cases will be presented at EPSC as well as its first applications to the ocean of Ganymede with consistently coupled boundary condi- tions for temperature and composition.

  10. Nature of the interior of Uranus based on studies of planetary ices at high dynamic pressure

    SciTech Connect

    Nellis, W.J.; Hamilton, D.C.; Holmes, N.C.; Radousky, H.B.; Ree, F.H.; Mitchell, A.C.; Nicol, M.

    1988-05-06

    Data from the Voyager II spacecraft showed that Uranus has a large magnetic field with geometry similar to an offset tilted dipole. To interpret the origin of the magnetic field, measurements were made of electrical conductivity and equation-of-state data of the planetary ices ammonia, methane, and synthetic Uranus at shock pressures and temperatures up to 75 gigapascals and 5000 K. These pressures and temperatures correspond to conditions at the depths at which the surface magnetic field is generated. Above 40 gigapascals the conductivities of synthetic Uranus, water, and ammonia plateau at about 20 (ohm-cm)/sup -1/, providing an upper limit for the electrical conductivity used in kinematic or dynamo calculations. The nature of materials at the extreme conditions in the interior is discussed. 29 references, 3 figures.

  11. Shockwave determination of the shear velocity at very high pressures. [for determining properties of planetary interiors

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.

    1972-01-01

    A shock wave experiment is described for confirming changes in density, from seismic interpretation, for determining the properties of planet interiors. The experiment focuses on the problem of measurements in a pressure region, where the shear velocity tends to vanish, or become very small. Pressure-sensitive lattice stability, and the equations for an atomic model of the NaCl lattice are discussed along with the particle velocity shock technique.

  12. Probing planetary interiors: Shock compression of water to 700 GPa and 3.8 g/cc, and recent high precision Hugoniot measurements of deuterium

    NASA Astrophysics Data System (ADS)

    Knudson, Marcus

    2013-06-01

    The past several years have seen tremendous increase in the number of identified extra-solar planetary systems. Our understanding of the formation of these systems is tied to our understanding of the internal structure of these exoplanets, which in turn rely upon equations of state of light elements and compounds such as water and hydrogen. Here we present shock compression data for water with unprecedented accuracy that shows commonly used models for water in planetary modeling significantly overestimate the compressibility at conditions relevant to planetary interiors. Furthermore, we show that its behavior at these conditions, including reflectivity and isentropic response, is well described by a recent first-principles based equation of state. These findings advocate the use of this model as the standard for modeling Neptune, Uranus, and ``hot Neptune'' exoplanets, and should contribute to improved understanding of the interior structure of these planets, and perhaps improved understanding of formation mechanisms of planetary systems. We also present very recent experiments on deuterium that have taken advantage of continued improvements in both experimental configuration and the understanding of the quartz shock standard to obtain Hugoniot data with a significant increase in precision. These data will prove to provide a stringent test for the equation of state of hydrogen and its isotopes. Sandia is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the US Department of Energy's National Nuclear Security Administration under Contract No. DE-ACO4-94AL85000.

  13. Experiments on planetary ices at UCL

    NASA Astrophysics Data System (ADS)

    Grindrod, P. M.; Fortes, A. D.; Wood, I. G.; Dobson, D.; Sammonds, P. R.; Stone-Drake, L.; Vocadlo, L.

    2007-08-01

    Using a suite of techniques and equipment, we conduct several different types of experiments on planetary ices at UCL. Samples are prepared in the Ice Physics Laboratory, which consists of a 5 chamber complex of inter-connected cold rooms, controllable from +30 to -30 deg C. Within this laboratory we have a functioning triaxial deformation cell operating at low temperature (down to -90 deg C) and high pressures (300 MPa), an Automatic Ice Fabric Analyser (AIFA) and a low-temperature microscope with CCD output. Polycrystalline samples, 40mm diameter by 100mm long, are compressed in the triaxial rig with a confining pressure; single crystal specimens are compressed in a separate uniaxial creep rig which operates at zero confining pressure for surface studies. A cold stage is also available for study of ice microstructural studies on our new Jeol JSM-6480LV SEM, which also allows tensile, compression and/or bending tests, with load ranges from less than 2N to 5000N. Finally, we also use a cold stage on a new PANalytical, X'pert PRO MPD, high resolution powder diffractometer to study the structure and phase behaviour of icy materials. Recent highlights of our work include: (1) derivation of a manufacturing process for methane clathrate at low temperatures, analysed in the X-Ray Diffraction Laboratory, for future rheological experiments, (2) analysed the growth behaviour of MS11, (3) refurbished and commenced calibration tests on the triaxial deformation cell using ice Ih, and (4) performed creep tests on gypsum and epsomite using the single crystal deformation cell. Further experiments will build on these preliminary results.

  14. The NASA planetary biology internship experience

    NASA Technical Reports Server (NTRS)

    Hinkle, G.; Margulis, L.

    1991-01-01

    By providing students from around the world with the opportunity to work with established scientists in the fields of biogeochemistry, remote sensing, and origins of life, among others, the NASA Planetary Biology Internship (PBI) Program has successfully launched many scientific careers. Each year approximately ten interns participate in research related to planetary biology at NASA Centers, NASA-sponsored research in university laboratories, and private institutions. The PBI program also sponsors three students every year in both the Microbiology and Marine Ecology summer courses at the Marine Biological Laboratory. Other information about the PBI Program is presented including application procedure.

  15. Interior. Plantcrushing and fiberprocessing apparatus used in latexextraction experiments. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior. Plant-crushing and fiber-processing apparatus used in latex-extraction experiments. - Thomas A. Edison Laboratories, Building No. 2, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

  16. Interior. Plantcrushing and fiberprocessing equipment used in latexextraction experiments. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior. Plant-crushing and fiber-processing equipment used in latex-extraction experiments. - Thomas A. Edison Laboratories, Building No. 2, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

  17. Core petrology: Implications for the dynamics and evolution of planetary interiors

    NASA Astrophysics Data System (ADS)

    Hauck, S. A.; Van Orman, J. A.

    2011-12-01

    The Earth, Mercury and Ganymede represent an exclusive group of terrestrial planetary bodies with present-day magnetic fields generated within their metallic cores. Though Mars, possibly the Moon and some meteorite parent bodies hosted active magnetic field generation in the past. Dynamo action requires sources of thermal and/or compositional buoyancy capable of driving sufficient convective motions. Modeling has shown that thermal buoyancy, the result of core cooling, typically is incapable of driving the necessary convection by itself. On Earth, compositional buoyancy is thought to derive from crystallization of the inner core, which produces a light element enriched fluid at the inner core boundary. In smaller bodies the crystallization behavior and resulting compositional buoyancy may be quite different, depending on pressure and the identity of the light alloying component(s) in the core. The last decade has seen an explosion in knowledge of the physical and thermodynamic properties of candidate core forming materials. These advances have led to the recognition of an array of possible core crystallization sequences, each with potentially important consequences for planetary evolution and magnetic field generation. For example, the melting behavior of iron-sulfur alloys at pressures up to ~40 GPa suggests that iron "snow" would precipitate in shallow regions of the cores of Ganymede, Mars and Mercury, if sulfur is the dominant light alloying element. Similarly, experiments on the iron-carbon system also suggest shallow precipitation of iron at some pressures. While shallow precipitation of iron snow can provide a buoyancy source for core convection, it can also lead to compositional gradients capable of modifying the scale of, or even suppressing, convection. Liquid immiscibility could also have an influence on convection and magnetic field generation in planetary cores that contain more than one light alloying element. The modest pressures and temperatures in

  18. Planetary Radio Interferometry and Doppler Experiment (PRIDE) for Planetary Atmospheric Studies

    NASA Astrophysics Data System (ADS)

    Bocanegra Bahamon, Tatiana; Cimo, Giuseppe; Duev, Dmitry; Gurvits, Leonid; Molera Calves, Guifre; Pogrebenko, Sergei

    2015-04-01

    The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a technique that allows the determination of the radial velocity and lateral coordinates of planetary spacecraft with very high accuracy (Duev, 2012). The setup of the experiment consists of several ground stations from the European VLBI Network (EVN) located around the globe, which simultaneously perform Doppler tracking of a spacecraft carrier radio signal, and are subsequently processed in a VLBI-style in phase referencing mode. Because of the accurate examination of the changes in phase and amplitude of the radio signal propagating from the spacecraft to the multiple stations on Earth, the PRIDE technique can be used for several fields of planetary research, among which planetary atmospheric studies, gravimetry and ultra-precise celestial mechanics of planetary systems. In the study at hand the application of this technique for planetary atmospheric investigations is demonstrated. As a test case, radio occultation experiments were conducted with PRIDE having as target ESA's Venus Express, during different observing sessions with multiple ground stations in April 2012 and March 2014. Once each of the stations conducts the observation, the raw data is delivered to the correlation center at the Joint Institute for VLBI in Europe (JIVE) located in the Netherlands. The signals are processed with a high spectral resolution and phase detection software package from which Doppler observables of each station are derived. Subsequently the Doppler corrected signals are correlated to derive the VLBI observables. These two sets of observables are used for precise orbit determination. The reconstructed orbit along with the Doppler observables are used as input for the radio occultation processing software, which consists of mainly two modules, the geometrical optics module and the ray tracing inversion module, from which vertical density profiles, and subsequently, temperature and pressure profiles of Venus

  19. Lunar and Planetary Science XXXV: Impact Experiments

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This document covers the following topics: The Shock Compression Laboratory at Harvard: A New Facility for Planetary Impact Processes; What Controls the Intensity of Impact-induced Luminescence?; Isolating the Ricochet-induced Vaporization Process; An Experimental Study of Excavation Flow in Impact Cratering; Migration of the Cratering Flow-Field Center with Implications for Scaling Oblique Impacts; Raman Spectroscopy of Olivine in Dunite Experimentally Shocked to Pressures Between 5 and 59 GPa; and An Experimental Tomography Study of Impact-induced Damage Beneath Craters.

  20. Approaching the Petrophysics of deep Earth's and Earth-like Planetary Interior

    NASA Astrophysics Data System (ADS)

    Mueller, H. J.; Lauterjung, J.; Lathe, C.

    2015-12-01

    The Earth's deep interior is only accessible by indirect methods, first and foremost seismological studies. The interpretation of these seismic data and the corresponding numerical modelling require measurements of the elastic and inelastic properties of representative Earth materials under experimental simulated in-situ pressure-temperature conditions. Seismic tomography studies and corresponding numerical models have demonstrated that under certain conditions subducting slabs can even reach the core mantle boundary. That means former crustal rocks became heavily overprinted by increasing pressure, temperature, deformation and partial material exchange. Because there is no known geodynamic mechanism able to bring them back to the surface as a whole, we cannot sample them. But there is no indication to assume they are simpler than their parental rocks - quite the contrary. I think the first-order future challenge for large volume geophysical high pressure research is to measure data for an understanding of the relation between structural and physical properties of these complex polymineral rock-like assemblages. The paper presents the results of petrophysical transient experiments with natural rocks under uppermost mantle conditions and first steps to perform in-situ experiments under deep mantle conditions.

  1. Planetary Science in Higher Education: Ideas and Experiences

    ERIC Educational Resources Information Center

    Kereszturi, Akos; Hyder, David

    2012-01-01

    The paper investigates how planetary science could be integrated into other courses, specifically geography and astronomy, at two universities in Hungary and the UK. We carried out both a classroom course and an online course over several years. The methods used and the experiences gained, including feedback from students and useful examples for…

  2. Electronic and magnetic structures of the postperovskite-type Fe2O3 and implications for planetary magnetic records and deep interiors.

    PubMed

    Shim, Sang-Heon; Bengtson, Amelia; Morgan, Dane; Sturhahn, Wolfgang; Catalli, Krystle; Zhao, Jiyong; Lerche, Michael; Prakapenka, Vitali

    2009-04-01

    Recent studies have shown that high pressure (P) induces the metallization of the Fe(2+)-O bonding, the destruction of magnetic ordering in Fe, and the high-spin (HS) to low-spin (LS) transition of Fe in silicate and oxide phases at the deep planetary interiors. Hematite (Fe(2)O(3)) is an important magnetic carrier mineral for deciphering planetary magnetism and a proxy for Fe in the planetary interiors. Here, we present synchrotron Mössbauer spectroscopy and X-ray diffraction combined with ab initio calculations for Fe(2)O(3) revealing the destruction of magnetic ordering at the hematite --> Rh(2)O(3)-II type (RhII) transition at 70 GPa and 300 K, and then the revival of magnetic ordering at the RhII --> postperovskite (PPv) transition after laser heating at 73 GPa. At the latter transition, at least half of Fe(3+) ions transform from LS to HS and Fe(2)O(3) changes from a semiconductor to a metal. This result demonstrates that some magnetic carrier minerals may experience a complex sequence of magnetic ordering changes during impact rather than a monotonic demagnetization. Also local Fe enrichment at Earth's core-mantle boundary will lead to changes in the electronic structure and spin state of Fe in silicate PPv. If the ultra-low-velocity zones are composed of Fe-enriched silicate PPv and/or the basaltic materials are accumulated at the lowermost mantle, high electrical conductivity of these regions will play an important role for the electromagnetic coupling between the mantle and the core. PMID:19279204

  3. Electronic and magnetic structures of the postperovskite-type Fe2O3 and implications for planetary magnetic records and deep interiors

    PubMed Central

    Shim, Sang-Heon; Bengtson, Amelia; Morgan, Dane; Sturhahn, Wolfgang; Catalli, Krystle; Zhao, Jiyong; Lerche, Michael; Prakapenka, Vitali

    2009-01-01

    Recent studies have shown that high pressure (P) induces the metallization of the Fe2+–O bonding, the destruction of magnetic ordering in Fe, and the high-spin (HS) to low-spin (LS) transition of Fe in silicate and oxide phases at the deep planetary interiors. Hematite (Fe2O3) is an important magnetic carrier mineral for deciphering planetary magnetism and a proxy for Fe in the planetary interiors. Here, we present synchrotron Mössbauer spectroscopy and X-ray diffraction combined with ab initio calculations for Fe2O3 revealing the destruction of magnetic ordering at the hematite → Rh2O3-II type (RhII) transition at 70 GPa and 300 K, and then the revival of magnetic ordering at the RhII → postperovskite (PPv) transition after laser heating at 73 GPa. At the latter transition, at least half of Fe3+ ions transform from LS to HS and Fe2O3 changes from a semiconductor to a metal. This result demonstrates that some magnetic carrier minerals may experience a complex sequence of magnetic ordering changes during impact rather than a monotonic demagnetization. Also local Fe enrichment at Earth's core-mantle boundary will lead to changes in the electronic structure and spin state of Fe in silicate PPv. If the ultra-low-velocity zones are composed of Fe-enriched silicate PPv and/or the basaltic materials are accumulated at the lowermost mantle, high electrical conductivity of these regions will play an important role for the electromagnetic coupling between the mantle and the core. PMID:19279204

  4. Traverse Planning Experiments for Future Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Hoffman, Stephen J.; Voels, Stephen A.; Mueller, Robert P.; Lee, Pascal C.

    2012-01-01

    The purpose of the investigation is to evaluate methodology and data requirements for remotely-assisted robotic traverse of extraterrestrial planetary surface to support human exploration program, assess opportunities for in-transit science operations, and validate landing site survey and selection techniques during planetary surface exploration mission analog demonstration at Haughton Crater on Devon Island, Nunavut, Canada. Additionally, 1) identify quality of remote observation data sets (i.e., surface imagery from orbit) required for effective pre-traverse route planning and determine if surface level data (i.e., onboard robotic imagery or other sensor data) is required for a successful traverse, and if additional surface level data can improve traverse efficiency or probability of success (TRPF Experiment). 2) Evaluate feasibility and techniques for conducting opportunistic science investigations during this type of traverse. (OSP Experiment). 3) Assess utility of remotely-assisted robotic vehicle for landing site validation survey. (LSV Experiment).

  5. Planetary Resources and Astroecology. Planetary Microcosm Models of Asteroid and Meteorite Interiors: Electrolyte Solutions and Microbial Growth- Implications for Space Populations and Panspermia

    NASA Astrophysics Data System (ADS)

    Mautner, Michael N.

    2002-03-01

    Planetary microcosms were constructed using extracts from meteorites that simulate solutions in the pores of carbonaceous chondrites. The microcosms were found to support the growth of complex algal and microbial populations. Such astroecology experiments demonstrate how a diverse ecosystem could exist in fluids within asteroids, and in meteorites that land on aqueous planets. The microcosm solutions were obtained by extracting nutrient electrolytes under natural conditions from powders of the Allende (CV3) and Murchison (CM2) meteorites at low (0.02 g/ml) and high (10.0 g/ml) solid/solution ratios. The latter solutions contain >3 mol/L electrolytes and about 10 g/L organics, that simulate natural fluids in asteroids during aqueous alteration and in the pores of meteorites, which can help prebiotic synthesis and the survival of early microorganisms. These solutions and wet solids were in fact found to support complex self-sustaining microbial communities with populations of 4 × 105 algae and 6 × 106 bacteria and fungi for long periods (>8 months). The results show that planetary microcosms based on meteorites can: assay the fertilities of planetary materials; identify space bioresources; target astrobiology exploration; and model past and future space-based ecosystems. The results show that bioresources in the carbonaceous asteroids can sustain a biomass of 1018 kg, comprising 1032 microorganisms and a human population of 1014. The results also suggest that protoplanetary nebulae can support and disperse microorganisms and can be therefore effective environments for natural and directed panspermia.

  6. Chemical differentiation of a convecting planetary interior: Consequences for a one-plate planet such as Venus

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    Chemically depleted mantle forming a buoyant, refractory layer at the top of the mantle can have important implications for the evolution of the interior and surface. On Venus, the large apparent depths of compensation for surface topographic features might be explained if surface topography were supported by variations in the thickness of a 100-200 km thick chemically buoyant mantle layer or by partial melting in the mantle at the base of such a layer. Long volcanic flows seen on the surface may be explained by deep melting that generates low-viscosity MgO-rich magmas. The presence of a shallow refractory mantle layer may also explain the lack of volcanism associated with rifting. As the depleted layer thickens and cools, it becomes denser than the convecting interior and the portion of it that is hot enough to flow can mix with the convecting mantle. Time dependence of the thickness of a depleted layer may create episodic resurfacing events as needed to explain the observed distribution of impact craters on the venusian surface. We consider a planetary structure consisting of a crust, depleted mantle layer, and a thermally and chemically well-mixed convecting mantle. The thermal evolution of the convecting spherical planetary interior is calculated using energy conservation: the time rate of change of thermal energy in the interior is equated to the difference in the rate of radioactive heat production and the rate of heat transfer across the thermal boundary layer. Heat transfer across the thermal boundary layer is parameterized using a standard Nusselt number-Rayleigh number relationship. The radioactive heat production decreases with time corresponding to decay times for the U, Th, and K. The planetary interior cools by the advection of hot mantle at temperature T interior into the thermal boundary layer where it cools conductively. The crust and depleted mantle layers do not convect in our model so that a linear conductive equilibrium temperature distribution

  7. Phase Diagram and Physical Properties of H[subscript 2]O at High Pressures and temperatures: Applications to Planetary Interiors

    SciTech Connect

    Lin, Jung-Fu; Schwegler, Eric; Yoo, Choong-Shik

    2007-02-22

    Here we discuss the phase diagram and physical properties of H{sub 2}O under pressure-temperature conditions relevant to planetary interiors. Recent studies show that the melting curve of H{sub 2}O increases rapidly above a recently discovered triple point at approximately 35 to 47 GPa and 1000 K, indicating a large increase in {Delta}V/{Delta}S (volume versus entropy change) and associated changes in the physical properties of H{sub 2}O at high pressures and temperatures. Existence of the triple point is thought to be associated with the formation of a superionic phase, dynamically-disordered ice VII, or extension of the ice VII-ice X phase boundary; although the precise pressure and temperature of the triple point, curvature of the melting line, and nature of the solid-solid transition below the triple point all remain to be further explored. The steep increase in the melting curve of H{sub 2}O at high pressures and temperatures has important implications on our understanding of planetary interiors. Depending on its curvature, the melting line of H{sub 2}O may intersect the isentropes of Neptune and Uranus as well as the geotherm of Earth's lower mantle. Furthermore, if the triple point is due to the occurrence of the theoretically predicted superionic phase, besides leading to significant ionic conductivity, fast proton diffusion would cause enhanced chemical reactivity and formation of complex compounds in these planets. For example, reaction of H{sub 2}O with iron and other metals to form metal hydrides such as FeH{sub x} could provide a mechanism for incorporation of hydrogen as a light element into Earth's core. The equation of state of water is also presented as it pertains to the properties of hydrous fluid and melt phases in the mantle.

  8. Little Earth Experiment: An instrument to model planetary cores

    NASA Astrophysics Data System (ADS)

    Aujogue, Kélig; Pothérat, Alban; Bates, Ian; Debray, François; Sreenivasan, Binod

    2016-08-01

    In this paper, we present a new experimental facility, Little Earth Experiment, designed to study the hydrodynamics of liquid planetary cores. The main novelty of this apparatus is that a transparent electrically conducting electrolyte is subject to extremely high magnetic fields (up to 10 T) to produce electromagnetic effects comparable to those produced by moderate magnetic fields in planetary cores. This technique makes it possible to visualise for the first time the coupling between the principal forces in a convection-driven dynamo by means of Particle Image Velocimetry (PIV) in a geometry relevant to planets. We first present the technology that enables us to generate these forces and implement PIV in a high magnetic field environment. We then show that the magnetic field drastically changes the structure of convective plumes in a configuration relevant to the tangent cylinder region of the Earth's core.

  9. Little Earth Experiment: An instrument to model planetary cores.

    PubMed

    Aujogue, Kélig; Pothérat, Alban; Bates, Ian; Debray, François; Sreenivasan, Binod

    2016-08-01

    In this paper, we present a new experimental facility, Little Earth Experiment, designed to study the hydrodynamics of liquid planetary cores. The main novelty of this apparatus is that a transparent electrically conducting electrolyte is subject to extremely high magnetic fields (up to 10 T) to produce electromagnetic effects comparable to those produced by moderate magnetic fields in planetary cores. This technique makes it possible to visualise for the first time the coupling between the principal forces in a convection-driven dynamo by means of Particle Image Velocimetry (PIV) in a geometry relevant to planets. We first present the technology that enables us to generate these forces and implement PIV in a high magnetic field environment. We then show that the magnetic field drastically changes the structure of convective plumes in a configuration relevant to the tangent cylinder region of the Earth's core. PMID:27587138

  10. Trace elements as quantitative probes of differentiation processes in planetary interiors

    SciTech Connect

    Drake, M.J.

    1980-02-01

    Abundances of trace elements in extrusive igneous rocks may be used as petrological and geochemical probes of the source regions of the rocks if differentiation processes, partition coefficients, phase equilibria, and initial concentrations in the source region are known. The characteristic trace element signature that each mineral in the source region imparts on the magma forms the conceptual basis for trace element modeling. The task of the trace element geochemist is to solve mathematically the inverse problem. Given trace element abundances in a magma, what is the ode of its source region. The most successful modeling has been performed for small planetary bodies which underwent relatively simple igneous differentiation events. An example is the eucrite parent body, a planet which produced basals at approx. =4.6 Gy. and has been quiescent ever since. This simple differentiation history permits the calculation of its bulk composition (a feldspathic peridotite) and has led to the tentative identification of asteroid 4 Westa as the eucrite parent body. The differentiation of iron meteorite groups in parent body cores is amenable to similar treatment. The 'anomalous' behavior of Cr, suggests that IIIA, B irons and main group pallasites equilibrated with troilite, spinel, ferromagnesian silicates, or some combination thereof. The moon has undergone more complex differentiation, and quantitative geochemical modeling is correspondingly more difficult. Nevertheless, modeling the two-stage evolution of mare basals raises the possibility that the primordial moon did not have chondritic relative abundances of such refractory elements as Ca, Al, U, and the rare-earth elements. The nonchondritic element ratios are characteristic of planetary, not nebular, fractionation processes and are consistent with the derivation of the moon from a precursor planet, possibly the earth.

  11. Experiments in Planetary and Related Sciences and the Space Station

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald (Editor); Williams, Richard J. (Editor)

    1987-01-01

    Numerous workshops were held to provide a forum for discussing the full range of possible experiments, their science rationale, and the requirements on the Space Station, should such experiments eventually be flown. During the workshops, subgroups met to discuss areas of common interest. Summaries of each group and abstracts of contributed papers as they developed from a workshop on September 15 to 16, 1986, are included. Topics addressed include: planetary impact experimentation; physics of windblown particles; particle formation and interaction; experimental cosmochemistry in the space station; and an overview of the program to place advanced automation and robotics on the space station.

  12. Experiments in Planetary and Related Sciences and the Space Station

    SciTech Connect

    Greeley, R.; Williams, R.J.

    1987-11-01

    Numerous workshops were held to provide a forum for discussing the full range of possible experiments, their science rationale, and the requirements on the Space Station, should such experiments eventually be flown. During the workshops, subgroups met to discuss areas of common interest. Summaries of each group and abstracts of contributed papers as they developed from a workshop on September 15 to 16, 1986, are included. Topics addressed include: planetary impact experimentation; physics of windblown particles; particle formation and interaction; experimental cosmochemistry in the space station; and an overview of the program to place advanced automation and robotics on the space station.

  13. Planetary resources and astroecology. Planetary microcosm models of asteroid and meteorite interiors: electrolyte solutions and microbial growth--implications for space populations and panspermia.

    PubMed

    Mautner, Michael N

    2002-01-01

    Planetary microcosms were constructed using extracts from meteorites that simulate solutions in the pores of carbonaceous chondrites. The microcosms were found to support the growth of complex algal and microbial populations. Such astroecology experiments demonstrate how a diverse ecosystem could exist in fluids within asteroids, and in meteorites that land on aqueous planets. The microcosm solutions were obtained by extracting nutrient electrolytes under natural conditions from powders of the Allende (CV3) and Murchison (CM2) meteorites at low (0.02 g/ml) and high (10.0 g/ml) solid/solution ratios. The latter solutions contain > 3 mol/L electrolytes and about 10 g/L organics, that simulate natural fluids in asteroids during aqueous alteration and in the pores of meteorites, which can help prebiotic synthesis and the survival of early microorganisms. These solutions and wet solids were in fact found to support complex self-sustaining microbial communities with populations of 4 x 10(5) algae and 6 x 10(6) bacteria and fungi for long periods (> 8 months). The results show that planetary microcosms based on meteorites can: assay the fertilities of planetary materials; identify space bioresources; target astrobiology exploration; and model past and future space-based ecosystems. The results show that bioresources in the carbonaceous asteroids can sustain a biomass of 10(18) kg, comprising 10(32) microorganisms and a human population of 10(14). The results also suggest that protoplanetary nebulae can support and disperse microorganisms and can be therefore effective environments for natural and directed panspermia. PMID:12449855

  14. Venus as a laboratory for studying planetary surface, interior, and atmospheric evolution

    NASA Astrophysics Data System (ADS)

    Smrekar, S. E.; Hensley, S.; Helbert, J.

    2013-12-01

    As Earth's twin, Venus offers a laboratory for understanding what makes our home planet unique in our solar system. The Decadal Survey points to the role of Venus in answering questions such as the supply of water and its role in atmospheric evolution, its availability to support life, and the role of geology and dynamics in controlling volatiles and climate. On Earth, the mechanism of plate tectonics drives the deformation and volcanism that allows volatiles to escape from the interior to the atmosphere and be recycled into the interior. Magellan revealed that Venus lacks plate tectonics. The number and distribution of impact craters lead to the idea Venus resurfaced very rapidly, and inspired numerous models of lithospheric foundering and episodic plate tectonics. However we have no evidence that Venus ever experienced a plate tectonic regime. How is surface deformation affected if no volatiles are recycled into the interior? Although Venus is considered a ';stagnant' lid planet (lacking plate motion) today, we have evidence for recent volcanism. The VIRTIS instrument on Venus Express mapped the southern hemisphere at 1.02 microns, revealing areas likely to be unweathered, recent volcanic flows. Additionally, numerous studies have shown that the crater population is consistent with ongoing, regional resurfacing. How does deformation and volcanism occur in the absence of plates? At what rate is the planet resurfacing and thus outgassing? Does lithospheric recycling occur with plate tectonics? In the 25 years since Magellan, the design of Synthetic Aperture Radar has advanced tremendously, allowing order of magnitude improvements in altimetry and imaging. With these advanced tools, we can explore Venus' past and current tectonic states. Tesserae are highly deformed plateaus, thought to be possible remnants of Venus' earlier tectonic state. How did they form? Are they low in silica, like Earth's continents, indicating the presence of abundant water? Does the plains

  15. Opacity and conductivity measurements in noble gases at conditions of planetary and stellar interiors

    PubMed Central

    McWilliams, R. Stewart; Dalton, D. Allen; Konôpková, Zuzana; Mahmood, Mohammad F.; Goncharov, Alexander F.

    2015-01-01

    The noble gases are elements of broad importance across science and technology and are primary constituents of planetary and stellar atmospheres, where they segregate into droplets or layers that affect the thermal, chemical, and structural evolution of their host body. We have measured the optical properties of noble gases at relevant high pressures and temperatures in the laser-heated diamond anvil cell, observing insulator-to-conductor transformations in dense helium, neon, argon, and xenon at 4,000–15,000 K and pressures of 15–52 GPa. The thermal activation and frequency dependence of conduction reveal an optical character dominated by electrons of low mobility, as in an amorphous semiconductor or poor metal, rather than free electrons as is often assumed for such wide band gap insulators at high temperatures. White dwarf stars having helium outer atmospheres cool slower and may have different color than if atmospheric opacity were controlled by free electrons. Helium rain in Jupiter and Saturn becomes conducting at conditions well correlated with its increased solubility in metallic hydrogen, whereas a deep layer of insulating neon may inhibit core erosion in Saturn. PMID:26080401

  16. Opacity and conductivity measurements in noble gases at conditions of planetary and stellar interiors.

    PubMed

    McWilliams, R Stewart; Dalton, D Allen; Konôpková, Zuzana; Mahmood, Mohammad F; Goncharov, Alexander F

    2015-06-30

    The noble gases are elements of broad importance across science and technology and are primary constituents of planetary and stellar atmospheres, where they segregate into droplets or layers that affect the thermal, chemical, and structural evolution of their host body. We have measured the optical properties of noble gases at relevant high pressures and temperatures in the laser-heated diamond anvil cell, observing insulator-to-conductor transformations in dense helium, neon, argon, and xenon at 4,000-15,000 K and pressures of 15-52 GPa. The thermal activation and frequency dependence of conduction reveal an optical character dominated by electrons of low mobility, as in an amorphous semiconductor or poor metal, rather than free electrons as is often assumed for such wide band gap insulators at high temperatures. White dwarf stars having helium outer atmospheres cool slower and may have different color than if atmospheric opacity were controlled by free electrons. Helium rain in Jupiter and Saturn becomes conducting at conditions well correlated with its increased solubility in metallic hydrogen, whereas a deep layer of insulating neon may inhibit core erosion in Saturn. PMID:26080401

  17. Lunar and Planetary Science XXXV: Viewing the Lunar Interior Through Titanium-Colored Glasses

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The session"Viewing the Lunar Interior Through Titanium-Colored Glasses" included the following reports:Consequences of High Crystallinity for the Evolution of the Lunar Magma Ocean: Trapped Plagioclase; Low Abundances of Highly Siderophile Elements in the Lunar Mantle: Evidence for Prolonged Late Accretion; Fast Anorthite Dissolution Rates in Lunar Picritic Melts: Petrologic Implications; Searching the Moon for Aluminous Mare Basalts Using Compositional Remote-Sensing Constraints II: Detailed analysis of ROIs; Origin of Lunar High Titanium Ultramafic Glasses: A Hybridized Source?; Ilmenite Solubility in Lunar Basalts as a Function of Temperature and Pressure: Implications for Petrogenesis; Garnet in the Lunar Mantle: Further Evidence from Volcanic Glasses; Preliminary High Pressure Phase Relations of Apollo 15 Green C Glass: Assessment of the Role of Garnet; Oxygen Fugacity of Mare Basalts and the Lunar Mantle. Application of a New Microscale Oxybarometer Based on the Valence State of Vanadium; A Model for the Origin of the Dark Ring at Orientale Basin; Petrology and Geochemistry of LAP 02 205: A New Low-Ti Mare-Basalt Meteorite; Thorium and Samarium in Lunar Pyroclastic Glasses: Insights into the Composition of the Lunar Mantle and Basaltic Magmatism on the Moon; and Eu2+ and REE3+ Diffusion in Enstatite, Diopside, Anorthite, and a Silicate Melt: A Database for Understanding Kinetic Fractionation of REE in the Lunar Mantle and Crust.

  18. Traverse Planning Experiments for Future Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Hoffman, S. J.; Voels, S. A.; Mueller, R. P.; Lee, P. C.

    2011-01-01

    This paper describes the results of a recent (July-August 2010 and July 2011) planetary surface traverse planning experiment. The purpose of this experiment was to gather data relevant to robotically repositioning surface assets used for planetary surface exploration. This is a scenario currently being considered for future human exploration missions to the Moon and Mars. The specific scenario selected was a robotic traverse on the lunar surface from an outpost at Shackleton Crater to the Malapert Massif. As these are exploration scenarios, the route will not have been previously traversed and the only pre-traverse data sets available will be remote (orbital) observations. Devon Island was selected as an analog location where a traverse route of significant length could be planned and then traveled. During the first half of 2010, a team of engineers and scientists who had never been to Devon Island used remote sensing data comparable to that which is likely to be available for the Malapert region (eg., 2-meter/pixel imagery, 10-meter interval topographic maps and associated digital elevation models, etc.) to plan a 17-kilometer (km) traverse. Surface-level imagery data was then gathered on-site that was provided to the planning team. This team then assessed whether the route was actually traversable or not. Lessons learned during the 2010 experiment were then used in a second experiment in 2011 for which a much longer traverse (85 km) was planned and additional surface-level imagery different from that gathered in 2010 was obtained for a comparative analysis. This paper will describe the route planning techniques used, the data sets available to the route planners and the lessons learned from the two traverses planned and carried out on Devon Island.

  19. Planetary radio astronomy receiver. [experiment on Voyager spacecraft

    NASA Technical Reports Server (NTRS)

    Lang, G. J.; Peltzer, R. G.

    1977-01-01

    The planetary radio astronomy (PRA) experiment on the Voyager spacecraft will measure the amplitude, spectrum, time variations, and polarization of radio emissions over a frequency range of 1.2 kHz to 40.5 MHz with the aid of the PRA receiver (PRAR) and two 10-m orthogonal monopoles. Sensitivity and dynamic range will allow observation of a wide range of Jovian emissions from near earth to encounter. This paper describes the system elements, including the preamp/attenuator/calibrator, the LF polarization discriminator, the four LF-IF amplifier stages, the HF polarization discriminator, the translation LO, the log-IF and detector, the frequency synthesizer, the data processor, control system, power supply, and antennas.

  20. Planetary missions as lab experiments in the introductory classroom

    NASA Astrophysics Data System (ADS)

    Collins, G. C.

    2011-12-01

    As is the case at many liberal arts colleges, at Wheaton we require all of our students to take a class in the natural sciences. Our introductory classes must include some type of experimental or laboratory component that allows students to directly experience the scientific cycle of asking a question, collecting data, and analyzing the data to either answer the question or to ask new ones. We want them to use their creativity and deal with ambiguity, so they can break out of the idea that science is something that is already written down in a book. This can be a challenge in planetary science, which draws on so many different disciplines and has so many targets of interest that one could spend the entire semester on background material without getting to the experiment cycle. For the past several years, I have been developing a structure for integrating experimentation into the introductory planetary science classroom, alongside some of the more traditional background material. We spend the first half of the semester getting used to asking questions about planets, and then finding and using simple types of data that have already been collected by spacecraft to answer those questions. Along the way, we track a current planetary mission to examine the questions it was designed to investigate, and how its instruments work together to address those questions. By the second half of the semester, the students are ready for two more challenging group projects. In the first project, the class (36 students) is divided in half, and each group must write a plan for the first day of operations of a robotic rover. The opposite group then goes out to an undisclosed field location and collects the data according to the first group's operations plan. After the field trips, the groups receive the data back from their rovers, still without knowing exactly where they landed, and have to hold a press conference discussing the important scientific discoveries at their landing site

  1. Using a Field Experience to Build Understanding of Planetary Geology

    NASA Astrophysics Data System (ADS)

    Higbie, M.; Treiman, A.; Kiefer, W.; Shipp, S.

    2004-12-01

    In the summer of 2004, the Lunar and Planetary Institute hosted 25 middle- and high-school teachers on a week-long field experience in Idaho and Montana. This workshop mixed field work with classroom experiences and provided educators and scientists the opportunity to interact. The educators investigated deposits associated with Glacial Lake Missoula floods and lava flows in the Craters of the Moon National Monument and Preserve. The participants applied what they learned about Earth-based processes to develop understanding of processes operating on Mars and the most recent results from NASA's missions to Mars. This was the most recent of five field-based experiences that used Earth-planet comparisons as a basis for experiential learning. These field experiences all are designed to strengthen content knowledge of geologic processes and planetary sciences. Learning geology through fieldwork enables participants to take ownership of the content through real-life experience; in essence, the teacher becomes the student. Establishing deeper knowledge of the content increases their confidence in facilitating inquiry-based science in their own classrooms. In addition to content, the educators are immersed in the process of science. Participants make observations, compile notes and illustrations, debate interpretations, draw conclusions, and communicate findings. Care was taken to separate observations and interpretations to help build an understanding of scientific reasoning. Discussions often involved questions without solutions, or with multiple solutions. While some participants expressed discomfort with these aspects of the nature of science, most were more comfortable with open-ended, inquiry based exploration by the close of the workshop. The field work is coupled with discussion and activities in the classroom. Participants reflected on the field sites and placed them in the context of the geologic history of the region. Observations and interpretations at

  2. Insights Into the Dynamics of Planetary Interiors Obtained Through the Study of Global Distribution of Volcanoes III: Lessons From Io.

    NASA Astrophysics Data System (ADS)

    Canon-Tapia, E.; Hamilton, C.; Lopes, R. M. C.

    2015-12-01

    Clues concerning dynamic aspects of planetary interiors can be obtained through the characterization of volcano distribution at a global scale. On past years, results obtained from global distribution of volcanism on Earth and Venus have been presented, and compared with each other. In this work, the global distribution of volcanism on Io (the innermost of Jupiter's Galilean satellites and the most volcanically active body in the Solar System) is explored using the same tools. Volcanic centers on Io can be divided in two groups: The first including positive thermal anomalies, or hotspots, and the second formed by volcano-tectonic depressions called paterae. Approximately 20% of the documented patera coincide with hotspots, but not all of Io's current volcanic activity is directly associated to paterae. It is uncertain whether hotspots located outside paterae represent volcanic systems still lacking a caldera-like structure, or they represent an entirely different type of volcanism. To account for this source of uncertainty, the analysis reported here was completed on different databases (hotspots, paterae, patera floor units and a combination of hotspots and paterae referred to as volcanic systems). In addition, the distribution of Io's mountains also was studied. As a result, we show that the main clusters of volcanism on Io support the existence of mantle convection patterns that include a combined heating between the astenosphere and the deep mantle (with the former source being more important, but not necessarily on a 2:1 proportion), takes place at moderate to high Reynolds numbers, and includes some degree of impermeability between the astenosphere and the mantle. We also show that although the long-wavelength volcano distribution is controlled by the patterns of mantle convection, the astenosphere serves as a buffer zone where magma is distributed laterally giving place to volcanic activity away from the zones of influence of the hot mantle isotherms. The

  3. Response of Mercury's Magnetosphere to Solar Wind Forcing: Results of Global MHD Simulations with Coupled Planetary Interior

    NASA Astrophysics Data System (ADS)

    Jia, Xianzhe; Slavin, James; Poh, Gangkai; Toth, Gabor; Gombosi, Tamas

    2016-04-01

    As the innermost planet, Mercury arguably undergoes the most direct space weathering interactions due to its weak intrinsic magnetic field and its close proximity to the Sun. It has long been suggested that two processes, i.e., erosion of the dayside magnetosphere due to intense magnetopause reconnection and the shielding effect of the induction currents generated at the conducting core, compete against each other in governing the large-scale structure of Mercury's magnetosphere. An outstanding question concerning Mercury's space weather is which of the two processes is more important. To address this question, we have developed a global MHD model in which Mercury's interior is electromagnetically coupled to the surrounding space environment. As demonstrated in Jia et al. (2015), the new modeling capability allows for self-consistently characterizing the dynamical response of the Mercury system to time-varying external conditions. To assess the relative importance of induction and magnetopause reconnection in controlling the magnetospheric configuration, especially under strong solar driving conditions, we have carried out multiple global simulations that adopt a wide range of solar wind dynamic pressure and IMF conditions. We find that, while the magnetopause standoff distance decreases with increasing solar wind pressure, just as expected, its dependence on the solar wind pressure follows closely a power-law relationship with an index of ~ -1/6, rather than a steeper power-law falling-off expected for the case with only induction present. This result suggests that for the range of solar wind conditions examined, the two competing processes, namely induction and reconnection, appear to play equally important roles in determining the global configuration of Mercury's magnetosphere, consistent with the finding obtained by Slavin et al. (2014) based on MESSENGER observations. We also find that the magnetic perturbations produced by the magnetospheric current systems

  4. The SCITEAS experiment: Optical characterizations of sublimating icy planetary analogues

    NASA Astrophysics Data System (ADS)

    Pommerol, A.; Jost, B.; Poch, O.; El-Maarry, M. R.; Vuitel, B.; Thomas, N.

    2015-05-01

    We have designed and built a laboratory facility to investigate the spectro-photometric and morphologic properties of different types of ice-bearing planetary surface analogs and follow their evolution upon exposure to a low pressure and low temperature environment. The results obtained with this experiment are used to verify and improve our interpretations of current optical remote-sensing datasets. They also provide valuable information for the development and operation of future optical instruments. The Simulation Chamber for Imaging the Temporal Evolution of Analogue Samples (SCITEAS) is a small thermal vacuum chamber equipped with a variety of ports and feedthroughs that permit both in-situ and remote characterizations as well as interacting with the sample. A large quartz window located directly above the sample is used to observe its surface from outside with a set of visible and near-infrared cameras. The sample holder can be easily and quickly inserted and removed from the chamber and is compatible with the other measurement facilities of the Laboratory for Outflow Studies of Sublimating Materials (LOSSy) at the University of Bern. We report here on the results of two of the first experiments performed in the SCITEAS chamber. In the first experiment, fine-grained water ice mixed with dark organic and mineral matter was left to sublime in vacuum and at low temperature, simulating the evolution of the surface of a comet nucleus approaching the Sun. We observed and characterized the formation and evolution of a crust of refractory organic and mineral matter at the surface of the sample and linked the evolution of its structure and texture to its spectro-photometric properties. In the second experiment, a frozen soil was prepared by freezing a mixture of smectite mineral and water. The sample was then left to sublime for 6 h to simulate the loss of volatiles from icy soil at high latitudes on Mars. Colour images were produced using the definitions of the

  5. Infrared experiments for spaceborne planetary atmospheres research. Full report

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The role of infrared sensing in atmospheric science is discussed and existing infrared measurement techniques are reviewed. Proposed techniques for measuring planetary atmospheres are criticized and recommended instrument developments for spaceborne investigations are summarized for the following phenomena: global and local radiative budget; radiative flux profiles; winds; temperature; pressure; transient and marginal atmospheres; planetary rotation and global atmospheric activity; abundances of stable constituents; vertical, lateral, and temporal distribution of abundances; composition of clouds and aerosols; radiative properties of clouds and aerosols; cloud microstructure; cloud macrostructure; and non-LTE phenomena.

  6. High pressure cosmochemistry of major planetary interiors: Laboratory studies of the water-rich region of the system ammonia-water

    NASA Technical Reports Server (NTRS)

    Nicol, Malcolm; Johnson, Mary; Boone, Steven; Cynn, Hyunchee

    1987-01-01

    Several studies relative to high pressure cosmochemistry of major planetary interiors are summarized. The behavior of gas-ice mixtures at very high pressures, studies of the phase diagram of (NH3) sub x (H2O) sub 1-x at pressures to 5GPa and temperatures from 240 to 370 K, single crystal growth of ammonia dihydrate at room temperature in order to determine their structures by x-ray diffraction, spectroscopy of chemical reactions during shock compression in order to evaluate how the reactions affect the interpretation of equation of state data obtained by shock methods, and temperature and x-ray diffraction measurements made on resistively heated wire in diamond anvil cells in order to obtain phase and structural data relevant to the interiors of terrestrial planets are among the studies discussed.

  7. Infrared experiments for spaceborne planetary atmospheres research. Executive summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The role of 0.5 to 300 micron remote sensing in planetary atmospheres exploration was evaluated by examining a broad range of measurement techniques including quantitative intercomparisons of existing and planned instruments by the phenomenological method. Key areas of infrared instrumentation requiring development for the investigations of atmospheres were identified.

  8. High-energy density experiments on planetary materials using high-power lasers and X-ray free electron laser

    NASA Astrophysics Data System (ADS)

    Ozaki, Norimasa

    2015-06-01

    Laser-driven dynamic compression allows us to investigate the behavior of planetary and exoplanetary materials at extreme conditions. Our high-energy density (HED) experiments for applications to planetary sciences began over five years ago. We measured the equation-of-state of cryogenic liquid hydrogen under laser-shock compression up to 55 GPa. Since then, various materials constituting the icy giant planets and the Earth-like planets have been studied using laser-driven dynamic compression techniques. Pressure-volume-temperature EOS data and optical property data of water and molecular mixtures were obtained at the planetary/exoplanetary interior conditions. Silicates and oxides data show interesting behaviors in the warm-dense matter regime due to their phase transformations. Most recently the structural changes of iron were observed for understanding the kinetics under the bcc-hcp transformation phenomena on a new HED science platform coupling power-lasers and the X-ray free electron laser (SACLA). This work was performed under the joint research project at the Institute of Laser Engineering, Osaka University. It was partially supported by a Grant-in-Aid for Scientific Research (Grant Nos. 20654042, 22224012, 23540556, and 24103507) and also by grants from the Core-to-Core Program of JSPS on International Alliance for Material Science in Extreme States with High Power Laser and XFEL, and the X-ray Free Electron Laser Priority Strategy Program of MEXT.

  9. Impact experiments related to the evolution of planetary regoliths

    NASA Astrophysics Data System (ADS)

    Horz, Friedrich; Cintala, Mark

    1997-03-01

    Impact induced comminution of planetary surfaces is pervasive throughout the solar system and occurs on sub-millimeter to global-scales, resulting in comminution products that range from fine grained surface soils, to massive, polymict ejecta deposits, to collisionally fragmented objects. Within this wide range of comminution products we define regoliths in a narrow sense as materials that were processed by repetitive impacts to dimensional scales comparable to or smaller than that of component minerals of the progenitor rock(s). We summarize in this paper a wide variety of impact experiments and other observations that were primarily intended to understand the evolution of regoliths on lunar basalt flows, and we discuss some of their implications for asteroidal surfaces. Cratering experiments in both rock and non-cohesive materials, combined with photogeologic observations of the lunar surface, demonstrate that craters < 500 m in diameter contribute most to the excavation of local bedrock for subsequent processing by micrometeorites. The overall excavation rate, and thus, growth rate of the debris layer decreases with time, because the increasingly thicker fragmental layer will prevent progressively larger projectiles from reaching bedrock. Typical growth rates for a 5 m thick lunar soil layer are initially (approximately > 3 Ga ago) a few mm/my and slowed to < 1 mm/Ma at present. The coarse grained crater ejecta are efficiently comminuted by collisional fragmentation processes and the mean residence time of a 1 kg rock is typically ( 10 Ma. The actual comminution of either lithic or monomineralic detritus is highly mineral specific, with feldspar and mesostasis comminuting preferentially over pyroxene and olivine, thus resulting in mechanically fractionated fines, especially at grain sizes < 20 m. Such fractionated fines also participate preferentially in the shock melting of lunar soils, giving rise to "agglutinate" melts. As a consequence, agglutinate melts are

  10. Accessing Interior Vector Magnetic Field Components in Neutron EDM Experiments via Boundary Value Techniques

    NASA Astrophysics Data System (ADS)

    Plaster, Brad

    2012-10-01

    We propose a new technique for the determination and monitoring of the interior vector magnetic field components during the operation of neutron EDM experiments. If a suitable three-dimensional volume surrounding the fiducial volume of an experiment can be defined which contains no interior currents or magnetization, each of the interior vector field components will satisfy the Laplace Equation within this volume. Therefore, if the field components can be measured on the boundary, the interior vector field components can be determined uniquely via numerical solution of the Laplace Equation. We discuss the applicability of this technique to the determination of the magnetic field components and magnetic field gradients in the fiducial volumes of neutron EDM experiments.

  11. Planetary Surface Instruments Workshop

    NASA Technical Reports Server (NTRS)

    Meyer, Charles (Editor); Treiman, Allan H. (Editor); Kostiuk, Theodor (Editor)

    1996-01-01

    This report on planetary surface investigations and planetary landers covers: (1) the precise chemical analysis of solids; (2) isotopes and evolved gas analyses; (3) planetary interiors; planetary atmospheres from within as measured by landers; (4) mineralogical examination of extraterrestrial bodies; (5) regoliths; and (6) field geology/processes.

  12. Space factor of "excess" heat generation in the Earth and planetary interiors. Article 2. Space-time patterns of distribution of the heat generating zones in the Earth interior

    NASA Astrophysics Data System (ADS)

    Makarenko, O. M.

    Besides radiogenic energy, the "supplementary" energy source occurs in the Earth interior. This source is of cosmic origin and modulated by position and direction of the Solar system motion in the Galaxy. It can be called as "cosmic furnace", which works in the Earth internal and outer cores as well as in mantle. The specific thermal generation per unit of volume is about 10 W/km3 in the Earth mantle and some 50 W/km3 in the Earth core. Excess heat generation occurs mainly in the latitudinal zone between 650 of northern latitude and 650 of southern latitude. More active heat generation occurs in the northern and southern hemispheres alternately with intervals about 200 million years that is equal to the period of revolution about the Galaxy center. The latitudinal zone of maximal heat generation moves in time along the sinusoidal curve in accordance with displacement of projection of the Solar system apex on the Earth surface. Maximal intensity of heat generation occurs when projection of the Earth motion in the Galaxy achieves the Earth equator (every 100 million years). At this particular time the direction of the Solar system motion in the Galaxy is in the plane of ecliptic and heat generation - of maximal intensity. This results in existence of equatorial hot belt in the Earth interior, distinctly exhibited in the core and mantle. The fact of alternate heating of the Earth semi-spheres allows us to assume that heat-generating factor influencing our planet from galactic space is absorbed largely while passing through the planetary interior.

  13. Planetary Magnetism

    NASA Technical Reports Server (NTRS)

    Connerney, J. E. P.

    2007-01-01

    The chapter on Planetary Magnetism by Connerney describes the magnetic fields of the planets, from Mercury to Neptune, including the large satellites (Moon, Ganymede) that have or once had active dynamos. The chapter describes the spacecraft missions and observations that, along with select remote observations, form the basis of our knowledge of planetary magnetic fields. Connerney describes the methods of analysis used to characterize planetary magnetic fields, and the models used to represent the main field (due to dynamo action in the planet's interior) and/or remnant magnetic fields locked in the planet's crust, where appropriate. These observations provide valuable insights into dynamo generation of magnetic fields, the structure and composition of planetary interiors, and the evolution of planets.

  14. Explorations in Teaching Sustainable Design: A Studio Experience in Interior Design/Architecture

    ERIC Educational Resources Information Center

    Gurel, Meltem O.

    2010-01-01

    This article argues that a design studio can be a dynamic medium to explore the creative potential of the complexity of sustainability from its technological to social ends. The study seeks to determine the impact of an interior design/architecture studio experience that was initiated to teach diverse meanings of sustainability and to engage the…

  15. An Experience of Science Theatre to Introduce Earth Interior and Natural Hazards to Children

    ERIC Educational Resources Information Center

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

    2015-01-01

    The present paper describes an experience of science theatre addressed to children of primary and secondary school, with the main purpose of making them acquainted with a topic, the interior of the Earth, largely underestimated in compulsory school curricula worldwide. A not less important task was to encourage a positive attitude towards natural…

  16. Experiments with a small behaviour controlled planetary rover

    NASA Technical Reports Server (NTRS)

    Miller, David P.; Desai, Rajiv S.; Gat, Erann; Ivlev, Robert; Loch, John

    1993-01-01

    A series of experiments that were performed on the Rocky 3 robot is described. Rocky 3 is a small autonomous rover capable of navigating through rough outdoor terrain to a predesignated area, searching that area for soft soil, acquiring a soil sample, and depositing the sample in a container at its home base. The robot is programmed according to a reactive behavior control paradigm using the ALFA programming language. This style of programming produces robust autonomous performance while requiring significantly less computational resources than more traditional mobile robot control systems. The code for Rocky 3 runs on an eight bit processor and uses about ten k of memory.

  17. Insights into the dynamics of planetary interiors obtained through the study of global distribution of volcanoes II: Tectonic implications from Venus

    NASA Astrophysics Data System (ADS)

    Cañon-Tapia, Edgardo

    2014-06-01

    The distribution of volcanic features is ultimately controlled by processes taking place beneath the surface of a planet. For this reason, characterization of volcano distribution at a global scale can be used to obtain insights concerning dynamic aspects of planetary interiors. Until present, studies of this type commonly have focused on volcanic features of a specific type (e.g., large volcanoes in Venus or hot-spot volcanism on Earth), or have concentrated on relatively small regions (i.e., vent distribution within individual volcanic fields), but no comparison of extensive databases has been made by using the same tools in both planets. In this work, the description of the distribution of volcanic features observed over the entire surface of Venus is made using the same tool used for Earth, and is applied to an extensive database. The analysis is based on density contours obtained with the Fisher kernel. As a result, several groupings of volcanoes are identified refining the already documented concentration of volcanoes on the BAT zone. In particular some doughnut-like patterns are observed that might be related to the action of mantle plumes. The occurrence of such features on Earth, as well as the existence of a uniform distribution of background volcanism on both planets, suggests similarities on their geodynamic behavior that had not been identified previously.

  18. The solubility of carbon monoxide in silicate melts at high pressures and its effect on silicate phase relations. [in terrestrial and other planetary interiors

    NASA Technical Reports Server (NTRS)

    Eggler, D. H.; Mysen, B. O.; Hoering, T. C.; Holloway, J. R.

    1979-01-01

    Autoradiographic analysis and gas chromatography were used to measure the solubility in silicate melts of CO-CO2 vapors (30 to 40% CO by thermodynamic calculation) in equilibrium with graphite at temperatures up to 1700 deg C and pressures to 30 kbar. At near-liquidus temperatures CO-CO2 vapors were found to be slightly more soluble than CO2 alone. As a result of the apparently negative temperature dependence of CO solubility, the solubility of CO-CO2 at superliquidus temperatures is less than that of CO2. Melting points of two silicates were depressed more by CO than by CO2. Phase boundary orientations suggest that CO/CO + CO2 is greater in the liquid than in the vapor. The effect of the presence of CO on periodotite phase relations was investigated, and it was found that melts containing both CO and CO2 are nearly as polymerized as those containing only CO2. These results suggest that crystallization processes in planetary interiors can be expected to be about the same, whether the melts contain CO2 alone or CO2 and CO.

  19. Lunar and Planetary Science XXXV: Impacts: Observations and Experiments

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The title in this section include: 1) Impactites of the Haughton Impact Structure, Devon Island, Nunavut, Canada; 2) Geochemical Characteristics of Impactites from the Yaxcopoil-1 ICDP Drill Core, Chicxulub Impact Structure, Mexico; 3) Investigation of the Ries Impact Crater Based upon Old and New Geophysical Data and Numerical Modeling; 4) Potential of Radar Imaging and Sounding Methods in Mapping Heavily Eroded Impact Craters: Mapping Some Structural Elements of the Hico Crater, TX; 5) From Simple to Complex Craters: The Mechanics of Late-time Crater Adjustments; 6) Impact Structures: What Does Crater Diameter Mean? 7) Early-Time Temperature Evolution of the Impact Flash and Beyond; 8) Probing Impact-Generated Vapor Plumes; 9) Non-Ballistic Vapor-Driven Ejecta; 10) Depth and Diameter of Transient Craters; 11) A Plausibility of Z-Model; 12) Experiments with Explosives and Ordnance Disposal Devices for the Simulation of Specific Processes During Shallow-Marine Impacts; 13) Collisional Fragmentation of Rotating Bodies.

  20. Planetary Radio Interferometry and Doppler Experiment (PRIDE) for the JUICE mission

    NASA Astrophysics Data System (ADS)

    Gurvits, L. I.; Bocanegra Bahamon, T. M.; Cimò, G.; Duev, D. A.; Molera Calvés, G.; Pogrebenko, S. V.; de Pater, I.; Vermeersen, L. L. A.; Rosenblatt, P.; Oberst, J.; Charlot, P.; Frey, S.; Tudose, V.

    2013-09-01

    The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a multi-disciplinary enhancement of the scientific suite of the Jupiter Icy Moons Explorer (JUICE). PRIDE will exploit the technique of Very Long Baseline Interferometry (VLBI) observations of spacecraft and natural celestial radio sources by a network of Earth-based radio telescopes (Fig. 1, see [1,2]). The main "measured deliverables" of PRIDE are lateral coordinates of spacecraft in the celestial reference frame. In addition to the lateral coordinates, a by-product of PRIDE is the measurement of the line-ofsight velocity of spacecraft. It is worth to notice the synergistic nature of PRIDE measurements to other key experiments of the JUICE mission, in particular addressing the quest of Icy Moons interior and Jovian system ephemerides. In addition of providing consistency checks of a number of experiments, PRIDE is highly synergistic to a number of other JUICE experiments, in particular radio science and laser ranging ones. Tracking of the spacecraft in the gravity field of Jupiter and its satellites will allow us to not only provide valuable inputs into the determination of the spacecraft trajectory, but also to improve the ephemerides of Jupiter and the Galilean Satellites. VLBI tracking of the spacecraft, in combination with routine observations of background radio sources of the celestial reference frame, will also allow us to firmly tie the Jupiter system into the celestial reference frame. This would represent a major contribution to the Solar System celestial mechanics and the definition of the Solar System reference system. Furthermore, PRIDE will contribute to various aspects of Ganymede's, Callisto's and Europa's science. VLBI positioning and radio occultation data may represent an important and independent reference for the GALA laser altimeter data. The trajectory data during the multiple satellite flybys will help to further constrain the low order gravity field parameters. In

  1. Planetary Radio Interferometry and Doppler Experiment (PRIDE) for the JUICE mission

    NASA Astrophysics Data System (ADS)

    Gurvits, L. I.; Bocanegra Bahamon, T. M.; Cimò, G.; Duev, D. A.; Molera Calvés, G.; Pogrebenko, S. V.; de Pater, I.; Vermeersen, L. L. A.; Rosenblatt, P.; Oberst, J.; Charlot, P.; Frey, S.; Tudose, V.

    2013-09-01

    The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a multi-disciplinary enhancement of the scientific suite of the Jupiter Icy Moons Explorer (JUICE). PRIDE will exploit the technique of Very Long Baseline Interferometry (VLBI) observations of spacecraft and natural celestial radio sources by a network of Earth-based radio telescopes (Fig. 1, see [1,2]). The main "measured deliverables" of PRIDE are lateral coordinates of spacecraft in the celestial reference frame. In addition to the lateral coordinates, a by-product of PRIDE is the measurement of the line-ofsight velocity of spacecraft. It is worth to notice the synergistic nature of PRIDE measurements to other key experiments of the JUICE mission, in particular addressing the quest of Icy Moons interior and Jovian system ephemerides. In addition of providing consistency checks of a number of experiments, PRIDE is highly synergistic to a number of other JUICE experiments, in particular radio science and laser ranging ones. Tracking of the spacecraft in the gravity field of Jupiter and its satellites will allow us to not only provide valuable inputs into the determination of the spacecraft trajectory, but also to improve the ephemerides of Jupiter and the Galilean Satellites. VLBI tracking of the spacecraft, in combination with routine observations of background radio sources of the celestial reference frame, will also allow us to firmly tie the Jupiter system into the celestial reference frame. This would represent a major contribution to the Solar System celestial mechanics and the definition of the Solar System reference system. Furthermore, PRIDE will contribute to various aspects of Ganymede's, Callisto's and Europa's science. VLBI positioning and radio occultation data may represent an important and independent reference for the GALA laser altimeter data. The trajectory data during the multiple satellite flybys will help to further constrain the low order gravity field parameters. In

  2. Planetary science experiments flying as hosted payloads on commercial satellites

    NASA Astrophysics Data System (ADS)

    Young, Eliot F.; Olkin, Cathy B.; Kalmanson, Phillip M.; Mellon, Russell; Young, Malcolm

    2009-08-01

    There has been a recent surge in interest in hosted and rideshare payloads that would launch aboard commercial communications satellites. Much of this interest originates with the satellite customers themselves as a way to sell excess mass and power margins that exist at launch. In 2008, NASA selected GOLD (Global-scale Observations of the Limb and Disk) as a mission of opportunity to fly as its first hosted payload experiment on a geosynchronous commercial communications satellite, a STAR-2 bus satellite built by Orbital Sciences. CHIRP (Commercially Hosted Infrared Payload), a hosted payload to test infrared sensors for the Air Force, is also being developed for a STAR-2 bus communications satellite. The mass limitation on a STAR-2 bus hosted payload is roughly 50 - 60 kg and the volume is roughly constrained to a 25" x 30" x 28" box on the nadir deck. Telescope apertures are therefore limited is size to about 50 cm in diameter. The diffraction limit for visible (much less IR) imaging missions barely improves upon ground-based image performance, but UV missions can achieve better than 0.1" resolution. There is at least one family of optical designs that (a) provide the necessary focal length and (b) are light and compact enough to fit within the STAR-2 bus mass and volume constraints. These designs also afford opportunities to maintain 0.05" pointing accuracy through a combination of a fine steering mirror and an orthogonal transfer CCD.

  3. The Potassium-Argon Laser Experiment (KARLE): In Situ Geochronology for Planetary Robotic Missions

    NASA Technical Reports Server (NTRS)

    Cohen, B. A.; Devismes, D.; Miller, J. S.; Swindle, T. D.

    2014-01-01

    Isotopic dating is an essential tool to establish an absolute chronology for geological events, including crystallization history, magmatic evolution, and alteration events. The capability for in situ geochronology will open up the ability for geochronology to be accomplished as part of lander or rover complement, on multiple samples rather than just those returned. An in situ geochronology package can also complement sample return missions by identifying the most interesting rocks to cache or return to Earth. The K-Ar Laser Experiment (KArLE) brings together a novel combination of several flight-proven components to provide precise measurements of potassium (K) and argon (Ar) that will enable accurate isochron dating of planetary rocks. KArLE will ablate a rock sample, measure the K in the plasma state using laser-induced breakdown spectroscopy (LIBS), measure the liberated Ar using mass spectrometry (MS), and relate the two by measuring the volume of the ablated pit by optical imaging. Our work indicates that the KArLE instrument is capable of determining the age of planetary samples with sufficient accuracy to address a wide range of geochronology problems in planetary science. Additional benefits derive from the fact that each KArLE component achieves analyses useful for most planetary surface missions.

  4. Simulation experiments for gamma-ray mapping of planetary surfaces: Scattering of high-energy neutrons

    NASA Technical Reports Server (NTRS)

    Brueckner, J.; Englert, P.; Reedy, R. C.; Waenke, H.

    1986-01-01

    The concentration and distribution of certain elements in surface layers of planetary objects specify constraints on models of their origin and evolution. This information can be obtained by means of remote sensing gamma-ray spectroscopy, as planned for a number of future space missions, i.e., Mars, Moon, asteroids, and comets. To investigate the gamma-rays made by interactions of neutrons with matter, thin targets of different composition were placed between a neutron-source and a high-resolution germanium spectrometer. Gamma-rays in the range of 0.1 to 8 MeV were accumulated. In one set of experiments a 14-MeV neutron generator using the T(d,n) reaction as neutron-source was placed in a small room. Scattering in surrounding walls produced a spectrum of neutron energies from 14 MeV down to thermal. This complex neutron-source induced mainly neutron-capture lines and only a few scattering lines. As a result of the set-up, there was a considerable background of discrete lines from surrounding materials. A similar situation exists under planetary exploration conditions: gamma-rays are induced in the planetary surface as well as in the spacecraft. To investigate the contribution of neutrons with higher energies, an experiment for the measurement of prompt gamma radiation was set up at the end of a beam-line of an isochronous cyclotron.

  5. The Potassium-Argon Laser Experiment (KArLE): In Situ Geochronology for Planetary Robotic Missions

    NASA Technical Reports Server (NTRS)

    Cohen, Barbara

    2016-01-01

    The Potassium (K) - Argon (Ar) Laser Experiment (KArLE) will make in situ noble-gas geochronology measurements aboard planetary robotic landers and roverss. Laser-Induced Breakdown Spectroscopy (LIBS) is used to measure the K abun-dance in a sample and to release its noble gases; the evolved Ar is measured by mass spectrometry (MS); and rela-tive K content is related to absolute Ar abundance by sample mass, determined by optical measurement of the ablated volume. KArLE measures a whole-rock K-Ar age to 10% or better for rocks 2 Ga or older, sufficient to resolve the absolute age of many planetary samples. The LIBS-MS approach is attractive because the analytical components have been flight proven, do not require further technical development, and provide complementary measurements as well as in situ geochronology.

  6. Planetary Rover Robotics Experiments in Education: HUSAR-5, the NXT-Based Rover Model for Measuring the Planetary Surface

    NASA Astrophysics Data System (ADS)

    Lang, Á.; Bérczi, Sz.; Szalay, K.; Prajczer, P.; Kocsis, Á.

    2014-11-01

    We report about the work of the HUSAR-5 groups from the Széchenyi István Gimnázium High School Sopron, Hungary. We build and program robot-rovers, that can autonomous move and measure on a planetary surface.

  7. Interior Vector Magnetic Field Monitoring for the SNS Neutron EDM Experiment

    NASA Astrophysics Data System (ADS)

    Nouri, Nima; Plaster, Brad

    2014-09-01

    A concept has been developed which provides for a real-time determination of the spatial dependence of the vector components of the magnetic field (and, hence, the ∂Bi / ∂xj field gradients) within the interior fiducial volume of the SNS neutron EDM experiment solely from exterior measurements at fixed discrete locations. This technique will be especially important during the operation of the experiment, when direct measurements of the field gradients present within the fiducial volume will not be physically possible. Our method, which is based on the solution to the Laplace Equation, is completely general and does not require the field to possess any type of symmetry. We describe the concept and our systematic approach for optimizing the locations of these exterior measurements. We also present results from prototyping studies of a field monitoring system deployed within a half-scale prototype of the experiment's magnetic field environment. A concept has been developed which provides for a real-time determination of the spatial dependence of the vector components of the magnetic field (and, hence, the ∂Bi / ∂xj field gradients) within the interior fiducial volume of the SNS neutron EDM experiment solely from exterior measurements at fixed discrete locations. This technique will be especially important during the operation of the experiment, when direct measurements of the field gradients present within the fiducial volume will not be physically possible. Our method, which is based on the solution to the Laplace Equation, is completely general and does not require the field to possess any type of symmetry. We describe the concept and our systematic approach for optimizing the locations of these exterior measurements. We also present results from prototyping studies of a field monitoring system deployed within a half-scale prototype of the experiment's magnetic field environment. This work was supported in part by the U.S. Department of Energy Office of

  8. Phenomenology of Neptune's radio emissions observed by the Voyager planetary radio astronomy experiment

    NASA Technical Reports Server (NTRS)

    Pedersen, B. M.; Lecacheux, A.; Zarka, P.; Aubier, M. G.; Kaiser, M. L.; Desch, M. D.

    1992-01-01

    The Neptune flyby in 1989 added a new planet to the known number of magnetized planets generating nonthermal radio emissions. We review the Neptunian radio emission morphology as observed by the planetary radio astronomy experiment on board Voyager 2 during a few weeks before and after closest approach. We present the characteristics of the two observed recurrent main components of the Neptunian kilometric radiation, i.e., the 'smooth' and the 'bursty' emissions, and we describe the many specific features of the radio spectrum during closest approach.

  9. Interior Vector Magnetic Field Monitoring via External Measurements for the SNS Neutron EDM Experiment

    NASA Astrophysics Data System (ADS)

    Nouri, Nima; Brown, Michael; Carr, Robert; Filippone, Bradley; Osthelder, Charles; Plaster, Bradley; Slutsky, Simon; Swank, Christopher

    2015-10-01

    A prototype of a magnetic field monitoring system designed to reconstruct the vector magnetic field components (and, hence, all nine of the ∂Bi / ∂xj field gradients) within the interior measurement fiducial volume solely from external measurements is under development for the SNS neutron EDM experiment. A first-generation room-temperature prototype array has already been tested. A second-generation prototype array consisting of 12 cryogenic-compatible fluxgate magnetometer probes will be deployed within the cold region of the experiment's 1 / 3 -scale cryogenic magnet testing apparatus. We will report progress towards the development of this second-generation prototype. This work was supported in part by the U. S. Department of Energy Office of Nuclear Physics under Award No. DE-FG02-08ER41557.

  10. Studying Venus' atmosphere and ionosphere with Planetary Radio Interferometry and Doppler Experiment (PRIDE)

    NASA Astrophysics Data System (ADS)

    Bocanegra-Bahamon, T. M.; Cimo, G.; Duev, D. A.; Gurvits, L. I.; Marty, J. Ch.; Pogrebenko, S. V.; Rosenblatt, P.

    2014-04-01

    The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a technique that can provide a multi-disciplinary enhancement of the science return of planetary missions. By performing precise Doppler tracking of a spacecraft carrier radio signal, at Earth-based radio telescopes, and VLBI-style processing of these signals in phase-referencing mode, the technique allows the determination of the radial velocity and lateral coordinates of the spacecraft with very high accuracy[1]. Because of the accurate examination of the changes in phase and amplitude of the radio signal propagating from the spacecraft to the multiple stations on Earth, the PRIDE technique can be used for several fields of planetary research. The application of this technique for atmospheric studies has been assessed by observing ESA's Venus Express (VEX) during Venus occultation events in 2012 and 2014, and by participating in one of the Venus Express Atmospheric Drag Experiment (VExADE) campaigns in 2012. Both studies are contributing to the characterization efforts of the atmosphere and ionosphere of Venus. During the Venus Express Atmospheric Drag Experiment (VExADE) campaigns VEX's orbit pericenter was lowered into an altitude range of approximately 165 to 175 km in order to probe Venus upper atmosphere above its north pole. The first VExADE campaigns were carried out between 2009-2010 using Doppler tracking data acquired by the VEX radio science experiment (VeRa), which provided the first in situ measurements of the density of Venus' polar thermosphere at solar minimum conditions [2]. In the December 2012 campaign the PRIDE-team participated by tracking VEX with several radio telescopes from the European VLBI Network (EVN) during pericenter passage. A Doppler frequency drop of ∼40 mHz was detected as VEX reached the lowest altitudes at around 170 km. The tracking data for each pericenter pass is fitted for precise orbit determination, from which drag acceleration estimates and the

  11. Social Media and Student Engagement in a Microgravity Planetary Science Experiment

    NASA Astrophysics Data System (ADS)

    Lane, S. S.; Lai, K.; Hoover, B.; Whitaker, A.; Tiller, C.; Benjamin, S.; Dove, A.; Colwell, J. E.

    2014-12-01

    The Collisional Accretion Experiment (CATE) is a planetary science experiment funded by NASA's Undergraduate Instrumentation Program (USIP). CATE is a microgravity experiment to study low-velocity collisions between cm-sized particles and 0.1-1.0 mm-sized particles in vacuum to better understand the conditions for accretion in the protoplanetary disk as well as collisions in planetary ring systems. CATE flew on three parabolic airplane flights in July, 2014, using NASA's "Weightless Wonder VI" aircraft. A significant part of the project was documenting the experience of designing, building, testing, and flying spaceflight hardware from the perspective of the undergraduates working on the experiment. The outreach effort was aimed at providing high schools students interested in STEM careers with a first-person view of hands-on student research at the university level. We also targeted undergraduates at the University of Central Florida to make them aware of space research on campus. The CATE team pursued multiple outlets, from social media to presentations at local schools, to connect with the public and with younger students. We created a website which hosted a blog, links to media publications that ran our story, videos, and galleries of images from work in the lab throughout the year. In addition the project had Facebook, Twitter, and Instagram accounts. These social media outlets had much more traffic than the website except during the flight week when photos posted on the blog generated significant traffic. The most effective means of communicating the project to the target audience, however, was through face-to-face presentations in classrooms. We saw a large increase in followers on Twitter and Instagram as the flight campaign got closer and while we were there. The main source of followers came after we presented to local high school students. These presentations were made by the undergraduate student team and the faculty mentors (Colwell and Dove).

  12. Intuition and Experience: Asteroid Surfaces, Meteorites and Planetary Geosciences in microgravity

    NASA Astrophysics Data System (ADS)

    Sears, D. W. G.; Moore, S. R.; Nichols, S.; Kareev, M.; Benoit, P. H.

    2002-09-01

    Planetary scientists considering geological processes that occur in microgravity, such as on the surface of asteroids, face an intrinsic difficulty in that humans have experienced a lifetime of observing Nature under the fairly substantial gravity field of the Earth. In order to accumulate some experience of how geological materials behave under microgravity, we have conducted three sets of experiments on the NASA KC-135 microgravity facility (the "vomit comet"). We examined the behavior of a variety of possible regolith simulants being disturbed under microgravity conditions: sand, iron filings, gravel, and even concrete. Each set of experiments was for a different purpose and the experimental details differed considerably, but some common results were: Particle size sorting of the surface material occurred readily Segregations that occurred early in the process are retained during considerable amounts of subsequent activity There are several implications of these results for planetary science. For instance, since the surface will be so easily disturbed and mineral and phase separations will occur so readily, it can be predicted that the surface of asteroids will reflect these processes and not the internal composition of the asteroid. Thus deductions made by spectroscopic observations of the surface will not simply yield meaningful information about their bulk composition. Similarly, chondrule and metal size sorting appears to be a common feature of meteorites could have occurred on the surfaces of their parent bodies, presumably asteroids, and not necessarily in the protosolar nebular. Furthermore, the nature of the segregations is not always intuitively obvious. In our sand and metal mixtures, iron frequently rose to the surface. Thus care should be taken in applying terrestrial experiences to microgravity situations like the surface of asteroids.

  13. Planetary Radio Interferometry and Doppler Experiment (PRIDE) for studying the thermosphere of Venus

    NASA Astrophysics Data System (ADS)

    Bocanegra Bahamón, T. M.; Cimò, G.; Duev, D. A.; Gurvits, L. I.; Marty, J. C.; Molera Calvés, G.; Pogrebenko, S. V.; Rosenblatt, P.

    2013-09-01

    Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a generic experimental setup of on-board and Earth-based radio devices and facilities, which serves as an enhancement of the science return of planetary missions. The main goal of this technique is to provide precise estimates of the spacecraft state vectors, by performing precise Doppler tracking of the spacecraft carrier signal, at one or more Earth-based radio telescopes, and VLBI-style correlation of these signals in phase referencing mode [1]. By allowing an accurate examination of the changes in phase and amplitude of the radio signal propagating from the spacecraft to the multiple stations on Earth, the PRIDE technique can be used for several fields of research, among them: atmospheric and ionospheric structure of planets and their satellites, planetary gravity fields, planets' shapes, masses and ephemerides, solar plasma and different aspects of the theory of general relativity. The PRIDE-team is participating in the so-called Venus Express Atmospheric Drag Experiment (VEx-ADE) campaigns by tracking ESA's Venus Express with multiple radio telescopes on Earth. During each campaign, VEX's orbit pericenter is lowered into an altitude range of approximately 165 to 175 km in order to probe Venus upper atmosphere above its north pole. The first VExADE campaigns were carried out between 2009-2010 using Doppler tracking data acquired by the VEX radio science experiment (VeRa), which provided the first in situ measurements of the density of Venus' polar thermosphere at solar minimum conditions [2]. The last campaign was conducted in December 2012, in which the PRIDE-team participated by tracking VEX with several radio telescopes from the European VLBI Network (EVN) during pericenter passage. A Doppler frequency drop of ∼40 mHz was detected as VEX reached the lowest altitudes at around 170 km. The tracking data for each pericenter pass is fitted for precise orbit determination, from which drag

  14. Planetary/DOD entry technology flight experiments. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Christensen, H. E.; Krieger, R. J.; Mcneilly, W. R.; Vetter, H. C.

    1976-01-01

    The feasibility of using the space shuttle to launch planetary and DoD entry flight experiments was examined. The results of the program are presented in two parts: (1) simulating outer planet environments during an earth entry test, the prediction of Jovian and earth radiative heating dominated environments, mission strategy, booster performance and entry vehicle design, and (2) the DoD entry test needs for the 1980's, the use of the space shuttle to meet these DoD test needs, modifications of test procedures as pertaining to the space shuttle, modifications to the space shuttle to accommodate DoD test missions and the unique capabilities of the space shuttle. The major findings of this program are summarized.

  15. Principal component analysis of Birkeland currents determined by the Active Magnetosphere and Planetary Electrodynamics Response Experiment

    NASA Astrophysics Data System (ADS)

    Milan, S. E.; Carter, J. A.; Korth, H.; Anderson, B. J.

    2015-12-01

    Principal component analysis is performed on Birkeland or field-aligned current (FAC) measurements from the Active Magnetosphere and Planetary Electrodynamics Response Experiment. Principal component analysis (PCA) identifies the patterns in the FACs that respond coherently to different aspects of geomagnetic activity. The regions 1 and 2 current system is shown to be the most reproducible feature of the currents, followed by cusp currents associated with magnetic tension forces on newly reconnected field lines. The cusp currents are strongly modulated by season, indicating that their strength is regulated by the ionospheric conductance at the foot of the field lines. PCA does not identify a pattern that is clearly characteristic of a substorm current wedge. Rather, a superposed epoch analysis of the currents associated with substorms demonstrates that there is not a single mode of response, but a complicated and subtle mixture of different patterns.

  16. Planetary rover robotics experiment in education: carbonate rock collecting experiment of the Husar-5 rover

    NASA Astrophysics Data System (ADS)

    Szalay, Kristóf; Lang, Ágota; Horváth, Tamás; Prajczer, Péter; Bérczi, Szaniszló

    2013-04-01

    Introduction: The new experiment for the Husar-5 educational space probe rover consists of steps of the technology of procedure of finding carbonate speci-mens among the rocks on the field. 3 main steps were robotized: 1) identification of carbonate by acid test, 2) measuring the gases liberated by acid, and 3) magnetic test. Construction of the experiment: The basis of the robotic realization of the experiment is a romote-controlled rover which can move on the field. Onto this rover the mechanism of the experiments were built from Technics LEGO elements and we used LEGO-motors for making move these experiments. The operation was coordinated by an NXT-brick which was suitable to programming. Fort he acetic-test the drops should be passed to the selected area. Passing a drop to a locality: From the small holder of the acid using densified gas we pump some drop onto the selected rock. We promote this process by pumpig the atmospheric gas into another small gas-container, so we have another higher pressure gas there. This is pumped into the acid-holder. The effect of the reaction is observed by a wireless onboard camera In the next step we can identify the the liberated gas by the gas sensor. Using it we can confirm the liberation of the CO2 gas without outer observer. The third step is the controll of the paramagnetic properties.. In measuring this feature a LEGO-compass is our instrumentation. We use a electric current gener-ated magnet. During the measurements both the coil and the gas-sensor should be positioned to be near to the surface. This means, that a lowering and an uplifting machinery should be constructed. Summary: The sequence of the measurement is the following. 1) the camera - after giving panorama images - turns toward the soil surface, 2) the dropping onto the rock surface 3) at the same time the gas-sensor starts to move down above the rock 4) the compass sensor also moves down on the arm which holds both the gas-sensor and the compass-sensor 5

  17. Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique: A test case of the Mars Express Phobos fly-by

    NASA Astrophysics Data System (ADS)

    Duev, D. A.; Pogrebenko, S. V.; Cimò, G.; Molera Calvés, G.; Bocanegra Bahamón, T. M.; Gurvits, L. I.; Kettenis, M. M.; Kania, J.; Tudose, V.; Rosenblatt, P.; Marty, J.-C.; Lainey, V.; de Vicente, P.; Quick, J.; Nickola, M.; Neidhardt, A.; Kronschnabl, G.; Ploetz, C.; Haas, R.; Lindqvist, M.; Orlati, A.; Ipatov, A. V.; Kharinov, M. A.; Mikhailov, A. G.; Lovell, J. E. J.; McCallum, J. N.; Stevens, J.; Gulyaev, S. A.; Natush, T.; Weston, S.; Wang, W. H.; Xia, B.; Yang, W. J.; Hao, L.-F.; Kallunki, J.; Witasse, O.

    2016-09-01

    Context. The closest ever fly-by of the Martian moon Phobos, performed by the European Space Agency's Mars Express spacecraft, gives a unique opportunity to sharpen and test the Planetary Radio Interferometry and Doppler Experiments (PRIDE) technique in the interest of studying planet-satellite systems. Aims: The aim of this work is to demonstrate a technique of providing high precision positional and Doppler measurements of planetary spacecraft using the Mars Express spacecraft. The technique will be used in the framework of Planetary Radio Interferometry and Doppler Experiments in various planetary missions, in particular in fly-by mode. Methods: We advanced a novel approach to spacecraft data processing using the techniques of Doppler and phase-referenced very long baseline interferometry spacecraft tracking. Results: We achieved, on average, mHz precision (30 μm/s at a 10 s integration time) for radial three-way Doppler estimates and sub-nanoradian precision for lateral position measurements, which in a linear measure (at a distance of 1.4 AU) corresponds to ~50 m.

  18. Detection of dust impacts by the Voyager planetary radio astronomy experiment

    NASA Technical Reports Server (NTRS)

    Evans, David R.

    1993-01-01

    The Planetary Radio Astronomy (PRA) instrument detected large numbers of dust particles during the Voyager 2 encounter with Neptune. The signatures of these impacts are analyzed in some detail. The major conclusions are described. PRA detects impacts from all over the spacecraft body, not just the PRA antennas. The signatures of individual impacts last substantially longer than was expected from complementary Plasma Wave Subsystem (PWS) data acquired by another Voyager experiment. The signatures of individual impacts demonstrate very rapid fluctuations in signal strength, so fast that the data are limited by the speed of response of the instrument. The PRA detects events at a rate consistently lower than does the Plasma Wave subsystem. Even so, the impact rate is so great near the inbound crossing of the ring plane that no reliable estimate of impact rate can be made for this period. The data are consistent with the presence of electrons accelerated by ions within an expanding plasma cloud from the point of impact. An ancillary conclusion is that the anomalous appearance of data acquired at 900 kHz appears to be due to an error in processing the PRA data prior to their delivery rather than due to overload of the PRA instrument.

  19. High Pressure Cosmochemistry of Major Planetary Interiors: Laboratory Studies of the Water-rich Region of the System Ammonia-water

    NASA Technical Reports Server (NTRS)

    Nicol, M.; Johnson, M.; Koumvakalis, A. S.

    1985-01-01

    The behavior of gas-ice mixtures in major planets at very high pressures was studied. Some relevant pressure-temperature-composition (P-T-X) regions of the hydrogen (H2)-helium (He)-water (H2O-ammonia (NH3)-methane (CH4) phase diagram were determined. The studies, and theoretical model, of the relevant phases, are needed to interpret the compositions of ice-gas systems at conditions of planetary interest. The compositions and structures of a multiphase, multicomponent system at very high pressures care characterized, and the goal is to characterize this system over a wide range of low and high temperatures. The NH3-H2O compositions that are relevant to planetary problems yet are easy to prepare were applied. The P-T surface of water was examined and the corresponding surface for NH3 was determined. The T-X diagram of ammonia-water at atmospheric pressure was studied and two water-rich phases were found, NH3-2H2O (ammonia dihydrate), which melts incongruently, and NH3.H2O (ammonia monohydrate), which is nonstoichiometric and melts at a higher temperature than the dihydrate. It is suggested that a P-T surface at approximately the monohydrate composition and the P-X surface at room temperature is determined.

  20. Continued Development of in Situ Geochronology for Planetary Using KArLE (Potassium-Argon Laser Experiment)

    NASA Technical Reports Server (NTRS)

    Devismes, D.; Cohen, B. A.

    2016-01-01

    Geochronology is a fundamental measurement for planetary samples, providing the ability to establish an absolute chronology for geological events, including crystallization history, magmatic evolution, and alteration events, and providing global and solar system context for such events. The capability for in situ geochronology will open up the ability for geochronology to be accomplished as part of lander or rover complement, on multiple samples rather than just those returned. An in situ geochronology package can also complement sample return missions by identifying the most interesting rocks to cache or return to Earth. The K-Ar radiometric dating approach to in situ dating has been validated by the Curiosity rover on Mars as well as several laboratories on Earth. Several independent projects developing in situ rock dating for planetary samples, based on the K-Ar method, are giving promising results. Among them, the Potassium (K)-Argon Laser Experiment (KArLE) at MSFC is based on techniques already in use for in planetary exploration, specifically, Laser-induced Breakdown Spectroscopy (LIBS, used on the Curiosity Chemcam), mass spectroscopy (used on multiple planetary missions, including Curiosity, ExoMars, and Rosetta), and optical imaging (used on most missions).

  1. Initial Results from the Experimental Measurement Campaign (XMC) for Planetary Boundary Layer (PBL) Instrument Assessment (XPIA) Experiment

    NASA Astrophysics Data System (ADS)

    Brewer, W. A.; Choukulkar, A.; Sandberg, S.; Weickmann, A.; Lundquist, J.; Iungo, V.; Newsom, R.; Delgado, R.

    2016-06-01

    The Experimental Measurement Campaign (XMC) for Planetary Boundary Layer (PBL) Instrument Assessment (XPIA) is a DOE funded study to develop and validate methods of making three dimensional measurements of wind fields. These techniques are of interest to study wind farm inflows and wake flows using remote sensing instrumentation. The portion of the experiment described in this presentation utilizes observations from multiple Doppler wind lidars, soundings, and an instrumented 300m tower, the Boulder Atmospheric Observatory (BAO) in Erie, Colorado.

  2. Planetary Science Resource Data Model

    NASA Astrophysics Data System (ADS)

    Cecconi, B.; Berthier, J.; Bourrel, N.; Gangloff, M.; Erard, S.; Le Sidaner, P.; André, N.; Jacquey, C.; Lormant, N.

    2012-09-01

    One the goals of the Europlanet/IDIS project is the prototyping a Planetary Sciences Virtual Observatory (VO). Planetary sciences are covering several science thematics: atmospheres, surfaces, interiors, small bodies, orbital parameters, in situ exploration, plasma (waves, particle and fields), radio astronomy... They also include a large variety of data types: images, spectra, times series, movies, dynamic spectra, profiles, maps... and an even larger variety of physical parameters, including remote data, in-situ data, models, lab experiments, field analogs. The main challenge is thus to be able to homogeneously describe all the planetary science resources (dataset, files, services...). The skeleton of a such a description is the data model. The Planetary Science Resource Data Model (PSRDM) has been built using IVOA (International Virtual Observatory Alliance). We describe the content of Datasets and Granules (i.e., product, file, or the smallest granularity distributed by the service), not the access to the data. This description includes: Resource identification, Targets, Instruments (including hosting facility), Axis (including bounds, resolution, sampling, unit), Physical parameter (including UCD, unit).

  3. Planetary Seismology

    NASA Technical Reports Server (NTRS)

    Weber, Renee C.

    2015-01-01

    Of the many geophysical means that can be used to probe a planet's interior, seismology remains the most direct. In addition to Earth, seismometers have been installed on Venus, Mars, and the Moon. Given that the seismic data gathered on the Moon (now over 40 years ago) revolutionized our understanding of the Moon and are still being used today to produce new insight into the state of the lunar interior, it is no wonder that many future missions, both real and conceptual, plan to take seismometers to other planets. To best facilitate the return of high-quality data from these instruments, as well as to further our understanding of the dynamic processes that modify a planet's interior, various modeling approaches are used to quantify parameters such as the amount and distribution of seismicity, tidal deformation, and seismic structure of the terrestrial planets. In addition, recent advances in wavefield modeling have permitted a renewed look at seismic energy transmission and the effects of attenuation and scattering, as well as the presence and effect of a core, on recorded seismograms. In this talk I will discuss some of these methods and review the history of planetary seismology.

  4. Using Space Weather Forecast Tools for Understanding Planetary Magnetospheres: MESSENGER Experience Applied to MAVEN Studies

    NASA Astrophysics Data System (ADS)

    Baker, Daniel N.; Dewey, R. M.; Brain, D. A.; Jakosky, Bruce; Halekas, Jasper; Connerney, Jack; Odstrcil, Dusan; Mays, M. Leila; Luhmann, Janet

    2015-04-01

    The Wang-Sheeley-Arge (WSA)-ENLIL solar wind modeling tool has been used to calculate the values of interplanetary magnetic field (IMF) strength (B), solar wind speed (V), density (n), ram pressure (~nV2), cross-magnetosphere electric field (VxB), Alfvén Mach number (MA), and other derived quantities of relevance for space weather purposes at Earth. Such parameters as solar wind dynamic pressure can be key for estimating the magnetopause standoff distance, as just one example. The interplanetary electric field drives many magnetospheric dynamical processes and can be compared with general magnetic activity indices and with the occurrence of energetic particle bursts within the Earth’s magnetosphere. Such parameters also serve as input to the global magnetohydrodynamic and kinetic magnetosphere models that are used to forecast magnetospheric and ionospheric processes. Such modeling done for Earth space weather forecasting has helped assess near-real-time magnetospheric behavior for MESSENGER at Mercury (as well as other mission analysis and Mercury ground-based observational campaigns). This solar-wind forcing knowledge has provided a crucial continuing step toward bringing heliospheric science expertise to bear on solar-planetary interaction studies. The experience gained from MESSENGER at Mercury is now being applied to the new observations from the MAVEN (Mars Atmosphere and Volatile Evolution) mission at Mars. We compare the continuous WSA-ENLIL results derived from modeling to the MAVEN SWIA and MAG data from mid-December 2014 to the present time. This provides a broader contextual view of solar wind forcing at Mars and also allows a broader validation of the ENLIL model results throughout the inner heliosphere.

  5. NanoRocks: A Long-Term Microgravity Experiment to Stydy Planet Formation and Planetary Ring Particles

    NASA Astrophysics Data System (ADS)

    Brisset, J.; Colwell, J. E.; Dove, A.; Maukonen, D.; Brown, N.; Lai, K.; Hoover, B.

    2015-12-01

    We report on the results of the NanoRocks experiment on the International Space Station (ISS), which simulates collisions that occur in protoplanetary disks and planetary ring systems. A critical stage of the process of early planet formation is the growth of solid bodies from mm-sized chondrules and aggregates to km-sized planetesimals. To characterize the collision behavior of dust in protoplanetary conditions, experimental data is required, working hand in hand with models and numerical simulations. In addition, the collisional evolution of planetary rings takes place in the same collisional regime. The objective of the NanoRocks experiment is to study low-energy collisions of mm-sized particles of different shapes and materials. An aluminum tray (~8x8x2cm) divided into eight sample cells holding different types of particles gets shaken every 60 s providing particles with initial velocities of a few cm/s. In September 2014, NanoRocks reached ISS and 220 video files, each covering one shaking cycle, have already been downloaded from Station. The data analysis is focused on the dynamical evolution of the multi-particle systems and on the formation of cluster. We track the particles down to mean relative velocities less than 1 mm/s where we observe cluster formation. The mean velocity evolution after each shaking event allows for a determination of the mean coefficient of restitution for each particle set. These values can be used as input into protoplanetary disk and planetary rings simulations. In addition, the cluster analysis allows for a determination of the mean final cluster size and the average particle velocity of clustering onset. The size and shape of these particle clumps is crucial to understand the first stages of planet formation inside protoplanetary disks as well as many a feature of Saturn's rings. We report on the results from the ensemble of these collision experiments and discuss applications to planetesimal formation and planetary ring

  6. Planetary science: A lunar perspective

    NASA Technical Reports Server (NTRS)

    Taylor, S. R.

    1982-01-01

    An interpretative synthesis of current knowledge on the moon and the terrestrial planets is presented, emphasizing the impact of recent lunar research (using Apollo data and samples) on theories of planetary morphology and evolution. Chapters are included on the exploration of the solar system; geology and stratigraphy; meteorite impacts, craters, and multiring basins; planetary surfaces; planetary crusts; basaltic volcanism; planetary interiors; the chemical composition of the planets; the origin and evolution of the moon and planets; and the significance of lunar and planetary exploration. Photographs, drawings, graphs, tables of quantitative data, and a glossary are provided.

  7. Computational experience with a dense column feature for interior-point methods

    SciTech Connect

    Wenzel, M.; Czyzyk, J.; Wright, S.

    1997-08-01

    Most software that implements interior-point methods for linear programming formulates the linear algebra at each iteration as a system of normal equations. This approach can be extremely inefficient when the constraint matrix has dense columns, because the density of the normal equations matrix is much greater than the constraint matrix and the system is expensive to solve. In this report the authors describe a more efficient approach for this case, that involves handling the dense columns by using a Schur-complement method and conjugate gradient interaction. The authors report numerical results with the code PCx, into which the technique now has been incorporated.

  8. Planetary magnetism

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    1981-01-01

    A synoptic view of early and recent data on the planetary magnetism of Mercury, Venus, the moon, Mars, Jupiter, and Saturn is presented. The data on Mercury from Mariner 10 are synthesized with various other sources, while data for Venus obtained from 120 orbits of Pioneer Venus give the upper limit of the magnetic dipole. Explorer 35 Lunar Orbiter data provided the first evidence of lunar magnetization, but it was the Apollo subsatellite data that measured accurately the magnetic dipole of the moon. A complete magnetic survey of Mars is still needed, and only some preliminary data are given on the magnetic dipole of the planet. Figures on the magnetic dipoles of Jupiter and Saturn are also suggested. It is concluded that if the magnetic field data are to be used to infer the interior properties of the planets, good measures of the multiple harmonics in the field are needed, which may be obtained only through low altitude polar orbits.

  9. Radar Sounding for Planetary Subsurface Exploration: Translating the Mars Experience to Jupiter's Icy Moons

    NASA Astrophysics Data System (ADS)

    Plaut, J.

    2015-12-01

    Exploration of the subsurface of Mars using radar sounding began with MARSIS (Mars Advanced Radar for Subsurface and Ionospheric Sounding) on Mars Express in 2005 and continued with SHARAD (Shallow Radar) on Mars Reconnaissance Orbiter in 2006. These instruments have been operating continuously since, providing a rich legacy of science return and observational experience in the highly variable environments and target sets at Mars. New missions to the icy moons of Jupiter, ESA's JUICE (Jupiter Icy Moon Explorer) and NASA's Europa Mission, will both carry radar sounders to probe the subsurface of several of the icy moons (Ganymede, Europa and Callisto by JUICE; Europa by the Europa Mission). The success of the Mars sounders demonstrated the scientific value of the technique and provided confidence that sounding of the icy moons is a promising endeavor. Icy targets at Mars have proven especially amenable to penetration by radar sounding. The polar layered deposits of Mars have been probed to their base (2-4 km deep) by MARSIS, operating at frequencies of 1.3-5.5 MHz. SHARAD, operating with a wider bandwidth at 15-25 MHz, provides higher vertical resolution that allows detection and imaging of fine details of interior layering in the ice deposits. The sounder planned for the Europa mission, REASON (Radar for Europa Assessment and Sounding, Ocean to Near-Surface), will utilize simultaneous dual frequency signals to obtain complementary deep sounding and high-vertical-resolution shallow observations. Co-located observations by MARSIS and SHARAD also demonstrate that high surface roughness (relative to the radar wavelength) affects the strength of the penetrating signals, and thus the capability to detect deep or low-contrast subsurface interfaces. The icy moon sounders' wavelengths were selected, in part, to mitigate against this degradation of signals by the anticipated rough surfaces of Jupiter's moons. This paper will discusss these and other examples of lessons

  10. Resistance of Bacterial Endospores to Outer Space for Planetary Protection Purposes—Experiment PROTECT of the EXPOSE-E Mission

    PubMed Central

    Moeller, Ralf; Cadet, Jean; Douki, Thierry; Mancinelli, Rocco L.; Nicholson, Wayne L.; Panitz, Corinna; Rabbow, Elke; Rettberg, Petra; Spry, Andrew; Stackebrandt, Erko; Vaishampayan, Parag; Venkateswaran, Kasthuri J.

    2012-01-01

    Abstract Spore-forming bacteria are of particular concern in the context of planetary protection because their tough endospores may withstand certain sterilization procedures as well as the harsh environments of outer space or planetary surfaces. To test their hardiness on a hypothetical mission to Mars, spores of Bacillus subtilis 168 and Bacillus pumilus SAFR-032 were exposed for 1.5 years to selected parameters of space in the experiment PROTECT during the EXPOSE-E mission on board the International Space Station. Mounted as dry layers on spacecraft-qualified aluminum coupons, the “trip to Mars” spores experienced space vacuum, cosmic and extraterrestrial solar radiation, and temperature fluctuations, whereas the “stay on Mars” spores were subjected to a simulated martian environment that included atmospheric pressure and composition, and UV and cosmic radiation. The survival of spores from both assays was determined after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110 nm) as well as the martian UV spectrum (λ≥200 nm) was the most deleterious factor applied; in some samples only a few survivors were recovered from spores exposed in monolayers. Spores in multilayers survived better by several orders of magnitude. All other environmental parameters encountered by the “trip to Mars” or “stay on Mars” spores did little harm to the spores, which showed about 50% survival or more. The data demonstrate the high chance of survival of spores on a Mars mission, if protected against solar irradiation. These results will have implications for planetary protection considerations. Key Words: Planetary protection—Bacterial spores—Space experiment—Simulated Mars mission. Astrobiology 12, 445–456. PMID:22680691

  11. Resistance of bacterial endospores to outer space for planetary protection purposes--experiment PROTECT of the EXPOSE-E mission.

    PubMed

    Horneck, Gerda; Moeller, Ralf; Cadet, Jean; Douki, Thierry; Mancinelli, Rocco L; Nicholson, Wayne L; Panitz, Corinna; Rabbow, Elke; Rettberg, Petra; Spry, Andrew; Stackebrandt, Erko; Vaishampayan, Parag; Venkateswaran, Kasthuri J

    2012-05-01

    Spore-forming bacteria are of particular concern in the context of planetary protection because their tough endospores may withstand certain sterilization procedures as well as the harsh environments of outer space or planetary surfaces. To test their hardiness on a hypothetical mission to Mars, spores of Bacillus subtilis 168 and Bacillus pumilus SAFR-032 were exposed for 1.5 years to selected parameters of space in the experiment PROTECT during the EXPOSE-E mission on board the International Space Station. Mounted as dry layers on spacecraft-qualified aluminum coupons, the "trip to Mars" spores experienced space vacuum, cosmic and extraterrestrial solar radiation, and temperature fluctuations, whereas the "stay on Mars" spores were subjected to a simulated martian environment that included atmospheric pressure and composition, and UV and cosmic radiation. The survival of spores from both assays was determined after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110 nm) as well as the martian UV spectrum (λ≥200 nm) was the most deleterious factor applied; in some samples only a few survivors were recovered from spores exposed in monolayers. Spores in multilayers survived better by several orders of magnitude. All other environmental parameters encountered by the "trip to Mars" or "stay on Mars" spores did little harm to the spores, which showed about 50% survival or more. The data demonstrate the high chance of survival of spores on a Mars mission, if protected against solar irradiation. These results will have implications for planetary protection considerations. PMID:22680691

  12. On the generation of sound by turbulent convection. I - A numerical experiment. [in solar interior

    NASA Technical Reports Server (NTRS)

    Bogdan, Thomas J.; Cattaneo, Fausto; Malagoli, Andrea

    1993-01-01

    Motivated by the problem of the origin of the solar p-modes, we study the generation of acoustic waves by turbulent convection. Our approach uses the results of high-resolution 3D simulations as the experimental basis for our investigation. The numerical experiment describes the evolution of a horizontally periodic layer of vigorously convecting fluid. The sound is measured by a procedure, based on a suitable linearization of the equations of compressible convection that allows the amplitude of the acoustic field to be determined. Through this procedure we identify unambiguously some 400 acoustic modes. The total energy of the acoustic field is found to be a fraction of a percent of the kinetic energy of the convection. The amplitudes of the observed modes depend weakly on (horizontal) wavenumber but strongly on frequency. The line widths of the observed modes typically exceed the natural linewidths of the modes as inferred from linear theory. This broadening appears to be related to the (stochastic) interaction between the modes and the underlying turbulence which causes abrupt, episodic events during which the phase coherence of the modes is lost.

  13. Planetary rings

    SciTech Connect

    Greenberg, R.; Brahic, A.

    1984-01-01

    Among the topics discussed are the development history of planetary ring research, the view of planetary rings in astronomy and cosmology over the period 1600-1900, the characteristics of the ring systems of Saturn and Uranus, the ethereal rings of Jupiter and Saturn, dust-magnetosphere interactions, the effects of radiation forces on dust particles, the collisional interactions and physical nature of ring particles, transport effects due to particle erosion mechanisms, and collision-induced transport processes in planetary rings. Also discussed are planetary ring waves, ring particle dynamics in resonances, the dynamics of narrow rings, the origin and evolution of planetary rings, the solar nebula and planetary disk, future studies of the planetary rings by space probes, ground-based observatories and earth-orbiting satellites, and unsolved problems in planetary ring dynamics.

  14. STELLAR WIND INFLUENCE ON PLANETARY DYNAMOS

    SciTech Connect

    Heyner, Daniel; Glassmeier, Karl-Heinz; Schmitt, Dieter

    2012-05-10

    We examine the possible influence of early stellar wind conditions on the evolution of planetary dynamo action. In our model, the dynamo operates within a significant ambient magnetospheric magnetic field generated by the interaction between the stellar wind and the planetary magnetic field. This provides a negative feedback mechanism which quenches the dynamo growth. The external magnetic field magnitude which the dynamo experiences, and thus the strength of the quenching, depends on the stellar wind dynamic pressure. As this pressure significantly changes during stellar evolution, we argue that under early stellar system conditions the coupling between the stellar wind and the interior dynamics of a planet is much more important than has been thought up to now. We demonstrate the effects of the feedback coupling in the course of stellar evolution with a planet at a similar distance to the central star as Mercury is to the Sun.

  15. Planetary Geophysics and Tectonics

    NASA Technical Reports Server (NTRS)

    Parmentier, E. M.

    1997-01-01

    Research supported by grant NAGW-1928 has addressed a variety of problems related to planetary evolution. One important focus has been on questions related to the role of chemical buoyancy in planetary evolution with application to both Venus and the Moon. We have developed a model for the evolution of the Moon (Hess and Parmentier, 1995) in which dense, highly radioactive, late stage magma ocean cumulates sink forming a core. This core heats the overlying, chemically layered mantle giving rise to a heated, chemically well-mixed layer that thickens with time. This Mixed layer eventually becomes hot enough and thick enough that its top begins to melt at a pressure low enough that melt is buoyant, thus creating mare basalts from a high pressure source of the correct composition and at an appropriate time in lunar evolution. In work completed during the last year, numerical experiments on convection in a chemically stably stratified fluid layer heated from below have been completed. These results show us how to calculate the evolution of a mixed layer in the Moon, depending on the heat production in the ilmenite- cumulate core and the chemical stratification of the overlying mantle. Chemical stratification of the mantle after its initial differentiation is would trap heat in the deep interior and prevent the rapid rise of plumes with accompanying volcanism. This trapping of heat in the interior can explain the thickness of the lunar lithosphere as a function of time as well as the magmatic evolution. We show that heat transported to the base of the lithosphere at a rate determined by current estimates of radioactivity in the Moon would not satisfy constraints on elastic lithosphere thickness from tectonic feature associated with basin loading. Trapping heat at depth by a chemically stratified mantle may also explain the absence of global compressional features on the surface that previous models predict for an initially hot lunar interior. For Venus, we developed a

  16. Interior Design.

    ERIC Educational Resources Information Center

    Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

    This document contains teacher's materials for an eight-unit secondary education vocational home economics course on interior design. The units cover period styles of interiors, furniture and accessories, surface treatments and lighting, appliances and equipment, design and space planning in home and business settings, occupant needs, acquisition…

  17. Interiors and atmospheres of the outer planets

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.

    1991-01-01

    This theoretical/observational project constrains structure of outer planet atmospheres and interiors through observational data. The primary observation tool is through observations of occultations of stars by outer solar system objects, which yield information about atmospheric temperatures and dynamics, and planetary dimensions and oblateness. The theoretical work relates the data to interior structures in a variety of ways.

  18. Impact Cratering Experiment for a Course in Lunar and Planetary Geology.

    ERIC Educational Resources Information Center

    Smith, Eugene; And Others

    1980-01-01

    Described is an inexpensive and safe laboratory experiment that accurately duplicates the shapes and structures of simple impact craters using fireplace ash, finely ground charcoal, and an air gun. (Author/DS)

  19. Continued development of the Combined Pulsed Neutron Experiment (CPNE) for lunar and planetary surfaces

    NASA Technical Reports Server (NTRS)

    Mandler, J. W.

    1973-01-01

    Current progress is reported on the inelastic scattering, capture, and activation gamma ray portions of the Combined Pulsed Neutron Experiment (CPNE). Experiments are described which have enabled a reduction in weight of the experimental probe to 7.3 kg. Parametric studies are described which enabled the optimization of experimental parameters (e.g., gate time settings, neutron pulse rate, etc.). Estimated detection sensitivities using this light weight probe and the optimized experimental parameters are discussed.

  20. Planetary Data Definition

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Planetary data include all of those data which have resulted from measurements made by the instruments carried aboard planetary exploration spacecraft, and (for our purposes) exclude observations of Moon and Earth. The working, planetary data base is envisioned to contain not only these data, but also a wide range of supporting measurements such as calibration files, navigation parameters, spacecraft engineering states, and the various Earth-based and laboratory measurements which provide the planetary research scientist with historical and comparative data. No convention exists across the disciplines of the planetary community for defining or naming the various levels through which data pass in the progression from a sensed impulse at the spacecraft to a reduced, calibrated, and/or analyzed element in a planetary data set. Terms such as EDR (experiment data record), RDR (reduced data record), and SEDR (supplementary experiment data record) imply different meanings depending on the data set under consideration. The development of standard terminology for the general levels of planetary data is necessary.

  1. Planetary data definition

    NASA Astrophysics Data System (ADS)

    1984-10-01

    Planetary data include all of those data which have resulted from measurements made by the instruments carried aboard planetary exploration spacecraft, and (for our purposes) exclude observations of Moon and Earth. The working, planetary data base is envisioned to contain not only these data, but also a wide range of supporting measurements such as calibration files, navigation parameters, spacecraft engineering states, and the various Earth-based and laboratory measurements which provide the planetary research scientist with historical and comparative data. No convention exists across the disciplines of the planetary community for defining or naming the various levels through which data pass in the progression from a sensed impulse at the spacecraft to a reduced, calibrated, and/or analyzed element in a planetary data set. Terms such as EDR (experiment data record), RDR (reduced data record), and SEDR (supplementary experiment data record) imply different meanings depending on the data set under consideration. The development of standard terminology for the general levels of planetary data is necessary.

  2. Interior structure of Uranus

    SciTech Connect

    Hubbard, W.B.

    1984-10-01

    Key measurements are discussed which are diagnostic of Uranus interior structure and evolutionary history, and reviews their present status. Typical interior models have chondritic cores, but have the bulk of their mass in an envelope consisting of ice component, principally H2O. The total amount of free H2 in the planet cannot exceed approximately 1 to 2 earth masses. Measurements of the gravitational moments of Uranus are beginning to be accurate enough to constrain models, but are limited in utility by uncertainty in the rotation period. Discussed is evidence that the outermost planetary layers have a gravitationally significant quantity of denser material (ice component) in addition to H2 and He. The He/H ratio and the deuterium abundance in the atmosphere may be diagnostic of the planet's previous evolutionary history. It is argued that the planet's interior is likely to now be at a temperature approximately 10(3) deg K. Uranus interior with Neptune's in a number of ways, considering heat flow, degree of internal differentiation, and possible magnetic field.

  3. Interior Noise

    NASA Technical Reports Server (NTRS)

    Mixson, John S.; Wilby, John F.

    1991-01-01

    The generation and control of flight vehicle interior noise is discussed. Emphasis is placed on the mechanisms of transmission through airborne and structure-borne paths and the control of cabin noise by path modification. Techniques for identifying the relative contributions of the various source-path combinations are also discussed along with methods for the prediction of aircraft interior noise such as those based on the general modal theory and statistical energy analysis.

  4. Planetary Radar

    NASA Technical Reports Server (NTRS)

    Neish, Catherine D.; Carter, Lynn M.

    2015-01-01

    This chapter describes the principles of planetary radar, and the primary scientific discoveries that have been made using this technique. The chapter starts by describing the different types of radar systems and how they are used to acquire images and accurate topography of planetary surfaces and probe their subsurface structure. It then explains how these products can be used to understand the properties of the target being investigated. Several examples of discoveries made with planetary radar are then summarized, covering solar system objects from Mercury to Saturn. Finally, opportunities for future discoveries in planetary radar are outlined and discussed.

  5. Laboratory experiments on planetary and stellar convection performed on spacelab 3.

    PubMed

    Hart, J E; Toomre, J; Deane, A E; Hurlburt, N E; Glatzmaier, G A; Fichtl, G H; Leslie, F; Fowlis, W W; Gilman, P A

    1986-10-01

    Experiments on thermal convection in a rotating, differentially heated hemispherical shell with a radial buoyancy force were conducted in an orbiting microgravity laboratory. A variety of convective structures, or planforms, were observed, depending on the magnitude of the rotation and the nature of the imposed heating distribution. The results are compared with numerical simulations that can be conducted at the more modest heating rates, and suggest possible regimes of motion in rotating planets and stars. PMID:17742634

  6. Classroom virtual lab experiments as teaching tools for explaining how we understand planetary processes

    NASA Astrophysics Data System (ADS)

    Hill, C. N.; Schools, H.; Research Team Members

    2012-12-01

    This presentation will report on a classroom pilot study in which we teamed with school teachers in four middle school classes to develop and deploy course modules that connect the real-world to virtual forms of laboratory experiments.The broad goal is to help students realize that seemingly complex Earth system processes can be connected to basic properties of the planet and that this can be illustrated through idealized experiment. Specifically the presentation will describe virtual modules based on on-demand cloud computing technologies that allow students to test the notion that pole equator gradients in radiative forcing together with rotation can explain characteristic patterns of flow in the atmosphere. The module developed aligns with new Massachusetts science standard requirements regarding understanding of weather and climate processes. These new standards emphasize an appreciation of differential solar heating and a qualitative understanding of the significance of rotation. In our preliminary classroom pilot studies we employed pre and post evaluation tests to establish that the modules had increased student knowledge of phenomenology and terms. We will describe the results of these tests as well as results from anecdotal measures of student response. This pilot study suggests that one way to help make Earth science concepts more tractable to a wider audience is through virtual experiments that distill phenomena down, but still retain enough detail that students can see the connection to the real world. Modern computer technology and developments in research models appear to provide an opportunity for more work in this area. We will describe some follow-up possibilities that we envisage.

  7. The morphology of lava flows in planetary environments - Predictions from analog experiments

    NASA Technical Reports Server (NTRS)

    Griffiths, Ross W.; Fink, Jonathan H.

    1992-01-01

    Computations are carried out of the rates of surface cooling and lateral flow of lavas extruded onto the surfaces of terrestrial planets and the outer planet satellites, and the likely flow morphologies predicted by extrapolation of the laboratory analog results are determined. Results of this approach are presented for the earth, Venus, Mars, the moon, and the silicate flows on Io. The experiments, which involved the spreading of a viscous liquid under gravity in the presence of a solidifying surface crust, revealed a set of four distinct surface morphologies.

  8. Observing Dynamics in Large-Scale Birkeland Currents with the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE)

    NASA Astrophysics Data System (ADS)

    Anderson, B. J.; Korth, H.; Waters, C. L.; Barnes, R. J.; Olson, C.

    2015-12-01

    The Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) provides continuous global observations of the magnetic perturbations that predominantly reflect Birkeland currents. The data are acquired by avionics magnetometers of the Iridium satellites and allow measurements from 66 satellites in near-polar circular, low altitude orbits. The configuration of the Iridium satellite constellation determines the longitude sampling spacing of ~ 2 hours and the re-sampling cadence of the system which is 9 minutes. From 2008 to 2013 the AMPERE system was developed which included new flight software on the Iridium satellites to allow telemetry of higher rate data to the ground and the Science Data Center to derive Birkeland current perturbations from the data and invert these signals to derive the global distributions of the currents using data windows of ten minutes. There were many challenges in developing AMPERE including automating inter-calibration between satellites and the baseline determination and removals. The results of AMPERE provide stunning confirmation of many of the statistical estimates for the distribution of currents but more significantly open a new window to understand their instantaneous distribution and dynamics. Examples of new features of the currents and their dynamics revealed by AMPERE are presented. In addition, prospects for new data products and increased data quality anticipated from AMPERE-NEXT to be implemented on the Iridium-NEXT generation of satellites are discussed.

  9. A model for eastward and westward jets in laboratory experiments and planetary atmospheres

    NASA Astrophysics Data System (ADS)

    Marcus, P. S.; Lee, C.

    1998-06-01

    the wave and vortex behavior in the experiments including the locking of the vortex chains of the eastward jet. The simulations and new model contradict the predictions of a competing, older model of the laboratory flow that is based on a Bickley jet; this raises concerns about previous calculations of Lagrangian mixing in the laboratory experiments that used the Bickley model for the fluid velocity. The new model, simulations and laboratory experiments all show that jets can be formed by the mixing and homogenization of q. The relevance of this to the jets of Jupiter is discussed.

  10. Sangamon field experiments: observations of the diurnal evolution of the planetary boundary layer over land

    SciTech Connect

    Hicks, B.B.; Hess, G.D.; Wesely, M.L.; Yamada, T.; Frenzen, P.; Hart, R.L.; Sisterson, D.L.; Hess, P.E.; Kulhanek, F.C.; Lipschutz, R.C.; Zerbe, G.A.

    1981-09-01

    Two complementary experimental studies of the evolving structure of the lower 2 km of the atmosphere, conducted over farmlands in central Illinois during essentially the same mid-summer weeks of two successive years, are described. The first experiment (21 July - 13 August 1975) investigated the early morning break up of the nocturnal stable layer and the rapid growth of the mixed layer before noon; the second (16 to 30 July 1976) examined the decline of the mixed layer through the late afternoon and evening, and the formation and intensification of the ground-based inversion before midnight. Methods of observation and data reduction are summarized in some detail, and the data obtained in the form of hourly wind and temperature profiles, plus sufficient surface flux information to characterize the lower boundary conditions, are tabulated in a series of appendices. These results constitute complete data sets which may be used to test models of the diurnal evolution of the lower atmosphere.

  11. Monitoring Floods with NASA's ST6 Autonomous Sciencecraft Experiment: Implications on Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Ip, Felipe; Dohm, J. M.; Baker, V. R.; Castano, B.; Chien, S.; Cichy, B.; Davies, A. G.; Doggett, T.; Greeley, R.; Sherwood, R.

    2005-01-01

    NASA's New Millennium Program (NMP) Autonomous Sciencecraft Experiment (ASE) [1-3] has been successfully demonstrated in Earth-orbit. NASA has identified the development of an autonomously operating spacecraft as a necessity for an expanded program of missions exploring the Solar System. The versatile ASE spacecraft command and control, image formation, and science processing software was uploaded to the Earth Observer 1 (EO-1) spacecraft in early 2004 and has been undergoing onboard testing since May 2004 for the near real-time detection of surface modification related to transient geological and hydrological processes such as volcanism [4], ice formation and retreat [5], and flooding [6]. Space autonomy technology developed as part of ASE creates the new capability to autonomously detect, assess, react to, and monitor dynamic events such as flooding. Part of the challenge has been the difficulty to observe flooding in real time at sufficient temporal resolutions; more importantly, it is the large spatial extent of most drainage networks coupled with the size of the data sets necessary to be downlinked from satellites that make it difficult to monitor flooding from space. Below is a description of the algorithms (referred to as ASE Flood water Classifiers) used in tandem with the Hyperion spectrometer instrument on EO-1 to identify flooding and some of the test results.

  12. Reports of planetary geology program, 1976 - 1977. [abstracts

    NASA Technical Reports Server (NTRS)

    Arvidson, R. (Compiler); Wahmann, R. (Compiler); Howard, J. H., III

    1977-01-01

    One hundred seventeen investigations undertaken in the NASA Planetary Geology Program in 1976-1977 are reported in abstract form. Topics discussed include solar system formation; planetary interiors; planetary evolution; asteroids, comets and moons; cratering; volcanic, eolian, fluvial and mass wasting processes; volatiles and the Martian regolith; mapping; and instrument development and techniques. An author index is provided.

  13. Chemical Experiments Measuring ph and Gases on "Planetary" Soil by the HUSAR-5 NXT-based Rover Model

    NASA Astrophysics Data System (ADS)

    Lang, Agota; Bérczi, Szaniszló; Erdélyi, Soma; Nickl, Istvan; Kiss, Daniel; Erdősi, Ferenc; Panyi, Tamas; Szalay, Kristof

    2010-05-01

    program. II: For detecting the gases: We use CZGCO type gas-sensor for the detection of the liberated carbon monoxide or methane. This is a semiconductor based sensor which is heated up to working temperature (ca. 400 °C). The gas is measured as a resistance change signal lead into the NXT. The measured values are observed on the NXT as well as on the "terrestrial control" computer. Construction of the rover in the second mission: the skeleton of the rover was a field-rovering car model. We constructed two arms and a pump from LEGO elements. On the first arm we placed a wireless camera, which could rotate 360°, and also could bend down. The role of the second arm was to stretch and place the indicator ribbon to the surface and move it along a distance to contact with the wet soil. The role of the pump was to pour water on the soil surface. The main idea behind our solution is that water dissolves important chemical components from the soil and the indicator ribbon reports the main chemical characteristics of this chemistry, starting with the pH of the soil. Conclusion: Even the basic experiments can be interesting in the high school's chemistry teaching process if everyday materials are studied. It can be easily connected to planetary surface chemistry, where the soil, the rocks and the atmospheric gases form a common platform with their counterparts on the Earth. Both the experiment and the rover building was a big task for high school students, but they enjoyed the work and learned a lot.

  14. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry

    2014-03-01

    Preface: a personal view of planetary rings; 1. Introduction: the allure of the ringed planets; 2. Studies of planetary rings 1610-2013; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Uranus' rings and moons; 13. Neptune's partial rings; 14. Jupiter's ring-moon system after Galileo and New Horizons; 15. Ring photometry; 16. Dusty rings; 17. Concluding remarks; Afterword; Glossary; References; Index.

  15. The Planetary Project

    NASA Astrophysics Data System (ADS)

    Pataki, Louis P.

    2016-06-01

    This poster presentation presents the Planetary Project, a multi-week simulated research experience for college non-science majors. Students work in research teams of three to investigate the properties of a fictitious planetary system (the “Planetary System”) created each semester by the instructor. The students write team and individual papers in which they use the available data to draw conclusions about planets, other objects or general properties of the Planetary System and in which they compare, contrast and explain the similarities between the objects in the Planetary System and comparable objects in the Solar System.Data about the orbital and physical properties of the planets in the Planetary System are released at the start of the project. Each week the teams request data from a changing pool of available data. For example, in week one pictures of the planets are available. Each team picks one planet and the data (pictures) on that planet are released only to that team. Different data are available in subsequent weeks. Occasionally a news release to all groups reports an unusual occurrence - e.g. the appearance of a comet.Each student acts as principal author for one of the group paper which must contain a description of the week’s data, conclusions derived from that data about the Planetary System and a comparison with the Solar System. Each students writes a final, individual paper on a topic of their choice dealing with the Planetary System in which they follow the same data, conclusion, comparison format. Students “publish” their papers on a class-only restricted website and present their discoveries in class talks. Data are released to all on the website as the related papers are “published.” Additional papers commenting on the published work and released data are encouraged.The successes and problems of the method are presented.

  16. Degassing of reduced carbon from planetary basalts.

    PubMed

    Wetzel, Diane T; Rutherford, Malcolm J; Jacobsen, Steven D; Hauri, Erik H; Saal, Alberto E

    2013-05-14

    Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential. PMID:23569260

  17. Degassing of reduced carbon from planetary basalts

    PubMed Central

    Wetzel, Diane T.; Rutherford, Malcolm J.; Jacobsen, Steven D.; Hauri, Erik H.; Saal, Alberto E.

    2013-01-01

    Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential. PMID:23569260

  18. Chemistry Experiment Measuring (pH) of the ``Planetary'' Soil by the Husar-5 NTX-based Rover Model of the Széchenyi István High School, Sopron, Hungary

    NASA Astrophysics Data System (ADS)

    Lang, A.; Szalay, K.; Erdélyi, S.; Nickl, I.; Panyi, T.; Kiss, D.; Bérczi, Sz.

    2009-03-01

    We report by a detailed description of the experiment built by students on Husar-5 rover model: how the chemical characteristics of the "planetary" soil can be measured by the indicator ribbon method, if we artificially made wet the soil.

  19. Magnetic dynamos in accreting planetary bodies

    NASA Astrophysics Data System (ADS)

    Golabek, Gregor; Labrosse, Stéphane; Gerya, Taras; Morishima, Ryuji; Tackley, Paul

    2013-04-01

    Laboratory measurements revealed ancient remanent magnetization in meteorites [1] indicating the activity of magnetic dynamos in the corresponding meteorite parent body. To study under which circumstances dynamo activity is possible, we use a new methodology to simulate the internal evolution of a planetary body during accretion and differentiation. Using the N-body code PKDGRAV [2] we simulate the accretion of planetary embryos from an initial annulus of several thousand planetesimals. The growth history of the largest resulting planetary embryo is used as an input for the thermomechanical 2D code I2ELVIS [3]. The thermomechanical model takes recent parametrizations of impact processes [4] and of the magnetic dynamo [5] into account. It was pointed out that impacts can not only deposit heat deep into the target body, which is later buried by ejecta of further impacts [6], but also that impacts expose in the crater region originally deep-seated layers, thus cooling the interior [7]. This combination of impact effects becomes even more important when we consider that planetesimals of all masses contribute to planetary accretion. This leads occasionally to collisions between bodies with large ratios between impactor and target mass. Thus, all these processes can be expected to have a profound effect on the thermal evolution during the epoch of planetary accretion and may have implications for the magnetic dynamo activity. Results show that late-formed planetesimals do not experience silicate melting and avoid thermal alteration, whereas in early-formed bodies accretion and iron core growth occur almost simultaneously and a highly variable magnetic dynamo can operate in the interior of these bodies. [1] Weiss, B.P. et al., Science, 322, 713-716, 2008. [2] Richardson, D. C. et al., Icarus, 143, 45-59, 2000. [3] Gerya, T.V and Yuen, D.J., Phys. Earth Planet. Int., 163, 83-105, 2007. [4] Monteux, J. et al., Geophys. Res. Lett., 34, L24201, 2007. [5] Aubert, J. et al

  20. Scientific Objectives and operational Scheme of the Planetary Underground Tool (Pluto) Experiment on the Beagle 2 Mars Lander

    NASA Astrophysics Data System (ADS)

    Richter, L.; Gromov, V.; Kochan, H.; Kosacki, K.; Tokano, T.

    2003-04-01

    The payload of the Beagle 2 lander of ESA's Mars Express mission includes a regolith-penetrating, tethered "Mole" intended for acquisition of several subsurface soil samples from depths between about 10 cm and approximately 1.5 m. These samples will then be analysed by the Gas Analysis Package (GAP) instrument on the lander, primarily with regard to isotopic composition and organic molecules. In addition, a share of each sample can be deposited onto the lander structure to be investigated with instruments mounted on the lander's PAW instrument carrier, such as the Mössbauer and X-ray fluorescence spectrometers and the optical microscope. After giving a brief overview of the experiment design, this paper focuses on the various science objectives addressed by the Beagle 2 Mole system, also referred to as the PLanetary Underground TOol (PLUTO). Apart from its capability to make subsurface regolith samples available to lander-based experiments for the first time on a Mars landing mission, PLUTO will be capable of performing scientific measurements of its own which utilize the Mole's soil penetration process and its temporary residence within the regolith: while it penetrates into the Martian soil by way of soil displacement through the action of an internal hammering mechanism, the Mole will allow mechanical properties of the regolith to be inferred and additionally, a temperature sensor mounted on the Mole will support investigations of soil thermophysical properties and measurements of the subsurface temperature profile. Using a Mole soil penetration theory calibrated by ground-based experiments, regolith bulk density, cohesion, and internal friction angle can be constrained as a function of depth using the Mole penetration path (and retrieval path) vs. time which is measured by a sensor indicating the amount of tether extracted by the PLUTO Mole. The obtained depth profiles of these quantities should provide insight into the depositional history and stratigraphy of

  1. The Planetary Data System Geosciences Node

    NASA Astrophysics Data System (ADS)

    Guinness, Edward A.; Arvidson, Raymond E.; Slavney, Susan

    1996-01-01

    The purpose of the Planetary Data System Geosciences Node is to archive and distribute planetary geosciences datasets relevant to the surfaces and interiors of the terrestrial planets and moons. This objective is accomplished through the following efforts. The Node works with planetary missions to help ensure that data of relevance to the geosciences discipline are properly documented and archived. The Node restores and publishes selected geoscience datasets from past missions on CD-ROM for distribution to the planetary science community. Data archived at the Node are distributed on CD-ROM, magnetic tape, CD-WO, or by electronic transfer over the Internet. The Geo-sciences Node provides information and expert assistance on its data holdings. Derived image, geophysics, microwave, spaceborne thermal, and radio science data are archived at the lead node or at one of the subnodes. Currently, the amount of data archived at the Node is on the order of 500 Gbytes stored on a combination of nearly 800 CD-ROMs and CD-WOs. Current archives within the Node include data from the Magellan and Viking missions, the Geological Remote Sensing Field Experiment, and a collection of radar, altimetry, and gravity datasets for Venus, Mercury, Mars, Earth, and the Moon, together with software to analyze the data. The Node maintains on-line catalogs that enable the science community to search through the Geosciences Node archives and to order selected datasets. Access to the Node's catalogs and on-line datasets is available via the Internet using a remote login or via the World Wide Web (WWW).

  2. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry W.

    2011-07-01

    Preface; 1. Introduction: the allure of ringed planets; 2. Studies of planetary rings 1610-2004; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-Body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Neptune's partial rings; 13. Jupiter's ring-moon system after Galileo; 14. Ring photometry; 15. Dusty rings; 16. Cassini observations; 17. Summary: the big questions; Glossary; References; Index.

  3. Planetary magnetism

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    1980-01-01

    Planetary spacecraft have now probed the magnetic fields of all the terrestrial planets, the moon, Jupiter, and Saturn. These measurements reveal that dynamos are active in at least four of the planets, Mercury, the earth, Jupiter, and Saturn but that Venus and Mars appear to have at most only very weak planetary magnetic fields. The moon may have once possessed an internal dynamo, for the surface rocks are magnetized. The large satellites of the outer solar system are candidates for dynamo action in addition to the large planets themselves. Of these satellites the one most likely to generate its own internal magnetic field is Io.

  4. Planetary astronomy

    NASA Technical Reports Server (NTRS)

    Morrison, David; Hunten, Donald; Ahearn, Michael F.; Belton, Michael J. S.; Black, David; Brown, Robert A.; Brown, Robert Hamilton; Cochran, Anita L.; Cruikshank, Dale P.; Depater, Imke

    1991-01-01

    The authors profile the field of astronomy, identify some of the key scientific questions that can be addressed during the decade of the 1990's, and recommend several facilities that are critically important for answering these questions. Scientific opportunities for the 1990' are discussed. Areas discussed include protoplanetary disks, an inventory of the solar system, primitive material in the solar system, the dynamics of planetary atmospheres, planetary rings and ring dynamics, the composition and structure of the atmospheres of giant planets, the volcanoes of IO, and the mineralogy of the Martian surface. Critical technology developments, proposed projects and facilities, and recommendations for research and facilities are discussed.

  5. Planetary System Physics

    NASA Technical Reports Server (NTRS)

    Peale, S. J.

    2002-01-01

    Contents include a summary of publications followed by their abstracts titeled: 1. On microlensing rates and optical depth toward the Galactic center. 2. Newly discovered brown dwarfs not seen in microlensing timescale frequency distribution? 3. Origin and evolution of the natural satellites. 4. Probing the structure of the galaxy with microlensing. 5. Tides, Encyclopedia of Astronomy and Astrophysics. 6. The Puzzle of the Titan-Hyperion 4:3 Orbital Resonance. 7. On the Validity of the Coagulation Equation and the Nature of Runaway Growth. 8. Making Hyperion. 9. The MESSENGER mission to Mercury: Scientific objectives and implementation. 10. A Survey of Numerical Solutions to the Coagulation. 11. Probability of detecting a planetary companion during a microlensing event. 12. Dynamics and origin of the 2:l orbital resonances of the GJ876 planets. 13. Planetary Interior Structure Revealed by Spin Dynamics. 14. A primordial origin of the Laplace relation among the Galilean Satellites. 15. A procedure for determining the nature of Mercury's core. 16. Secular evolution of hierarchical planetary systems. 17. Tidally induced volcanism. 18. Extrasolar planets and mean motion resonances. 19. Comparison of a ground-based microlensing search for planets with a search from space.

  6. Librational Response of Enceladus to Its Interior Structure

    NASA Astrophysics Data System (ADS)

    Rambaux, N.; Castillo-Rogez, J. C.; Williams, J. G.; Karatekin, O.

    2010-03-01

    We will present the rotational motion of Enceladus perturbed by planetary perturbations and tidal torques and describe the main librations and short librations at 1.37 days amplitude for various interior models (computed with the Andrade model).

  7. The Ganymede Interior Structure, and Magnetosphere Observer (GISMO) Mission Concept

    NASA Astrophysics Data System (ADS)

    Lynch, K. L.; Smith, I. B.; Singer, K. N.; Vogt, M. F.; Blackburn, D. G.; Chaffin, M.; Choukroun, M.; Ehsan, N.; Dibraccio, G. A.; Gibbons, L. J.; Gleeson, D.; Jones, B. A.; Legall, A.; McEnulty, T.; Rampe, E.; Schrader, C.; Seward, L.; Tsang, C. C. C.; Williamson, P.; Castillo, J.; Budney, C.

    2011-03-01

    As part of the 2010 NASA Planetary Science Summer School, the Ganymede Interior, Surface, and Magnetosphere Observer (GISMO) team developed a preliminary satellite design for a science mission to Jupiter's moon Ganymede.

  8. Preparation of a skin equivalent phantom with interior micron-scale vessel structures for optical imaging experiments

    PubMed Central

    Chen, Chen; Klämpfl, Florian; Knipfer, Christian; Riemann, Max; Kanawade, Rajesh; Stelzle, Florian; Schmidt, Michael

    2014-01-01

    A popular alternative of preparing multilayer or microfluidic chip based phantoms could have helped to simulate the subsurface vascular network, but brought inevitable problems. In this work, we describe the preparation method of a single layer skin equivalent tissue phantom containing interior vessel channels, which mimick the superficial microvascular structure. The fabrication method does not disturb the optical properties of the turbiding matrix material. The diameter of the channels reaches a value of 50 μm. The size, as well as the geometry of the generated vessel structures are investigated by using the SD-OCT system. Our preliminary results confirm that fabrication of such a phantom is achievable and reproducible. Prospectively, this phantom is used to calibrate the optical angiographic imaging approaches. PMID:25401027

  9. Planetary quarantine

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The overall objective is to identify those areas of future missions which will be impacted by planetary quarantine (PQ) constraints. The objective of the phase being described was to develop an approach for using decision theory in performing a PQ analysis for a Mariner Jupiter Uranus Mission and to compare it with the traditional approach used for other missions.

  10. Planetary Rings

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    1994-01-01

    Just over two decades ago, Jim Pollack made a critical contribution to our understanding of planetary ring particle properties, and resolved a major apparent paradox between radar reflection and radio emission observations. At the time, particle properties were about all there were to study about planetary rings, and the fundamental questions were, why is Saturn the only planet with rings, how big are the particles, and what are they made of? Since then, we have received an avalanche of observations of planetary ring systems, both from spacecraft and from Earth. Meanwhile, we have seen steady progress in our understanding of the myriad ways in which gravity, fluid and statistical mechanics, and electromagnetism can combine to shape the distribution of the submicron-to-several-meter size particles which comprise ring systems into the complex webs of structure that we now know them to display. Insights gained from studies of these giant dynamical analogs have carried over into improved understanding of the formation of the planets themselves from particle disks, a subject very close to Jim's heart. The now-complete reconnaissance of the gas giant planets by spacecraft has revealed that ring systems are invariably found in association with families of regular satellites, and there is ark emerging perspective that they are not only physically but causally linked. There is also mounting evidence that many features or aspects of all planetary ring systems, if not the ring systems themselves, are considerably younger than the solar system

  11. Planetary radar

    NASA Technical Reports Server (NTRS)

    Taylor, R. M.

    1980-01-01

    The radar astronomy activities supported by the Deep Space Network during June, July, and August 1980 are reported. The planetary bodies observed were Venus, Mercury, and the asteroid Toro. Data were obtained at both S and X band, and the observations were considered successful.

  12. Planetary Geomorphology.

    ERIC Educational Resources Information Center

    Baker, Victor R.

    1984-01-01

    Discusses various topics related to planetary geomorphology, including: research techniques; such geomorphic processes as impact, volcanic, degradational, eolian, and hillslope/mass movement processes; and channels and valleys. Indicates that the subject should be taught as a series of scientific questions rather than scientific results of…

  13. Planetary quarantine

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Developed methodologies and procedures for the reduction of microbial burden on an assembled spacecraft at the time of encapsulation or terminal sterilization are reported. This technology is required for reducing excessive microbial burden on spacecraft components for the purposes of either decreasing planetary contamination probabilities for an orbiter or minimizing the duration of a sterilization process for a lander.

  14. Planetary Radar Astronomy

    NASA Technical Reports Server (NTRS)

    Ostro, Steven J.

    1993-01-01

    Radar is a powerful technique that has furnished otherwise unavailable information about solar system bodies for three decades. The advantages of radar in planetary astronomy result from: (1) the observer's control of all the attributes of the coherent signal used to illuminate the target, especially the wave form's time/frequency modulation and polarization; (2) the ability of radar to resolve objects spatially via measurements of the distribution of echo power in time delay and Doppler frequency; (3) the pronounced degree to which delay-Doppler measurements constrain orbits and spin vectors; and (4) centimeter-to-meter wavelengths, which easily penetrate optically opaque planetary clouds and cometary comae, permit investigation of near-surface macrostructure and bulk density, and are sensitive to high concentrations of metal or, in certain situations, ice. Planetary radar astronomy has primarily involved observations with Earth-based radar telescopes, but also includes some experiments with a spaceborne transmitter or receiver. In addition to providing a wealth of information about the geological and dynamical properties of asteroids, comets, the inner planets, and natural satellites, radar experiments have established the scale of the solar system, have contributed significantly to the accuracy of planetary ephemerides, and have helped to constrain theories of gravitation. This review outlines radar astronomical techniques and describes principal observational results.

  15. The Optical Gravitational Lensing Experiment. Planetary and Low-Luminosity Object Transits in the Carina Fields of the Galactic Disk

    NASA Astrophysics Data System (ADS)

    Udalski, A.; Szewczyk, O.; Zebrun, K.; Pietrzynski, G.; Szymanski, M.; Kubiak, M.; Soszynski, I.; Wyrzykowski, L.

    2002-12-01

    We present results of the second "planetary and low-luminosity object transit" campaign conducted by the OGLE-III survey. Three fields (35' X 35' each) located in the Carina regions of the Galactic disk (l ≈ 290°) were monitored continuously in February-May 2002. About 1150 epochs were collected for each field. The search for low depth transits was conducted on about 103 000 stars with photometry better than 15 mmag. In total, we discovered 62 objects with shallow depth (≤ 0.08 mag) flat-bottomed transits. For each of these objects several individual transits were detected and photometric elements were determined. Also lower limits on radii of the primary and companion were calculated. The 2002 OGLE sample of stars with transiting companions contains considerably more objects that may be Jupiter-sized (R < 1.6 R_Jup) compared to our 2001 sample. There is a group of planetary candidates with the orbital periods close to or shorter than one day. If confirmed as planets, they would be the shortest period extrasolar planetary systems. In general, the transiting objects may be extrasolar planets, brown dwarfs, or M-type dwarfs. One should be, however, aware that in some cases unresolved blends of regular eclipsing stars can mimic transits. Future spectral analysis and eventual determination of the amplitude of radial velocity should allow final classification. High resolution spectroscopic follow-up observations are, therefore, strongly encouraged. All photometric data are available to the astronomical community from the OGLE INTERNET archive.

  16. Planetary quarantine

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Those areas of future missions which will be impacted by planetary quarantine (PQ) constraints were identified. The specific objectives for this reporting period were (1) to perform an analysis of the effects of PQ on an outer planet atmospheric probe, and (2) to prepare a quantitative illustration of spacecraft microbial reduction resulting from exposure to space environments. The Jupiter Orbiter Probe mission was used as a model for both of these efforts.

  17. Planetary Society

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Carl Sagan, Bruce Murray and Louis Friedman founded the non-profit Planetary Society in 1979 to advance the exploration of the solar system and to continue the search for extraterrestrial life. The Society has its headquarters in Pasadena, California, but is international in scope, with 100 000 members worldwide, making it the largest space interest group in the world. The Society funds a var...

  18. Planetary engineering

    NASA Astrophysics Data System (ADS)

    Pollack, James B.; Sagan, Carl

    Assuming commercial fusion power, heavy lift vehicles and major advances in genetic engineering, the authors survey possible late-21st century methods of working major transformations in planetary environments. Much more Earthlike climates may be produced on Mars by generating low freezing point greenhouse gases from indigenous materials; on Venus by biological conversion of CO2 to graphite, by canceling the greenhouse effect with high-altitude absorbing fine particles, or by a sunshield at the first Lagrangian point; and on Titan by greenhouses and/or fusion warming. However, in our present state of ignorance we cannot guarantee a stable endstate or exclude unanticipated climatic feedbacks or other unintended consequences. Moreover, as the authors illustrate by several examples, many conceivable modes of planetary engineering are so wasteful of scarce solar system resources and so destructive of important scientific information as to raise profound ethical issues, even if they were economically feasible, which they are not. Global warming on Earth may lead to calls for mitigation by planetary engineering, e.g., emplacement and replenishment of anti-greenhouse layers at high altitudes, or sunshields in space. But here especially we must be concerned about precision, stability, and inadvertent side-effects. The safest and most cost-effective means of countering global warming - beyond, e.g., improved energy efficiency, CFC bans and alternative energy sources - is the continuing reforestation of approximately 2 times 107 sq km of the Earth's surface. This can be accomplished with present technology and probably at the least cost.

  19. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Gordon, M. K.; Araki, S.; Black, G. J.; Bosh, A. S.; Brahic, A.; Brooks, S. M.; Charnoz, S.; Colwell, J. E.; Cuzzi, J. N.; Dones, L.; Durisen, R. H.; Esposito, L. W.; Ferrari, C.; Festou, M.; French, R. G.; Giuliatti-Winter, S. M.; Graps, A. L.; Hamilton, D. P.; Horanyi, M.; Karjalainen, R. M.; Krivov, A. V.; Krueger, H.; Larson, S. M.; Levison, H. F.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Namouni, F.; Nicholson, P. D.; Olkin, C. B.; Poulet, F.; Rappaport, N. J.; Salo, H. J.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Stewart, G. R.; Yanamandra-Fisher, P.

    2002-08-01

    The past two decades have witnessed dramatic changes in our view and understanding of planetary rings. We now know that each of the giant planets in the Solar System possesses a complex and unique ring system. Recent studies have identified complex gravitational interactions between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto, or collisions between, parent bodies. Yet, as far as we have come, our understanding is far from complete. The fundamental questions confronting ring scientists at the beginning of the twenty-first century are those regarding the origin, age and evolution of the various ring systems, in the broadest context. Understanding the origin and age requires us to know the current ring properties, and to understand the dominant evolutionary processes and how they influence ring properties. Here we discuss a prioritized list of the key questions, the answers to which would provide the greatest improvement in our understanding of planetary rings. We then outline the initiatives, missions, and other supporting activities needed to address those questions, and recommend priorities for the coming decade in planetary ring science.

  20. Planetary engineering

    NASA Technical Reports Server (NTRS)

    Pollack, James B.; Sagan, Carl

    1991-01-01

    Assuming commercial fusion power, heavy lift vehicles and major advances in genetic engineering, the authors survey possible late-21st century methods of working major transformations in planetary environments. Much more Earthlike climates may be produced on Mars by generating low freezing point greenhouse gases from indigenous materials; on Venus by biological conversion of CO2 to graphite, by canceling the greenhouse effect with high-altitude absorbing fine particles, or by a sunshield at the first Lagrangian point; and on Titan by greenhouses and/or fusion warming. However, in our present state of ignorance we cannot guarantee a stable endstate or exclude unanticipated climatic feedbacks or other unintended consequences. Moreover, as the authors illustrate by several examples, many conceivable modes of planetary engineering are so wasteful of scarce solar system resources and so destructive of important scientific information as to raise profound ethical issues, even if they were economically feasible, which they are not. Global warming on Earth may lead to calls for mitigation by planetary engineering, e.g., emplacement and replenishment of anti-greenhouse layers at high altitudes, or sunshields in space. But here especially we must be concerned about precision, stability, and inadvertent side-effects. The safest and most cost-effective means of countering global warming - beyond, e.g., improved energy efficiency, CFC bans and alternative energy sources - is the continuing reforestation of approximately 2 times 107 sq km of the Earth's surface. This can be accomplished with present technology and probably at the least cost.

  1. A bibliography of planetary geology principal investigators and their associates, 1976-1978

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This bibliography cites publications submitted by 484 principal investigators and their associates who were supported through NASA's Office of Space Sciences Planetary Geology Program. Subject classifications include: solar system formation, comets, and asteroids; planetary satellites, planetary interiors, geological and geochemical constraints on planetary evolution; impact crater studies, volcanism, eolian studies, fluvian studies, Mars geological mapping; Mercury geological mapping; planetary cartography; and instrument development and techniques. An author/editor index is provided.

  2. Planetary Doppler Imaging

    NASA Astrophysics Data System (ADS)

    Murphy, N.; Jefferies, S.; Hart, M.; Hubbard, W. B.; Showman, A. P.; Hernandez, G.; Rudd, L.

    2014-12-01

    Determining the internal structure of the solar system's gas and ice giant planets is key to understanding their formation and evolution (Hubbard et al., 1999, 2002, Guillot 2005), and in turn the formation and evolution of the solar system. While internal structure can be constrained theoretically, measurements of internal density distributions are needed to uncover the details of the deep interior where significant ambiguities exist. To date the interiors of giant planets have been probed by measuring gravitational moments using spacecraft passing close to, or in orbit around the planet. Gravity measurements are effective in determining structure in the outer envelope of a planet, and also probing dynamics (e.g. the Cassini and Juno missions), but are less effective in probing deep structure or the presence of discrete boundaries. A promising technique for overcoming this limitation is planetary seismology (analogous to helioseismology in the solar case), postulated by Vorontsov, 1976. Using trapped pressure waves to probe giant planet interiors allows insight into the density and temperature distribution (via the sound speed) down to the planetary core, and is also sensitive to sharp boundaries, for example at the molecular to metallic hydrogen transition or at the core-envelope interface. Detecting such boundaries is not only important in understanding the overall structure of the planet, but also has implications for our understanding of the basic properties of matter at extreme pressures. Recent Doppler measurements of Jupiter by Gaulme et al (2011) claimed a promising detection of trapped oscillations, while Hedman and Nicholson (2013) have shown that trapped waves in Saturn cause detectable perturbations in Saturn's C ring. Both these papers have fueled interest in using seismology as a tool for studying the solar system's giant planets. To fully exploit planetary seismology as a tool for understanding giant planet structure, measurements need to be made

  3. New Interface for Accessing Archived European Space Agency Planetary Science Data, Such as the New Venus Express Atmospheric Drag Experiment Data Set

    NASA Astrophysics Data System (ADS)

    Grotheer, E.; Barbarisi, I.; Rios, C.; Macfarlane, A. J.; Docasal, R.; Arviset, C.; Besse, S.; Heather, D.; Gonzalez, J.; De Marchi, G.; Martinez, S.; Lim, T.; Fraga, D.

    2015-12-01

    All Venus Express (VEX) instruments delivered their data products according to the Planetary Data System version 3 (PDS3) standard, and the atmospheric drag experiment (ADE) data was no exception. The European Space Agency's (ESA) Planetary Science Archive (PSA), which can be accessed at www.rssd.esa.int/PSA, is being upgraded to make PDS4 data available from newer missions such as ExoMars and BepiColombo. Thus, the PSA development team has been working to ensure that the legacy PDS3 data will be accessible via the new interface as well. We will preview some of the new methods of accessing legacy VEX data via the new interface, with a focus being placed on the ADE data set. We will show how the ADE data can be accessed using Geographic Information Systems (GIS) and our plans for making this and other data sets compatible with the Virtual European Solar and Planetary Access (VESPA) project for creating a virtual observatory. From February 2010 through March 2014, ESA's Venus Express mission conducted 11 ADE campaigns. During these observation campaigns, VEX's pericenter was in the range of 165 to 190 km, while the spacecraft was near Venus' North pole, and the entire spacecraft was used to make in situ measurements of the atmospheric density. This was done by rotating the solar panels in a manner that somewhat resembles a windmill. Also, VEX 's attitude and orbit control system was tasked with maintaining the spacecraft in a 3-axis stabilized mode during these pericenter passes. The torques that the reaction wheels had to exert to maintain this attitude were then analyzed to yield density readings.

  4. Simulation of large scale motions and small scale structures in planetary atmospheres and oceans: From laboratory to space experiments on ISS

    NASA Astrophysics Data System (ADS)

    Egbers, Christoph; Futterer, Birgit; Zaussinger, Florian; Harlander, Uwe

    2014-05-01

    Baroclinic waves are responsible for the transport of heat and momentum in the oceans, in the Earth's atmosphere as well as in other planetary atmospheres. The talk will give an overview on possibilities to simulate such large scale as well as co-existing small scale structures with the help of well defined laboratory experiments like the baroclinic wave tank (annulus experiment). The analogy between the Earth's atmosphere and the rotating cylindrical annulus experiment only driven by rotation and differential heating between polar and equatorial regions is obvious. From the Gulf stream single vortices seperate from time to time. The same dynamics and the co-existence of small and large scale structures and their separation can be also observed in laboratory experiments as in the rotating cylindrical annulus experiment. This experiment represents the mid latitude dynamics quite well and is part as a central reference experiment in the German-wide DFG priority research programme ("METSTRÖM", SPP 1276) yielding as a benchmark for lot of different numerical methods. On the other hand, those laboratory experiments in cylindrical geometry are limited due to the fact, that the surface and real interaction between polar and equatorial region and their different dynamics can not be really studied. Therefore, I demonstrate how to use the very successful Geoflow I and Geoflow II space experiment hardware on ISS with future modifications for simulations of small and large scale planetary atmospheric motion in spherical geometry with differential heating between inner and outer spheres as well as between the polar and equatorial regions. References: Harlander, U., Wenzel, J., Wang, Y., Alexandrov, K. & Egbers, Ch., 2012, Simultaneous PIV- and thermography measurements of partially blocked flow in a heated rotating annulus, Exp. in Fluids, 52 (4), 1077-1087 Futterer, B., Krebs, A., Plesa, A.-C., Zaussinger, F., Hollerbach, R., Breuer, D. & Egbers, Ch., 2013, Sheet-like and

  5. Planetary atlases

    NASA Technical Reports Server (NTRS)

    Batson, R. M.; Inge, J. L.; Morgan, H. F.

    1991-01-01

    Two kinds of planetary map atlases are in production. Atlases of the first kind contain reduced-scale versions of maps in hard-bound books with dimensions of 11 x 14 inches. These new atlases are intended to: (1) provide concise but comprehensive references to the geography of the planets needed by planetary scientists and others; and (2) allow inexpensive access to the planetary map dataset without requiring acquisition and examination of tens or hundreds of full-size map sheets. Two such atlases have been published and a third is in press. Work was begun of an Atlas of the Satellite of the Outer Planets. The second kind of atlas is a popular or semi-technical version designed for commercial publication and distribution. The first edition, The Atlas of the Solar System, is nearly ready for publication. New funding and contracting constraints now make it unlikely that the atlas can be published in the format originally planned. Currently, the possibility of publishing the maps through the U.S. Geological Survey as a series of folios in the I-map series is being explored. The maps are global views of each solid-surface body of the Solar System. Each map shows airbrushed relief, albedo, and, where available, topography. A set of simplified geologic maps is also included. All of the maps are on equal-area projections. Scales are 1:40,000,000 for the Earth and Venus; 1:2,000,000 for the Saturnian satellites Mimas and Enceladus and the Uranian satellite Miranda; 1:100,000 for the Martian satellites, Phobos and Deimos; and 1:10,000,000 for all other bodies.

  6. Planetary magnetospheres

    NASA Technical Reports Server (NTRS)

    Stern, D. P.; Ness, N. F.

    1981-01-01

    A concise overview is presented of our understanding of planetary magnetospheres (and in particular, of that of the Earth), as of the end of 1981. Emphasis is placed on processes of astrophysical interest, e.g., on particle acceleration, collision-free shocks, particle motion, parallel electric fields, magnetic merging, substorms, and large scale plasma flows. The general morphology and topology of the Earth's magnetosphere are discussed, and important results are given about the magnetospheres of Jupiter, Saturn and Mercury, including those derived from the Voyager 1 and 2 missions and those related to Jupiter's satellite Io. About 160 references are cited, including many reviews from which additional details can be obtained.

  7. Planetary Volcanism

    NASA Technical Reports Server (NTRS)

    Antonenko, I.; Head, J. W.; Pieters, C. W.

    1998-01-01

    The final report consists of 10 journal articles concerning Planetary Volcanism. The articles discuss the following topics: (1) lunar stratigraphy; (2) cryptomare thickness measurements; (3) spherical harmonic spectra; (4) late stage activity of volcanoes on Venus; (5) stresses and calderas on Mars; (6) magma reservoir failure; (7) lunar mare basalt volcanism; (8) impact and volcanic glasses in the 79001/2 Core; (9) geology of the lunar regional dark mantle deposits; and (10) factors controlling the depths and sizes of magma reservoirs in Martian volcanoes.

  8. Planetary astronomy

    NASA Technical Reports Server (NTRS)

    Smith, Harlan J.

    1991-01-01

    Lunar-based astronomy offers major prospects for solar system research in the coming century. In addition to active advocacy of both ground-based and Lunar-based astronomy, a workshop on the value of asteroids as a resource for man is being organized. The following subject areas are also covered: (1) astrophysics from the Moon (composition and structure of planetary atmospheres); (2) a decade of cost-reduction in Very Large Telescopes (the SST as prototype of special-purpose telescopes); and (3) a plan for development of lunar astronomy.

  9. Planetary Dynamos

    NASA Technical Reports Server (NTRS)

    Busse, F. H.

    1985-01-01

    The MAGSAT-program has added significantly to our knowledge of planetary magnetism. The accuracy of observations has been improved such that a reliable extrapolation of the magnetic field to the core surface is now much more feasible than it has been before, and the prospect of further MAGSAT missions raises the expectation that the time dependence of the geomagnetic field will be known with similar accuracy in the future. In the research support it has been attempted to develop dynamo theory with these applications in mind.

  10. Numerical investigation of laser radiation conversion to X rays in experiments with spherical boxes with interior coatings of different materials

    SciTech Connect

    Bondarenko, S V; Dolgoleva, G V; Novikova, E A

    2010-08-03

    The dynamics of laser and X-ray radiation fields in experiments with spherical boxes was numerically investigated in a sector approximation using the SND-LIRA numerical code. The experiments were performed on the Iskra-5 laser facility at a wavelength {lambda}=0.657 {mu}m (the second harmonic of iodine laser radiation). The characteristics of X-ray generation were investigated with the inner surface of a converter box coated with different-Z materials (Au, Cu, Mg). With lowering Z, the laser energy absorption coefficient k{sub a} decreases and there occurs a lowering of the effective X-ray radiation temperature. Our calculations reveal a strong dependence of the results on the electron free-streaming flux limitation f. In particular, on lowering f from 0.1 to 0.03 for a conventional box with a gold coating, the coefficient k{sub a} decreases from 0.83 to 0.5 and the peak X-ray radiation temperature drops from 170 to 150eV. In these calculations, the rms nonuniformity of the X-ray irradiation of a capsule with thermonuclear fuel amounted to 1%-3%.

  11. Planetary Evolution, Habitability and Life

    NASA Astrophysics Data System (ADS)

    Tilman, Spohn; Breuer, Doris; de Vera, Jean-Pierre; Jaumann, Ralf; Kuehrt, Ekkehard; Möhlmann, Diedrich; Rauer, Heike; Richter, Lutz

    A Helmholtz Alliance has been established to study the interactions between life and the evo-lution of planets. The approach goes beyond current studies in Earth-System Sciences by including the entire planet from the atmosphere to the deep interior, going beyond Earth to include other Earth-like planets such as Mars and Venus and satellites in the solar system where ecosystems may exist underneath thick ice shells,considering other solar systems. The approach includes studies of the importance of plate tectonics and other tectonic regimes such as single plate tectonics for the development and for sustaining life and asks the question: If life can adapt to a planet, can a planet adapt to life? Can life be seen as a geological process and if so, can life shape the conditions on a planet such that life can flourish? The vision goes beyond the solar system by including the challenges that life would face in other solar systems. The Alliance uses theoretical modelling of feedback cycles and coupled planetary atmosphere and interior processes. These models are based on the results of remote sensing of planetary surfaces and atmospheres, laboratory studies on (meteorite) samples from other planets and on studies of life under extreme conditions. The Alliance uses its unique capabilities in remote sensing and in-situ exploration to prepare for empirical studies of the parameters affecting habitability. The Alliance aims to establish a network infrastructure in Germany to enable the most ad-vanced research in planetary evolution studies by including life as a planetary process. Finding extraterrestrial life is a task of fundamental importance to mankind, and its fulfilment will be philosophically profound. Evaluating the interactions between planetary evolution and life will help to put the evolution of our home planet (even anthropogenic effects) into perspective.

  12. Planetary Astronomy

    NASA Technical Reports Server (NTRS)

    Stern, S. Alan

    1998-01-01

    This 1-year project was an augmentation grant to my NASA Planetary Astronomy grant. With the awarded funding, we accomplished the following tasks: (1) Conducted two NVK imaging runs in conjunction with the ILAW (International Lunar Atmosphere Week) Observing Campaigns in 1995 and 1997. In the first run, we obtained repeated imaging sequences of lunar Na D-line emission to better quantify the temporal variations detected in earlier runs. In the second run we obtained extremely high resolution (R=960.000) Na line profiles using the 4m AAT in Australia. These data are being analyzed under our new 3-year Planetary Astronomy grant. (2) Reduced, analyzed, and published our March 1995 spectroscopic dataset to detect (or set stringent upper limits on) Rb. Cs, Mg. Al. Fe, Ba, Ba. OH, and several other species. These results were reported in a talk at the LPSC and in two papers: (1) A Spectroscopic Survey of Metallic Abundances in the Lunar Atmosphere. and (2) A Search for Magnesium in the Lunar Atmosphere. Both reprints are attached. Wrote up an extensive, invited Reviews of Geophysics review article on advances in the study of the lunar atmosphere. This 70-page article, which is expected to appear in print in 1999, is also attached.

  13. Planetary Habitability

    NASA Technical Reports Server (NTRS)

    Kasting, James F.

    1997-01-01

    This grant was entitled 'Planetary Habitability' and the work performed under it related to elucidating the conditions that lead to habitable, i.e. Earth-like, planets. Below are listed publications for the past two and a half years that came out of this work. The main thrusts of the research involved: (1) showing under what conditions atmospheric O2 and O3 can be considered as evidence for life on a planet's surface; (2) determining whether CH4 may have played a role in warming early Mars; (3) studying the effect of varying UV levels on Earth-like planets around different types of stars to see whether this would pose a threat to habitability; and (4) studying the effect of chaotic obliquity variations on planetary climates and determining whether planets that experienced such variations might still be habitable. Several of these topics involve ongoing research that has been carried out under a new grant number, but which continues to be funded by NASA's Exobiology program.

  14. Orbits and Interiors of Planets

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin

    2012-05-01

    The focus of this thesis is a collection of problems of timely interest in orbital dynamics and interior structure of planetary bodies. The first three chapters are dedicated to understanding the interior structure of close-in, gaseous extrasolar planets (hot Jupiters). In order to resolve a long-standing problem of anomalously large hot Jupiter radii, we proposed a novel magnetohydrodynamic mechanism responsible for inflation. The mechanism relies on the electro-magnetic interactions between fast atmospheric flows and the planetary magnetic field in a thermally ionized atmosphere, to induce electrical currents that flow throughout the planet. The resulting Ohmic dissipation acts to maintain the interior entropies, and by extension the radii of hot Jupiters at an enhanced level. Using self-consistent calculations of thermal evolution of hot Jupiters under Ohmic dissipation, we demonstrated a clear tendency towards inflated radii for effective temperatures that give rise to significant ionization of K and Na in the atmosphere, a trend fully consistent with the observational data. Furthermore, we found that in absence of massive cores, low-mass hot Jupiters can over-flow their Roche-lobes and evaporate on Gyr time-scales, possibly leaving behind small rocky cores. Chapters four through six focus on the improvement and implications of a model for orbital evolution of the solar system, driven by dynamical instability (termed the "Nice" model). Hydrodynamical studies of the orbital evolution of planets embedded in protoplanetary disks suggest that giant planets have a tendency to assemble into multi-resonant configurations. Following this argument, we used analytical methods as well as self-consistent numerical N-body simulations to identify fully-resonant primordial states of the outer solar system, whose dynamical evolutions give rise to orbital architectures that resemble the current solar system. We found a total of only eight such initial conditions, providing

  15. Advanced planetary analyses. [for planetary mission planning

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The results are summarized of research accomplished during this period concerning planetary mission planning are summarized. The tasks reported include the cost estimations research, planetary missions handbook, and advanced planning activities.

  16. Non-planetary Science from Planetary Missions

    NASA Astrophysics Data System (ADS)

    Elvis, M.; Rabe, K.; Daniels, K.

    2015-12-01

    Planetary science is naturally focussed on the issues of the origin and history of solar systems, especially our own. The implications of an early turbulent history of our solar system reach into many areas including the origin of Earth's oceans, of ores in the Earth's crust and possibly the seeding of life. There are however other areas of science that stand to be developed greatly by planetary missions, primarily to small solar system bodies. The physics of granular materials has been well-studied in Earth's gravity, but lacks a general theory. Because of the compacting effects of gravity, some experiments desired for testing these theories remain impossible on Earth. Studying the behavior of a micro-gravity rubble pile -- such as many asteroids are believed to be -- could provide a new route towards exploring general principles of granular physics. These same studies would also prove valuable for planning missions to sample these same bodies, as techniques for anchoring and deep sampling are difficult to plan in the absence of such knowledge. In materials physics, first-principles total-energy calculations for compounds of a given stoichiometry have identified metastable, or even stable, structures distinct from known structures obtained by synthesis under laboratory conditions. The conditions in the proto-planetary nebula, in the slowly cooling cores of planetesimals, and in the high speed collisions of planetesimals and their derivatives, are all conditions that cannot be achieved in the laboratory. Large samples from comets and asteroids offer the chance to find crystals with these as-yet unobserved structures as well as more exotic materials. Some of these could have unusual properties important for materials science. Meteorites give us a glimpse of these exotic materials, several dozen of which are known that are unique to meteorites. But samples retrieved directly from small bodies in space will not have been affected by atmospheric entry, warmth or

  17. Planetary geosciences, 1989-1990

    NASA Technical Reports Server (NTRS)

    Zuber, Maria T. (Editor); James, Odette B. (Editor); Lunine, Jonathan I. (Editor); Macpherson, Glenn J. (Editor); Phillips, Roger J. (Editor)

    1992-01-01

    NASA's Planetary Geosciences Programs (the Planetary Geology and Geophysics and the Planetary Material and Geochemistry Programs) provide support and an organizational framework for scientific research on solid bodies of the solar system. These research and analysis programs support scientific research aimed at increasing our understanding of the physical, chemical, and dynamic nature of the solid bodies of the solar system: the Moon, the terrestrial planets, the satellites of the outer planets, the rings, the asteroids, and the comets. This research is conducted using a variety of methods: laboratory experiments, theoretical approaches, data analysis, and Earth analog techniques. Through research supported by these programs, we are expanding our understanding of the origin and evolution of the solar system. This document is intended to provide an overview of the more significant scientific findings and discoveries made this year by scientists supported by the Planetary Geosciences Program. To a large degree, these results and discoveries are the measure of success of the programs.

  18. “Seeing” and “feeling” architecture: how bodily self-consciousness alters architectonic experience and affects the perception of interiors

    PubMed Central

    Pasqualini, Isabella; Llobera, Joan; Blanke, Olaf

    2013-01-01

    Over the centuries architectural theory evolved several notions of embodiment, proposing in the nineteenth and twentieth century that architectonic experience is related to physiological responses of the observer. Recent advances in the cognitive neuroscience of embodiment (or bodily self-consciousness) enable empirical studies of architectonic embodiment. Here, we investigated how architecture modulates bodily self-consciousness by adapting a video-based virtual reality (VR) setup previously used to investigate visuo-tactile mechanisms of bodily self-consciousness. While standing in two different interiors, participants were filmed from behind and watched their own virtual body online on a head-mounted display (HMD). Visuo-tactile strokes were applied in synchronous or asynchronous mode to the participants and their virtual body. Two interiors were simulated in the laboratory by placing the sidewalls either far or near from the participants, generating a large and narrow room. We tested if bodily self-consciousness was differently modulated when participants were exposed to both rooms and whether these changes depend on visuo-tactile stimulation. We measured illusory touch, self-identification, and performed length estimations. Our data show that synchronous stroking of the physical and the virtual body induces illusory touch and self-identification with the virtual body, independent of room-size. Moreover, in the narrow room we observed weak feelings of illusory touch with the sidewalls and of approaching walls. These subjective changes were complemented by a stroking-dependent modulation of length estimation only in the narrow room with participants judging the room-size more accurately during conditions of illusory self-identification. We discuss our findings and previous notions of architectonic embodiment in the context of the cognitive neuroscience of bodily self-consciousness and propose an empirical framework grounded in architecture, cognitive

  19. Enabling Planetary Geodesy With the Deep Space Network

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  20. Origin and evolution of planetary and satellite atmospheres

    SciTech Connect

    Atreya, S.K.; Pollack, J.B.; Matthews, M.S.

    1989-01-01

    The present volume on the origin and evolution of planet and satellite atmospheres discusses the chemistry of interstellar gas and grains, planetary accretion, cometary composition, the inventories of asteroid volatiles, key similarities and differences among the terrestrial planets' atmospheric compositions, and planets' atmospheric escape and water loss. Also discussed are planetary atmosphere-planetary interior evolutionary coupling, the atmospheric composition of the outer planets, the structure and composition of giant planet interiors, the tenuous atmosphere of Io, the sources of the atmospheres of the outer solar system's satellites, the present state and chemical evolution of the Titan, Triton, and Pluto atmospheres, and the thermal structure and heat balance of the outer planets.

  1. European Network of Geophysical Planetary Observatories

    NASA Astrophysics Data System (ADS)

    Lognonne, P.; Spohn, T.; Dehant, V.; Giardini, D.; Pengo Team

    Despite 40 years of planetary exploration, very little is known about the deep interior of the planets. The composition and size of the Moon's core is not well known, due to the location of all Apollo seismic stations on the near side. For Mars, even basic parameters like the state and size of the core, the thickness of the crust, and the depth of phase discontinuities are unknown. These informations are however crucial to understand planetary formation and evolution. A crucial step before the start of Cosmic vision, will be the GEP pathfinder network payload onboard ExoMars, able to retrieve the science lost by the failure of the Mars96's small stations and to get other exciting geophysical observations, such as tides, geodesy and heat flux. But we also hope that Cosmic vision will be able to perform new steps, including some of the projects extensively studied during Horizon 2000+ and never implemented (e.g. MarsNet, InterMarsnet). We propose therefore for Europe two major initiatives despite their difference of size in a sequence of a smart size and a medium size mission, the later being related to international collaboration or collaboration with ESA's Human Flight activities. These two initiatives are: (1) A Smart size contribution to future ESA, US or Chinese robotic landers or Human mission to the Moon with the development and provision of a new generation of Autonomous Lunar Surface Experiment Package (ALSEP), comparable to the ALSEP package deployed by NASA during the Apollo missions. In addition to the science objectives, the major technological objective will be the development and flight-test of long lived power sources possibly compatible with international missions. (2) A Medium size mission for a Long-lived, dense seismic network on Mars in order to determine the three-dimensional structure of the interior and possibly the Martian convection regime. Despite their differences in size and budget, both missions will in fact be able to address network

  2. Planetary Protection Constraints For Planetary Exploration and Exobiology

    NASA Astrophysics Data System (ADS)

    Debus, A.; Bonneville, R.; Viso, M.

    According to the article IX of the OUTER SPACE TREATY (London / Washington January 27., 1967) and in the frame of extraterrestrial missions, it is required to preserve planets and Earth from contamination. For ethical, safety and scientific reasons, the space agencies have to comply with the Outer Space Treaty and to take into account the related planetary protection Cospar recommendations. Planetary protection takes also into account the protection of exobiological science, because the results of life detection experimentations could have impacts on planetary protection regulations. The validation of their results depends strongly of how the samples have been collected, stored and analyzed, and particularly of their biological and organic cleanliness. Any risk of contamination by organic materials, chemical coumpounds and by terrestrial microorganisms must be avoided. A large number of missions is presently scheduled, particularly on Mars, in order to search for life or traces of past life. In the frame of such missions, CNES is building a planetary protection organization in order handle and to take in charge all tasks linked to science and engineering concerned by planetary protection. Taking into account CNES past experience in planetary protection related to the Mars 96 mission, its planned participation in exobiological missions with NASA as well as its works and involvement in Cospar activities, this paper will present the main requirements in order to avoid celestial bodies biological contamination, focussing on Mars and including Earth, and to protect exobiological science.

  3. A study of helicopter interior noise reduction

    NASA Technical Reports Server (NTRS)

    Howlett, J. T.; Clevenson, S. A.

    1975-01-01

    The interior noise levels of existing helicopters are discussed along with an ongoing experimental program directed towards reducing these levels. Results of several noise and vibration measurements on Langley Research Center's Civil Helicopter Research Aircraft are presented, including measurements taken before and after installation of an acoustically-treated cabin. The predominant noise source in this helicopter is the first stage planetary gear-clash in the main gear box, both before and after installation of the acoustically treated cabin. Noise reductions of up to 20 db in some octave bands may be required in order to obtain interior noise levels comparable to commercial jet transports.

  4. INTERIOR MODELS OF URANUS AND NEPTUNE

    SciTech Connect

    Helled, Ravit; Schubert, Gerald; Anderson, John D.; Podolak, Morris E-mail: schubert@ucla.edu E-mail: morris@tau.ac.il

    2011-01-01

    'Empirical' models (pressure versus density) of Uranus and Neptune interiors constrained by the gravitational coefficients J{sub 2}, J{sub 4}, the planetary radii and masses, and Voyager solid-body rotation periods are presented. The empirical pressure-density profiles are then interpreted in terms of physical equations of state of hydrogen, helium, ice (H{sub 2}O), and rock (SiO{sub 2}) to test the physical plausibility of the models. The compositions of Uranus and Neptune are found to be similar with somewhat different distributions of the high-Z material. The big difference between the two planets is that Neptune requires a non-solar envelope, while Uranus is best matched with a solar composition envelope. Our analysis suggests that the heavier elements in both Uranus' and Neptune's interior might increase gradually toward the planetary centers. Indeed it is possible to fit the gravitational moments without sharp compositional transitions.

  5. Planetary nebulae

    NASA Astrophysics Data System (ADS)

    Gieseking, F.

    1983-02-01

    The first planetary nebula (PN) was discovered by Darquier in 1779. In 1981, a compilation of galactic PN listed a total of 1455 objects. Outside the Milky Way Galaxy, PN are currently known in the Magellanic Clouds and in several members of the local group of galaxies. The PN have a rich emission-line spectrum, which makes it possible to recognize them at large distances. A central stellar object can be observed within the nebula. In 1927, spectral lines at 4959 A and 5007 A emitted by the PN could finally be identified as 'forbidden lines' of O(++). The life expectancy of a PN, estimated on the basis of the observed expansion rate, is only about 30,000 years. The PN have a number of interesting characteristics which are partly related to the high effective temperature and luminosity of the central stars, the presence of a particle system under extreme physical conditions, and the stellar material provided by the PN for the interstellar medium. Attention is given to the determination of the distance of PN, the Shklovsky distances, and two mysterious aspects related to the spectrum

  6. Planetary nomenclature

    NASA Technical Reports Server (NTRS)

    Strobell, M. E.; Masursky, Harold

    1987-01-01

    In fiscal 1986, names were chosen for prominent features on the five previously known Uranian satellites and for features on the largest of the 10 satellites discovered by Voyager 2. The names of the five large satellites are taken mostly from Shakespeare, and most are spirits; therefore, Shakespearean and spirit themes were used to choose names for topographic features on the satellites. Crater names and most other feature names on Miranda, Oberon, and Titania are from Shakespeare; features on Ariel are named for bright spirits and those on Umbriel for dark, all taken from universal mythology. Preliminary coordinates for these features are derived from shaded relief maps of the satellites to be published in 1987. Orbital elements have been established for the 10 new satellites, and a paper describing this work is in progress; satellite positions are under review by Commission 16 of the IAU. The moon 1985 U1 is informally designated Puck. The nine small satellites discovered in 1986 are to be named for Shakespearean heroines; these names are to be listed in the 1987 edition of the Annual Gazetteer of Planetary Nomenclature.

  7. Proceedings of the 38th Lunar and Planetary Science Conference

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The sessions in the conference include: Titan, Mars Volcanism, Mars Polar Layered Deposits, Early Solar System Isotopes, SPECIAL SESSION: Mars Reconnaissance Orbiter: New Ways of Studying the Red Planet, Achondrites: Exploring Oxygen Isotopes and Parent-Body Processes, Solar System Formation and Evolution, SPECIAL SESSION: SMART-1, . Impact Cratering: Observations and Experiments, SPECIAL SESSION: Volcanism and Tectonism on Saturnian Satellites, Solar Nebula Composition, Mars Fluvial Geomorphology, Asteroid Observations: Spectra, Mostly, Mars Sediments and Geochemistry: View from the Surface, Mars Tectonics and Crustal Dichotomy, Stardust: Wild-2 Revealed, Impact Cratering from Observations and Interpretations, Mars Sediments and Geochemistry: The Map View, Chondrules and Their Formation, Enceladus, Asteroids and Deep Impact: Structure, Dynamics, and Experiments, Mars Surface Process and Evolution, Martian Meteorites: Nakhlites, Experiments, and the Great Shergottite Age Debate, Stardust: Mainly Mineralogy, Astrobiology, Wind-Surface Interactions on Mars and Earth, Icy Satellite Surfaces, Venus, Lunar Remote Sensing, Space Weathering, and Impact Effects, Interplanetary Dust/Genesis, Mars Cratering: Counts and Catastrophes?, Chondrites: Secondary Processes, Mars Sediments and Geochemistry: Atmosphere, Soils, Brines, and Minerals, Lunar Interior and Differentiation, Mars Magnetics and Atmosphere: Core to Ionosphere, Metal-rich Chondrites, Organics in Chondrites, Lunar Impacts and Meteorites, Presolar/Solar Grains, Topics for Print Only papers are: Outer Planets/Satellites, Early Solar System, Interplanetary Dust, Comets and Kuiper Belt Objects, Asteroids and Meteoroids, Chondrites, Achondrites, Meteorite Related, Mars Reconnaissance Orbiter, Mars, Astrobiology, Planetary Differentiation, Impacts, Mercury, Lunar Samples and Modeling, Venus, Missions and Instruments, Global Warming, Education and Public Outreach, Poster sessions are: Asteroids/Kuiper Belt Objects

  8. Exobiological implications of dust aggregation in planetary atmospheres: An experiment for the gas-grain simulation facility

    NASA Technical Reports Server (NTRS)

    Huntington, J. L.; Schwartz, D. E.; Marshall, J. R.

    1991-01-01

    The Gas-Grain Simulation Facility (GGSF) will provide a microgravity environment where undesirable environmental effects are reduced, and thus, experiments involving interactions between small particles and grains can be more suitably performed. Slated for flight aboard the Shuttle in 1992, the ESA glovebox will serve as a scientific and technological testbed for GGSF exobiology experiments as well as generating some basic scientific data. Initial glovebox experiments will test a method of generating a stable, mono-dispersed cloud of fine particles using a vibrating sprinkler system. In the absence of gravity and atmospheric turbulence, it will be possible to determine the influence of interparticle forces in controlling the rate and mode of aggregation. The experimental chamber can be purged of suspended matter to enable multiple repetitions of the experiments. Of particular interest will be the number of particles per unit volume of the chamber, because it is suspected that aggregation will occur extremely rapidly if the number exceeds a critical value. All aggregation events will be recorded on high-resolution video film. Changes in the experimental procedure as a result of surprise events will be accompanied by real-time interaction with the mission specialist during the Shuttle flight.

  9. Planetary polarization nephelometer

    NASA Astrophysics Data System (ADS)

    Banfield, D.; Dissly, R.; Mishchenko, M.; Muñoz, O.; Roos-Serote, M.; Stam, D.; Volten, H.

    2004-02-01

    We have proposed to develop a polarization nephelometer for use on future planetary descent probes. It will measure both the scattered intensity and polarization phase functions of the aerosols it encounters descending through an atmosphere. These measurements will be taken at two wavelengths separated by about an octave, with one light source near 500nm and another near 1μm. Adding polarization measurements to the intensity phase functions greatly increases our ability to constrain the size distribution, shape and chemical composition of the sampled particles. There remain important questions about these parameters of the aerosols on Venus, the giant planets and Titan that can only be addressed with a nephelometer like ours. The NRC Planetary Sciences Decadal Survey has identified probe missions to Venus and Jupiter as a priority. On both of these missions, our proposed instrument would be an excellent candidate for flight. We also expect that future probe missions to Saturn, Uranus, Neptune or Titan would employ our instrument. It could also find use in Earth in situ aerosol studies. We will use a technique to simultaneously measure intensity and polarization phase functions that uses polarization modulation of a light source. This technique has been implemented in laboratory settings, but not with considerations to the environment on a planetary descent probe. We have proposed to design and build a flexible breadboard nephelometer to test the components and concepts of our approach. We would then test the device against well defined aerosols, ensuring that it accurately measures their expected intensity and polarization phase functions. With the knowledge gained in this flexible design, we would then design and build a breadboard polarization nephelometer more suited to integration on a planetary descent probe. To include traceability in the technical requirements of our device, we would also conduct an Observing System Simulation Experiment. In this study, we

  10. Towards combined modeling of planetary accretion and differentiation

    NASA Astrophysics Data System (ADS)

    Golabek, G. J.; Gerya, T.; Morishima, R.; Tackley, P. J.; Labrosse, S.

    2011-12-01

    Results of current 1D models on planetesimal accretion yield an onion-like thermal structure with very high internal temperatures due to powerful short-lived radiogenic heating in the planetesimals. These lead to extensive silicate melting in the parent bodies. Yet, magma ocean and impact processes are not considered in these models and core formation is, if taken into account, assumed to be instantaneous with no feedback on the mantle evolution. It was pointed out that impacts can not only deposit heat deep into the target body, which is later buried by ejecta of further impacts [1], but also that impacts expose in the crater region originally deep-seated layers, thus cooling the interior [2]. This combination of impact effects becomes even more important when we consider that planetesimals of all masses contribute to planetary accretion. This leads occasionally to collisions between bodies with large ratios between impactor and target mass. Thus, all these processes can be expected to have a profound effect on the thermal evolution during the epoch of planetary accretion and may have implications for the onset of mantle convection and cannot be described properly in 1D geometry. Here we present a new methodology, which can be used to simulate the internal evolution of a planetary body during accretion and differentiation: Using the N-body code PKDGRAV [3] we simulate the accretion of planetary embryos from an initial annulus of several thousand planetesimals. The growth history of the largest resulting planetary embryo is used as an input for the thermomechanical 2D code I2ELVIS [4]. The thermomechanical model takes recent parametrizations of impact processes like impact heating and crater excavation [5] into account. The model also includes both long- and short-lived radiogenic isotopes and a more realistic treatment of largely molten silicates [6]. Results show that late-formed planetesimals do not experience silicate melting and avoid thermal alteration

  11. Towards combined modeling of planetary accretion and differentiation

    NASA Astrophysics Data System (ADS)

    Golabek, G. J.; Gerya, T. V.; Morishima, R.; Tackley, P. J.; Labrosse, S.

    2012-09-01

    accretion yield an onion-like thermal structure with very high internal temperatures due to powerful short-lived radiogenic heating in the planetesimals. These lead to extensive silicate melting in the parent bodies. Yet, magma ocean and impact processes are not considered in these models and core formation is, if taken into account, assumed to be instantaneous with no feedback on the mantle evolution. It was pointed out that impacts can not only deposit heat deep into the target body, which is later buried by ejecta of further impacts [1], but also that impacts expose in the crater region originally deep-seated layers, thus cooling the interior [2]. This combination of impact effects becomes even more important when we consider that planetesimals of all masses contribute to planetary accretion. This leads occasionally to collisions between bodies with large ratios between impactor and target mass. Thus, all these processes can be expected to have a profound effect on the thermal evolution during the epoch of planetary accretion and may have implications for the onset of mantle convection and cannot be described properly in 1D geometry. Here we present a new methodology, which can be used to simulate the internal evolution of a planetary body during accretion and differentiation: Using the N-body code PKDGRAV[3] we simulate the accretion of planetary embryos from an initial annulus of several thousand planetesimals. The growth history of the largest resulting planetary embryo is used as an input for the thermomechanical 2D code I2ELVIS [4]. The thermomechanical model takes recent parametrizations of impact processes like impact heating and crater excavation [5] into account. The model also includes both long- and short-lived radiogenic isotopes and a more realistic treatment of largely molten silicates [6]. Results show that late-formed planetesimals do not experience silicate melting and avoid thermal alteration, whereas in early-formed bodies accretion and iron

  12. Exploring Asteroid Interiors: The Deep Interior Mission Concept

    NASA Technical Reports Server (NTRS)

    Asphaug, E.; Belton, M. J. S.; Cangahuala, A.; Keith, L.; Klaasen, K.; McFadden, L.; Neumann, G.; Ostro, S. J.; Reinert, R.; Safaeinili, A.

    2003-01-01

    Deep Interior is a mission to determine the geophysical properties of near-Earth objects, including the first volumetric image of the interior of an asteroid. Radio reflection tomography will image the 3D distribution of complex dielectric properties within the 1 km rendezvous target and hence map structural, density or compositional variations. Laser altimetry and visible imaging will provide high-resolution surface topography. Smart surface pods culminating in blast experiments, imaged by the high frame rate camera and scanned by lidar, will characterize active mechanical behavior and structure of surface materials, expose unweathered surface for NIR analysis, and may enable some characterization of bulk seismic response. Multiple flybys en route to this target will characterize a diversity of asteroids, probing their interiors with non-tomographic radar reflectance experiments. Deep Interior is a natural follow-up to the NEARShoemaker mission and will provide essential guidance for future in situ asteroid and comet exploration. While our goal is to learn the interior geology of small bodies and how their surfaces behave, the resulting science will enable pragmatic technologies required of hazard mitigation and resource utilization.

  13. Stationary Planetary Waves in the Mars Winter Atmosphere as seen by the Radio Science Experiment MaRS on Mars Express

    NASA Astrophysics Data System (ADS)

    Tellmann, Silvia; Pätzold, Martin; Häusler, Bernd; Tyler, Leonard G.; Hinson, David P.

    2015-11-01

    Stationary (Rossby) Waves are excited by the interaction of the zonally varying topography with the strong eastward winter jets. They lead to distinctive longitudinal temperature variations which contribute significantly to the asymmetry of the seasonal polar CO2 ice caps and are also important for the dust redistribution in the planetary atmosphere.Radio Science profiles from the Mars Express Radio Science Experiment MaRS at northern and southern high latitudes are used to gain insight into winter stationary wave structures on both hemispheres.Mars Global Surveyor (MGS) radio occultation measurements from the same season and year with their exceptionally good longitudinal and temporal coverage can be used to estimate the influence of transient eddies. Transient waves are especially important in the northern winter hemisphere.Wave number 2 stationary waves, driven by topography, are dominant in the northern winter latitudes while the wave number 1 wave is the most significant wave number during southern winter. The wave amplitudes peak around winter solstice on both hemispheres.Radio occultation measurements provide the unique opportunity to determine simultaneous measurements of temperature and geopotential height structures. Assuming geostrophic balance, these measurements can be used to determine meridional winds and eddy heat fluxes which provide further insight into the contribution of stationary waves to the heat exchange between the poles and the lower latitudes.

  14. Planetary evolution and habitability

    NASA Astrophysics Data System (ADS)

    Spohn, T.

    2008-09-01

    Planetary habitability is usually thought to require water on (or near) the surface, a magnetic field to protect life against cosmic radiation, and transport mechanisms for nutrients. A magnetic field also serves to protect an existing atmosphere against erosion by the solar wind and thus helps to stabilize the presence of water and habitability. Magnetic fields are generated in the cores of the terrestrial planets and thus habitability is linked to the evolution of the interior. Moreover, the interior is a potential source and sink for water and CO2 and may interact with the surface and atmosphere reservoirs through volcanic activity and recycling. On the Earth, water is stabilized by complex interactions between the atmosphere, the biosphere, the oceans, the crust, and the deep interior. On geological timescales, the anorganic CO2 cycle is most important. The most efficient known mechanism for recycling is plate tectonics. Plate tectonics is known to operate, at present, only on the Earth, although Mars may have had a phase of plate tectonics as may have Venus. Single-plate tectonics associated with stagnant lid convection can transfer water and CO2 from the interior but a simple recycling mechanism is lacking for this tectonic style. Stagnant lid convection will evolve to thicken the lid and increasingly frustrate volcanic activity and degassing. (This can keep the interior from running completely dry.) Plate tectonics supports the generation of magnetic fields by effectively cooling the deep interior. In addition, plate tectonics rejuvenates nutrients on the surface and generates granitic cratons. For Venus it is likely that a present-day magnetic field would require plate tectonics to operate. The chemistry of the Martian core likely precludes the growth of an inner core and thus a present-day dynamo. An early field is possible for both planets even with stagnant lid convection but the dynamos will have operated less than about a billion years on Mars and a

  15. Resistance of spacecraft isolates to outer space for planetary protection purposes -first results of the experiment PROTECT of the EXPOSE-E mission.

    NASA Astrophysics Data System (ADS)

    Horneck, Gerda; Moeller, Ralf

    Spore-forming microbes are of particular concern in the context of planetary protection, be-cause their endospores are highly resistant to a variety of environmental extremes, including certain sterilization procedures and the harsh environment of outer space or planetary sur-faces (Nicholson et al., 2000; Horneck et al. 2009). Furthermore, isolates from space craft and space craft assembly facilities have been identified that form spores of an elevated resistance to various physical and chemical conditions, such as ionizing and UV radiation, desiccation and oxidative stress (La Duc et al., 2007). This observation led to the supposition that the spe-cial conditions of ultraclean spacecraft assembly facilities and the applied spacecraft cleaning and decontamination measures cause a selection of the most resistant organisms as survivors. To test this hypothesis, spores of B. pumilus SAFR-032 isolated from these environments as well as spores of the laboratory strain B. subtilis 168 were subjected to selected parameters of space in the experiment PROTECT during the EXPOSE-E mission (February 7, 2008 -September 12, 2009), attached to the EuTEF platform outside of the Columbus module of the International Space Station. The spores were mounted as dry layers onto spacecraft-qualified material (aluminum coupons) and exposed to the following parameters of space, applied sep-arately or in selected combinations: (i) space vacuum, (ii) solar extraterrestrial UV radiation including vacuum-UV, (iii) simulated Mars atmosphere and UV radiation climate, and (iv) galactic cosmic radiation. After recovery, visual inspection showed color changes of the sun-exposed spore samples from white to brownish demonstrating photochemical damage caused by solar extraterrestrial UV radiation. On-going analyses include studies of viability and capabil-ity of repair of damage, mutagenic spectrum, e.g. trp-revertants, rifampicin-resistant mutants, DNA lesion, global gene expression, and genomic and

  16. Efficiency study comparing two helicopter planetary reduction stages

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy L.; Handschuh, Robert F.

    1990-01-01

    A study was conducted to compare the efficiency of two helicopter transmission planetary reduction stages. Experimental measurements and analytical predictions were made. The analysis predicted and experiments verified that one planetary stage was a more efficient design due to the type of planet bearing used in the stage. The effects of torque, speed, lubricant type, and lubricant temperature on planetary efficiency are discussed.

  17. Virtual reality and planetary exploration

    NASA Technical Reports Server (NTRS)

    Mcgreevy, Michael W.

    1992-01-01

    NASA-Ames is intensively developing virtual-reality (VR) capabilities that can extend and augment computer-generated and remote spatial environments. VR is envisioned not only as a basis for improving human/machine interactions involved in planetary exploration, but also as a medium for the more widespread sharing of the experience of exploration, thereby broadening the support-base for the lunar and planetary-exploration endeavors. Imagery representative of Mars are being gathered for VR presentation at such terrestrial sites as Antarctica and Death Valley.

  18. Continuing Studies of Planetary Atmospheres Associated with Experiments on the Galileo Jupiter Probe and Infrared Observations of Venus

    NASA Technical Reports Server (NTRS)

    Ragent, Boris

    1998-01-01

    The results of the nephelometer experiment conducted aboard the Probe of the Galileo mission to Jupiter are presented. The tenuous clouds and sparse particulate matter in the relatively particle-free 5-micron "hot spot" region of the Probe's descent were documented from about 0.46 bars to about 12 bars. Three regions of apparent coherent structure were noted, in addition to many indications of extremely small particle concentrations along the descent path. From the first valid measurement at about 0.46 bars down to about 0.55 bars a feeble decaying lower portion of a cloud, corresponding with the predicted ammonia particle cloud, was encountered. A denser, but still very modest, particle structure was present in the pressure regime extending from about 0.76 to a distinctive base at 1.34 bars, and is compatible with the expected ammonium hydrosulfide cloud. No massive water cloud was encountered, although below the second structure, a small, vertically thin layer at about 1.65 bars may be detached from the cloud above, but may also be water condensation, compatible with reported measurements of water abundance from other Galileo Mission experiments. A third small signal region, extending from about 1.9 to 4.5 bars, exhibited quite weak but still distinctive structure, and, although the identification of the light scatterers in this region is uncertain, may also be a water cloud perhaps associated with lateral atmospheric motion and/or reduced to a small mass density by atmospheric subsidence or other explanations. Rough descriptions of the particle size distributions and cloud properties in these regions have been derived, although they may be imprecise because of the small signals and experimental difficulties. These descriptions document the small number densities of particles, the moderate particle sizes, generally in the slightly submicron to few micron range, and the resulting small optical depths, mass densities due to particles, column particle number loading

  19. Continuing Studies of Planetary Atmospheres Associated With Experiments on the Galileo Jupiter Probe and Infrared Observations of Venus

    NASA Technical Reports Server (NTRS)

    Goodman,Jindra; Ragent, Boris

    1998-01-01

    The results of the nephelometer experiment conducted aboard the Probe of the Galileo mission to Jupiter are presented. The tenuous clouds and sparse particulate matter in the relatively particle-free 5-micron "hot spot" region of the Probe's descent were documented from about 0.46 bars to about 12 bars. Three regions of apparent coherent structure were noted, in addition to many indications of extremely small particle concentrations along the descent path. From the first valid measurement at about 0.46 bars down to about 0.55 bars a feeble decaying lower portion of a cloud, corresponding with the predicted ammonia particle cloud, was encountered. A denser, but still very modest, particle structure was present in the pressure regime extending from about 0.76 to a distinctive base at 1.34 bars, and is compatible with the expected ammonium hydrosulfide cloud. No massive water cloud was encountered, although below the second structure, a small, vertically thin layer at about 1.65 bars may be detached from the cloud above, but may also be water condensation, compatible with reported measurements of water abundance from other Galileo Mission experiments. A third small signal region, extending from about 1.9 to 4.5 bars, exhibited quite weak but still distinctive structure, and, although the identification of the light scatterers in this region is uncertain, may also be a water cloud perhaps associated with lateral atmospheric motion and/or reduced to a small mass density by atmospheric subsidence or other explanations. Rough descriptions of the particle size distributions and cloud properties in these regions have been derived, although they may be imprecise because of the small signals and experimental difficulties. These descriptions document the small number densities of particles, the moderate particle sizes, generally in the slightly submicron to few micron range, and the resulting small optical depths, mass densities due to particles, column particle number loading

  20. Using Vulcan to Recreate Planetary Cores

    SciTech Connect

    Collins, G.W.; Celliers, P.M.; Hicks, D.G.; Mackinnon, A.J.; Moon, S.J.; Cauble, R.; DaSilva, L.B.; Koening, M.; Benuzzi-Mounaix, A.; Huser, G.; Jeanloz, R.; Lee, K.M.; Benedetti, L.R.; Henry, E.; Batani, D.; Willi, O.; Pasley, J.; Gessner, H.; Neely, D.; Notley, M.; Danson, C.

    2001-08-15

    An accurate equation of state (EOS) for planetary constituents at extreme conditions is the key to any credible model of planets or low mass stars. However, experimental validation has been carried out on at high pressure (>few Mbar), and then only on the principal Hugoniot. For planetary and stellar interiors, compression occurs from gravitational force so that material states follow a line of isentropic compression (ignoring phase separation) to ultra-high densities. An example of the predicted states for water along the isentrope for Neptune is shown in a figure. The cutaway figure on the left is from Hubbard, and the phase diagram on the right is from Cavazzoni et al. Clearly these states lie at quite a bit lower temperature and higher density than single shock Hugoniot states but they are at higher temperature than can be achieved with accurate diamond anvil experiments. At extreme densities, material states are predicted to have quite unearthly properties such as high temperature superconductivity and low temperature fusion. High density experiments on Earth are achieved with either static compression techniques (i.e.diamond anvil cells) or dynamic compression techniques using large laser facilities, gas guns, or explosives. A major thrust of this work is to develop techniques to create and characterize material states that exists primarily at the core of giant planets and brown dwarf stars. Typically, models used to construct planetary isentropes are constrained by only the planet radius, outer atmospheric spectroscopy, and space probe gravitational moment and magnetic field data. Thus any data, which provide rigid constraints for these models will have a significant impact on a broad community of planetary and condensed matter scientists. Recent laser shock wave experiments have made great strides in recreating material states that exist in the outer 25% (in radius) of the Jovian planets and at the exterior of low-mass stars. Large laser facilities have

  1. Short-Term Research Experiences with Teachers in Earth and Planetary Sciences and a Model for Integrating Research into Classroom Inquiry

    NASA Astrophysics Data System (ADS)

    Morgan, P.; Bloom, J. W.

    2006-12-01

    For the past three summers, we have worked with in-service teachers on image processing, planetary geology, and earthquake and volcano content modules using inquiry methods that ended with mini-research experiences. Although almost all were science teachers, very few could give a reasonable definition of science at the start of the modules, and very few had a basic grasp of the processes of scientific research and could not include substantive scientific inquiry into their lessons. To build research understanding and confidence, an instructor-student interaction model was used in the modules. Studies have shown that children who participate in classrooms as learning and inquiry communities develop more complex understandings. The same patterns of complex understandings have resulted in similarly structured professional communities of teachers. The model is based on professional communities, emphasizing from the beginning that inquiry is a form of research. Although the actual "research" component of the modules was short, the teachers were identified as professionals and researchers from the start. Research/inquiry participation is therefore an excellent example by which to allow their teachers to learn. Initially the teachers were very reluctant to pose questions. As they were encouraged to share, collaborate, and support each other, the role of the instructor became less of a leader and more of a facilitator, and the confidence of the teachers as professionals and researchers grew. One teacher even remarked, "This is how we should be teaching our kids!' Towards the end of the modules the teachers were ready for their mini- research projects and collaborated in teams of 2-4. They selected their own research topics, but were guided toward research questions that required data collection (from existing studies), some data manipulation, interpretation, and drawing conclusions with respect to the original question. The teachers were enthusiastic about all of their

  2. Effects of simulated space radiation on immunoassay components for life-detection experiments in planetary exploration missions.

    PubMed

    Derveni, Mariliza; Hands, Alex; Allen, Marjorie; Sims, Mark R; Cullen, David C

    2012-08-01

    The Life Marker Chip (LMC) instrument is part of the proposed payload on the ESA ExoMars rover that is scheduled for launch in 2018. The LMC will use antibody-based assays to detect molecular signatures of life in samples obtained from the shallow subsurface of Mars. For the LMC antibodies, the ability to resist inactivation due to space particle radiation (both in transit and on the surface of Mars) will therefore be a prerequisite. The proton and neutron components of the mission radiation environment are those that are expected to have the dominant effect on the operation of the LMC. Modeling of the radiation environment for a mission to Mars led to the calculation of nominal mission fluences for proton and neutron radiation. Various combinations and multiples of these values were used to demonstrate the effects of radiation on antibody activity, primarily at the radiation levels envisaged for the ExoMars mission as well as at much higher levels. Five antibodies were freeze-dried in a variety of protective molecular matrices and were exposed to various radiation conditions generated at a cyclotron facility. After exposure, the antibodies' ability to bind to their respective antigens was assessed and found to be unaffected by ExoMars mission level radiation doses. These experiments indicated that the expected radiation environment of a Mars mission does not pose a significant risk to antibodies packaged in the form anticipated for the LMC instrument. PMID:22897155

  3. Planetary science

    NASA Technical Reports Server (NTRS)

    Marshall, John R.; Bridges, Frank; Gault, Donald; Greeley, Ronald; Houpis, Harry; Lin, Douglas; Weidenschilling, Stuart

    1987-01-01

    The following types of experiments for a proposed Space Station Microgravity Particle Research Facility are described: (1) low velocity collisions between fragile particles; (2) low velocity collisions of ice particles; (3) plasma-dust interaction; and (4) aggregation of finely-comminuted geological materials. The required capabilities and desired hardware for the facility are detailed.

  4. SinoProbe-02: Integrated experiment of deep-exploring techniques to reveal the interior structure beneath the Chinese continent (Invited)

    NASA Astrophysics Data System (ADS)

    Gao, R.; Lu, Z.; Wang, H.; Li, W.; Zeng, L.

    2010-12-01

    SinoProbe is a new five year program (2008-2012) funded by the Chinese government. Its primary objectives are (1) to explore the interior structure and geodynamic processes beneath the Chinese continent, (2) to reveal the tectonic evolution of continent, and (3) to provide new scientific data and information for the exploration of new resources at depth. SinoProbe-02 is one of the key projects essential for fulfilling the primary objectives of SinoProbe. In this project, we will apply techniques including deep seismic reflection profiling (CMP), deep seismic sounding (DSS), broadband seismic observation (BB), magnetotelluric sounding (MT), and other methods to determine the physical properties and in turn to image the structure and composition of the crust and mantle of the Chinese continent. In conjunction with high resolution geologic field mapping and observation, these data will be integrated to extend the near surface structures down to significant deeper levels, to address the key mechanisms for the deformation of the crust at different levels, to provide scientific information for exploration of energy and mineral resources at depth, to tackle important problems of the tectonic evolution of continental crust and mantle, and finally to shed new insights on the mechanisms for large earthquake, volcanism, and other catastrophic events. To achieve the major objectives of the SinoProbe-2, experiments with different techniques will be deployed along four major cross-section lines that traverse key orogenic belts and sedimentary basins. These include the Himalaya-Karakoram-Tibet (HKT) profile, South China Profile (SCP), North China Profile (NCP), and Northeast China Profile (NECP), respectively. By the end of year 2010, our team has completed ~1900 km long seismic experiments which include 300 km of HKT, 500 km of SCP, 500 km of NCP, and 600 km of NECP, respectively. These new data reveal several important features of the structure of continental lithosphere. In

  5. Analysis of science team activities during the 1999 Marsokhod Rover Field Experiment: Implications for automated planetary surface exploration

    NASA Astrophysics Data System (ADS)

    Thomas, Geb; Cabrol, Nathalie; Rathe, April

    2001-04-01

    This work analyzes the behavior and effectiveness of a science team using the Marsokhod mobile robot to explore the Silver Lake region in the Mojave Desert near Baker, California. The work addresses the manner in which the geologists organized themselves, how they allocated their time in different activities, how they formed and communicated scientific hypotheses, and the frequency with which they requested different types of data from the mission archive during the first 3 days of the mission. Eleven scientists from the NASA Ames Research Center and three of the five scientists who participated from their home institutions were videotaped as they worked throughout the 3-day experiment. The videotape record indicates that 46% of available person-hours were consumed in semistructured or formal meetings and that only 1% of their time was spent studying immersive, three-dimensional virtual reality models of the robot's surroundings. The remainder of their time was spent in unstructured work sessions in groups of two or three. Hypothesis formation and evolution patterns show a meager flow of information from the distributed science team to the on-site team and a bias against reporting speculative hypotheses. Analysis of the visual imagery received from the robot indicates that acquisition of the large panoramic information leads to high levels of redundancy in the data acquired. The scientists' archive requests indicate that small, specifically requested image targets were the most frequently accessed information. The work suggests alternative organizational structures that would expedite the flow of information within the geologic team. It also advocates emphasizing specific science targets over high-resolution, stereoscopic, panoramic imaging when programming a mobile robot's onboard cameras.

  6. Smart Ultrasound Remote Guidance Experiment (SURGE)- Concept of Operations Evaluation for Using Remote Guidance Ultrasound for Planetary Space Flight

    NASA Technical Reports Server (NTRS)

    Hurst, Victor, IV; Peterson, Sean; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

    2010-01-01

    Introduction Use of remote guidance (RG) techniques aboard the International Space Station (ISS) has enabled astronauts to collect diagnostic-level ultrasound images. Exploration class missions will require this cohort of (typically) non-formally trained sonographers to operate with greater autonomy given the longer communication delays (2 seconds for ISS vs. >6 seconds for missions beyond the Moon) and communication blackouts. To determine the feasibility and training requirements for autonomous ultrasound image collection by non-expert ultrasound operators, ultrasound images were collected from a similar cohort using three different image collection protocols: RG only, RG with a computer-based learning tool (LT), and autonomous image collection with LT. The groups were assessed for both image quality and time to collect the images. Methods Subjects were randomized into three groups: RG only, RG with LT, and autonomous with LT. Each subject received 10 minutes of standardized training before the experiment. The subjects were tasked with making the following ultrasound assessments: 1) bone fracture and 2) focused assessment with sonography in trauma (FAST) to assess a patient s abdomen. Human factors-related questionnaire data were collected immediately after the assessments. Results The autonomous group did not out-perform the two groups that received RG. The mean time for the autonomous group to collect images was less than the RG groups, however the mean image quality for the autonomous group was less compared to both RG groups. Discussion Remote guidance continues to produce higher quality ultrasound images than autonomous ultrasound operation. This is likely due to near-instant feedback on image quality from the remote guider. Expansion in communication time delays, however, diminishes the capability to provide this feedback, thus requiring more autonomous ultrasound operation. The LT has the potential to be an excellent training and coaching component for

  7. Carbon substitution for oxygen in silicates in planetary interiors

    PubMed Central

    Sen, Sabyasachi; Widgeon, Scarlett J.; Navrotsky, Alexandra; Mera, Gabriela; Tavakoli, Amir; Ionescu, Emanuel; Riedel, Ralf

    2013-01-01

    Amorphous silicon oxycarbide polymer-derived ceramics (PDCs), synthesized from organometallic precursors, contain carbon- and silica-rich nanodomains, the latter with extensive substitution of carbon for oxygen, linking Si-centered SiOxC4-x tetrahedra. Calorimetric studies demonstrated these PDCs to be thermodynamically more stable than a mixture of SiO2, C, and silicon carbide. Here, we show by multinuclear NMR spectroscopy that substitution of C for O is also attained in PDCs with depolymerized silica-rich domains containing lithium, associated with SiOxC4-x tetrahedra with nonbridging oxygen. We suggest that significant (several percent) substitution of C for O could occur in more complex geological silicate melts/glasses in contact with graphite at moderate pressure and high temperature and may be thermodynamically far more accessible than C for Si substitution. Carbon incorporation will change the local structure and may affect physical properties, such as viscosity. Analogous carbon substitution at grain boundaries, at defect sites, or as equilibrium states in nominally acarbonaceous crystalline silicates, even if present at levels at 10–100 ppm, might form an extensive and hitherto hidden reservoir of carbon in the lower crust and mantle. PMID:24043830

  8. Carbon substitution for oxygen in silicates in planetary interiors.

    PubMed

    Sen, Sabyasachi; Widgeon, Scarlett J; Navrotsky, Alexandra; Mera, Gabriela; Tavakoli, Amir; Ionescu, Emanuel; Riedel, Ralf

    2013-10-01

    Amorphous silicon oxycarbide polymer-derived ceramics (PDCs), synthesized from organometallic precursors, contain carbon- and silica-rich nanodomains, the latter with extensive substitution of carbon for oxygen, linking Si-centered SiO(x)C(4-x) tetrahedra. Calorimetric studies demonstrated these PDCs to be thermodynamically more stable than a mixture of SiO2, C, and silicon carbide. Here, we show by multinuclear NMR spectroscopy that substitution of C for O is also attained in PDCs with depolymerized silica-rich domains containing lithium, associated with SiO(x)C(4-x) tetrahedra with nonbridging oxygen. We suggest that significant (several percent) substitution of C for O could occur in more complex geological silicate melts/glasses in contact with graphite at moderate pressure and high temperature and may be thermodynamically far more accessible than C for Si substitution. Carbon incorporation will change the local structure and may affect physical properties, such as viscosity. Analogous carbon substitution at grain boundaries, at defect sites, or as equilibrium states in nominally acarbonaceous crystalline silicates, even if present at levels at 10-100 ppm, might form an extensive and hitherto hidden reservoir of carbon in the lower crust and mantle. PMID:24043830

  9. Planetary magnetism and the interiors of the moon and Mercury

    NASA Technical Reports Server (NTRS)

    Cassen, P.

    1977-01-01

    Various theories regarding lunar and Mercurian magnetic properties are discussed in terms of the thermal evolutions of these bodies. In particular, the extinct dynamo, the primordial field of external origin, local mechanisms, and the active dynamo hypotheses are reviewed. The theory involving magnetization by an internal dynamo is applied to Mercury, noting that it implies the existence of a molten metallic core, or shell. Possible sources of the energy required for core differentiation are discussed, including accretional heating, long-lived radioactive isotopes, and other radioactive heat sources. Thermal processes which might keep the core molten are suggested along with processes permitting the flow of heat through the mantle. Conclusions suggested by the dynamo hypothesis are reviewed in terms of current models of the thermal evolution of Mercury and the moon.

  10. Fluid helium at conditions of giant planetary interiors

    PubMed Central

    Stixrude, Lars; Jeanloz, Raymond

    2008-01-01

    As the second most-abundant chemical element in the universe, helium makes up a large fraction of giant gaseous planets, including Jupiter, Saturn, and most extrasolar planets discovered to date. Using first-principles molecular dynamics simulations, we find that fluid helium undergoes temperature-induced metallization at high pressures. The electronic energy gap (band gap) closes at 20,000 K at a density half that of zero-temperature metallization, resulting in electrical conductivities greater than the minimum metallic value. Gap closure is achieved by a broadening of the valence band via increased s–p hydridization with increasing temperature, and this influences the equation of state: The Grüneisen parameter, which determines the adiabatic temperature–depth gradient inside a planet, changes only modestly, decreasing with compression up to the high-temperature metallization and then increasing upon further compression. The change in electronic structure of He at elevated pressures and temperatures has important implications for the miscibility of helium in hydrogen and for understanding the thermal histories of giant planets.

  11. Advances in planetary geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (Editor)

    1981-01-01

    This second issue in a new series intended to serve the planetary geology community with a form for quick and thorough communications includes (1) a catalog of terrestrial craterform structures for northern Europe; (2) abstracts of results of the Planetary Geology Program, and (3) a list of the photographic holdings of regional planetary image facilities.

  12. Planetary radar astronomy

    NASA Astrophysics Data System (ADS)

    Ostro, S. J.

    1983-03-01

    The present investigation is concerned with planetary radar research reported during the time from 1979 to 1982. A brief synopsis of radar definitions and technical terminology is also provided. In connection with the proximity of the moon to earth, lunar radar studies have been performed over a wider range of wavelengths than radar investigations of other planetary targets. The most recent study of lunar quasispecular scattering is due to Simpson and Tyler (1982). The latest efforts to interpret the lunar radar maps focus on maria-highlands regolith differences and models of crater ejecta evolution. The highly successful Pioneer Venus Radar Mapper experiment has provided a first look at Venus' global distributions of topography, lambda 17-cm radar reflectivity, and rms surface slopes. Attention is given to recent comparisons of Viking Orbiter images of Mars to groundbased radar altimetry of the planet, the icy Galilean satellites, radar observations of asteroids and comets, and lambda 4-cm and lambda 13-cm observations of Saturn's rings.

  13. Phase Equilibrium Investigations of Planetary Materials

    NASA Technical Reports Server (NTRS)

    Grove, T. L.

    1997-01-01

    This grant provided funds to carry out experimental studies designed to illuminate the conditions of melting and chemical differentiation that has occurred in planetary interiors. Studies focused on the conditions of mare basalt generation in the moon's interior and on processes that led to core formation in the Shergottite Parent Body (Mars). Studies also examined physical processes that could lead to the segregation of metal-rich sulfide melts in an olivine-rich solid matrix. The major results of each paper are discussed below and copies of the papers are attached as Appendix I.

  14. Interior of Mars from InSight geodesy

    NASA Astrophysics Data System (ADS)

    Dehant, V.; Folkner, W.; Asmar, S.; Rivoldini, A.; Van Hoolst, T.; Banerdt, B.

    2012-04-01

    Within the INSIGHT mission, the radioscience experiment aims at obtaining the rotation and interior structure of Mars. It is called for that reason RISE (Rotation and Interior Structure Experiment). It does not uses an instrument stricto sensus but uses the spacecraft X-band communication system. The parameters that will be determined from the rotation and orientation observation (i.e. from length-of-day variations, precession (long-term changes in the rotational orientation), and nutations (periodic changes in the rotational orientation)) are the angular momentum of the atmosphere, the moments of inertia of the whole planet and of the core. This will allow to constrain the interior models of Mars. The Doppler effect on the radio signal is related to the variations of the rotation and orientation of the planet Mars. When measured for a time longer than the seasonal timescale, the observation can provide values for the moments of inertia. The mean moment of inertia is a strong constraint on the core size and density, core temperature and mantle mineralogy. The size of the core has major consequences for internal structure and planetary evolution. For example, a large core makes a perovskite-bearing lower mantle impossible, due to insufficient pressure at the base of the mantle. The endothermic phase transition spinel-perovskite has a strong effect on mantle convection. The size and composition of the core are also important in the history of the magnetic dynamo, which in turn has important consequences for the retention of the atmosphere and the possible habitability of the surface early in Mars' history.

  15. A Discovery Mission to Determine the Interior Structure of Gas- and Ice-Giants

    NASA Astrophysics Data System (ADS)

    Hofstadter, Mark D.; Murphy, N.; Matousek, S.; Bairstow, S.; Maiwald, F.; Jeffries, S.; Schmider, F.; Guillot, T.

    2013-10-01

    The Ice Giants (Uranus and Neptune) are fundamentally different than the better-known Gas Giants (Jupiter and Saturn). Ice Giants are roughly 65% water by mass, compared to Gas Giants which are ~95% hydrogen and helium. Knowing the interior structure of both types of planets is a key measurement needed to advance our understanding of the formation and evolution of planetary systems, particularly in light of recent findings that Ice Giants are far more abundant in our galaxy than Gas Giants (Borucki et al., ApJ 2011). In the past, gravity measurements from spacecraft in low orbits have been the primary way to tease out information on interior structure. A new approach, Doppler imaging, can provide detailed information on interior structure from great distances (Gaulme et al., A&A 2011). A planetary Doppler Imager (DI) builds on the well-established fields of helio- and stellar-seismology, which have revolutionized our understanding of the interior of stars. The great advantage of a DI is that its observations do not require the spacecraft to enter orbit. We have designed a Discovery mission around such an instrument to determine the interior structures of Jupiter and Uranus during flybys of each planet. The data collected at Jupiter (after a 1.5 year flight) will compliment observations to be made by the Juno spacecraft in 2016, creating a much more accurate picture of the interior than is possible from the gravity technique alone. Roughly 6.5 years after the Jupiter flyby, DI measurements of Uranus will open that planet's interior for the first time. At both planets, measurements of the interior structure are made over a 4-month period centered on closest approach (CA), but with a ~1 week gap at CA when the planet is too close for whole-disk imaging. This allows other measurements to be made at that time, such as of small-scale weather features or satellites. We note that the DI technique, while enabling a Discovery-class mission, can also benefit larger missions

  16. New Frontiers at the Intersection of Shock Physics and Planetary Sciences

    NASA Astrophysics Data System (ADS)

    Stewart, Sarah T.

    2011-06-01

    The field of planetary science has exploded with the discovery of over 500 confirmed extrasolar planets and many more candidate planets, almost all larger than Earth. The physical characteristics of extrasolar planetary systems and individual planets differ significantly from our Solar System, leading to fundamentally new ideas about the physics of planetary accretion and the internal structure and evolution of planetary bodies. Understanding the greatly expanded pressure-temperature space of observed planets presents an exciting opportunity and challenge to the high-pressure research community. I illustrate these opportunities with a discussion of recent work on the physics of giant planetary collisions and the internal structures of large rocky bodies called Super-Earths. The terminal collision defining the end of accretion leaves an indelible mark on the final physical and dynamical properties of a rocky planet. For example, in the Solar System, giant collisions are invoked to explain the observed variations in bulk compositions, spin orientations, and satellite systems; in extrasolar systems, recent giant impacts have left behind telltale trails of dust and gas. Using Mbar shock and release experiments, my colleagues and I have measured the liquid-vapor curve of silica. Similar measurements are needed on other important geologic phases to determine the mass of shock-produced vapor during impact events and to develop multiphase equation of state models. Recent work on modeling giant impacts has focused primarily on the dynamics in order to investigate the hypothesized impacts that formed the Moon and stripped Mercury of its silicate mantle. Testing these hypotheses and generalizing our understanding of planet formation requires major advances in equation of state and rheological models. Planetary collisions and interiors provide a unifying area of study for many disciplines within the high-pressure community, including equations of state, strength and fracture

  17. Orbits and Interiors of Planets

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin

    2012-05-01

    The focus of this thesis is a collection of problems of timely interest in orbital dynamics and interior structure of planetary bodies. The first three chapters are dedicated to understanding the interior structure of close-in, gaseous extrasolar planets (hot Jupiters). In order to resolve a long-standing problem of anomalously large hot Jupiter radii, we proposed a novel magnetohydrodynamic mechanism responsible for inflation. The mechanism relies on the electro-magnetic interactions between fast atmospheric flows and the planetary magnetic field in a thermally ionized atmosphere, to induce electrical currents that flow throughout the planet. The resulting Ohmic dissipation acts to maintain the interior entropies, and by extension the radii of hot Jupiters at an enhanced level. Using self-consistent calculations of thermal evolution of hot Jupiters under Ohmic dissipation, we demonstrated a clear tendency towards inflated radii for effective temperatures that give rise to significant ionization of K and Na in the atmosphere, a trend fully consistent with the observational data. Furthermore, we found that in absence of massive cores, low-mass hot Jupiters can over-flow their Roche-lobes and evaporate on Gyr time-scales, possibly leaving behind small rocky cores. Chapters four through six focus on the improvement and implications of a model for orbital evolution of the solar system, driven by dynamical instability (termed the "Nice" model). Hydrodynamical studies of the orbital evolution of planets embedded in protoplanetary disks suggest that giant planets have a tendency to assemble into multi-resonant configurations. Following this argument, we used analytical methods as well as self-consistent numerical N-body simulations to identify fully-resonant primordial states of the outer solar system, whose dynamical evolutions give rise to orbital architectures that resemble the current solar system. We found a total of only eight such initial conditions, providing

  18. Interior Design Students Perceptions of Sustainability

    ERIC Educational Resources Information Center

    Stark, Johnnie; Park, Jin Gyu

    2016-01-01

    Purpose: This longitudinal study assessed student perceptions of sustainable design issues in the context of an accredited interior design program. Although literature exists documenting the integration of sustainable strategies into interior design curriculum, more analysis is needed to determine the impact of program experiences on students'…

  19. Interior intrusion detection systems

    SciTech Connect

    Rodriguez, J.R.; Matter, J.C. ); Dry, B. )

    1991-10-01

    The purpose of this NUREG is to present technical information that should be useful to NRC licensees in designing interior intrusion detection systems. Interior intrusion sensors are discussed according to their primary application: boundary-penetration detection, volumetric detection, and point protection. Information necessary for implementation of an effective interior intrusion detection system is presented, including principles of operation, performance characteristics and guidelines for design, procurement, installation, testing, and maintenance. A glossary of sensor data terms is included. 36 figs., 6 tabs.

  20. HUBBLE'S PLANETARY NEBULA GALLERY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [Top left] - IC 3568 lies in the constellation Camelopardalis at a distance of about 9,000 light-years, and has a diameter of about 0.4 light-years (or about 800 times the diameter of our solar system). It is an example of a round planetary nebula. Note the bright inner shell and fainter, smooth, circular outer envelope. Credits: Howard Bond (Space Telescope Science Institute), Robin Ciardullo (Pennsylvania State University) and NASA [Top center] - NGC 6826's eye-like appearance is marred by two sets of blood-red 'fliers' that lie horizontally across the image. The surrounding faint green 'white' of the eye is believed to be gas that made up almost half of the star's mass for most of its life. The hot remnant star (in the center of the green oval) drives a fast wind into older material, forming a hot interior bubble which pushes the older gas ahead of it to form a bright rim. (The star is one of the brightest stars in any planetary.) NGC 6826 is 2,200 light- years away in the constellation Cygnus. The Hubble telescope observation was taken Jan. 27, 1996 with the Wide Field and Planetary Camera 2. Credits: Bruce Balick (University of Washington), Jason Alexander (University of Washington), Arsen Hajian (U.S. Naval Observatory), Yervant Terzian (Cornell University), Mario Perinotto (University of Florence, Italy), Patrizio Patriarchi (Arcetri Observatory, Italy) and NASA [Top right ] - NGC 3918 is in the constellation Centaurus and is about 3,000 light-years from us. Its diameter is about 0.3 light-year. It shows a roughly spherical outer envelope but an elongated inner balloon inflated by a fast wind from the hot central star, which is starting to break out of the spherical envelope at the top and bottom of the image. Credits: Howard Bond (Space Telescope Science Institute), Robin Ciardullo (Pennsylvania State University) and NASA [Bottom left] - Hubble 5 is a striking example of a 'butterfly' or bipolar (two-lobed) nebula. The heat generated by fast winds causes

  1. Optically measuring interior cavities

    DOEpatents

    Stone, Gary Franklin

    2009-11-03

    A method of measuring the three-dimensional volume or perimeter shape of an interior cavity includes the steps of collecting a first optical slice of data that represents a partial volume or perimeter shape of the interior cavity, collecting additional optical slices of data that represents a partial volume or perimeter shape of the interior cavity, and combining the first optical slice of data and the additional optical slices of data to calculate of the three-dimensional volume or perimeter shape of the interior cavity.

  2. Optically measuring interior cavities

    DOEpatents

    Stone, Gary Franklin

    2008-12-21

    A method of measuring the three-dimensional volume or perimeter shape of an interior cavity includes the steps of collecting a first optical slice of data that represents a partial volume or perimeter shape of the interior cavity, collecting additional optical slices of data that represents a partial volume or perimeter shape of the interior cavity, and combining the first optical slice of data and the additional optical slices of data to calculate of the three-dimensional volume or perimeter shape of the interior cavity.

  3. Rheology of planetary ices

    SciTech Connect

    Durham, W.B.; Kirby, S.H.; Stern, L.A.

    1996-04-24

    The brittle and ductile rheology of ices of water, ammonia, methane, and other volatiles, in combination with rock particles and each other, have a primary influence of the evolution and ongoing tectonics of icy moons of the outer solar system. Laboratory experiments help constrain the rheology of solar system ices. Standard experimental techniques can be used because the physical conditions under which most solar system ices exist are within reach of conventional rock mechanics testing machines, adapted to the low subsolidus temperatures of the materials in question. The purpose of this review is to summarize the results of a decade-long experimental deformation program and to provide some background in deformation physics in order to lend some appreciation to the application of these measurements to the planetary setting.

  4. Significant achievements in the Planetary Geology Program. [geologic processes, comparative planetology, and solar system evolution

    NASA Technical Reports Server (NTRS)

    Head, J. W. (Editor)

    1978-01-01

    Developments reported at a meeting of principal investigators for NASA's planetology geology program are summarized. Topics covered include: constraints on solar system formation; asteriods, comets, and satellites; constraints on planetary interiors; volatiles and regoliths; instrument development techniques; planetary cartography; geological and geochemical constraints on planetary evolution; fluvial processes and channel formation; volcanic processes; Eolian processes; radar studies of planetary surfaces; cratering as a process, landform, and dating method; and the Tharsis region of Mars. Activities at a planetary geology field conference on Eolian processes are reported and techniques recommended for the presentation and analysis of crater size-frequency data are included.

  5. Virtual reality and planetary exploration

    NASA Technical Reports Server (NTRS)

    Mcgreevy, Michael W.

    1992-01-01

    Exploring planetary environments is central to NASA's missions and goals. A new computing technology called Virtual Reality has much to offer in support of planetary exploration. This technology augments and extends human presence within computer-generated and remote spatial environments. Historically, NASA has been a leader in many of the fundamental concepts and technologies that comprise Virtual Reality. Indeed, Ames Research Center has a central role in the development of this rapidly emerging approach to using computers. This ground breaking work has inspired researchers in academia, industry, and the military. Further, NASA's leadership in this technology has spun off new businesses, has caught the attention of the international business community, and has generated several years of positive international media coverage. In the future, Virtual Reality technology will enable greatly improved human-machine interactions for more productive planetary surface exploration. Perhaps more importantly, Virtual Reality technology will democratize the experience of planetary exploration and thereby broaden understanding of, and support for, this historic enterprise.

  6. Interior structure of Neptune - Comparison with Uranus

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.; Nellis, W. J.; Mitchell, A. C.; Holmes, N. C.; Mccandless, P. C.; Limaye, S. S.

    1991-01-01

    Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-called planetary 'ice', have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

  7. Interior structure of Neptune: Comparison with Uranus

    SciTech Connect

    Hubbard, W.B. ); Nellis, W.J.; Mitchell, A.C.; Holmes, N.C.; McCandless, P.C. ); Limaye, S.S. )

    1991-08-09

    Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-called planetary ice, have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

  8. Dynamical Measurements of the Interior Structure of Exoplanets

    NASA Astrophysics Data System (ADS)

    Becker, Juliette; Batygin, K.

    2013-10-01

    Giant gaseous planets often reside on orbits in sufficient proximity to their host stars for the planetary quadrupole gravitational field to become non-negligible. In presence of an additional planetary companion, a precise characterization of the system’s orbital state can yield meaningful constraints on the transiting planet’s interior structure. However, the applicability of this type of analysis can be limited by the configuration of the target system. Here, we explore the dynamical range in which these methods are valid while using HAT-P-13 as a case study. We determine that the interior structure determination method, despite being indirect, is surprisingly robust. As a result, we conclude that future efforts aimed at characterizing the interiors of giant exoplanets are likely to be fruitful.

  9. Advanced planetary studies

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Results of planetary advanced studies and planning support provided by Science Applications, Inc. staff members to Earth and Planetary Exploration Division, OSSA/NASA, for the period 1 February 1981 to 30 April 1982 are summarized. The scope of analyses includes cost estimation, planetary missions performance, solar system exploration committee support, Mars program planning, Galilean satellite mission concepts, and advanced propulsion data base. The work covers 80 man-months of research. Study reports and related publications are included in a bibliography section.

  10. The planetary data system

    NASA Technical Reports Server (NTRS)

    Lee, Steven W.

    1991-01-01

    Nasa has sponsored the development of the Planetary Data System (PDS) in order to preserve the scientific returns from past and future planeary missions and to make those data readily accessible in a well-documented form. The PDS encompasses all planetary data, but also provides a distributed, discipline-oriented architecture to best serve the needs of the diverse planetary sciences user-community. It is the intention of the PDS to ease and promote the analysis of planetary data through the development and application of data and documentation standards, basic analysis tools, and technology.

  11. Planetary geosciences, 1988

    NASA Technical Reports Server (NTRS)

    Zuber, Maria T. (Editor); Plescia, Jeff L. (Editor); James, Odette B. (Editor); Macpherson, Glenn (Editor)

    1989-01-01

    Research topics within the NASA Planetary Geosciences Program are presented. Activity in the fields of planetary geology, geophysics, materials, and geochemistry is covered. The investigator's current research efforts, the importance of that work in understanding a particular planetary geoscience problem, the context of that research, and the broader planetary geoscience effort is described. As an example, theoretical modelling of the stability of water ice within the Martian regolith, the applicability of that work to understanding Martian volatiles in general, and the geologic history of Mars is discussed.

  12. Europa Clipper Mission Concept Preliminary Planetary Protection Approach

    NASA Astrophysics Data System (ADS)

    Jones, Melissa; Schubert, Wayne; Newlin, Laura; Cooper, Moogega; Chen, Fei; Kazarians, Gayane; Ellyin, Raymond; Vaishampayan, Parag; Crum, Ray

    2016-07-01

    The science objectives of the proposed Europa Clipper mission consist of remotely characterizing any water within and beneath Europa's ice shell, investigating the chemistry of the surface and ocean, and evaluating geological processes that may permit Europa's ocean to possess the chemical energy necessary for life. The selected payload supporting the science objectives includes: Plasma Instrument for Magnetic Sounding (PIMS), Interior Characterization of Europa using Magnetometry (ICEMAG), Mapping Imaging Spectrometer for Europa (MISE), Europa Imaging System (EIS), Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON), Europa Thermal Emission Imaging System (E-THEMIS), MAss SPectrometer for Planetary EXploration/Europa (MASPEX), Ultraviolet Spectrograph/Europa (UVS), and SUrface DUst Mass Analyzer (SUDA). Launch is currently baselined as 2022. Pending the yet to be selected launch vehicle, the spacecraft would either arrive to the Jovian system on a direct trajectory in 2025 or an Earth-Venus-Earth-Earth gravity assist interplanetary trajectory arriving in 2030. The operational concept consists of multiple low-altitude flybys of Europa to obtain globally distributed regional coverage of the Europan surface. According to COSPAR Policy, it is currently anticipated that the Europa Clipper mission would be classified as a Category III mission. That is, the mission is to a body "of significant interest relative to the process of chemical evolution and/or the origin of life or for which scientific opinion provides a significant chance of contamination which could jeopardize a future biological experiment." Therefore, the expected driving planetary protection requirement for the mission is that the probability of inadvertent contamination of an ocean or other liquid water body shall be less than 1x10-4 per mission. This requirement applies until final disposition of the spacecraft, however in practice, would only apply until the spacecraft is

  13. Phase Diagrams of Iron Rich Alloys and Their Influence on the Chemical Structure of Planetary Cores

    NASA Astrophysics Data System (ADS)

    Campbell, A. J.; Miller, N. A.; Fischer, R. A.; Seagle, C. T.; Prakapenka, V. B.

    2008-12-01

    Many planetary bodies are thought to have metallic, iron rich cores, with a significant component of some 'light' alloying element(s). The identity of this light alloying component has a profound effect on the chemical properties of the core, including its melting/crystallization behavior, partitioning of minor and trace elements during core/mantle segregation and core crystallization, and other phase relations. Despite this importance, the light element component(s) of planetary bodies generally remain unknown, apart from those of a few iron meteorite parent bodies. Experimentally determined physical and chemical properties of iron-rich systems can be compared to observations and models of planetary interiors to constrain compositions of planetary cores. Here we summarize our recent high pressure, high temperature experiments on the phase diagrams of iron+light element (Fe-X) binaries, specifically iron-sulfide, iron-silicide, and iron-oxide systems. Melting as well as subsolidus phase relations have been determined in the laser heated diamond anvil cell, using either synchrotron X-ray diffraction or optical methods to establish phase boundaries. X-ray diffraction while laser heating the sample reveals the nature of structural transitions (including partial melting), and optical methods (such as temperature vs. emissivity and related methods) establish the phase boundaries with finer precision. Drawing on these and other recent experimental results, we compare and contrast the binary Fe-X phase diagrams to address such questions as: Which candidate light elements (S, Si, O, C) cause the largest melting point depression, and how does this change with pressure? Which can produce large density constrasts against crystallizing iron metal? and others. These results are compared to thermal and chemical models of terrestrial planet interiors (including Earth's), and important gaps and discrepancies in the available experimental data are highlighted.

  14. Planetary geology in the 1980s

    NASA Technical Reports Server (NTRS)

    Veverka, J.

    1984-01-01

    The geologic aspects of solar system studies are defined and the goals of planetary geology are discussed. Planetary geology is the study of the origin, evolution, and distribution of matter condensed in the form of planets, satellites, asteroids, and comets. It is a multidisciplinary effort involving investigators with backgrounds in geology, chemistry, physics, astronomy, geodesy, cartography, and other disciplines concerned with the solid planets. The report is primarily restricted to the kinds of experiments and observations made through unmanned missions.

  15. Planetary heat flow measurements.

    PubMed

    Hagermann, Axel

    2005-12-15

    The year 2005 marks the 35th anniversary of the Apollo 13 mission, probably the most successful failure in the history of manned spaceflight. Naturally, Apollo 13's scientific payload is far less known than the spectacular accident and subsequent rescue of its crew. Among other instruments, it carried the first instrument designed to measure the flux of heat on a planetary body other than Earth. The year 2005 also should have marked the launch of the Japanese LUNAR-A mission, and ESA's Rosetta mission is slowly approaching comet Churyumov-Gerasimenko. Both missions carry penetrators to study the heat flow from their target bodies. What is so interesting about planetary heat flow? What can we learn from it and how do we measure it?Not only the Sun, but all planets in the Solar System are essentially heat engines. Various heat sources or heat reservoirs drive intrinsic and surface processes, causing 'dead balls of rock, ice or gas' to evolve dynamically over time, driving convection that powers tectonic processes and spawns magnetic fields. The heat flow constrains models of the thermal evolution of a planet and also its composition because it provides an upper limit for the bulk abundance of radioactive elements. On Earth, the global variation of heat flow also reflects the tectonic activity: heat flow increases towards the young ocean ridges, whereas it is rather low on the old continental shields. It is not surprising that surface heat flow measurements, or even estimates, where performed, contributed greatly to our understanding of what happens inside the planets. In this article, I will review the results and the methods used in past heat flow measurements and speculate on the targets and design of future experiments. PMID:16286290

  16. Mpo - the Bepicolombo Mercury Planetary Orbiter.

    NASA Astrophysics Data System (ADS)

    Benkhoff, J.

    2008-09-01

    proximity of the Sun Since and considering that the advance Mercury's perihelion was explained in terms of relativistic spacetime curvature. MPO Scientific Instruments BepiColombo Mercury Planetary Orbiter's and Mercury Magnetospheric Orbiter's instruments were selected in November 2004, by ESA and JAXA respectively. The MPO will carry a highly sophisticated suit of eleven scientific instruments, ten of which will be provided by Principal Investigators through national funding by ESA Member States and one from Russia: BepiColombo Laser Altimeter (BELA) will characterise the topography and surface morphology of Mercury. It will also provide a digital terrain model that, compared with the data from the MORE instrument, will allow to obtain information about the internal structure, the geology, the tectonics, and the age of the planet's surface. The objectives of the Italian Spring Accelerometer (ISA) are strongly connected with those of the MORE experiment. Together the experiments can give information on Mercury's interior structure as well as test Einstein's theory of the General Relativity. Mercury Magnetometer (MPO-MAG) will provide measurements that will lead to the detailed description of Mercury's planetary magnetic field and its source, to better understand the origin, evolution and current state of the planetary interior , as well as the interaction between Mercury's magnetosphere with the planet's itself and with the solar wind. Mercury Thermal Infrared Spectrometer (MERTIS) will provide detailed information about the mineralogical composition of Mercury's surface layer with a high spectral resolution, crucial for selecting the valid model for origin and evolution of the planet. Mercury Gamma ray and Neutron Spectrometer (MGNS) will determine the elemental compositions of the surface and subsurface of Mercury, and will determine the regional distribution of volatile depositions on the polar areas which are permanently shadowed from the Sun. Mercury Imaging X

  17. Lunar and Planetary Science XXXVI, Part 13

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Contents include the following: A Fast, Non-Destructive Method for Classifying Ordinary Chondrite Falls Using Density and Magnetic Susceptibility. An Update on Results from the Magnetic Properties Experiments on the Mars Exploration Rovers, Spirit and Opportunity. Measurement Protocols for In Situ Analysis of Organic Compounds at Mars and Comets. Piping Structures on Earth and Possibly Mars: Astrobiological Implications. Uranium and Lead in the Early Planetary Core Formation: New Insights Given by High Pressure and Temperature Experiments. The Mast Cameras and Mars Descent Imager (MARDI) for the 2009 Mars Science Laboratory. MGS MOC: First Views of Mars at Sub-Meter Resolution from Orbit. Analysis of Candor Chasma Interior Layered Deposits from OMEGA/MEX Spectra. Analysis of Valley Networks on Valles Marineris Plateau Using HRSC/MEX Data. Solar Abundance of Elements from Neutron-Capture Cross Sections. Preliminary Evaluation of the Secondary Ion/Accelerator Mass Spectrometer, MegaSIMS. Equilibrium Landforms in the Dry Valleys of Antarctica: Implications for Landscape Evolution and Climate Change on Mars. Continued Study of Ba Isotopic Compositions of Presolar Silicon Carbide Grains from Supernovae. Paleoenviromental Evolution of the Holden-Uzboi Area. Stability of Magnesium Sulfate Minerals in Martian Environments. Tungsten Isotopic Constraints on the Formation and Evolution of Iron Meteorite Parent Bodies. Migration of Dust Particles and Volatiles Delivery to the Inner Planets. On the Sitting of Trapped Noble Gases in Insoluble Organic Matter of Primitive Meteorites. Trapping of Xenon Upon Evaporation-Condensation of Organic Matter Under UV Irradiation: Isotopic Fractionation and Electron Paramagnetic Resonance Analysis. Stability of Water on Mars. A Didactic Activity. Analysis of Coronae in the Parga Chasma Region, Venus. Photometric and Compositional Surface Properties of the Gusev Crater Region, Mars, as Derived from Multi-Angle, Multi-Spectral Investigation of

  18. Advances in Planetary Geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (Editor)

    1982-01-01

    Advances in Planetary Geology is a new series intended to serve the planetary geology community with a form for quick and thorough communications. There are no set lists of acceptable topics or formats, and submitted manuscripts will not undergo a formal review. All submissions should be in a camera ready form, preferably spaced, and submitted to the editor.

  19. Planetary Exploration in ESA

    NASA Technical Reports Server (NTRS)

    Schwehm, Gerhard H.

    2005-01-01

    A viewgraph presentation on planetary exploration in the European Space Agency is shown. The topics include: 1) History of the Solar System Material; 2) ROSETTA: The Comet Mission; 3) A New Name For The Lander: PHILAE; 4) The Rosetta Mission; 5) Lander: Design Characteristics; 6) SMART-1 Mission; 7) MARS Express VENUS Express; 8) Planetary Exploration in ESA The Future.

  20. Advanced planetary studies

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Results of planetary advanced studies and planning support are summarized. The scope of analyses includes cost estimation research, planetary mission performance, penetrator advanced studies, Mercury mission transport requirements, definition of super solar electric propulsion/solar sail mission discriminators, and advanced planning activities.

  1. Planetary Seismometers: An Overview

    NASA Astrophysics Data System (ADS)

    Knapmeyer, M.; Akito, A.; Bampasidis, G.; Banerdt, W. B.; Coustenis, A.; Fouch, M. J.; Garnero, E. J.; Khavroshkin, O.; Kobayashi, N.; Moussas, X.; Pike, W. T.; Seidensticker, K. J.; Solomonidou, A.; Yu, H.; Zakharov, A.

    2012-04-01

    Seismometers were part of lander payloads since the launch of Ranger 3 in early 1962, which was the first attempt to deliver scientific instruments to the surface of another celestial body. Since then, active and passive seismic experiments were conducted with great success on the Moon, and to a lesser extent on Mars and Venus. Proposals have been made or are in preparation for new experiments with single instruments or instrument networks on Venus, Moon, Mars, Phobos, Titan, Europa, and other bodies. One instrument (CASSE, sensitive for acoustic frequencies >= 30Hz) is currently flying to comet 67P/Churyumov-Gerasimenko on board of the Rosetta Mission. We give an overview of seismometers for use in planetary missions, including instruments of past and future missions. The focus is on the current developments as represented by the authors of the presentation. These encompass a Micro-Electromechanic System, several piezoelectric transducers that are able to resist strong decelerations, as well as new developments based on laser-interferometric sensing or hydrodynamic flow of electrolytic liquids.

  2. 76. INTERIOR, FIRST FLOOR, WING 1200 WEST, INTERIOR DEPARTMENT MUSEUM, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    76. INTERIOR, FIRST FLOOR, WING 1200 WEST, INTERIOR DEPARTMENT MUSEUM, LOBBY, BRONZE GRILL (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  3. On the stability of circumbinary planetary systems

    NASA Astrophysics Data System (ADS)

    Popova, E. A.; Shevchenko, I. I.

    2016-07-01

    The dynamics of circumbinary planetary systems (the systems in which the planets orbit a central binary) with a small binary mass ratio discovered to date is considered. The domains of chaotic motion have been revealed in the "pericentric distance-eccentricity" plane of initial conditions for the planetary orbits through numerical experiments. Based on an analytical criterion for the chaoticity of planetary orbits in binary star systems, we have constructed theoretical curves that describe the global boundary of the chaotic zone around the central binary for each of the systems. In addition, based on Mardling's theory describing the separate resonance "teeth" (corresponding to integer resonances between the orbital periods of a planet and the binary), we have constructed the local boundaries of chaos. Both theoretical models are shown to describe adequately the boundaries of chaos on the numerically constructed stability diagrams, suggesting that these theories are efficient in providing analytical criteria for the chaoticity of planetary orbits.

  4. 2nd International Planetary Probe Workshop

    NASA Technical Reports Server (NTRS)

    Venkatapathy, Ethiraj; Martinez, Ed; Arcadi, Marla

    2005-01-01

    Included are presentations from the 2nd International Planetary Probe Workshop. The purpose of the second workshop was to continue to unite the community of planetary scientists, spacecraft engineers and mission designers and planners; whose expertise, experience and interests are in the areas of entry probe trajectory and attitude determination, and the aerodynamics/aerothermodynamics of planetary entry vehicles. Mars lander missions and the first probe mission to Titan made 2004 an exciting year for planetary exploration. The Workshop addressed entry probe science, engineering challenges, mission design and instruments, along with the challenges of reconstruction of the entry, descent and landing or the aerocapture phases. Topics addressed included methods, technologies, and algorithms currently employed; techniques and results from the rich history of entry probe science such as PAET, Venera/Vega, Pioneer Venus, Viking, Galileo, Mars Pathfinder and Mars MER; upcoming missions such as the imminent entry of Huygens and future Mars entry probes; and new and novel instrumentation and methodologies.

  5. InSight Planetary Protection Status

    NASA Astrophysics Data System (ADS)

    Benardini, James; La Duc, Myron; Willis, Jason

    The NASA Discovery Program’s next mission, Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSIght), consists of a single spacecraft that will be launched aboard an Atlas V 401 rocket from Vandenberg Air Force Base (Space Launch Complex 3E) during the March 2016 timeframe. The overarching mission goal is to illuminate the fundamentals of formation and evolution of terrestrial planets by investigating the interior structure and processes of Mars. The flight system consists of a heritage cruise stage, aeroshell (heatshield and backshell), and Lander from the 2008 Phoenix mission. Included in the lander payload are various cameras, a seismometer, an auxiliary sensor suite to measure wind, temperature, and pressure, and a mole to penetrate the regolith (<5 meters) and assess the subsurface geothermal gradient of Mars. Being a Mars lander mission without life detection instruments, InSight has been designated a PP Category Iva mission. As such, planetary protection bioburden requirements apply which require microbial reduction procedures and biological burden reporting. The InSight project is current with required PP documentation, having completed an approved Planetary Protection Plan, Subsidiary PP Plans, and a PP Implementation Plan. The InSight mission’s early planetary protection campaign has commenced, coinciding with the fabrication and assembly of payload and flight system hardware and the baseline analysis of existing flight spares. A report on the status of InSight PP activities will be provided.

  6. Reports of Planetary Geology and Geophysics Program, 1984

    NASA Technical Reports Server (NTRS)

    Holt, H. E. (Compiler); Watters, T. R. (Compiler)

    1985-01-01

    Topics include outer planets and satellites; asteroids and comets; Venus; lunar origin and solar dynamics; cratering process; planetary interiors, petrology, and geochemistry; volcanic processes; aeolian processes and landforms; fluvial processes; geomorphology; periglacial and permafrost processes; remote sensing and regolith studies; structure, tectonics, and stratigraphy; geological mapping, cartography, and geodesy; and radar applications.

  7. Workshop on Mercury: Space Environment, Surface, and Interior

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This volume contains abstracts that have been accepted for presentation at the Workshop on Mercury: Space Environment, Surface, and Interior, October 4-5, 2001. The Scientific Organizing Committee consisted of Mark Robinson (Northwestern University), Marty Slade (Jet Propulsion Laboratory), Jim Slavin (NASA Goddard Space Flight Center), Sean Solomon (Carnegie Institution), Ann Sprague (University of Arizona), Paul Spudis (Lunar and Planetary Institute), G. Jeffrey Taylor (University of Hawai'i), Faith Vilas (NASA Johnson Space Center), Meenakshi Wadhwa (The Field Museum), and Thomas Watters (National Air and Space Museum). Logistics, administrative, and publications support were provided by the Publications and Program Services Departments of the Lunar and Planetary Institute.

  8. Chemical exchange in the interior of water-rich exoplanets

    NASA Astrophysics Data System (ADS)

    Tobie, G.; Choblet, G.; Grasset, O.

    2015-10-01

    Since the discovery of the first exoplanet in 1995 [1], the number of detected exoplanets has grown nearly exponentially [2]. We have learnt from the existing dataset that our Solar System is rather unusual. Exoplanet surveys revealed notably that exoplanets intermediate between Earth and Neptune are surprisingly common, while notably absent in the Solar System [3]. Model mass-radius relationships indicate a great diversity of interior composition and atmospheric extent for the Super-Earth/Mini- Neptune-planet class [e.g. 4]. The observed continuum between Earth-sized and Neptune-sized planets challenges our understanding of planet formation and evolution, which has been biased for many years by our vision of the Solar System. Planetary worlds are probably much more diverse than originally thought, with a wide range of water and other volatile content. In the Solar System, there is a strong dichotomy between the inner system with dry planetary objects having a very small volatile fraction (<0.1 %), and the outer solar system where water ice constitutes a large fraction of solid phase (> 20%). The volatile contents among other systems likely vary more gradually, and a large fraction of exoplanets with sizes intermediate between Earth and Neptune may have a water content exceeding several percents. The existence of massive water envelops around these planets may significantly affect the internal evolution and chemical exchanges between the deep interior and the atmosphere [e.g. 5]. Due to the very high-pressure expected inside these water-rich planets, especially for the the most massive ones, most of the water will be in the form of a high-pressure ice phase (ice VII) [6,7], the presence of liquid water being limited only to the first kilometres. The thermal structure and dynamics of these thick icy mantles are expected to control the heat and chemical transport from the silicate-rich interior to the surface [8,9], in a way analogous to the internal processes

  9. Meaning of Interior Tomography

    PubMed Central

    Wang, Ge; Yu, Hengyong

    2013-01-01

    The classic imaging geometry for computed tomography is for collection of un-truncated projections and reconstruction of a global image, with the Fourier transform as the theoretical foundation that is intrinsically non-local. Recently, interior tomography research has led to theoretically exact relationships between localities in the projection and image spaces and practically promising reconstruction algorithms. Initially, interior tomography was developed for x-ray computed tomography. Then, it has been elevated as a general imaging principle. Finally, a novel framework known as “omni-tomography” is being developed for grand fusion of multiple imaging modalities, allowing tomographic synchrony of diversified features. PMID:23912256

  10. Europlanet - Joining the European Planetary Research Information Service

    NASA Astrophysics Data System (ADS)

    Capria, M. T.; Chanteur, G.; Schmidt, W.

    2009-04-01

    The "Europlanet Research Infrastructure - Europlanet RI", supported by the European Commission's Framework Program 7, aims at integrating major parts of the distributed European Planetary Research infrastructure with as diverse components as space exploration, ground-based observations, laboratory experiments and numerical model-ling teams. A central part of Europlanet RI is the "Integrated and Distributed Information Service" or Europlanet-IDIS which intends to provide easy Web-based access to information about scientists and teams working in related fields, observatories or laboratories with capabilities possibly beneficial to planetary research, modelling expertise useful for planetary science and observations from space-based, ground-based or laboratory measurements. As far as the type of data and their access methods allow, IDIS will provide Virtual Observatory (VO) like access to a variety of data from distributed sources and tools to compare and integrate this information to further data analysis and re-search. IDIS itself is providing a platform for information and data sharing and for data mining. It is structured as a network of thematic nodes each concentrating on a sub-set of research areas in planetary sciences. But the most important elements of IDIS and the whole Europlanet RI are the single scientists, institutes, laboratories, observatories and mission project teams. Without them the whole effort would remain an empty shell. How can an interested individual or team join this activity and what are the benefits to be expected from the related effort? The poster gives detailed answers to these questions. Here some highlights: 1. Locate from the Europlanet web pages (addresses see below) the thematic node best related to the own field of expertise. This might be more than one. 2. Define which services you want to offer to the community: just the contact address, field of competence, off-line access to data on request or even on-line searchable access