WorldWideScience

Sample records for airless planetary bodies

  1. Dust charging and transport on airless planetary bodies

    Science.gov (United States)

    Wang, X.; Schwan, J.; Hsu, H.-W.; Grün, E.; Horányi, M.

    2016-06-01

    We report on laboratory experiments to shed light on dust charging and transport that have been suggested to explain a variety of unusual phenomena on the surfaces of airless planetary bodies. We have recorded micron-sized insulating dust particles jumping to several centimeters high with an initial speed of ~0.6 m/s under ultraviolet illumination or exposure to plasmas, resulting in an equivalent height of ~0.11 m on the lunar surface that is comparable to the height of the so-called lunar horizon glow. Lofted large aggregates and surface mobilization are related to many space observations. We experimentally show that the emission and re-absorption of photoelectron and/or secondary electron at the walls of microcavities formed between neighboring dust particles below the surface are responsible for generating unexpectedly large negative charges and intense particle-particle repulsive forces to mobilize and lift off dust particles.

  2. Electrostatic dust transport on the surfaces of airless bodies

    Science.gov (United States)

    Wang, X.; Schwan, J.; Hsu, H. W.; Horanyi, M.

    2015-12-01

    The surfaces of airless bodies are charged due to the exposure to solar wind plasma and UV radiation. Dust particles on the regolith of these surfaces can become charged, and may move and even get lofted due to electrostatic force. Electrostatic dust transport has been a long-standing problem that may be related to many observed phenomena on the surfaces of airless planetary bodies, including the lunar horizon glow, the dust ponds on asteroid Eros, the spokes in Saturn's rings, and more recently, the collection of dust particles ejected off Comet 67P, observed by Rosetta. In order to resolve these puzzles, a handful of laboratory experiments have been performed in the past and demonstrated that dust indeed moves and lifts from surfaces exposed to plasma. However, the exact mechanisms for the mobilization of dust particles still remain a mystery. Current charging models, including the so-called "shared charge model" and the charge fluctuation theory, will be discussed. It is found that neither of these models can explain the results from either laboratory experiments or in-situ observations. Recently, single dust trajectories were captured with our new dust experiments, enabling novel micro-scale investigations. The particles' initial launch speeds and size distributions are analyzed, and a new so-called "patched charge model" is proposed to explain our findings. We identify the role of plasma micro-cavities that are formed in-between neighboring dust particles. The emitted secondary or photo- electrons are proposed to be absorbed inside the micro-cavities, resulting in significant charge accumulation on the exposed patches of the surfaces of neighboring particles. The resulting enhanced Coulomb force (repulsion) between particles is likely the dominant force to mobilize and lift them off the surface. The role of other properties, including surface morphology, cohesion and photoelectron charging, will also be discussed.

  3. Particle Radiation Environments and Their Effects at Planetary Surfaces of Airless Bodies: Remote Sensing Lessons Learned at the Moon by LRO/CRaTER and Extension to Other Planetary Objects

    Science.gov (United States)

    Spence, H. E.; Schwadron, N. A.; Wilson, J. K.; Jordan, A. P.; Winslow, R.; Joyce, C.; Looper, M. D.; Case, A. W.; Stubbs, T. J.; Zeitlin, C.; Blake, J. B.; Kasper, J. C.; Mazur, J. E.; Smith, S. S.; Townsend, L. W.

    2015-11-01

    We summarize the physics of GCR and SEP interactions with the Moon's surface and quantify how these same processes operate at similar airless objects throughout the solar system, including at Mercury, Mars' moons, asteroids, and the Pluto system.

  4. Grain-scale thermoelastic stresses and spatiotemporal temperature gradients on airless bodies, implications for rock breakdown

    CERN Document Server

    Molaro, Jamie L; Langer, Steve A

    2015-01-01

    Thermomechanical processes such as fatigue and shock have been suggested to cause and contribute to rock breakdown on Earth, and on other planetary bodies, particularly airless bodies in the inner solar system. In this study, we modeled grain-scale stresses induced by diurnal temperature variations on simple microstructures made of pyroxene and plagioclase on various solar system bodies. We found that a heterogeneous microstructure on the Moon experiences peak tensile stresses on the order of 100 MPa. The stresses induced are controlled by the coefficient of thermal expansion and Young's modulus of the mineral constituents, and the average stress within the microstructure is determined by relative volume of each mineral. Amplification of stresses occurs at surface-parallel boundaries between adjacent mineral grains and at the tips of pore spaces. We also found that microscopic spatial and temporal surface temperature gradients do not correlate with high stresses, making them inappropriate proxies for investig...

  5. Modelling the thermal emission from airless planetary surfaces and sub-surfaces

    OpenAIRE

    Leyrat, C.; Le Gall, Alice; Stolzenbach, Aurélien; Lellouch, Emmanuel

    2012-01-01

    Both the Cassini (NASA/ESA/ASI) and Rosetta (ESA) spacecrafts have onboard a radiometer operating at relatively large wavelengths, respectively in the microwave and sub-millimetric domains. At such wavelengths, these instruments sense the thermal emission not only from the surface but also from a section of the sub-surface of the targeted bodies. As a consequence, the interpretation of radiometric data collected over the airless icy satellites of Saturn by Cassini and over the comet 67P/Chury...

  6. Laser Ablation Mass Spectrometer (LAMS) as a Standoff Analyzer in Space Missions for Airless Bodies

    Science.gov (United States)

    Li, X.; Brinckerhoff, W. B.; Managadze, G. G.; Pugel, D. E.; Corrigan, C. M.; Doty, J. H.

    2012-01-01

    A laser ablation mass spectrometer (LAMS) based on a time-of-flight (TOF) analyzer with adjustable drift length is proposed as a standoff elemental composition sensor for space missions to airless bodies. It is found that the use of a retarding potential analyzer in combination with a two-stage reflectron enables LAMS to be operated at variable drift length. For field-free drift lengths between 33 cm to 100 cm, at least unit mass resolution can be maintained solely by adjustment of internal voltages, and without resorting to drastic reductions in sensitivity. Therefore, LAMS should be able to be mounted on a robotic arm and analyze samples at standoff distances of up to several tens of cm, permitting high operational flexibility and wide area coverage of heterogeneous regolith on airless bodies.

  7. The electrostatic plasma environment of a small airless body under non-aligned plasma flow and UV conditions

    Science.gov (United States)

    Poppe, A. R.; Zimmerman, M. I.; Halekas, J. S.; Farrell, W. M.

    2015-12-01

    Airless bodies interact with a wide variety of plasma environments throughout the solar system. For many objects, incident plasma is nearly co-aligned with solar ultraviolet radiation leading to the development of a positively charged dayside photoelectron sheath and a negatively charged nightside plasma sheath. Other objects, however, are present in environments where the plasma flow and solar UV radiation may not co-align. These environments include, for example, the moons of Mars as they pass through the deflected Martian magnetosheath, and many of the moons of the outer planets, which are embedded in co-rotating planetary magnetospheres. The decoupling of the plasma flow and UV incidence vectors opens up a wide range of possible surface charging and near-object plasma conditions as a function of the relative plasma-UV incidence angle. Here, we report on a series of simulations of the plasma interaction of a small body (effectively smaller than both electron and ion gyroradii) with both flowing plasma and UV radiation for different plasma-UV incidence angles using an electrostatic treecode model. We describe the plasma and electric field environment both on the object surface and in the interaction region surrounding the object, including complex surface charge and electric field distributions, interactions between surface-generated photoelectrons and ambient plasma electrons, and complex potential distributions, all of which vary as a function of the relative plasma flow-UV angle. We also show that in certain conditions, non-monotonic potential structures may exist around such objects, partially similar to those found at Earth's Moon.

  8. Analogue Materials Measured Under Simulated Lunar and Asteroid Environments: Application to Thermal Infrared Measurements of Airless Bodies

    Science.gov (United States)

    Donaldson Hanna, K. L.; Pieters, C. M.; Patterson, W., III; Moriarty, D.

    2012-12-01

    Remote sensing observations provide key insights into the composition and evolution of planetary surfaces. A fundamentally important component to any remote sensing study of planetary surfaces is laboratory measurements of well-characterized samples measured under the appropriate environmental conditions. The near-surface vacuum environment of airless bodies like the Moon and asteroids creates a thermal gradient in the upper hundred microns of regolith. Lab studies of particulate rocks and minerals as well as selected lunar soils under vacuum and lunar-like conditions have identified significant effects of this thermal gradient on thermal infrared (TIR) spectral measurements [e.g. Logan et al. 1973, Salisbury and Walter 1989, Thomas et al. 2010, Donaldson Hanna et al. 2012]. Compared to ambient conditions, these effects include: (1) the Christiansen feature (CF), an emissivity maximum diagnostic of mineralogy and average composition, shifts to higher wavenumbers and (2) an increase in spectral contrast of the CF relative to the Reststrahlen bands (RB), the fundamental molecular vibration bands due to Si-O stretching and bending. Such lab studies demonstrate the high sensitivity of TIR emissivity spectra to environmental conditions under which they are measured. The Asteroid and Lunar Environment Chamber (ALEC) is the newest addition to the RELAB at Brown University. The vacuum chamber simulates the space environment experienced by the near-surface soils of the Moon and asteroids. The internal rotation stage allows for six samples and two blackbodies to be measured without breaking vacuum (emission environment (mimicking the space environment) for heated samples to radiate into. Sample cups can be heated in one of three configurations: (1) from below using heaters embedded in the base of the sample cup, (2) from above using a solar-like radiant heat source, and (3) from below and above to allow the magnitude of the thermal gradient to be examined. ALEC is connected

  9. Adhesion Between Volcanic Glass and Spacecraft Materials in an Airless Body Environment

    Science.gov (United States)

    Berkebile, Stephen; Street, Kenneth W., Jr.; Gaier, James R.

    2012-01-01

    The successful exploration of airless bodies, such as the Earth s moon, many smaller moons of the outer planets (including those of Mars) and asteroids, will depend on the development and implementation of effective dust mitigation strategies. The ultrahigh vacuum environment (UHV) on the surfaces of these bodies, coupled with constant ion and photon bombardment from the Sun and micrometeorite impacts (space weathering), makes dust adhesion to critical spacecraft systems a severe problem. As a result, the performance of thermal control surfaces, photovoltaics and mechanical systems can be seriously degraded even to the point of failure. The severe dust adhesion experienced in these environments is thought to be primarily due to two physical mechanisms, electrostatic attraction and high surface energies, but the dominant of these has yet to be determined. The experiments presented here aim to address which of these two mechanisms is dominant by quantifying the adhesion between common spacecraft materials (polycarbonate, FEP and PTFE Teflon, (DuPont) Ti-6-4) and a synthetic noritic volcanic glass, as a function of surface cleanliness and triboelectric charge transfer in a UHV environment. Adhesion force has been measured between pins of spacecraft materials and a plate of synthetic volcanic glass by determining the pull-off force with a torsion balance. Although no significant adhesion is observed directly as a result of high surface energies, the adhesion due to induced electrostatic charge is observed to increase with spacecraft material cleanliness, in some cases by over a factor of 10, although the increase is dependent on the particular material pair. The knowledge gained by these studies is envisioned to aid the development of new dust mitigation strategies and improve existing strategies by helping to identify and characterize mechanisms of glass to spacecraft adhesion for norite volcanic glass particles. Furthermore, the experience of the Apollo missions

  10. Survival times of meter-sized rock boulders on the surface of airless bodies

    Science.gov (United States)

    Basilevsky, A. T.; Head, J. W.; Horz, F.; Ramsley, K.

    2015-11-01

    Rock boulders are typical features of the surfaces of many airless bodies, so the possibility of estimating their potential survival times may provide insights into the rates of surface-modification processes. As an opening point of this study we employ estimates of the survival times of meter-sized boulders on the surface of the Moon based on analysis of the spatial density of boulders on the rims of small lunar craters of known absolute age (Basilevsky et al., 2013), and apply them, with necessary corrections, to boulders on other bodies. In this approach the major factor of rock destruction is considered to be impacts of meteorites. However another factor of the rock destruction, thermal fatigue due to day-night cycling, does exist and it was claimed by Delbo et al. (2014) as being more important than meteorite impacts. They concluded this on the basis of known presence of fine material on the surface of small asteroids, claiming that due to extremely low gravity on those bodies, the products of meteorite bombardment should leave these bodies, and thus their presence indicates that the process of thermal fatigue should be much more effective there. Delbo et al. (2014) made laboratory experiments on heating-cooling centimeter-sized samples of chondrites and, applying some assumptions and theoretical modeling concluded that, for example, at 1 AU distance from the Sun, the lifetime of 10 cm rock fragments on asteroids with period of rotation from 2.2 to 6 h should be only ~103 to 104 years (that is ~3.5×106 to 1.5×107 thermal cycles) and the larger the rock, the faster it should be destroyed. In response to those conclusions we assessed the results of earlier laboratory experiments, which show that only a part of comminuted material produced by high-velocity impacts into solid rocks is ejected from the crater while another part is not ejected but stays exposed on the target surface and is present in its subsurface. This means that the presence of

  11. Characterizing Water and Hydroxyl on Airless Bodies from Vacuum UV and IR Measurements

    Science.gov (United States)

    Hibbitts, Charles A.

    2015-11-01

    Water exists in the surfaces of airless bodies as ice and potentially as adsorbed species [1], either as molecular water or dissociated into hydroxyl when bulk water (ice) is not stable [2]. All physical states of water have a strong spectral signatures in the infrared from 2.7 to 3-um because of a fundamental OH-cation or H-O-H stretch vibration. But the IR is not always definitive of physical state. Although a band at 3.07 um is associated with water ice, an almost identical band exists in some hydrated minerals. Brucite, an alteration product of olivine, possesses this band [6] as does goethite, another alteration mineral of basalts [7]. In fact, the 3.05-um band on Ceres, which was initially attributed to water ice, has more recently been attributed to brucite [6]. Spectral observations in the UV can potentially resolve this degeneracy. In the UV, water ice possesses a very strong band near 180 nm [8], but adsorbed molecular water does not induce a band. Because of this, a combination of UV measurements at wavelengths from ~ 150 nm to ~200 nm and IR measurements near 3 um can discriminate ice from adsorbed water. The UV region, however, is also sensitive to silicate composition, with iron bearing minerals having a strong OMCT absorption feature near 300 nm and again shortward of 200 nm, that can potentially be a source of confusion between the identification of iron-poor minerals and water ice. In conclusion, the IR can sense all three forms of water (ice, adsorbed molecular water, and hydroxyl) and the UV, being sensitive to ice, may potentially be used either alone or with the IR to identify water ice separately from other phases of hydration.References: [1] Hibbitts et al., Icarus, 213, 64-72, 2011. [2] Schorghofer, N and G.J. Taylor, JGR, 112, E02010,doi:10.1029, 2007; [3] Poston et al., JGR, 118, 105-115, 2013; [4] Dyar et al., Icarus, 208,425-437, 2010; [5] Zeller et al., JGR, 71, 4855-4860, 1966;[6] Milliken, R.E. and A.S. Rivkin, Nature Geosci, DOI: 10

  12. High-Resolution and Analytical TEM Investigation of Space Radiation Processing Effects in Primitive Solar System Materials and Airless Planetary Surface Environments

    Science.gov (United States)

    Christoffersen, R.; Rahman, Z.; Keller, L. P.; Dukes, C.; Baragiola, R.

    2012-01-01

    Energetic ions present in the diverse plasma conditions in space play a significant role in the formation and modification of solid phases found in environments ranging from the interstellar medium (ISM) to the surfaces of airless bodies such as asteroids and the Moon. These effects are often referred to as space radiation processing, a term that encompasses changes induced in natural space-exposed materials that may be only structural, such as in radiation-induced amorphization, or may involve ion-induced nanoscale to microscale chemical changes, as occurs in preferential sputtering and ion-beam mixing. Ion sputtering in general may also be responsible for partial or complete erosion of space exposed materials, in some instances possibly bringing about the complete destruction of free-floating solid grains in the ISM or in circumstellar nebular dust clouds. We report here on two examples of the application of high-resolution and analytical transmission electron microscopy (TEM) to problems in space radiation processing. The first problem concerns the role of space radiation processing in controlling the overall fate of Fe sulfides as hosts for sulfur in the ISM. The second problem concerns the known, but as yet poorly quantified, role of space radiation processing in lunar space weathering.

  13. On the average temperature of airless spherical bodies and the magnitude of Earth’s atmospheric thermal effect

    OpenAIRE

    Volokin, Den; ReLlez, Lark

    2014-01-01

    The presence of atmosphere can appreciably warm a planet’s surface above the temperature of an airless environment. Known as a natural Greenhouse Effect (GE), this near-surface Atmospheric Thermal Enhancement (ATE) as named herein is presently entirely attributed to the absorption of up-welling long-wave radiation by greenhouse gases. Often quoted as 33 K for Earth, GE is estimated as a difference between planet’s observed mean surface temperature and an effective radiating temperature calcul...

  14. TEM Analyses of Itokawa Regolith Grains and Lunar Soil Grains to Directly Determine Space Weathering Rates on Airless Bodies

    Science.gov (United States)

    Berger, Eve L.; Keller, Lindsay P.; Christoffersen, Roy

    2016-01-01

    Samples returned from the moon and Asteroid Itokawa by NASA's Apollo Missions and JAXA's Hayabusa Mission, respectively, provide a unique record of their interaction with the space environment. Space weathering effects result from micrometeorite impact activity and interactions with the solar wind. While the effects of solar wind interactions, ion implantation and solar flare particle track accumulation, have been studied extensively, the rate at which these effects accumulate in samples on airless bodies has not been conclusively determined. Results of numerical modeling and experimental simulations do not converge with observations from natural samples. We measured track densities and rim thicknesses of three olivine grains from Itokawa and multiple olivine and anorthite grains from lunar soils of varying exposure ages. Samples were prepared for analysis using a Leica EM UC6 ultramicrotome and an FEI Quanta 3D dual beam focused ion beam scanning electron microscope (FIB-SEM). Transmission electron microscope (TEM) analyses were performed on the JEOL 2500SE 200kV field emission STEM. The solar wind damaged rims on lunar anorthite grains are amorphous, lack inclusions, and are compositionally similar to the host grain. The rim width increases as a smooth function of exposure age until it levels off at approximately 180 nm after approximately 20 My (Fig. 1). While solar wind ion damage can only accumulate while the grain is in a direct line of sight to the Sun, solar flare particles can penetrate to mm-depths. To assess whether the track density accurately predicts surface exposure, we measured the rim width and track density in olivine and anorthite from the surface of rock 64455, which was never buried and has a surface exposure age of 2 My based on isotopic measurements. The rim width from 64455 (60-70nm) plots within error of the well-defined trend for solar wind amorphized rims in Fig. 1. Measured solar flare track densities are accurately reflecting the

  15. Design of Double-gun High-pressure Airless Spraying Machine’s Pump Body%双枪高压无气喷涂机的泵体结构设计

    Institute of Scientific and Technical Information of China (English)

    马如宏; 俞俊海

    2015-01-01

    为了解决目前国内双枪高压无气喷涂机紧缺的现状,通过对高压无气喷涂机的分析与研究,研制出一种新型的双枪高压无气喷涂机的泵体。并基于 Fluent软件分析了该泵体管路的压力和速度的变化。泵体有一个进料口,两个出料口,输漆管采用分段拼接式,方便携带和拆卸,不受喷涂距离的限制。%In order to solve the shortage of double-gun high-pressure airless spraying machine in China ,based on the analysis and research on high-pressure airless spraying machine ,a new type of double-gun high-pressure airless spraying machine’s pump body is developed .With a feed port ,two discharging mouth ,and the segmented painting tube ,the pump body is convenient to carry and remove ,not restricted by spraying distance .The changes of pipeline pressure and spaying speed is analyzed by Fluent software .

  16. Disintegrating Planetary Bodies Around a White Dwarf

    Science.gov (United States)

    Kohler, Susanna

    2016-02-01

    Several months ago, the discovery of WD 1145+017 was announced. This white dwarf appears to be orbited by planetary bodies that are actively disintegrating due to the strong gravitational pull of their host. A follow-up study now reveals that this system has dramatically evolved since its discovery.Signs of DisruptionPotential planetary bodies orbiting a white dwarf would be exposed to a particular risk: if their orbits were perturbed and they passed inside the white dwarfs tidal radius, they would be torn apart. Their material could then form a debris disk around the white dwarf and eventually be accreted.Interestingly, we have two pieces of evidence that this actually happens:Weve observed warm, dusty debris disks around ~4% of white dwarfs, andThe atmospheres of ~25-50% of white dwarfs are polluted by heavy elements that have likely accreted recently.But in spite of this indirect evidence of planet disintegration, wed never observed planetary bodies actively being disrupted around white dwarfs until recently.Unusual TransitsIn April 2015, observations by Keplers K2 mission revealed a strange transit signal around WD 1145+017, a white dwarf 570 light-years from Earth that has both a dusty debris disk and a polluted atmosphere. This signal was interpreted as the transit of at least one, and possibly several, disintegrating planetesimals.In a recent follow-up, a team of scientists led by Boris Gnsicke (University of Warwick) obtained high-speed photometry of WD 1145+017 using the ULTRASPEC camera on the 2.4m Thai National Telescope. These observations were taken in November and December of 2015 roughly seven months after the initial photometric observations of the system. They reveal that dramatic changes have occurred in this short time.Rapid EvolutionA sample light curve from TNT/ULTRASPEC, obtained in December 2015 over 3.9 hours. Many varied transits are evident (click for a better view!). Transits labeled in color appear across multiple nights. [Gnsicke et al

  17. Planetary3br: Three massive body resonance calculator

    Science.gov (United States)

    Gallardo, Tabaré

    2016-07-01

    Given two planets P1 and P2 with arbitrary orbits, planetary3br calculates all possible semimajor axes that a third planet P0 can have in order for the system to be in a three body resonance; these are identified by the combination k0*P0 + k1*P1 + k2*P2. P1 and P2 are assumed to be not in an exact two-body resonance. The program also calculates three "strengths" of the resonance, one for each planet, which are only indicators of the dynamical relevance of the resonance on each planet. Sample input data are available along with the Fortran77 source code.

  18. Dust environment of an airless object: A phase space study with kinetic models

    Science.gov (United States)

    Kallio, E.; Dyadechkin, S.; Fatemi, S.; Holmström, M.; Futaana, Y.; Wurz, P.; Fernandes, V. A.; Álvarez, F.; Heilimo, J.; Jarvinen, R.; Schmidt, W.; Harri, A.-M.; Barabash, S.; Mäkelä, J.; Porjo, N.; Alho, M.

    2016-01-01

    property of dust particles at different initial velocity (v0) and initial mass per charge (m/q) ratio were analysed. The study especially identifies regions in the phase space where the electric field within a non-quasineutral plasma region above the surface of the object, the Debye layer, becomes important compared with the gravitational force. Properties of the dust particles in the phase space region where the electric field plays an important role are studied by a 3D Monte Carlo model. The current DPEM modelling suite does not include models of how dust particles are initially injected from the surface. Therefore, the presented phase space study cannot give absolute 3D dust density distributions around the analysed airless objects. For that, an additional emission model is necessary, which determines how many dust particles are emitted at various places on the analysed (v0, m/q)-phase space. However, this study identifies phase space regions where the electric field within the Debye layer plays an important role for dust particles. Overall, the initial results indicate that when a realistic dust emission model is available, the unified lunar based DPEM modelling suite is a powerful tool to study globally and locally the dust environments of airless bodies such as planetary moons, Mercury, asteroids and non-active comets far from the Sun.

  19. Ceres' deformational surface features compared to other planetary bodies.

    Science.gov (United States)

    von der Gathen, Isabel; Jaumann, Ralf; Krohn, Katrin; Buczkowski, Debra L.; Elgner, Stephan; Kersten, Elke; Matz, Klaus-Dieter; Nass, Andrea; Otto, Katharina; Preusker, Frank; Roatsch, Thomas; Schröder, Stefanus E.; Schulzeck, Franziska; Stephan, Katrin; Wagner, Roland; De Sanctis, Maria C.; Schenk, Paul; Scully, Jennifer E. C.; Williams, Dave A.; Raymond, Carol A.

    2016-04-01

    On March 2015, NASA's Dawn spacecraft arrived at the dwarf planet Ceres and has been providing images of its surface. Based on High Altitude Mapping Orbiter (HAMO) clear filter images (140 m/px res.), a Survey mosaic (~400 m/px) and a series of Low Altitude Mapping Orbiter (LAMO) clear filter images (35 m/px) of the Dawn mission [1], deformational features are identified on the surface of Ceres. In order to further our knowledge about the nature and origin of these features, we start a comparative analysis of similar features on different planetary bodies, like Enceladus, Ganymede and the Moon, based on images provided by the Cassini, Galileo and Lunar Orbiter mission. This study focuses on the small scale fractures, mostly located on Ceres' crater floors, in comparison with crater fractures on the planetary bodies named above. The fractures were analyzed concerning the morphology and shape, the distribution, orientation and possible building mechanisms. On Ceres, two different groups of fractures are distinct. The first one includes fractures, normally arranged in subparallel pattern, which are usually located on crater floors, but also on crater rims. Their sense of direction is relatively uniform but in some cases they get deformed by shearing. The second group consists of joint systems, which spread out of one single location, sometimes arranged concentric to the crater rim. They were likely formed by cooling-melting processes linked to the impact process or up doming material. Fractures located on crater floors are also common on the icy satellite Enceladus [3]. While Enceladus' fractures don't seem to have a lot in common compared to those on Ceres, we assume that similar fracture patterns and therefore similar building mechanism can be found e.g. on Ganymede and especially on the Moon [2]. Further work will include the comparison of the fractures with additional planetary bodies and the trial to explain why fracturing e.g. on Enceladus differs from that on

  20. Dust Ejection from Planetary Bodies by Temperature Gradients: Laboratory Experiments

    CERN Document Server

    Kelling, Thorben; Kocifaj, Miroslav; Klacka, Jozef; Reiss, Dennis

    2011-01-01

    Laboratory experiments show that dusty bodies in a gaseous environment eject dust particles if they are illuminated. We find that even more intense dust eruptions occur when the light source is turned off. We attribute this to a compression of gas by thermal creep in response to the changing temperature gradients in the top dust layers. The effect is studied at a light flux of 13 kW/(m*m) and 1 mbar ambient pressure. The effect is applicable to protoplanetary disks and Mars. In the inner part of protoplanetary disks, planetesimals can be eroded especially at the terminator of a rotating body. This leads to the production of dust which can then be transported towards the disk edges or the outer disk regions. The generated dust might constitute a significant fraction of the warm dust observed in extrasolar protoplanetary disks. We estimate erosion rates of about 1 kg/s for 100 m parent bodies. The dust might also contribute to subsequent planetary growth in different locations or on existing protoplanets which ...

  1. Planetary and satellite three body mean motion resonances

    CERN Document Server

    Gallardo, Tabaré; Badano, Luciana

    2016-01-01

    We propose a semianalytical method to compute the strengths on each of the three massive bodies participating in a three body mean motion resonance (3BR). Applying this method we explore the dependence of the strength on the masses, the orbital parameters and the order of the resonance and we compare with previous studies. We confirm that for low eccentricity low inclination orbits zero order resonances are the strongest ones; but for excited orbits higher order 3BRs become also dynamically relevant. By means of numerical integrations and the construction of dynamical maps we check some of the predictions of the method. We numerically explore the possibility of a planetary system to be trapped in a 3BR due to a migrating scenario. Our results suggest that capture in a chain of two body resonances is more probable than a capture in a pure 3BR. When a system is locked in a 3BR and one of the planets is forced to migrate the other two can react migrating in different directions. We exemplify studying the case of...

  2. ENA diagnostics of the solar wind interaction with planetary bodies

    Science.gov (United States)

    Barabash, S.

    We define energetic neutral atoms (ENA) as neutrals moving with a velocity much greater than an escape velocity of a central body. Since gravitational banding of trajectories is negligible and electromagnetic forces do not affect their motion, ENAs propagate similar to photons and can be used to diagnose and image parent populations and processes. There are two basic mechanisms generating ENAs, namely, charge - exchange and sputtering of atoms from surfaces. The charge - exchange can occur both in the plasma - neutral gas and plasma - solid material interactions. The former normally takes place between singly charged magnetospheric ions and cool exospheric gasses while the later between ions and dust particles or surfaces (backscattering). Precipitation of energetic (> 1 keV) ions onto surfaces results in sputtering. Since the tails of the sputtered atom distribution functions fall-of as E-2 (Thompson - Sigmund spectrum), the fluxes of atom with energies more than 10 eV (typical escape energies for heavy particles) are substantial and can be used for imaging. In different planetary environments, ENA imaging can reveal: solar wind proton and planetary (oxygen) ion distributions (Mars, Venus), effects of atmospheric sputtering (Mars, Venus), neutral gas distributions (Io / Europa torus, Phobos torus), dust distributions (Saturn), ion precipitation patterns (ENA-aurora on Mercury, magnetic anomalies on the Moon), exospheric sources and surface composition (Mercury and the Moon), global ion distribution inside magnetospheres (Mercury, Saturn), global dynamics of the magnetosphere (ENA-flushes at Mercury, Mars environment response to the interplanetary disturbances). The focus of the concrete examples of the ENA diagnostic technique application will be on the latest ENA measurements from the ASPERA-3 and 4 experiments at Mars and Venus.

  3. Super-Earths: A New Class of Planetary Bodies

    CERN Document Server

    Haghighipour, Nader

    2011-01-01

    Super-Earths, a class of planetary bodies with masses ranging from a few Earth-masses to slightly smaller than Uranus, have recently found a special place in the exoplanetary science. Being slightly larger than a typical terrestrial planet, super-Earths may have physical and dynamical characteristics similar to those of Earth whereas unlike terrestrial planets, they are relatively easier to detect. Because of their sizes, super-Earths can maintain moderate atmospheres and possibly dynamic interiors with plate tectonics. They also seem to be more common around low-mass stars where the habitable zone is in closer distances. This article presents a review of the current state of research on super-Earths, and discusses the models of the formation, dynamical evolution, and possible habitability of these objects. Given the recent advances in detection techniques, the detectability of super-Earths is also discussed, and a review of the prospects of their detection in the habitable zones of low-mass stars is presente...

  4. Comparative tectonic features on Ceres and other planetary bodies

    Science.gov (United States)

    Roatsch, T.; von der Gathen, I.; Jaumann, R.; Krohn, K.; Otto, K.; Schulzeck, F.; Williams, D. A.; Buczkowski, D.; De Sanctis, M. C.; Elgner, S.; Kersten, E.; Matz, K. D.; Naß, A.; Preusker, F.; Schenk, P.; Schroeder, S.; Stephan, K.; Wagner, R. J.; Raymond, C. A.; Russell, C. T.

    2015-12-01

    Dawn Framing Camera images of Ceres' surface indicate that tectonic processes have played an important role in the surface formation history and alterations. We study structures expected to be the result of tectonic deformation and crustal stresses, which may enable us to reconstruct the formation process of the surface and the topographic signature. Tectonic features on Ceres such as troughs, ridges, scarps, fractures, depressions and domes are analogous to those on other planetary bodies like Enceladus, Ganymede, Europa and Mercury. Comparing these surface features will provide additional information about possible scenarios of crustal formation on Ceres. First investigations show that craters, like Urvara (46°S and 249°E), display sets of trenches radiating from the craters interior. They were likely formed by extensional tectonics linked to the impact. Similar features were also found on Mercury's surface. It is expected that other tectonic deformations on Ceres also influence the appearance of craters and crater walls. Comparatively small scale fissures on Ceres' surface, frequently arranged subparallel, seem to appear in terrain that looks smooth in the images. Fractures, cracks and scarps on Ceres can be found on Enceladus, Europa and Mercury in similar patterns. The "tiger stripes" on Enceladus are possible large scale analogous. Ridges on Europa, Enceladus and Ganymede are lineaments that dominate their entire surface. Those on Ceres' however, are more irregularly shaped and less distinct. On Ceres surface troughs seem to be relatively rare. However, they show similarities to troughs on Enceladus and Mercury, and could also be related to those on Europa and Ganymede. Domes are distributed over Ceres' entire surface and have a relatively regular shape. Analogous exist on Europa (relatively irregular or with halos) and Ganymede in the crater interiors.

  5. Performance of thermal conductivity probes for planetary applications

    Directory of Open Access Journals (Sweden)

    E. S. Hütter

    2012-05-01

    Full Text Available This work aims to contribute to the development of in situ instruments feasible for space application. Commercial as well as custom-made thermal sensors, based on the transient hot wire technique and suitable for direct measurement of the effective thermal conductivity of granular media, were tested for application under airless conditions. In order to check the ability of custom-made sensors to measure the thermal conductivity of planetary surface layers, detailed numerical simulations predicting the response of the different sensors have been performed. These simulations reveal that for investigations under high vacuum conditions (as they prevail, e.g. on the lunar surface, the derived thermal conductivity values can significantly depend on sensor geometry, axial heat flow, and the thermal contact between probe and surrounding material. Therefore, a careful calibration of each particular sensor is necessary in order to obtain reliable thermal conductivity measurements. The custom-made sensors presented in this work can serve as prototypes for payload to be flown on future planetary lander missions, in particular for airless bodies like the Moon, asteroids and comets, but also for Mars.

  6. Photometry of dark atmosphereless planetary bodies: an efficient numerical model

    Science.gov (United States)

    Wilkman, Olli; Muinonen, Karri; Peltoniemi, Jouni

    2015-12-01

    We present a scattering model for regolith-covered Solar System bodies. It can be used to compute the intensity of light scattered by a surface consisting of packed, mutually shadowing particles. Our intention is to provide a model in which other researchers can apply in studies of Solar System photometry. Our model is a Lommel-Seeliger type model, representing a medium composed of individual scatterers with small single-scattering albedo. This means that it is suitable for dark regolith surfaces such as the Moon and many classes of asteroids. Our model adds an additional term which takes into account the mutual shadowing between the scatterers. The scatterers can have an arbitrary phase function. We use a numerical ray-tracing simulation to compute the shadowing contribution. We present the model in a form which makes implementing it in existing software straightforward and fast. The model in practice is implemented as files containing pre-computed values of the surface reflection coefficient, which can be loaded into a user's program and used to compute the scattering in the desired viewing geometries. As the usage requires only a little simple arithmetic and a table look-up, it is as fast to use as common analytical models.

  7. Saltation-threshold model can explain aeolian features on low-air-density planetary bodies

    CERN Document Server

    Pähtz, Thomas

    2016-01-01

    Knowledge of the minimal fluid speeds at which sediment transport can be sustained is crucial for understanding whether underwater landscapes exposed to water streams and wind-blown loose planetary surfaces can be altered. It also tells us whether surface features, such as ripples and dunes, can evolve. Here, guided by state-of-the-art numerical simulations, we propose an analytical model predicting the minimal fluid speeds required to sustain sediment transport in a Newtonian fluid. The model results are consistent with measurements and estimates of the transport threshold in water and Earth's and Mars' atmospheres. Furthermore, it predicts reasonable wind speeds to sustain aeolian sediment transport ("saltation") on the low-air-density planetary bodies Triton, Pluto, and 67P/Churyumov-Gerasimenko (comet). This offers an explanation for possible aeolian surface features photographed on these bodies during space missions.

  8. Robotic Missions to Small Bodies and Their Potential Contributions to Human Exploration and Planetary Defense

    Science.gov (United States)

    Abell, Paul A.; Rivkin, Andrew S.

    2015-01-01

    Introduction: Robotic missions to small bodies will directly address aspects of NASA's Asteroid Initiative and will contribute to future human exploration and planetary defense. The NASA Asteroid Initiative is comprised of two major components: the Grand Challenge and the Asteroid Mission. The first component, the Grand Challenge, focuses on protecting Earth's population from asteroid impacts by detecting potentially hazardous objects with enough warning time to either prevent them from impacting the planet, or to implement civil defense procedures. The Asteroid Mission involves sending astronauts to study and sample a near-Earth asteroid (NEA) prior to conducting exploration missions of the Martian system, which includes Phobos and Deimos. The science and technical data obtained from robotic precursor missions that investigate the surface and interior physical characteristics of an object will help identify the pertinent physical properties that will maximize operational efficiency and reduce mission risk for both robotic assets and crew operating in close proximity to, or at the surface of, a small body. These data will help fill crucial strategic knowledge gaps (SKGs) concerning asteroid physical characteristics that are relevant for human exploration considerations at similar small body destinations. These data can also be applied for gaining an understanding of pertinent small body physical characteristics that would also be beneficial for formulating future impact mitigation procedures. Small Body Strategic Knowledge Gaps: For the past several years NASA has been interested in identifying the key SKGs related to future human destinations. These SKGs highlight the various unknowns and/or data gaps of targets that the science and engineering communities would like to have filled in prior to committing crews to explore the Solar System. An action team from the Small Bodies Assessment Group (SBAG) was formed specifically to identify the small body SKGs under the

  9. Extreme Environment Simulation - Current and New Capabilities to Simulate Venus and Other Planetary Bodies

    Science.gov (United States)

    Kremic, Tibor; Vento, Dan; Lalli, Nick; Palinski, Timothy

    2014-01-01

    Science, technology, and planetary mission communities have a growing interest in components and systems that are capable of working in extreme (high) temperature and pressure conditions. Terrestrial applications range from scientific research, aerospace, defense, automotive systems, energy storage and power distribution, deep mining and others. As the target environments get increasingly extreme, capabilities to develop and test the sensors and systems designed to operate in such environments will be required. An application of particular importance to the planetary science community is the ability for a robotic lander to survive on the Venus surface where pressures are nearly 100 times that of Earth and temperatures approach 500C. The scientific importance and relevance of Venus missions are stated in the current Planetary Decadal Survey. Further, several missions to Venus were proposed in the most recent Discovery call. Despite this interest, the ability to accurately simulate Venus conditions at a scale that can test and validate instruments and spacecraft systems and accurately simulate the Venus atmosphere has been lacking. This paper discusses and compares the capabilities that are known to exist within and outside the United States to simulate the extreme environmental conditions found in terrestrial or planetary surfaces including the Venus atmosphere and surface. The paper then focuses on discussing the recent additional capability found in the NASA Glenn Extreme Environment Rig (GEER). The GEER, located at the NASA Glenn Research Center in Cleveland, Ohio, is designed to simulate not only the temperature and pressure extremes described, but can also accurately reproduce the atmospheric compositions of bodies in the solar system including those with acidic and hazardous elements. GEER capabilities and characteristics are described along with operational considerations relevant to potential users. The paper presents initial operating results and concludes

  10. Theory for planetary exospheres: III. Radiation pressure effect on the Circular Restricted Three Body Problem and its implication on planetary atmospheres

    CERN Document Server

    Beth, Arnaud; Toublanc, Dominique; Dandouras, Iannis; Mazelle, Christian

    2015-01-01

    The planetary exospheres are poorly known in their outer parts, since the neutral densities are low compared with the instruments detection capabilities. The exospheric models are thus often the main source of information at such high altitudes. We present a new way to take into account analytically the additional effect of the stellar radiation pressure on planetary exospheres. In a series of papers, we present with an Hamiltonian approach the effect of the radiation pressure on dynamical trajectories, density profiles and escaping thermal flux. Our work is a generalization of the study by Bishop and Chamberlain (1989). In this third paper, we investigate the effect of the stellar radiation pressure on the Circular Restricted Three Body Problem (CR3BP), called also the photogravitational CR3BP, and its implication on the escape and the stability of planetary exospheres, especially for Hot Jupiters. In particular, we describe the transformation of the equipotentials and the location of the Lagrange points, an...

  11. How to approximate viscoelastic dynamic topographies of stagnant lid planetary bodies?

    Science.gov (United States)

    Dumoulin, Caroline; Čadek, Ondřej; Choblet, Gaël

    2013-04-01

    Planetary mantles are viscoelastic media. However, since numerical models of thermal convection in a viscoelastic spherical shell are still very challenging, most of the studies concerning dynamic topography of planetary surfaces generated by mantle convection use one of the following simplified rheological set-up: i) IVF (instantaneous viscous flow), ii) viscous body with a free surface, or iii) hybrid methods combining viscous deformation and elastic filtering of the topography. Justifications for the use of such approximations instead of a fully viscoelastic rheology have been made on the basis of simple tests with step-like viscosity structures, with small to moderate viscosity contrasts. However, because the rheology of planetary materials is thermally activated, the radial stratification of viscosity is more likely to be a continuous function of depth, and global viscosity contrasts might be very large. In our study, we systematically compare viscoelastic dynamic topography induced by an internal load to topographies generated by the three different simplified approaches listed above using a realistic viscosity profile for a stagnant lid associated to the lithosphere of a one plate planete. To this purpose, we compute response functions of surface topography and geoid using three different semi-spectral models that all include self-gravitation: a) a linear Maxwell body with a pseudo free upper surface, b) a viscous body with a pseudo free upper surface, and c) a viscous body with a free-slip condition at the surface. Results obtained with this last model (IVF) can then be filtered using the elastic thin shell approximation: the effective elastic thickness then corresponds to the elastic thickness that is needed to fit the viscoelastic topography with an elastic filtering of the IVF topography. We show that the effective elastic thickness varies strongly with the degree of the load, with the depth of the load, and with the duration of the loading. These

  12. How common are aeolian processes on planetary bodies with very thin atmospheres?

    Science.gov (United States)

    Pähtz, Thomas; Duran, Orencio

    2016-04-01

    Observations from the Voyager 2, New Horizons, and Rosetta missions indicate that aeolian surface features, such as ripples and dunes, do not only occur on the surfaces of Earth, Mars, and Titan, but seemingly also on the surfaces of planetary bodies with extremely thin atmospheres, such as Triton, Pluto, and the comet 67P/Churyumov-Gerasimenko. This is highly intriguing since the saltation-threshold wind shear velocities predicted for these bodies from standard saltation-threshold models are so large that wind erosion actually should not occur. Here, guided by coupled DEM/RANS numerical simulations of sediment transport in Newtonian fluid using the numerical model by Duran et al. (POF 24, 103306, 2012), we propose an analytical model based entirely on physical princinples that predicts the minimal fluid speeds required to sustain sediment transport in Newtonian fluid. The analytical model is consistent with measurements of the transport threshold in water and Earth's air and with a recent observational estimate of the threshold on Mars. When applied to Triton and Pluto, it predicts threshold wind shear velocities (ut) of about 1-3m/s, which is comparable to wind shear occurring during storms on Earth and Mars, for particles with diameters (d) within the range d ∈ [200,3000]μm. The minimal values (≈ 1m/s) are thereby predicted for surprisingly large particles with d ≈ 2000μm. When applied to 67P/Churyumov-Gerasimenko, the analytical model predicts threshold wind shear velocities that are fairly extreme (e.g., ut = 45m/s for d = 1cm), but nonetheless consistent with wind shear velocities estimated to occur on this comet. From our results, we conclude that surface-shaping wind erosion and thus the occurrence of aeolian surface features might be much more common on low-air-density planetary bodies than previously thought.

  13. Science Case for Planetary Exploration with Planetary CubeSats and SmallSats

    Science.gov (United States)

    Castillo-Rogez, Julie; Raymond, Carol; Jaumann, Ralf; Vane, Gregg; Baker, John

    2016-07-01

    Nano-spacecraft and especially CubeSats are emerging as viable low cost platforms for planetary exploration. Increasing miniaturization of instruments and processing performance enable smart and small packages capable of performing full investigations. While these platforms are limited in terms of payload and lifetime, their form factor and agility enable novel mission architectures and a refreshed relationship to risk. Leveraging a ride with a mothership to access far away destinations can significantly augment the mission science return at relatively low cost. Depending on resources, the mothership may carry several platforms and act as telecom relay for a distributed network or other forms of fractionated architectures. In Summer 2014 an international group of scientists, engineers, and technologists started a study to define investigations to be carried out by nano-spacecrafts. These applications flow down from key science priorities of interest across space agencies: understanding the origin and organization of the Solar system; characterization of planetary processes; assessment of the astrobiological significance of planetary bodies across the Solar system; and retirement of strategic knowledge gaps (SKGs) for Human exploration. This presentation will highlight applications that make the most of the novel architectures introduced by nano-spacecraft. Examples include the low cost reconnaissance of NEOs for science, planetary defense, resource assessment, and SKGs; in situ chemistry measurements (e.g., airless bodies and planetary atmospheres), geophysical network (e.g., magnetic field measurements), coordinated physical and chemical characterization of multiple icy satellites in a giant planet system; and scouting, i.e., risk assessment and site reconnaissance to prepare for close proximity observations of a mothership (e.g., prior to sampling). Acknowledgements: This study is sponsored by the International Academy of Astronautics (IAA). Part of this work is

  14. Fast and reliable symplectic integration for planetary system N-body problems

    Science.gov (United States)

    Hernandez, David M.

    2016-06-01

    We apply one of the exactly symplectic integrators, which we call HB15, of Hernandez & Bertschinger, along with the Kepler problem solver of Wisdom & Hernandez, to solve planetary system N-body problems. We compare the method to Wisdom-Holman (WH) methods in the MERCURY software package, the MERCURY switching integrator, and others and find HB15 to be the most efficient method or tied for the most efficient method in many cases. Unlike WH, HB15 solved N-body problems exhibiting close encounters with small, acceptable error, although frequent encounters slowed the code. Switching maps like MERCURY change between two methods and are not exactly symplectic. We carry out careful tests on their properties and suggest that they must be used with caution. We then use different integrators to solve a three-body problem consisting of a binary planet orbiting a star. For all tested tolerances and time steps, MERCURY unbinds the binary after 0 to 25 years. However, in the solutions of HB15, a time-symmetric HERMITE code, and a symplectic Yoshida method, the binary remains bound for >1000 years. The methods' solutions are qualitatively different, despite small errors in the first integrals in most cases. Several checks suggest that the qualitative binary behaviour of HB15's solution is correct. The Bulirsch-Stoer and Radau methods in the MERCURY package also unbind the binary before a time of 50 years, suggesting that this dynamical error is due to a MERCURY bug.

  15. N-body calculations of cluster growth in proto-planetary disks

    OpenAIRE

    Kempf, S.; Pfalzner, S.; Henning, Th.

    1999-01-01

    We investigated numerically the dust growth driven by Brownian motion in a proto-planetary disc around a solar-type young stellar object. This process is considered as the first stage in the transformation of the initially micron-sized solid particles to a planetary system. In contrast to earlier studies the growth was investigated at the small particle number densities typical for the conditions in a proto-planetary disc. Under such circumstances, the mean particle distance exceeds the typic...

  16. Mercury and other iron-rich planetary bodies as relics of inefficient accretion

    Science.gov (United States)

    Asphaug, E.; Reufer, A.

    2014-08-01

    Earth, Venus, Mars and asteroids such as Vesta and, perhaps, Lutetia have chondritic bulk compositions with massive silicate mantles surrounding iron cores. Anomalies include Mercury with its abundant metallic iron (about 70% by mass), the Moon with its small iron core, and metal-dominated asteroids. Although a giant impact with proto-Earth can explain the Moon's small core, a giant impact origin for Mercury is problematic. Such a scenario requires that proto-Mercury was blasted apart with far greater specific energy than required for lunar formation, yet retained substantial volatile elements and did not reaccrete its ejected mantle. Here we present numerical hydrocode simulations showing that proto-Mercury could have been stripped of its mantle in one or more high-speed collisions with a larger target planet that survived intact. A projectile that escapes the planet-colliding orbit in this hit-and-run scenario ultimately finds a permanent sink for its stripped mantle silicates. We show that if Mars and Mercury are derived from two planetary embryos that randomly avoided being accreted into a larger body, out of 20 original embryos (the rest having accreted into Venus and Earth), then it is statistically probable that one of those had its mantle stripped in one or two hit-and-run collisions. The same reasoning applies to pairwise accretion of planetesimals in the early Solar System, in which the relic bodies, which avoided becoming accreted, would be expected to have a wide diversity of compositions as a consequence of hit-and-run processes.

  17. Laboratory Simulated Impact Shock on Ices relevant to Planetary icy Bodies

    Science.gov (United States)

    Nna Mvondo, D.; Khare, B. N.; McKay, C. P.; Ishihara, T.

    2006-12-01

    Several icy satellites of the outer planets show impact cratering features and it is recognised that this process may have played a crucial role in the formation and evolution of icy bodies. The effect of impact by extraterrestrial objects into the surface is commonly related to physical changes. Most of the research applied to impacts on ices has been developed to study and understand the cratering formation process and their physical, geophysical characteristics. Chemical changes and synthesis occurring on icy planetary surfaces are generally explained by the influence of UV photons and high-energy charged particles on ices. Nonetheless, impact process onto ices could be a source of local or global endogenic process and could be especially advantageous as an efficient energy source for driving interesting chemistry. Impacts can ensure that icy surfaces are eventually exposed, for a limited period of time, to aqueous melt in impact craters and ejecta and one can imagine that impurities included in the ice may undergo hydrolysis and other reactions under such conditions. Upon impact, the kinetic energy of the bolide is transferred to the ground liberating a great deal of stress energy which could initiate in situ a diverse series of chemical reactions in the fracture zone beneath the crater (Borucki et al., 2002; Jones and Lewis, 1987). Here we present a new approach testing in laboratory the chemistry conducted by impacts into planetary ices and we report the first experimental results. We have irradiated with a powerful pulsed laser icy mixtures of pure water ices containing CO2, Na2CO3, CH3OH and CH3OH / (NH4)2SO4 at 77K. GC-MS and FTIR analyses show that hydrogen peroxide, carbon monoxide and methanol are formed in irradiated H2O / CO2 ices. Ice containing sodium carbonate generates under simulated impact CO and CO2 which are also produced in impacted H2O / CH3OH and H2O / CH3OH / (NH4)2SO4 ices. But, in both latter icy mixtures, methane and more complex

  18. Modeling Planetary System Formation with N-Body Simulations: Role of Gas Disk and Statistics Comparing to Observations

    OpenAIRE

    Liu, Huigen; Zhou, Ji-Lin; Wang, S.

    2009-01-01

    During the late stage of planet formation when Mars-size cores appear, interactions among planetary cores can excite their orbital eccentricities, speed their merges and thus sculpture the final architecture of planet systems. This series of work contributes to the final assembling of planet systems with N-body simulations, including the type I and II migration of planets, gas accretion of massive cores in a viscous disk. In this paper, the standard formulations of type I and II migrations ar...

  19. Earthbound Unmanned Autonomous Vehicles (UAVS) As Planetary Science Testbeds

    Science.gov (United States)

    Pieri, D. C.; Bland, G.; Diaz, J. A.; Fladeland, M. M.

    2014-12-01

    Recent advances in the technology of unmanned vehicles have greatly expanded the range of contemplated terrestrial operational environments for their use, including aerial, surface, and submarine. The advances have been most pronounced in the areas of autonomy, miniaturization, durability, standardization, and ease of operation, most notably (especially in the popular press) for airborne vehicles. Of course, for a wide range of planetary venues, autonomy at high cost of both money and risk, has always been a requirement. Most recently, missions to Mars have also featured an unprecedented degree of mobility. Combining the traditional planetary surface deployment operational and science imperatives with emerging, very accessible, and relatively economical small UAV platforms on Earth can provide flexible, rugged, self-directed, test-bed platforms for landed instruments and strategies that will ultimately be directed elsewhere, and, in the process, provide valuable earth science data. While the most direct transfer of technology from terrestrial to planetary venues is perhaps for bodies with atmospheres (and oceans), with appropriate technology and strategy accommodations, single and networked UAVs can be designed to operate on even airless bodies, under a variety of gravities. In this presentation, we present and use results and lessons learned from our recent earth-bound UAV volcano deployments, as well as our future plans for such, to conceptualize a range of planetary and small-body missions. We gratefully acknowledge the assistance of students and colleagues at our home institutions, and the government of Costa Rica, without which our UAV deployments would not have been possible. This work was carried out, in part, at the Jet Propulsion Laboratory of the California Institute of Technology under contract to NASA.

  20. Distant Secondary Craters from Lyot Crater, Mars, and Implications for Ages of Planetary Bodies

    Science.gov (United States)

    Robbins, S. J.; Hynek, B. M.

    2011-03-01

    We identified thousands of secondary craters in distinct clusters up to 5200 km from their primary crater, Lyot, on Mars. Their properties, relation to Lyot, and broader implications to secondary cratering and planetary ages will be discussed.

  1. Tier-Scalable Reconnaissance Missions For The Autonomous Exploration Of Planetary Bodies

    OpenAIRE

    Fink, Wolfgang; Dohm, James M.; Tarbell, Mark A.; Hare, Trent M.; Baker, Victor R.; Schulze-Makuch, Dirk; Furfaro, Roberto; Alberto G. Fairén; Ferré, Ty P.A.; Miyamoto, Hideaki; Komatsu, Goro; Mahaney, William C.

    2007-01-01

    A fundamentally new (scientific) reconnaissance mission concept, termed tier-scalable reconnaissance, for remote planetary (including Earth) atmospheric, surface and subsurface exploration recently has been devised that soon will replace the engineering and safety constrained mission designs of the past, allowing for optimal acquisition of geologic, paleohydrologic, paleoclimatic, and possible astrobiologic information of Venus, Mars, Europa, Ganymede, Titan, Enceladus, Triton, and other extr...

  2. Methanol incorporation in clathrate hydrates and the implications for oil and gas pipeline flow assurance and icy planetary bodies

    OpenAIRE

    Shin, Kyuchul; Udachin, Konstantin A.; Moudrakovski, Igor L.; Leek, Donald M.; Alavi, Saman; Ratcliffe, Christopher I.; Ripmeester, John A.

    2013-01-01

    One of the best-known uses of methanol is as antifreeze. Methanol is used in large quantities in industrial applications to prevent methane clathrate hydrate blockages from forming in oil and gas pipelines. Methanol is also assigned a major role as antifreeze in giving icy planetary bodies (e.g., Titan) a liquid subsurface ocean and/or an atmosphere containing significant quantities of methane. In this work, we reveal a previously unverified role for methanol as a guest in clathrate hydrate c...

  3. Development and testing of thermal sensors for planetary applications

    International Nuclear Information System (INIS)

    Various planetary bodies of our solar system which hold no or only a thin atmosphere arecovered by so-called regolith, a granular material of various grain size, which is mainly composed of crushed bedrock. Under the given conditions the dominant heat transfer mechanism between the body's interior and its surroundings is heat conduction. Thus the energy balanceof such a planetary body as a whole is controlled to a high extend by the effective thermal conductivity of the top surface layers. Because the local conditions have a strong influenceon the magnitude of this parameter, authentic values can best be obtained by in-situ measurements. Due to the limitations given for space missions and the harsh environmental conditions on site, direct investigations of the thermal conductivity of these regolith layersare challenging.The present work aims to contribute to the development of in-situ instruments feasible forspace application. Therefore commercial as well as custom made thermal sensors, basedon the transient hot wire technique and suitable for direct measurement of the effectivethermal conductivity of granular media, were tested for application under airless conditions. The investigated media range from compact specimen of well known thermal conductivityused for calibration of the sensors to various granular 'planetary analogue' materials of different shape and grain size. Measurements were performed under gas pressures rangingfrom 103 hPa down to about 10-5 hPa. It was found that for the inspected granular materialsthe given pressure decrease results in a decrease of the thermal conductivity by about twoorders of magnitude. Furthermore numerical simulations of the measurements with the different sensors have been done. Both, measurements and simulations, revealed that for investigations under high vacuum conditions special care has to be taken. (author)

  4. Regolith Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

    Science.gov (United States)

    Hogue, Michael D.; Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Rasky, Daniel J.

    2013-01-01

    This NIAC project investigated an innovative approach to provide heat shield protection to spacecraft after launch and prior to each EDL thus potentially realizing significant launch mass savings. Heat shields fabricated in situ can provide a thermal-protection system for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Regolith has extremely good insulating properties and the silicates it contains can be used in the fabrication and molding of thermal-protection materials. Such in situ developed heat shields have been suggested before by Lewis. Prior research efforts have shown that regolith properties can be compatible with very-high temperature resistance. Our project team is highly experienced in regolith processing and thermal protection systems (TPS). Routine access to space and return from any planetary surface requires dealing with heat loads experienced by the spacecraft during reentry. Our team addresses some of the key issues with the EDL of human-scale missions through a highly innovative investigation of heat shields that can be fabricated in space by using local resources on asteroids and moons. Most space missions are one-way trips, dedicated to placing an asset in space for economical or scientific gain. However, for human missions, a very-reliable heat-shield system is necessary to protect the crew from the intense heat experienced at very high entry velocities of approximately 11 km/s at approximately Mach 33 (Apollo). For a human mission to Mars, the return problem is even more difficult, with predicted velocities of up to 14 km/s, at approximately Mach 42 at the Earth-atmosphere entry. In addition to human return, it is very likely that future space-travel architecture will include returning cargo to the Earth, either for scientific purposes or for commercial reasons

  5. Regolith Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

    Science.gov (United States)

    Hogue, Michael D.; Meuller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Rasky, Daniel J.

    2012-01-01

    This NIAC project investigated an innovative approach to provide heat shield protection to spacecraft after launch and prior to each EDL thus potentially realizing significant launch mass savings. Heat shields fabricated in situ can provide a thermal-protection system for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Regolith has extremely good insulating properties and the silicates it contains can be used in the fabrication and molding of thermal-protection materials. Such in situ developed heat shields have been suggested before by Lewis. Prior research efforts have shown that regolith properties can be compatible with very-high temperature resistance. Our project team is highly experienced in regolith processing and thermal protection systems (TPS). Routine access to space and return from any planetary surface requires dealing with heat loads experienced by the spacecraft during reentry. Our team addresses some of the key issues with the EDL of human-scale missions through a highly innovative investigation of heat shields that can be fabricated in space by using local resources on asteroids and moons. Most space missions are one-way trips, dedicated to placing an asset in space for economical or scientific gain. However, for human missions, a very-reliable heat-shield system is necessary to protect the crew from the intense heat experienced at very high entry velocities of approximately 11 km/s at approximately Mach 33 (Apollo). For a human mission to Mars, the return problem is even more difficult, with predicted velocities of up to 14 km/s, at approximately Mach 42 at the Earth-atmosphere entry. In addition to human return, it is very likely that future space-travel architecture will include returning cargo to the Earth, either for scientific purposes or for commercial reasons

  6. Maintenance of Surface Current Balance by Field-Aligned Thermoelectric Currents at Astronomical Bodies: Cassini at Rhea

    Science.gov (United States)

    Teolis, B. D.

    2014-12-01

    Cassini spacecraft magnetic field data at Saturn's moon Rhea reveal a field-aligned electric current system in the flux tube, which forms to satisfy the requirement to balance ion and electron currents on the moon's sharp surface. Unlike induction currents at bodies surrounded by significant atmospheres, Rhea's flux tube current system is not driven by motion through the plasma, but rather thermoelectrically, by heat flow into the object. In addition to Rhea, the requirements for the current system are easily satisfied at many plasma absorbing bodies: (1) a difference of average ion and electron gyroradii radii, and (2) a "sharp" body of any size, i.e., without a significant thick atmosphere. This type of current system is therefore expected to occur generally, e.g. at other airless planetary satellites, asteroids, and even spacecraft; and accordingly, represents a fundamental aspect of the physics of the interaction of astrophysical objects with space plasmas.

  7. An N-body Integrator for Gravitating Planetary Rings, and the Outer Edge of Saturn's B Ring

    CERN Document Server

    Hahn, Joseph M

    2013-01-01

    A new symplectic N-body integrator is introduced, one designed to calculate the global 360 degree evolution of a self-gravitating planetary ring that is in orbit about an oblate planet. This freely-available code is called epi_int, and it is distinct from other such codes in its use of streamlines to calculate the effects of ring self-gravity. The great advantage of this approach is that the perturbing forces arise from smooth wires of ring matter rather than discreet particles, so there is very little gravitational scattering and so only a modest number of particles are needed to simulate, say, the scalloped edge of a resonantly confined ring or the propagation of spiral density waves. The code is applied to the outer edge of Saturn's B ring, and a comparison of Cassini measurements of the ring's forced response to simulations of Mimas' resonant perturbations reveals that the B ring's surface density at its outer edge is 195+-60 gm/cm^2 which, if the same everywhere across the ring would mean that the B ring...

  8. Three body resonances in close orbiting planetary systems: Tidal dissipation and orbital evolution

    CERN Document Server

    Papaloizou, John C B

    2014-01-01

    We study the orbital evolution of a three planet system with masses in the super-Earth regime resulting from the action of tides on the planets induced by the central star which cause orbital circularization. We consider systems either in or near to a three body commensurability for which adjacent pairs of planets are in a first order commensurability. We develop a simple analytic solution, derived from a time averaged set of equations, that describes the expansion of the system away from strict commensurability as a function of time, once a state where relevant resonant angles undergo small amplitude librations has been attained. We perform numerical simulations that show the attainment of such resonant states focusing on the Kepler 60 system. The results of the simulations confirm many of the scalings predicted by the appropriate analytic solution. We go on to indicate how the results can be applied to put constraints on the amount of tidal dissipation that has occurred in the system. For example, if the sy...

  9. Mothership - Affordable Exploration of Planetary Bodies through Individual Nano-Sats and Swarms

    Science.gov (United States)

    DiCorcia, James D.; Ernst, Sebastian M.; Grace, J. Mike; Gump, David P.; Lewis, John S.; Foulds, Craig F.; Faber, Daniel R.

    2015-04-01

    One concept to enable broad participation in the scientific exploration of small bodies is the Mothership mission architecture which delivers third-party nano-sats, experiments, and sensors to a near Earth asteroid or comet. Deep Space Industries' Mothership service includes delivery of nano-sats, communication to Earth, and visuals of the asteroid surface and surrounding area. It allows researchers to house their instruments in a low-cost nano-sat platform that does not require the high-performance propulsion or deep space communication capabilities that otherwise would be required for a solo asteroid mission. This enables organizations with relatively low operating budgets to closely examine an asteroid with highly specialized sensors of their own choosing, while the nano-sats can be built or commissioned by a variety of smaller institutions, companies, or agencies. In addition, the Mothership and its deployed nano-sats can offer a platform for instruments which need to be distributed over multiple spacecraft. The Mothership is designed to carry 10 to 12 nano-sats, based upon a variation of the Cubesat standard, with some flexibility on the specific geometry. The Deep Space Nano-Sat reference design is a 14.5 cm cube, which accomodates the same volume as a traditional 3U Cubesat. This design was found to be more favorable for deep space due to its thermal characteristics. The CubeSat standard was originally designed with operations in low Earth orbit in mind. By deliberately breaking the standard, Deep Space Nano-Sats offer better performance with less chance of a critical malfunction in the more hostile deep space environment. The first mission can launch as early as Q4 2017, with subsequent, regular launches through the 2020's.

  10. The Highland Terrain Hopper: a new locomotion system for exploration of Mars and other low-gravity planetary bodies

    Science.gov (United States)

    Gurgurewicz, Joanna; Grygorczuk, Jerzy; Wisniewski, Lukasz; Mege, Daniel; Rickman, Hans

    Field geoscientists need to collect three-dimensional data in order characterise the lithologic succession and structure of terrains, reconstruct their evolution, and eventually reveal the history of a portion of the planet. This is achieved by walking up and down mountains and valleys, conducting and interpreting geological and geophysical traverses, and reading measures made at station located at key sites on mountain peaks or rocky promontories. These activities have been denied to conventional planetary exploration rovers because engineering constraints for landing are strong, especially in terms of allowed terrain roughness and slopes. There are few limitations in the type of scientific payload conventional exploration rovers can carry, from geology and geophysics to geochemistry and exobiology. They lack two skills, however: the ability of working on rugged or unstable terrain, like in canyons and mountains, and on solid bodies having gravity too low for the friction between the wheels and the ground to generate robot displacement. ASTRONIKA Ltd. and the Space Research Centre of the Polish Academy of Sciences are designing Galago, the Highland Terrain Hopper, a small (Ø~50-100 cm), light (5-10 kg), and robust locomotion system, which addresses the challenge of accessing most areas on low-gravity planetary body for performing scientific observations and measurements, alone or as part of a commando. Galago is symmetric and can jump accurately to a height of 4.5 m on Mars, 9 m on the Moon, and much more on Phobos and other small bodies. For one Galago, a nominal horizontal travel distance of 5 km (1000 jumps) is currently planned with the considered energy source, a battery reloaded by solar panels. Galago may assist other types of robots, or humans, in accessing difficult terrain, or even replace them for specific measurements or campaigning. Its three independent legs make possible several types of motions: accurate jumping (to any place identified in advance

  11. Regolith Derived Heat Shield for a Planetary Body Entry and Descent System with In-Situ Fabrication Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High-mass planetary surface access is one of NASA’s Grand Challenges involving entry, descent and landing (EDL). During the entry and descent phase,...

  12. Europlanet Research Infrastructure: Planetary Simulation Facilities

    Science.gov (United States)

    Davies, G. R.; Mason, N. J.; Green, S.; Gómez, F.; Prieto, O.; Helbert, J.; Colangeli, L.; Srama, R.; Grande, M.; Merrison, J.

    2008-09-01

    physical properties of ice samples formed under planetary conditions to assess how rheology varies with pressure and temperature and grain size to gain a far better understanding of how tectonics may operate on icy moons. Hot planetary surfaces simulation chamber at DLR The planetary simulation chamber is to study the behaviour of planetary analogue materials on the surface of hot (airless) bodies in the solar system. Samples can be heated up to temperatures of 500°C simulating conditions found on the surface of Mercury and Venus. This enables highly accurate thermal emission measurements using the integrated infrared spectrometer and calibrated sources. Thermal gradients can be applied to samples to simulate diurnal thermal cycles and examine thermal stresses in materials. The chamber can be placed under vacuum or purged with gas. In addition, to the high temperature chamber a number of further planetary simulation chambers are available equipped with LIBS and Raman-spectroscopy equipment. Dust analogue simulation chamber at INAF/OACN This facility produces and characterises dust analogues (arc discharge, laser ablation, grinding of minerals, ices) in a variety of simulation chambers under variable pressure (10-6 - 10-3 mbar), temperature (80 - 330 K) and gas composition. Dust and analogues are characterised by a variety of Spectroscopic (absorption, transmission, diffuse-specular reflectance) and imaging techniques (SEM) and can be subjected to thermal annealing, ion bombardment and UV irradiation. Dust accelerator facility at Max Planck Institüt Nuclear Physics, Heidelberg. This facility allows the investigation of hypervelocity dust impacts onto various materials. Dust grain materials from nano to micron sizes are accelerated using a 2 MV Vande- Graaff to velocities between 1 and 60 km/s comparable to the planetary rings of the giant gas planets and impact ejecta processes on the surface of small bodies (asteroids, comets) as well as moons and planetary surfaces

  13. Planetary Rings

    Science.gov (United States)

    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.

  14. AN N-BODY INTEGRATOR FOR GRAVITATING PLANETARY RINGS, AND THE OUTER EDGE OF SATURN'S B RING

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Joseph M. [Space Science Institute, c/o Center for Space Research, University of Texas at Austin, 3925 West Braker Lane, Suite 200, Austin, TX 78759-5378 (United States); Spitale, Joseph N., E-mail: jhahn@spacescience.org, E-mail: jnspitale@psi.edu [Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395 (United States)

    2013-08-01

    A new symplectic N-body integrator is introduced, one designed to calculate the global 360 Degree-Sign evolution of a self-gravitating planetary ring that is in orbit about an oblate planet. This freely available code is called epi{sub i}nt, and it is distinct from other such codes in its use of streamlines to calculate the effects of ring self-gravity. The great advantage of this approach is that the perturbing forces arise from smooth wires of ring matter rather than discreet particles, so there is very little gravitational scattering and so only a modest number of particles are needed to simulate, say, the scalloped edge of a resonantly confined ring or the propagation of spiral density waves. The code is applied to the outer edge of Saturn's B ring, and a comparison of Cassini measurements of the ring's forced response to simulations of Mimas's resonant perturbations reveals that the B ring's surface density at its outer edge is {sigma}{sub 0} = 195 {+-} 60 g cm{sup -2}, which, if the same everywhere across the ring, would mean that the B ring's mass is about 90% of Mimas's mass. Cassini observations show that the B ring-edge has several free normal modes, which are long-lived disturbances of the ring-edge that are not driven by any known satellite resonances. Although the mechanism that excites or sustains these normal modes is unknown, we can plant such a disturbance at a simulated ring's edge and find that these modes persist without any damping for more than {approx}10{sup 5} orbits or {approx}100 yr despite the simulated ring's viscosity {nu}{sub s} = 100 cm{sup 2} s{sup -1}. These simulations also indicate that impulsive disturbances at a ring can excite long-lived normal modes, which suggests that an impact in the recent past by perhaps a cloud of cometary debris might have excited these disturbances, which are quite common to many of Saturn's sharp-edged rings.

  15. Probing Planetary Bodies for Subsurface Volatiles: GEANT4 Models of Gamma Ray, Fast, Epithermal, and Thermal Neutron Response to Active Neutron Illumination

    Science.gov (United States)

    Chin, G.; Sagdeev, R.; Su, J. J.; Murray, J.

    2014-12-01

    Using an active source of neutrons as an in situ probe of a planetary body has proven to be a powerful tool to extract information about the presence, abundance, and location of subsurface volatiles without the need for drilling. The Dynamic Albedo of Neutrons (DAN) instrument on Curiosity is an example of such an instrument and is designed to detect the location and abundance of hydrogen within the top 50 cm of the Martian surface. DAN works by sending a pulse of neutrons towards the ground beneath the rover and detecting the reflected neutrons. The intensity and time of arrival of the reflection depends on the proportion of water, while the time the pulse takes to reach the detector is a function of the depth at which the water is located. Similar instruments can also be effective probes at the polar-regions of the Moon or on asteroids as a way of detecting sequestered volatiles. We present the results of GEANT4 particle simulation models of gamma ray, fast, epithermal, and thermal neutron responses to active neutron illumination. The results are parameterized by hydrogen abundance, stratification and depth of volatile layers, versus the distribution of neutron and gamma ray energy reflections. Models will be presented to approximate Martian, lunar, and asteroid environments and would be useful tools to assess utility for future NASA exploration missions to these types of planetary bodies.

  16. Photoelectric dust levitation around airless bodies revised using realistic photoelectron velocity distributions

    Science.gov (United States)

    Senshu, H.; Kimura, H.; Yamamoto, T.; Wada, K.; Kobayashi, M.; Namiki, N.; Matsui, T.

    2015-10-01

    The velocity distribution function of photoelectrons from a surface exposed to solar UV radiation is fundamental to the electrostatic status of the surface. There is one and only one laboratory measurement of photoelectron emission from astronomically relevant material, but the energy distribution function was measured only in the emission angle from the normal to the surface of 0 to about π / 4. Therefore, the measured distribution is not directly usable to estimate the vertical structure of a photoelectric sheath above the surface. In this study, we develop a new analytical method to calculate an angle-resolved velocity distribution function of photoelectrons from the laboratory measurement data. We find that the photoelectric current and yield for lunar surface fines measured in a laboratory have been underestimated by a factor of two. We apply our new energy distribution function of photoelectrons to model the formation of photoelectric sheath above the surface of asteroid 433 Eros. Our model shows that a 0.1 μm-radius dust grain can librate above the surface of asteroid 433 Eros regardless of its launching velocity. In addition, a 0.5 μm grain can hover over the surface if the grain was launched at a velocity slower than 0.4 m/s, which is a more stringent condition for levitation than previous studies. However, a lack of high-energy data on the photoelectron energy distribution above 6 eV prevents us from firmly placing a constraint on the levitation condition.

  17. An explanation of forms of planetary orbits and estimation of angular shift of the Mercury' perihelion using the statistical theory of gravitating spheroidal bodies

    Science.gov (United States)

    Krot, A. M.

    2013-09-01

    This work develops a statistical theory of gravitating spheroidal bodies to calculate the orbits of planets and explore forms of planetary orbits with regard to the Alfvén oscillating force [1] in the Solar system and other exoplanetary systems. The statistical theory of formation of gravitating spheroidal bodies has been proposed in [2]-[5]. Starting the conception for forming a spheroidal body inside a gas-dust protoplanetary nebula, this theory solves the problem of gravitational condensation of a gas-dust protoplanetary cloud with a view to planetary formation in its own gravitational field [3] as well as derives a new law of the Solar system planetary distances which generalizes the wellknown laws [2], [3]. This work also explains an origin of the Alfvén oscillating force modifying forms of planetary orbits within the framework of the statistical theory of gravitating spheroidal bodies [5]. Due to the Alfvén oscillating force moving solid bodies in a distant zone of a rotating spheroidal body have elliptic trajectories. It means that orbits for the enough remote planets from the Sun in Solar system are described by ellipses with focus in the origin of coordinates and with small eccentricities. The nearby planet to Sun named Mercury has more complex trajectory. Namely, in case of Mercury the angular displacement of a Newtonian ellipse is observed during its one rotation on an orbit, i.e. a regular (century) shift of the perihelion of Mercury' orbit occurs. According to the statistical theory of gravitating spheroidal bodies [2]-[5] under the usage of laws of celestial mechanics in conformity to cosmogonic bodies (especially, to stars) it is necessary to take into account an extended substance called a stellar corona. In this connection the stellar corona can be described by means of model of rotating and gravitating spheroidal body [5]. Moreover, the parameter of gravitational compression α of a spheroidal body (describing the Sun, in particular) has been

  18. From Science Reserves to Sustainable Multiple Uses beyond Earth orbit: Evaluating Issues on the Path towards Balanced Environmental Management on Planetary Bodies

    Science.gov (United States)

    Race, Margaret

    Over the past five decades, our understanding of space beyond Earth orbit has been shaped by a succession of mainly robotic missions whose technologies have enabled scientists to answer diverse science questions about celestial bodies across the solar system. For all that time, exploration has been guided by planetary protection policies and principles promulgated by COSPAR and based on provisions in Article IX of the Outer Space Treaty of 1967. Over time, implementation of the various COSPAR planetary protection policies have sought to avoid harmful forward and backward contamination in order to ensure the integrity of science findings, guide activities on different celestial bodies, and appropriately protect Earth whenever extraterrestrial materials have been returned. The recent increased interest in extending both human missions and commercial activities beyond Earth orbit have prompted discussions in various quarters about the need for updating policies and guidelines to ensure responsible, balanced space exploration and use by all parties, regardless whether activities are undertaken by governmental or non-governmental entities. Already, numerous researchers and workgroups have suggested a range of different ways to manage activities on celestial environments (e.g, wilderness parks, exclusion zones, special regions, claims, national research bases, environmental impact assessments, etc.). While the suggestions are useful in thinking about how to manage future space activities, they are not based on any systematically applied or commonly accepted criteria (scientific or otherwise). In addition, they are borrowed from terrestrial approaches for environmental protection, which may or may not have direct applications to space environments. As noted in a recent COSPAR-PEX workshop (GWU 2012), there are no clear definitions of issues such as harmful contamination, the environment to be protected, or what are considered reasonable activity or impacts for particular

  19. Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System

    CERN Document Server

    Lomax, Jamie R; Grady, Carol A; McElwain, Michael W; Hashimoto, Jun; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Okamoto, Yoshiko K; Fukagawa, Misato; Abe, Lyu; Brandner, Wolfgang; Brandt, Timothy D; Carson, Joseph C; Currie, Thayne M; Egner, Sebastian; Feldt, Markus; Goto, Miwa; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko S; Henning, Thomas; Hodapp, Klaus W; Inoue, Akio; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R; Kuzuhara, Masayuki; Kwon, Jungmi; Matsuo, Taro; Mayama, Satoshi; Miyama, Shoken; Momose, Munetake; Morino, Jun-Ichi; Moro-Martin, Amaya; Nishimura, Tetsuo; Pyo, Tae-Soo; Schneider, Glenn H; Serabyn, Eugene; Sitko, Michael L; Suenaga, Takuya; Suto, Hiroshi; Suzuki, Ryuji; Takahashi, Yasuhiro H; Takami, Michihiro; Takato, Naruhisa; Terada, Hiroshi; Thalmann, Christian; Tomono, Daigo; Turner, Edwin L; Watanabe, Makoto; Yamada, Toru; Takami, Hideki; Usuda, Tomonori; Tamura, Motohide

    2016-01-01

    We present new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously model the system's SED and H-band polarized intensity imagery. We find that a disk-dominated model, as opposed to one that is envelope dominated, can plausibly reproduce AB Aur's SED and near-IR imagery. This is consistent with previous modeling attempts presented in the literature and supports the idea that at least a subset of AB Aur's spirals originate within the disk. In light of this, we also analyzed the movement of spiral structures in multi-epoch H-band total light and polarized intensity imagery of the disk. We detect no significant rotation or change in spatial location of the spiral structures in these data, which span a 5.8 year baseline. If such structures are caused by disk-planet interactions, the lack of observed rotation constrains the location of the orbit of planetary perturbers to be >47 AU.

  20. Linking long-term planetary $N$-body simulations with periodic orbits: application to white dwarf pollution

    CERN Document Server

    Antoniadou, Kyriaki I

    2016-01-01

    Mounting discoveries of debris discs orbiting newly-formed stars and white dwarfs (WDs) showcase the importance of modeling the long-term evolution of small bodies in exosystems. WD debris discs are in particular thought to form from very long-term (0.1-5.0 Gyr) instability between planets and asteroids. However, the time-consuming nature of $N$-body integrators which accurately simulate motion over Gyrs necessitates a judicious choice of initial conditions. The analytical tools known as \\textit{periodic orbits} can circumvent the guesswork. Here, we begin a comprehensive analysis directly linking periodic orbits with $N$-body integration outcomes with an extensive exploration of the planar circular restricted three-body problem (CRTBP) with an outer planet and inner asteroid near or inside of the $2$:$1$ mean motion resonance. We run nearly 1000 focused simulations for the entire age of the Universe (14 Gyr) with initial conditions mapped to the phase space locations surrounding the unstable and stable perio...

  1. Linking long-term planetary N-body simulations with periodic orbits: application to white dwarf pollution

    Science.gov (United States)

    Antoniadou, Kyriaki I.; Veras, Dimitri

    2016-09-01

    Mounting discoveries of debris discs orbiting newly-formed stars and white dwarfs (WDs) showcase the importance of modeling the long-term evolution of small bodies in exosystems. WD debris discs are in particular thought to form from very long-term (0.1-5.0 Gyr) instability between planets and asteroids. However, the time-consuming nature of N-body integrators which accurately simulate motion over Gyrs necessitates a judicious choice of initial conditions. The analytical tools known as periodic orbits can circumvent the guesswork. Here, we begin a comprehensive analysis directly linking periodic orbits with N-body integration outcomes with an extensive exploration of the planar circular restricted three-body problem (CRTBP) with an outer planet and inner asteroid near or inside of the 2:1 mean motion resonance. We run nearly 1000 focused simulations for the entire age of the Universe (14 Gyr) with initial conditions mapped to the phase space locations surrounding the unstable and stable periodic orbits for that commensurability. In none of our simulations did the planar CRTBP architecture yield a long-timescale (≳ 0.25% of the age of the Universe) asteroid-star collision. The pericentre distance of asteroids which survived beyond this timescale (≈35 Myr) varied by at most about 60%. These results help affirm that collisions occur too quickly to explain WD pollution in the planar CRTBP 2:1 regime, and highlight the need for further periodic orbit studies with the eccentric and inclined TBP architectures and other significant orbital period commensurabilities.

  2. Maskelynite in asteroidal, lunar and planetary basaltic meteorites: An indicator of shock pressure during impact ejection from their parent bodies

    Science.gov (United States)

    Rubin, Alan E.

    2015-09-01

    Maskelynite is a diaplectic glass that forms from plagioclase at shock pressures of ∼20-30 GPa, depending on the Ca concentration. The proportion of maskelynite-rich samples in a basaltic meteorite group correlates with the parent-body escape velocity and serves as a shock indicator of launching conditions. For eucrites (basalts widely presumed to be from Vesta; vesc = 0.36 km s-1), ∼5% of the samples are maskelynite rich. For the Moon (vesc = 2.38 km s-1), ∼30% of basaltic meteorites are maskelynite rich. For Mars (vesc = 5.03 km s-1), ∼93% of basaltic meteorites are maskelynite rich. In contrast, literature data show that maskelynite is rare (∼1%) among mare basalts and basaltic fragments in Apollo 11, 12, 15 and 17 soils (which were never ejected from the Moon). Angrites are unbrecciated basaltic meteorites that are maskelynite free; they were ejected at low-to-moderate shock pressures from an asteroid smaller than Vesta. Because most impacts that eject materials from a large (⩾100 km) parent body are barely energetic enough to do that, a collision that has little more than the threshold energy required to eject a sample from Vesta will not be able to eject identical samples from the Moon or Mars. There must have been relatively few impacts, if any, that launched eucrites off their parent body that also imparted shock pressures of ∼20-30 GPa in the ejected rocks. More-energetic impacts were required to launch basalts off the Moon and Mars. On average, Vesta ejecta were subjected to lower shock pressures than lunar ejecta, and lunar ejecta were subjected to lower shock pressures than martian ejecta. H and LL ordinary chondrites have low percentages of shock-stage S5 maskelynite-bearing samples (∼1% and ∼4%, respectively), probably reflecting shock processes experienced by these rocks on their parent asteroids. In contrast, L chondrites have a relatively high proportion of samples containing maskelynite (∼11%), most likely a result of

  3. Planetary Magnetism

    Science.gov (United States)

    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.

  4. Non-planetary Science from Planetary Missions

    Science.gov (United States)

    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

  5. Planetary geosciences, 1989-1990

    Science.gov (United States)

    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.

  6. Planetary Society

    Science.gov (United States)

    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...

  7. Stability of inner planetary systems

    Science.gov (United States)

    Szebehely, V.

    1979-01-01

    The stability of inner planetary systems with arbitrary mass ratios is studied on the basis of the model of the plane restricted three-body problem. A quantitative stability criterion is obtained in terms of the difference between the critical value of the Jacobi constants (at which bifurcation can occur) and the critical value corresponding to a planetary orbit. An orbit is stable if it cannot leave a region that contains only the larger central body (Hill). For small values of the mass parameter, the maximum dimensionless radius of a Hill-stable orbit is 1 minus 2.4 times the cube root of the mass parameter.

  8. Secular Resonances In Planetary Systems

    Science.gov (United States)

    Malhotra, Renu

    2006-06-01

    Secular effects introduce very low frequencies in planetary systems. The consequences are quite varied. They include mundane effects on the planetary ephemerides and on Earthly seasons, but also more esoteric effects such as apsidal alignment or anti-alignment, fine-splitting of mean motion resonances, broadening of chaotic zones, and dramatic orbital instabilities. Secular effects may shape the overall architecture of mature planetary systems by determining the long term stability of major and minor planetary bodies. This talk will be partly tutorial and partly a review of secular resonance phenomena here in the solar system and elsewhere in extra-solar systems. I acknowledge research support from NASA-Origins of Solar Systems and NASA-Outer Planets research programs.

  9. Formation of planetary systems

    International Nuclear Information System (INIS)

    It seemed appropriate to devote the 1980 School to the origin of the solar system and more particularly to the formation of planetary systems (dynamic accretion processes, small bodies, planetary rings, etc...) and to the physics and chemistry of planetary interiors, surface and atmospheres (physical and chemical constraints associated with their formation). This Summer School enabled both young researchers and hard-nosed scientists, gathered together in idyllic surroundings, to hold numerous discussions, to lay the foundations for future cooperation, to acquire an excellent basic understanding, and to make many useful contacts. This volume reflects the lectures and presentations that were delivered in this Summer School setting. It is aimed at both advanced students and research workers wishing to specialize in planetology. Every effort has been made to give an overview of the basic knowledge required in order to gain a better understanding of the origin of the solar system. Each article has been revised by one or two referees whom I would like to thank for their assistance. Between the end of the School in August 1980 and the publication of this volume in 1982, the Voyager probes have returned a wealth of useful information. Some preliminary results have been included for completeness

  10. Blue Marble Matches: Using Earth for Planetary Comparisons

    Science.gov (United States)

    Graff, Paige Valderrama

    2009-01-01

    Goal: This activity is designed to introduce students to geologic processes on Earth and model how scientists use Earth to gain a better understanding of other planetary bodies in the solar system. Objectives: Students will: 1. Identify common descriptor characteristics used by scientists to describe geologic features in images. 2. Identify geologic features and how they form on Earth. 3. Create a list of defining/distinguishing characteristics of geologic features 4. Identify geologic features in images of other planetary bodies. 5. List observations and interpretations about planetary body comparisons. 6. Create summary statements about planetary body comparisons.

  11. Origin of the eclogitic clasts with graphite-bearing and graphite-free lithologies in the Northwest Africa 801 (CR2) chondrite: Possible origin from a Moon-sized planetary body inferred from chemistry, oxygen isotopes and REE abundances

    Science.gov (United States)

    Hiyagon, H.; Sugiura, N.; Kita, N. T.; Kimura, M.; Morishita, Y.; Takehana, Y.

    2016-08-01

    In order to clarify the origin of the eclogitic clasts found in the NWA801 (CR2) chondrite (Kimura et al., 2013), especially, that of the high pressure and temperature (P-T) condition (∼3 GPa and ∼1000 °C), we conducted ion microprobe analyses of oxygen isotopes and rare earth element (REE) abundances in the clasts. Oxygen isotopic compositions of the graphite-bearing lithology (GBL) and graphite-free lithology (GFL) show a slope ∼0.6 correlation slightly below the CR-CH-CB chondrites field in the O three-isotope-diagram, with a large variation for the former and almost homogeneous composition for the latter. The average REE abundances of the two lithologies show almost unfractionated patterns. Based on these newly obtained data, as well as mineralogical observations, bulk chemistry, and considerations about diffusion timescales for various elements, we discuss in detail the formation history of the clasts. Consistency of the geothermobarometers used by Kimura et al. (2013), suggesting equilibration of various elements among different mineral pairs, provides a strong constraint for the duration of the high P-T condition. We suggest that the high P-T condition lasted 102-103 years. This clearly precludes a shock high pressure (HP) model, and hence, strongly supports a static HP model. A static HP model requires a Moon-sized planetary body of ∼1500 km in radius. Furthermore, it implies two successive violent collisions, first at the formation of the large planetary body, when the clasts were placed its deep interior, and second, at the disruption of the large planetary body, when the clasts were expelled out of the parent body and later on transported to the accretion region of the CR chondrites. We also discuss possible origin of O isotopic variations in GBL, and presence/absence of graphite in GBL/GFL, respectively, in relation to smelting possibly occurred during the igneous process(es) which formed the two lithologies. Finally we present a possible

  12. Young Planetary disks

    Science.gov (United States)

    Lecavelier Des Etangs, A.

    2007-07-01

    The present review focuses on UV observations of young planetary disks and consequently mostly on the gaseous content of those disks. Few examples are taken to illustrate the capability of the UV observatories to scrutinize in detail the gas content of low density circumstellar disks if they are seen edge-on or nearly edge-on. For instance, in the case of HD100546, FUSE observations re- vealed signatures of outflow and infall in the disk caused by interaction of the stellar magnetosphere with the circumstellar disk. Observations of numerous absorption lines from H2 around young stars give constrains on the gas temper- ature and density, and physical size of the absorbing layer. In the case of T-Tauri stars and one brown dwarf, emissions from exited H2 have been detected. In the case of Beta Pictoris, the observation of CO in the UV and search for H2 with FUSE demonstrated that the evaporation of frozen bodies like comets must produce the CO seen in the disk. Extensive observations of spectral variability of Beta Pictoris are now interpreted by extrasolar comets evaporating in the vicinity of the central star of this young planetary system.

  13. Preliminary Broadband Measurements of Dielectric Permittivity of Planetary Regolith Analog Materials Using a Coaxial Airline

    Science.gov (United States)

    Boivin, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2014-12-01

    When considering radar observations of airless bodies containing regolith, the radar backscatter coefficient is dependent upon the complex dielectric permittivity of the regolith materials. In many current applications of imaging radar data, uncertainty in the dielectric permittivity precludes quantitative estimates of such important parameters as regolith thickness and depth to buried features (e.g., lava flows on the Aristarchus Plateau on the Moon and the flows that surround the Quetzalpetlatl Corona on Venus). For asteroids, radar is an important tool for detecting and characterizing regoliths. Many previous measurements of the real and/or complex parts of the dielectric permittivity have been made, particularly for the Moon (on both Apollo samples and regolith analogues). However, no studies to date have systematically explored the relationship between permittivity and the various mineralogical components such as presence of FeO and TiO2. For lunar materials, the presence of the mineral ilmenite (FeTiO3), which contains equal portions FeO and TiO2, is thought to be the dominant factor controlling the loss tangent (tanδ, the ratio of the imaginary and real components of the dielectric permittivity). Ilmenite, however, is not the only mineral to contain iron in the lunar soil and our understanding of the effect of iron on the loss tangent is insufficient. Beyond the Moon, little is known about the effects on permittivity of carbonaceous materials. This is particularly relevant for missions to asteroids, such as the OSIRIS-REx mission to (101955) Bennu, a carbonaceous asteroid whose regolith composition is largely unknown. Here we present preliminary broadband (300 Mhz to 14 GHz) measurements on materials intended as planetary regolith analogs. Our ultimate goal is to establish a database of the effects of a wide range mineralogical components on dielectric permittivity, in support of the OSIRIS REx mission and ongoing Earth-based radar investigation of the Moon

  14. Planetary Data System (PDS)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Planetary Data System (PDS) is an archive of data products from NASA planetary missions, which is sponsored by NASA's Science Mission Directorate. We actively...

  15. Planetary Landscape Geography

    Science.gov (United States)

    Hargitai, H.

    INTRODUCTION Landscape is one of the most often used category in physical ge- ography. The term "landshap" was introduced by Dutch painters in the 15-16th cen- tury. [1] The elements that build up a landscape (or environment) on Earth consists of natural (biogenic and abiogenic - lithologic, atmospheric, hydrologic) and artificial (antropogenic) factors. Landscape is a complex system of these different elements. The same lithology makes different landscapes under different climatic conditions. If the same conditions are present, the same landscape type will appear. Landscapes build up a hierarchic system and cover the whole surface. On Earth, landscapes can be classified and qualified according to their characteristics: relief forms (morphology), and its potential economic value. Aesthetic and subjective parameters can also be considered. Using the data from landers and data from orbiters we can now classify planetary landscapes (these can be used as geologic mapping units as well). By looking at a unknown landscape, we can determine the processes that created it and its development history. This was the case in the Pathfinder/Sojourner panoramas. [2]. DISCUSSION Planetary landscape evolution. We can draw a raw landscape develop- ment history by adding the different landscape building elements to each other. This has a strong connection with the planet's thermal evolution (age of the planet or the present surface materials) and with orbital parameters (distance from the central star, orbit excentricity etc). This way we can build a complex system in which we use differ- ent evolutional stages of lithologic, atmospheric, hydrologic and biogenic conditions which determine the given - Solar System or exoplanetary - landscape. Landscape elements. "Simple" landscapes can be found on asteroids: no linear horizon is present (not differentiated body, only impact structures), no atmosphere (therefore no atmospheric scattering - black sky as part of the landscape) and no

  16. Planetary Seismometers: An Overview

    Science.gov (United States)

    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.

  17. Super-long Anabiosis of Ancient Microorganisms in Ice and Terrestrial Models for Development of Methods to Search for Life on Mars, Europa and other Planetary Bodies

    Science.gov (United States)

    Abyzov, S. S.; Duxbury, N. S.; Bobin, N. E.; Fukuchi, M.; Hoover, R. B.; Kanda, H.; Mitskevich, I. N.; Mulyukin, A. L.; Naganuma, T.; Poglazova, M. N.; Ivanov, M. V.

    2007-01-01

    Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects.

  18. Constraints on the location of a putative distant massive body in the Solar System and on the External Field Effect of MOND from recent planetary data

    CERN Document Server

    Iorio, Lorenzo

    2011-01-01

    We analytically work out the long-term variations caused on the motion of a planet orbiting a star by a distant, pointlike massive object X (Planet X/Nemesis/Tyche). It turns out that, apart from the semimajor axis $a$, all the other Keplerian orbital elements of the perturbed planet experience long-term variations which are complicated functions of the orbital configurations of both the planet itself and of X. A numerical integration of the equations of motion of the perturbed planet yielding the temporal evolution of all its orbital elements successfully confirms our analytical results. We infer constraints on the minimum distance $d_{\\rm X}$ at which the putative body X can exist by comparing, first, our prediction of the long-term variation of the longitude of the perihelion $\\varpi$ to the latest empirical determinations of the corrections $\\Delta\\dot\\varpi$ to the standard Newtonian/Einsteinian secular precessions of several planets of the solar system recently obtained. Independent teams of astronomers...

  19. Lunar and Planetary Science XXXVI, Part 6

    Science.gov (United States)

    2005-01-01

    Contents include the following: A Model for Multiple Populations of Presolar Diamonds. Characterization of Martian North Polar Geologic Units Using Mars Odyssey THEMIS Data. Effect of Flow on the Internal Structure of the Martian North Polar Layered Deposits. Elemental Abundance Distributions in Basalt Clays and Meteorites: Is It a Biosignature? Early Results on the Saturn System from the Composite Infrared Spectrometer. NanoSIMS D/H Imaging of Isotopically Primitive Interplanetary Dust Particles. Presolar (Circumstellar and Interstellar) Phases in Renazzo: The Effects of Parent Body Processing. Catastrophic Disruption of Hydrated Targets: Implications for the Hydrated Asteroids and for the Production of Interplanetary Dust Particles. Chemical and Mineralogical Analyses of Particles from the Stratospheric Collections Coinciding with the 2002 Leonid Storm and the 2003 Comet Grigg-Skjellerup Trail Passage. An Analysis of the Solvus in the CaS-MnS System. ESA s SMART-1 Mission at the Moon: First Results, Status and Next Steps. Europa Analog Ice-splitting Measurements and Experiments with Ice-Hunveyor on the Frozen Balaton-Lake, Hungary. Chromium on Eros: Further Evidence of Ordinary Chondrite Composition. Dust Devil Tracks on Mars: Observation and Analysis from Orbit and the Surface. Spatial Variation of Methane and Other Trace Gases Detected on Mars: Interpretation with a General Circulation Model. Mars Water Ice and Carbon Dioxide Seasonal Polar Caps: GCM Modeling and Comparison with Mars Express Omega Observations. Component Separation of OMEGA Spectra with ICA. Clathrate Formation in the Near-Surface Environment of Titan. Space Weathering: A Proposed Laboratory Approach to Explaining the Sulfur Depletion on Eros. Sample Collection from Small Airless Bodies: Examination of Temperature Constraints for the TGIP. Sample Collector for the Hera Near-Earth Asteroid Sample Return Mission. A Rugged Miniature Mass-Spectrometer for Measuring Aqueous Geochemistry on Mars

  20. Planetary geosciences, 1988

    Science.gov (United States)

    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.

  1. Earth and planetary sciences

    International Nuclear Information System (INIS)

    The earth is a dynamic body. The major surface manifestation of this dynamism has been fragmentation of the earth's outer shell and subsequent relative movement of the pieces on a large scale. Evidence for continental movement came from studies of geomagnetism. As the sea floor spreads and new crust is formed, it is magnetized with the polarity of the field at the time of its formation. The plate tectonics model explains the history, nature, and topography of the oceanic crust. When a lithospheric plate surmounted by continental crust collides with an oceanic lithosphere, it is the denser oceanic lithosphere that is subducted. Hence the ancient oceans have vanished and the knowledge of ancient earth will require deciphering the complex continental geological record. Geochemical investigation shows that the source region of continental rocks is not simply the depleted mantle that is characteristic of the source region of basalts produced at the oceanic ridges. The driving force of plate tectonics is convection within the earth, but much remains to be learned about the convection and interior of the earth. A brief discussion of planetary exploration is given

  2. Planetary mass function and planetary systems

    OpenAIRE

    Dominik, M.

    2010-01-01

    With planets orbiting stars, a planetary mass function should not be seen as a low-mass extension of the stellar mass function, but a proper formalism needs to take care of the fact that the statistical properties of planet populations are linked to the properties of their respective host stars. This can be accounted for by describing planet populations by means of a differential planetary mass-radius-orbit function, which together with the fraction of stars with given properties that are orb...

  3. Planetary Atmospheric Electricity

    CERN Document Server

    Leblanc, F; Yair, Y; Harrison, R. G; Lebreton, J. P; Blanc, M

    2008-01-01

    This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to t...

  4. Next Generation Gamma/Neutron Detectors for Planetary Science. Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Gamma-ray and neutron spectroscopy are well established techniques for determining the chemical composition of planetary surfaces, and small cosmic bodies such as...

  5. Next Generation Gamma/Neutron Detectors for Planetary Science. Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Gamma ray and neutron spectroscopy are well established techniques for determining the chemical composition of planetary surfaces, and small cosmic bodies such as...

  6. Life on Earth and other planetary bodies

    CERN Document Server

    Hanslmeier, Arnold; Seckbach, Joseph

    2012-01-01

    This volume covers aspects of life on Earth with all its diversity and the possibilities of extraterrestrial life. It presents contributions by experts from 20 countries who discuss astrobiology emphasizing life "as we know it" to extraterrestrial places.

  7. The PSA: Planetary Science Archive

    Science.gov (United States)

    Barthelemy, M.; Martinez, S.; Heather, D.; Vazquez, J. L.; Arviset, C.; Osuna, P.; PSA development Team

    2012-04-01

    through to validation and ingestion of the products into the archive. All data in the PSA are compatible with the Planetary Data System (PDS) Standard of NASA, and the PSA staff work in close collaboration with the PDS staff. To ensure a common archiving approach for all of ESA's planetary missions as well as to provide a similar data quality and standard for end users, a tool has been developed supporting the instrument teams in syntactically validating their datasets before delivering to the PSA. This tool, and the overall archiving process is being streamlined in line with the re-development of the science ground segment for Rosetta. This will be very important for the efficient handling and release of data during Rosetta's encounter with the comet Churyamov-Gerasimenko. A PSA advisory body has been established in order to assess the continuing development of the PSA. The advisory panel aims to meet regularly, reviewing the progress on defined requirements and providing feedback on our activities. New areas of data exploitation include attempts to standardize the way in which planetary data sets are constructed internationally. This is driving towards 'interoperability' of the data systems maintained at all Agencies archiving planetary data, and it is hoped that in the long-run any data can be obtained from any of the co-operating archives using the same protocol. Representatives from most major archiving agencies are members of the International Planetary Data Alliance (IPDA), and regular meetings are now taking place as standards are discussed.

  8. Planetary mass function and planetary systems

    CERN Document Server

    Dominik, M

    2010-01-01

    With planets orbiting stars, a planetary mass function should not be seen as a low-mass extension of the stellar mass function, but a proper formalism needs to take care of the fact that the statistical properties of planet populations are linked to the properties of their respective host stars. This can be accounted for by describing planet populations by means of a differential planetary mass-radius-orbit function, which together with the fraction of stars with given properties that are orbited by planets and the stellar mass function allows to derive all statistics for any considered sample. These fundamental functions provide a framework for comparing statistics that result from different observing techniques and campaigns which all have their very specific selection procedures and detection efficiencies. Moreover, recent results both from gravitational microlensing campaigns and radial-velocity surveys of stars indicate that planets tend to cluster in systems rather than being the lonely child of their r...

  9. Liberating exomoons in white dwarf planetary systems

    CERN Document Server

    Payne, Matthew J; Holman, Matthew J; Gaensicke, Boris T

    2016-01-01

    Previous studies indicate that more than a quarter of all white dwarf (WD) atmospheres are polluted by remnant planetary material, with some WDs being observed to accrete the mass of Pluto in 10^6 years. The short sinking timescale for the pollutants indicate that the material must be frequently replenished. Moons may contribute decisively to this pollution process if they are liberated from their parent planets during the post-main-sequence evolution of the planetary systems. Here, we demonstrate that gravitational scattering events among planets in WD systems easily triggers moon ejection. Repeated close encounters within tenths of a planetary Hill radii are highly destructive to even the most massive, close-in moons. Consequently, scattering increases both the frequency of perturbing agents in WD systems, as well as the available mass of polluting material in those systems, thereby enhancing opportunities for collision and fragmentation and providing more dynamical pathways for smaller bodies to reach the ...

  10. The Planetary Project

    Science.gov (United States)

    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.

  11. Missions to Near-Earth Asteroids: Implications for Exploration, Science, Resource Utilization, and Planetary Defense

    Science.gov (United States)

    Abell, P. A.; Sanders, G. B.; Mazanek, D. D.; Barbee, B. W.; Mink, R. G.; Landis, R. R.; Adamo, D. R.; Johnson, L. N.; Yeomans, D. K.; Reeves, D. M.; Drake, B. G.; Friedensen, V. P.

    2012-12-01

    Considerations: These missions would be the first human expeditions to interplanetary bodies beyond the Earth-Moon system and would prove useful for testing technologies required for human missions to Mars, Phobos and Deimos, and other Solar System destinations. Current analyses of operational concepts suggest that stay times of 15 to 30 days may be possible at a NEA with total mission duration limits of 180 days or less. Hence, these missions would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while simultaneously conducting detailed investigations of these primitive objects with instruments and equipment that exceed the mass and power capabilities delivered by robotic spacecraft. All of these activities will be vital for refinement of resource characterization/identification and development of extraction/utilization technologies to be used on airless bodies under low- or micro-gravity conditions. In addition, gaining enhanced understanding of a NEA's geotechnical properties and its gross internal structure will assist the development of hazard mitigation techniques for planetary defense. Conclusions: The scientific, resource utilization, and hazard mitigation benefits, along with the programmatic and operational benefits of a human venture beyond the Earth-Moon system, make a piloted sample return mission to a NEA using NASA's proposed human exploration systems a compelling endeavor.

  12. Missions to Near-Earth Asteroids: Implications for Exploration, Science, Resource Utilization, and Planetary Defense

    Science.gov (United States)

    Abell, P. A.; Sanders, G. B.; Mazanek, D. D.; Barbee, B. W.; Mink, R. G.; Landis, R. R.; Adamo, D. R.; Johnson, L. N.; Yeomans, D. K.; Reeves, D. M.; Drake, B. G.; Friedensen, V. P.

    2012-01-01

    Considerations: These missions would be the first human expeditions to interplanetary bodies beyond the Earth-Moon system and would prove useful for testing technologies required for human missions to Mars, Phobos and Deimos, and other Solar System destinations. Current analyses of operational concepts suggest that stay times of 15 to 30 days may be possible at a NEA with total mission duration limits of 180 days or less. Hence, these missions would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while simultaneously conducting detailed investigations of these primitive objects with instruments and equipment that exceed the mass and power capabilities delivered by robotic spacecraft. All of these activities will be vital for refinement of resource characterization/identification and development of extraction/utilization technologies to be used on airless bodies under low- or micro-gravity conditions. In addition, gaining enhanced understanding of a NEA s geotechnical properties and its gross internal structure will assist the development of hazard mitigation techniques for planetary defense. Conclusions: The scientific, resource utilization, and hazard mitigation benefits, along with the programmatic and operational benefits of a human venture beyond the Earth-Moon system, make a piloted sample return mission to a NEA using NASA s proposed human exploration systems a compelling endeavor.

  13. Planetary mass function and planetary systems

    Science.gov (United States)

    Dominik, M.

    2011-02-01

    With planets orbiting stars, a planetary mass function should not be seen as a low-mass extension of the stellar mass function, but a proper formalism needs to take care of the fact that the statistical properties of planet populations are linked to the properties of their respective host stars. This can be accounted for by describing planet populations by means of a differential planetary mass-radius-orbit function, which together with the fraction of stars with given properties that are orbited by planets and the stellar mass function allows the derivation of all statistics for any considered sample. These fundamental functions provide a framework for comparing statistics that result from different observing techniques and campaigns which all have their very specific selection procedures and detection efficiencies. Moreover, recent results both from gravitational microlensing campaigns and radial-velocity surveys of stars indicate that planets tend to cluster in systems rather than being the lonely child of their respective parent star. While planetary multiplicity in an observed system becomes obvious with the detection of several planets, its quantitative assessment however comes with the challenge to exclude the presence of further planets. Current exoplanet samples begin to give us first hints at the population statistics, whereas pictures of planet parameter space in its full complexity call for samples that are 2-4 orders of magnitude larger. In order to derive meaningful statistics, however, planet detection campaigns need to be designed in such a way that well-defined fully deterministic target selection, monitoring and detection criteria are applied. The probabilistic nature of gravitational microlensing makes this technique an illustrative example of all the encountered challenges and uncertainties.

  14. Analytical Treatment of Planetary Resonances

    CERN Document Server

    Batygin, Konstantin

    2013-01-01

    An ever-growing observational aggregate of extrasolar planets has revealed that systems of planets that reside in or near mean-motion resonances are relatively common. While the origin of such systems is attributed to protoplanetary disk-driven migration, a qualitative description of the dynamical evolution of resonant planets remains largely elusive. Aided by the pioneering works of the last century, we formulate an approximate, integrable theory for first-order resonant motion. We utilize the developed theory to construct an intuitive, geometrical representation of resonances within the context of the unrestricted three-body problem. Moreover, we derive a simple analytical criterion for the appearance of secondary resonances between resonant and secular motion. Subsequently, we demonstrate the onset of rapid chaotic motion as a result of overlap among neighboring first-order mean-motion resonances, as well as the appearance of slow chaos as a result of secular modulation of the planetary orbits. Finally, we...

  15. Special Software for Planetary Image Processing and Research

    Science.gov (United States)

    Zubarev, A. E.; Nadezhdina, I. E.; Kozlova, N. A.; Brusnikin, E. S.; Karachevtseva, I. P.

    2016-06-01

    The special modules of photogrammetric processing of remote sensing data that provide the opportunity to effectively organize and optimize the planetary studies were developed. As basic application the commercial software package PHOTOMOD™ is used. Special modules were created to perform various types of data processing: calculation of preliminary navigation parameters, calculation of shape parameters of celestial body, global view image orthorectification, estimation of Sun illumination and Earth visibilities from planetary surface. For photogrammetric processing the different types of data have been used, including images of the Moon, Mars, Mercury, Phobos, Galilean satellites and Enceladus obtained by frame or push-broom cameras. We used modern planetary data and images that were taken over the years, shooting from orbit flight path with various illumination and resolution as well as obtained by planetary rovers from surface. Planetary data image processing is a complex task, and as usual it can take from few months to years. We present our efficient pipeline procedure that provides the possibilities to obtain different data products and supports a long way from planetary images to celestial body maps. The obtained data - new three-dimensional control point networks, elevation models, orthomosaics - provided accurate maps production: a new Phobos atlas (Karachevtseva et al., 2015) and various thematic maps that derived from studies of planetary surface (Karachevtseva et al., 2016a).

  16. Correlation tracking for a Planetary Pointing and Tracking System

    Science.gov (United States)

    Assefi, T.

    1978-01-01

    The Planetary Pointing and Tracking System (PPTS) is being developed to provide precision pointing for science platforms on future autonomous planetary spacecraft. The PPTS design approach using a CCD optical sensor for closed-loop control with respect to the target body, a gyro for inertial stabilization, and brushless dc torque motors for smooth and continuous platform articulation is essential for high resolution planetary imaging and automated science execution. An integral part of PPTS is the correlation tracker which has the potential to revolutionize autonomous guidance.

  17. Image Processing for Planetary Limb/Terminator Extraction

    Science.gov (United States)

    Udomkesmalee, S.; Zhu, D. Q.; Chu, C. -C.

    1995-01-01

    A novel image segmentation technique for extracting limb and terminator of planetary bodies is proposed. Conventional edge- based histogramming approaches are used to trace object boundaries. The limb and terminator bifurcation is achieved by locating the harmonized segment in the two equations representing the 2-D parameterized boundary curve. Real planetary images from Voyager 1 and 2 served as representative test cases to verify the proposed methodology.

  18. Planetary protection: lessons lemed

    Czech Academy of Sciences Publication Activity Database

    Perek, Luboš

    Houston : International Astronautical Federation, 2003, s. 462-465. [Colloquium on the Law of Outer Space /45./. Houston (US), 10.10.2002-19.10.2002] Institutional research plan: CEZ:AV0Z1003909 Keywords : planetary environment * voluntary regulation * space activities Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  19. Planetary protection: lessons learned

    Czech Academy of Sciences Publication Activity Database

    Perek, Luboš

    2004-01-01

    Roč. 34, č. 11 (2004), s. 2368-2370. ISSN 0273-1177 Institutional research plan: CEZ:AV0Z1003909 Keywords : planetary protection * space law * space debris Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.548, year: 2004

  20. The planetary scientist's companion

    CERN Document Server

    Lodders, Katharina

    1998-01-01

    A comprehensive and practical book of facts and data about the Sun, planets, asteroids, comets, meteorites, the Kuiper belt and Centaur objects in our solar system. Also covered are properties of nearby stars, the interstellar medium, and extra-solar planetary systems.

  1. Planetary Protection: Organisation, Requirements and Needs for Future Planetary Exploration Missions

    Science.gov (United States)

    Debus, A.

    2004-04-01

    According to the United Nations (UN) Space Treaties and in line with the COSPAR recommendations, the exploration of the Solar System needs to comply with planetary protection constraints in order to avoid the contamination of extraterrestrial bodies (particularly the biological contamination by terrestrial microorganisms), and to protect our Earth from an eventual contamination carried by return systems or return samples. Indirectly, it is also required to preserve the properties of extraterrestrial samples in order to conduct exobiological investigations with the maximum degree of confidence. These constraints impose unusual tasks based principally on sterilisation, sterile and ultraclean integration, microbiological and cleanliness control, the use of high reliability systems in order to avoid crashs, and to implement them during each concerned project development and operation. In the frame of future planetary missions, taking into past experience, the main needs can now been defined in order to conduct European missions in compliance with planetary protection regulations.

  2. Simulation of Planetary Formation using Python

    Science.gov (United States)

    Bufkin, James; Bixler, David

    2015-03-01

    A program to simulate planetary formation was developed in the Python programming language. The program consists of randomly placed and massed bodies surrounding a central massive object in order to approximate a protoplanetary disk. The orbits of these bodies are time-stepped, with accelerations, velocities and new positions calculated in each step. Bodies are allowed to merge if their disks intersect. Numerous parameters (orbital distance, masses, number of particles, etc.) were varied in order to optimize the program. The program uses an iterative difference equation approach to solve the equations of motion using a kinematic model. Conservation of energy and angular momentum are not specifically forced, but conservation of momentum is forced during the merging of bodies. The initial program was created in Visual Python (VPython) but the current intention is to allow for higher particle count and faster processing by utilizing PyOpenCl and PyOpenGl. Current results and progress will be reported.

  3. Forming different planetary systems

    Institute of Scientific and Technical Information of China (English)

    Ji-Lin Zhou; Ji-Wei Xie; Hui-Gen Liu; Hui Zhang; Yi-Sui Sun

    2012-01-01

    With the increasing number of detected exoplanet samples,the statistical properties of planetary systems have become much clearer.In this review,we summarize the major statistical results that have been revealed mainly by radial velocity and transiting observations,and try to interpret them within the scope of the classical core-accretion scenario of planet formation,especially in the formation of different orbital architectures for planetary systems around main sequence stars.Based on the different possible formation routes for different planet systems,we tentatively classify them into three major catalogs:hot Jupiter systems,standard systems and distant giant planet systems.The standard systems can be further categorized into three sub-types under different circumstances:solar-like systems,hot Super-Earth systems,and subgiant planet systems.We also review the theory of planet detection and formation in binary systems as well as planets in star clusters.

  4. The Role of Planetary Data System Archive Standards in International Planetary Data Archives

    Science.gov (United States)

    Guinness, Edward; Slavney, Susan; Beebe, Reta; Crichton, Daniel

    A major objective of NASA's Planetary Data System (PDS) is to efficiently archive and make accessible digital data produced by NASA's planetary missions, research programs, and data analysis programs. The PDS is comprised of a federation of groups known as nodes, with each node focused on archiving and managing planetary data from a given science discipline. PDS nodes include Atmospheres, Geosciences, Small Bodies (asteroids, comets, and dust), Rings, Planetary Plasma Interactions, and Imaging. There are also support nodes for engineering, radio science, and ancillary data, such as geometry information. The PDS archives include space-borne, ground-based, and laboratory experiment data from several decades of NASA exploration of comets, asteroids, moons, and planets. PDS archives are peer-reviewed, welldocumented, and accessible online via web sites, catalogs, and other user-interfaces that provide search and retrieval capabilities. Current holdings within the PDS online repositories total approximately 50 TB of data. Over the next few years, the PDS is planning for a rapid expansion in the volume of data being delivered to its archives. The archive standards developed by the PDS are crucial elements for producing planetary data archives that are consistent across missions and planetary science disciplines and that yield archives that are useable by the planetary research community. These standards encompass the full range of archiving needs. They include standards for the format of data products and the metadata needed to detail how observations were made. They also specify how data products and ancillary information such as documentation, calibration, and geometric information are packaged into data sets. The PDS standards are documented in its Planetary Science Data Dictionary and in its Standards Reference Document and Archive Preparation Guide. The PDS standards are being used to design and implement data archives for current and future NASA planetary missions

  5. Europa Planetary Protection for Juno Jupiter Orbiter

    Science.gov (United States)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2010-01-01

    NASA's Juno mission launched in 2011 and will explore the Jupiter system starting in 2016. Juno's suite of instruments is designed to investigate the atmosphere, gravitational fields, magnetic fields, and auroral regions. Its low perijove polar orbit will allow it to explore portions of the Jovian environment never before visited. While the Juno mission is not orbiting or flying close to Europa or the other Galilean satellites, planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design.The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  6. Europa planetary protection for Juno Jupiter Orbiter

    Science.gov (United States)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2013-08-01

    NASA's Juno mission launched in 2011 and will explore Jupiter and its near environment starting in 2016. Planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design. In particular Juno's polar orbit, which enables scientific investigations of parts of Jupiter's environment never before visited, also greatly assist avoiding close flybys of Europa and the other Galilean satellites. The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  7. Estimating Tides from a Planetary Flyby Mission

    Science.gov (United States)

    Mazarico, Erwan; Genova, Antonio; Smith, David; Zuber, Maria; Sun, Xiaoli

    2014-05-01

    Previous and current laser altimeter instruments (e.g. MOLA, NLR, LOLA, MLA) acquired measurements in orbit to provide global topography and study the surface and sub-surface properties of planetary bodies. We show that altimetric data from multiple flybys can make significant contributions to the geophysical understanding of the target body. In particular, the detection of the body tide (e.g. surface deformation due to the tides raised by the Sun or the parent body) and the estimation of its amplitude can yield critical information about the interior structure. We conduct a full simulation of a planetary flyby mission around Europa. We use the GEODYN II program developed and maintained at NASA GSFC to process altimetric and radiometric tracking data created using truth models. The data are processed in short two-day segments (arcs) centered on each closest approach. The initial trajectory is integrated using a priori (truth) models of the planetary ephemeris, the gravity field, the tidal Love numbers k2 and h2 (which describe the amplitudes of the time-variable tidal potential and the time-variable radial deformation respectively). The gravity field is constructed using a Kaula-like power law and scaling considerations from other planetary bodies. The global-scale static topography is also chosen to follow a power law, and higher-resolution local maps consistent with recent stereo-topography work are used to assess the expected variations along altimetric profiles. We assume realistic spacecraft orientation to drive a spacecraft macro-model and model the solar radiation pressure acceleration. Radiometric tracking data are generated from the truth trajectory accounting for geometry (occultations by Europa or Jupiter or the Sun), DSN visibility and scheduling (8h per day) and measurement noise (Ka-band quality, plasma noise). Doppler data have a 10-second integration step while Range data occur every 5 minutes. The altimetric data are generated using realistic

  8. Planetary polarization nephelometer

    Science.gov (United States)

    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

  9. Highly miniaturized laser ablation time-of-flight mass spectrometer for a planetary rover

    International Nuclear Information System (INIS)

    We report the development and testing of a highly miniaturized mass spectrometer and ion source intended to be deployed on an airless planetary surface to measure the elemental and isotopic composition of solids, e.g., rocks and soils. Our design concentrates at this stage on the proposed BepiColombo mission to the planet Mercury. The mass analyzer is a novel combination of an electrostatic analyzer and a reflectron time-of-flight design. The ion source utilizes a laser induced plasma, which is directly coupled into the mass analyzer. Laser ablation gives high spatial resolution and avoids the need for sample preparation. Our prototype instrument has a demonstrated mass resolution m/Δm full width at half maximum in excess of 180 and a predicted dynamic range of better than five orders of magnitude. We estimate that a flight instrument would have a mass of 280 g (including laser and all electronics), a volume of 84 cm3, and could operate on 3 W power

  10. Planetary Science with Balloon-Borne Telescopes

    Science.gov (United States)

    Kremic, Tibor; Cheng, Andy; Hibbitts, Karl; Young, Eliot

    2015-01-01

    The National Aeronautics and Space Administration (NASA) and the planetary science community have recently been exploring the potential contributions of stratospheric balloons to the planetary science field. A study that was recently concluded explored the roughly 200 or so science questions raised in the Planetary Decadal Survey report and found that about 45 of those questions are suited to stratospheric balloon based observations. In September of 2014, a stratospheric balloon mission called BOPPS (which stands for Balloon Observation Platform for Planetary Science) was flown out of Fort Sumner, New Mexico. The mission had two main objectives, first, to observe a number of planetary targets including one or more Oort cloud comets and second, to demonstrate the applicability and performance of the platform, instruments, and subsystems for making scientific measurements in support planetary science objectives. BOPPS carried two science instruments, BIRC and UVVis. BIRC is a cryogenic infrared multispectral imager which can image in the.6-5 m range using an HgCdTe detector. Narrow band filters were used to allow detection of water and CO2 emission features of the observed targets. The UVVis is an imager with the science range of 300 to 600 nm. A main feature of the UVVis instrument is the incorporation of a guide camera and a Fine Steering Mirror (FSM) system to reduce image jitter to less than 100 milliarcseconds. The BIRC instrument was used to image targets including Oort cloud comets Siding Spring and Jacques, and the dwarf planet 1 Ceres. BOPPS achieved the first ever earth based CO2 observation of a comet and the first images of water and CO2 of an Oort cloud comet (Jacques). It also made the first ever measurement of 1Ceres at 2.73 m to refine the shape of the infrared water absorption feature on that body. The UVVis instrument, mounted on its own optics bench, demonstrated the capability for image correction both from atmospheric disturbances as well as some

  11. Online Planetary Science Courses at Athabasca University

    Science.gov (United States)

    Connors, M. G.; Bredeson, C.; Munyikwa, K.

    2014-12-01

    Athabasca University offers distance education courses in science, at freshman and higher levels. It has a number of geology courses, and recently opened a planetary science course as the first upper division astronomy course after many years of offering freshman astronomy. Astronomy 310, Planetary Science, focuses on the physics of the Solar System and allows the study of planetary astronomy in a deeper way than what is offered in a freshman course. With a mathematically based approach, it looks at the planets and smaller bodies such as meteoroids, asteroids and comets found in our own solar neighbourhood. It provides an understanding of the basic physics and equations needed for studies of planetary science and looks at the formation of the principal bodies in the Solar System. It investigates the interiors of planets and planetary surface phenomena such as cratering, volcanism and tectonics, and examines the atmospheres of planets, including how they originated and whether planets can keep an atmosphere. As a new course, it has grown rapidly.Geology 415, Earth's Origin and Early Evolution, explores the evidence for the various processes, events, and materials involved in the formation and evolution of Earth. The course provides an overview of objects in the Solar System, including the Sun, the planets, asteroids, comets, and meteoroids. Earth's place in the Solar System is examined and physical laws that govern the motion of objects in the universe are looked at. Various geochemical tools and techniques used by geologists to reveal and interpret the evidence for the formation and evolution of bodies in the Solar System as well as the age of Earth are also explored. After looking at lines of evidence used to reconstruct the evolution of the Solar System, processes involved in the formation of planets and stars are examined. The course concludes with a look at the origin and nature of Earth's internal structure. GEOL415 is a senior undergraduate course and enrols

  12. Lightning detection in planetary atmospheres

    CERN Document Server

    Aplin, Karen L

    2016-01-01

    Lightning in planetary atmospheres is now a well-established concept. Here we discuss the available detection techniques for, and observations of, planetary lightning by spacecraft, planetary landers and, increasingly, sophisticated terrestrial radio telescopes. Future space missions carrying lightning-related instrumentation are also summarised, specifically the European ExoMars mission and Japanese Akatsuki mission to Venus, which could both yield lightning observations in 2016.

  13. A High Speed, Radiation Hard X-Ray Imaging Spectroscometer for Planetary Investigations

    Science.gov (United States)

    Kraft, R. P.; Kenter, A. T.; Murray, S. S.; Martindale, A.; Pearson, J.; Gladstone, R.; Branduardi-Raymont, G.; Elsner, R.; Kimura, T.; Ezoe, Y.; Grant, C.; Roediger, E.; Howell, R.; Elvis, M.; Smith, R.; Campbell, B.; Morgenthaler, J.; Kravens, T.; Steffl, A. J.; Hong, J.

    2014-01-01

    X-ray observations provide a unique window into fundamental processes in planetary physics, and one that is complementary to observations obtained at other wavelengths. We propose to develop an X-ray imaging spectrometer (0.1-10 keV band) that, on orbital planetary missions, would measure the elemental composition, density, and temperature of the hot plasma in gas giant magnetospheres, the interaction of the Solar wind with the upper atmospheres of terrestrial planets, and map the elemental composition of the surfaces of the Galilean moons and rocky or icy airless systems on spatial scales as small as a few meters. The X-ray emission from gas giants, terrestrial planets and moons with atmospheres, displays diverse characteristics that depend on the Solar wind's interaction with their upper atmospheres and/or magnetospheres. Our imaging spectrometer, as part of a dedicated mission to a gas giant, will be a paradigm changing technology. On a mission to the Jovian system, our baseline instrument would map the elemental composition of the rocky and icy surfaces of the Galilean moons via particle-induced X-ray fluorescence. This instrument would also measure the temperature, density and elemental abundance of the thermal plasma in the magnetosphere and in the Io plasma torus (IPT), explore the interaction of the Solar wind with the magnetosphere, and characterize the spectrum, flux, and temporal variability of X-ray emission from the polar auroras. We will constrain both the mode of energy transport and the effective transport coefficients in the IPT and throughout the Jovian magnetosphere by comparing temporal and spatial variations of the X-ray emitting plasma with those seen from the cooler but energetically dominant 5 eV plasma.

  14. Stratospheric Balloons for Planetary Science and the Balloon Observation Platform for Planetary Science (BOPPS) Mission Summary

    Science.gov (United States)

    Kremic, Tibor; Cheng, Andrew F.; Hibbitts, Karl; Young, Eliot F.; Ansari, Rafat R.; Dolloff, Matthew D.; Landis, Rob R.

    2015-01-01

    NASA and the planetary science community have been exploring the potential contributions approximately 200 questions raised in the Decadal Survey have identified about 45 topics that are potentially suitable for addressing by stratospheric balloon platforms. A stratospheric balloon mission was flown in the fall of 2014 called BOPPS, Balloon Observation Platform for Planetary Science. This mission observed a number of planetary targets including two Oort cloud comets. The optical system and instrumentation payload was able to provide unique measurements of the intended targets and increase our understanding of these primitive bodies and their implications for us here on Earth. This paper will discuss the mission, instrumentation and initial results and how these may contribute to the broader planetary science objectives of NASA and the scientific community. This paper will also identify how the instrument platform on BOPPS may be able to contribute to future balloon-based science. Finally the paper will address potential future enhancements and the expected science impacts should those enhancements be implemented.

  15. Sonar equations for planetary exploration.

    Science.gov (United States)

    Ainslie, Michael A; Leighton, Timothy G

    2016-08-01

    The set of formulations commonly known as "the sonar equations" have for many decades been used to quantify the performance of sonar systems in terms of their ability to detect and localize objects submerged in seawater. The efficacy of the sonar equations, with individual terms evaluated in decibels, is well established in Earth's oceans. The sonar equations have been used in the past for missions to other planets and moons in the solar system, for which they are shown to be less suitable. While it would be preferable to undertake high-fidelity acoustical calculations to support planning, execution, and interpretation of acoustic data from planetary probes, to avoid possible errors for planned missions to such extraterrestrial bodies in future, doing so requires awareness of the pitfalls pointed out in this paper. There is a need to reexamine the assumptions, practices, and calibrations that work well for Earth to ensure that the sonar equations can be accurately applied in combination with the decibel to extraterrestrial scenarios. Examples are given for icy oceans such as exist on Europa and Ganymede, Titan's hydrocarbon lakes, and for the gaseous atmospheres of (for example) Jupiter and Venus. PMID:27586766

  16. The final fate of planetary systems

    Science.gov (United States)

    Gaensicke, Boris

    2015-12-01

    The discovery of the first extra-solar planet around a main-sequence star in 1995 has changed the way we think about the Universe: our solar system is not unique. Twenty years later, we know that planetary systems are ubiquitous, orbit stars spanning a wide range in mass, and form in an astonishing variety of architectures. Yet, one fascinating aspect of planetary systems has received relatively little attention so far: their ultimate fate.Most planet hosts will eventually evolve into white dwarfs, Earth-sized stellar embers, and the outer parts of their planetary systems (in the solar system, Mars and beyond) can survive largely intact for billions of years. While scattered and tidally disrupted planetesimals are directly detected at a small number of white dwarfs in the form infrared excess, the most powerful probe for detecting evolved planetary systems is metal pollution of the otherwise pristine H/He atmospheres.I will present the results of a multi-cycle HST survey that has obtained COS observations of 136 white dwarfs. These ultraviolet spectra are exquisitely sensitive to the presence of metals contaminating the white atmosphere. Our sophisticated model atmosphere analysis demonstrates that at least 27% of all targets are currently accreting planetary debris, and an additional 29% have very likely done so in the past. These numbers suggest that planet formation around A-stars (the dominant progenitors of today's white dwarf population) is similarly efficient as around FGK stars.In addition to post-main sequence planetary system demographics, spectroscopy of the debris-polluted white dwarf atmospheres provides a direct window into the bulk composition of exo-planetesimals, analogous to the way we use of meteorites to determine solar-system abundances. Our ultraviolet spectroscopy is particularly sensitive to the detection of Si, a dominant rock-forming species, and we identify up to ten additional volatile and refractory elements in the most strongly

  17. Theoretical models of planetary system formation

    International Nuclear Information System (INIS)

    Full text: Planet formation models have been developed during the last years in order to try to reproduce and predict observations of the solar system and extra solar planets. Using a modular planetary system formation model combining an extended core-accretion model including migration, disc evolution and gap formation with an N-Body part for the dynamical interactions we perform population synthesis calculations in order to investigate the effect of the formation of more than one planet in the same protoplanetary disc. We show the modifications of masses and semi-major axis through competition and gravitational interactions varying the number of forming planets. (author)

  18. NASA's Planetary Science Missions and Participations

    Science.gov (United States)

    Green, James

    2016-04-01

    another instrument. This was a tremendously successful activity leading to another similar call for instrument proposals for the Europa mission that is currently under definition by NASA. Europa mission instruments will be used to conduct high priority scientific investigations addressing the science goals for the moon's exploration outlined in the National Resource Council's Planetary Decadal Survey, Vision and Voyages (2011). The selection of these instruments will be announced in the late spring or early summer. International partnerships are an excellent, proven way of amplifying the scope and sharing the science results of a mission otherwise implemented by an individual space agency. The exploration of the Solar System is uniquely poised to bring planetary scientists, worldwide, together under the common theme of understanding the origin, evolution, and bodies of our solar neighborhood. In the past decade we have witnessed great examples of international partnerships that made various missions the success they are known for today. As Director of Planetary Science at NASA I will continue to seek cooperation with our strong international partners in support of planetary missions.

  19. Evidence for Surface Volatiles on the Moon and Mercury: A Planetary Comparison

    Science.gov (United States)

    Siegler, M. A.; Miller, E.; Lucey, P. G.; Hayne, P. O.; Neumann, G. A.; Paige, D. A.; Greenhagen, B. T.

    2016-05-01

    We evaluate evidence from UV and near infrared reflectance data for surface volatiles on the Moon and Mercury. Comparison of these planetary bodies leads to new understanding (and questions) regarding water in the inner solar system.

  20. Planetary Doppler Imaging

    Science.gov (United States)

    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

  1. Interdisciplinary Research Produces Results in the Understanding of Planetary Dunes

    Science.gov (United States)

    Titus, Timothy N.; Hayward, Rosalyn Kay; Bourke, Mary C.

    2010-08-01

    Second International Planetary Dunes Workshop: Planetary Analogs—Integrating Models, Remote Sensing, and Field Data; Alamosa, Colorado, 18-21 May 2010; Dunes and other eolian bed forms are prominent on several planetary bodies in our solar system. Despite 4 decades of study, many questions remain regarding the composition, age, and origins of these features, as well as the climatic conditions under which they formed. Recently acquired data from orbiters and rovers, together with terrestrial analogs and numerical models, are providing new insights into Martian sand dunes, as well as eolian bed forms on other terrestrial planetary bodies (e.g., Titan). As a means of bringing together terrestrial and planetary researchers from diverse backgrounds with the goal of fostering collaborative interdisciplinary research, the U.S. Geological Survey (USGS), the Carl Sagan Center for the Study of Life in the Universe, the Desert Research Institute, and the U.S. National Park Service held a workshop in Colorado. The small group setting facilitated intensive discussion of problems and issues associated with eolian processes on Earth, Mars, and Titan.

  2. Planetary internal structures

    CERN Document Server

    Baraffe, I; Fortney, J; Sotin, C

    2014-01-01

    This chapter reviews the most recent advancements on the topic of terrestrial and giant planet interiors, including Solar System and extrasolar objects. Starting from an observed mass-radius diagram for known planets in the Universe, we will discuss the various types of planets appearing in this diagram and describe internal structures for each type. The review will summarize the status of theoretical and experimental works performed in the field of equation of states (EOS) for materials relevant to planetary interiors and will address the main theoretical and experimental uncertainties and challenges. It will discuss the impact of new EOS on interior structures and bulk composition determination. We will discuss important dynamical processes which strongly impact the interior and evolutionary properties of planets (e.g plate tectonics, semiconvection) and describe non standard models recently suggested for our giant planets. We will address the case of short-period, strongly irradiated exoplanets and critica...

  3. Photochemistry in planetary atmospheres

    Science.gov (United States)

    Levine, J. S.; Graedel, T. E.

    1981-01-01

    Widely varying paths of evolutionary history, atmospheric processes, solar fluxes, and temperatures have produced vastly different planetary atmospheres. The similarities and differences between the earth atmosphere and those of the terrestrial planets (Venus and Mars) and of the Jovian planets are discussed in detail; consideration is also given to the photochemistry of Saturn, Uranus, Pluto, Neptune, Titan, and Triton. Changes in the earth's ancient atmosphere are described, and problems of interest in the earth's present troposphere are discussed, including the down wind effect, plume interactions, aerosol nucleation and growth, acid rain, and the fate of terpenes. Temperature fluctuations in the four principal layers of the earth's atmosphere, predicted decreases in the ozone concentration as a function of time, and spectra of particles in the earth's upper atmosphere are also presented. Finally, the vertical structure of the Venus cloud system and the thermal structure of the Jovian planets are shown graphically.

  4. HUBBLE'S PLANETARY NEBULA GALLERY

    Science.gov (United States)

    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

  5. Planetary protection for humans in space: Mars and the Moon

    Science.gov (United States)

    Conley, Catharine A.; Rummel, John D.

    When searching for life beyond Earth, the unique capabilities provided by human astronauts will only be advantageous if the biological contamination associated with human presence is monitored and minimized. Controlling biological contamination during planetary exploration is termed 'planetary protection,' and will be a critical element in the human exploration of other solar system bodies. To ensure the safety and health of the astronauts and the Earth, while preserving science value, planetary protection considerations must be incorporated from the earliest stages of mission planning and development. Issues of concern to planetary protection involve both 'forward contamination,' which is the contamination of other solar system bodies by Earth microbes and organic materials, and 'backward contamination,' which is the contamination of Earth systems by potential alien life. Forward contamination concerns include contamination that might invalidate current or future scientific exploration of a particular solar system body, and that may disrupt the planetary environment or a potential endogenous (alien) ecosystem. Backward contamination concerns include both immediate and long-term effects on the health of the astronaut explorers from possible biologically active materials encountered during exploration, as well as the possible contamination of the Earth. A number of national and international workshops held over the last seven years have generated a consensus regarding planetary protection policies and requirements for human missions to Mars, and a 2007 workshop held by NASA has considered the issues and benefits to planetary protection that might be offered by a return to the Moon. Conclusions from these workshops recognize that some degree of forward contamination associated with human astronaut explorers is inevitable. Nonetheless, the principles and policies of planetary protection, developed by COSPAR in conformance with the 1967 Outer Space Treaty, can and

  6. Termination of planetary accretion due to gap formation

    CERN Document Server

    Rafikov, R R

    2001-01-01

    The process of gap formation by a growing planetary embryo embedded in a planetesimal disk is considered. It is shown that there exists a single parameter characterizing this process, which represents the competition between the gravitational influence of the embryo and planetesimal-planetesimal scattering. For realistic assumptions about the properties of the planetesimal disk and the planetary embryo, a gap is opened long before the embryo can accrete all the bodies within its region of influence. The implication of this result is that the embryo stops growing and, thus, large bodies formed during the coagulation stage should be less massive than is usually assumed. For conditions expected at 1 AU in the solar protoplanetary disk, gap formation is expected to occur around bodies of mass < 10^24 g. The effect of protoplanetary radial migration is also discussed.

  7. Planetary Vital Signs

    Science.gov (United States)

    Kennel, Charles; Briggs, Stephen; Victor, David

    2016-07-01

    The climate is beginning to behave in unusual ways. The global temperature reached unprecedented highs in 2015 and 2016, which led climatologists to predict an enormous El Nino that would cure California's record drought. It did not happen the way they expected. That tells us just how unreliable temperature has become as an indicator of important aspects of climate change. The world needs to go beyond global temperature to a set of planetary vital signs. Politicians should not over focus policy on one indicator. They need to look at the balance of evidence. A coalition of scientists and policy makers should start to develop vital signs at once, since they should be ready at the entry into force of the Paris Agreement in 2020. But vital signs are only the beginning. The world needs to learn how to use the vast knowledge we will be acquiring about climate change and its impacts. Is it not time to use all the tools at hand- observations from space and ground networks; demographic, economic and societal measures; big data statistical techniques; and numerical models-to inform politicians, managers, and the public of the evolving risks of climate change at global, regional, and local scales? Should we not think in advance of an always-on social and information network that provides decision-ready knowledge to those who hold the responsibility to act, wherever they are, at times of their choosing?

  8. The fragility of planetary systems

    OpenAIRE

    Zwart, Simon Portegies; Jilkova, Lucie

    2015-01-01

    We specify the range to which perturbations penetrate a planetesimal system. Such perturbations can originate from massive planets or from encounters with other stars. The latter can have an origin in the star cluster in which the planetary system was born, or from random encounters once the planetary system has escaped its parental cluster. The probability of a random encounter, either in a star cluster or in the Galactic field depends on the local stellar density, the velocity dispersion an...

  9. Electromagnetic signals from planetary collisions

    OpenAIRE

    Zhang, Bing; Sigurdsson, Steinn

    2003-01-01

    Planet-planet collisions are expected during the early stages of the formation of extra-solar planets, and are also possible in mature planetary systems through secular planet-planet perturbations. We investigate the electromagnetic signals accompanied with these planetary collisions and their event rate, and explore the possibility of directly detecting such events. A typical Earth-Jupiter collision would give rise to a prompt EUV-soft-X-ray flash lasting for hours and a bright IR afterglow ...

  10. Planetary GIS and EuroPlanet-RI H2020

    Science.gov (United States)

    Rossi, A. P.; Cecconi, B.; Manaud, N.; Erard, S.; Marmo, C.

    2015-10-01

    Geographic Information System (GIS) practice and applications within Planetary Science became in the last decade a major component for studying solid surfaces of Solar System bodies [e.g. 1,2,3]: from earlier mainly Mars-focused efforts limited to few datasets, the availability of high-quality spatial data grew enormously and its accessibility is also enhanced by the use of OGC web standards. Higher-level, calibrated georeferenced datasets are the prime target for geologic and related thematic mapping [e.g. 4], although the communities potentially benefiting from a GIS-based approach are beyond and they include most closely Atmospheric science, as well as Magnetospheric and Plasma Physics, to quote only few. In the upcoming EuroPlanet-RI H2020 project Planetary GIS efforts are embedded within the VESPA activity [5] and they allow for a tight integration of OGC and VO-based tools and interfaces [6]. Nowadays GIS-based analyses are used for carrying out research tasks and systematic mapping on planetary bodies, but also for a wide range of analyses related [e.g. 7] to landing site selection, ranging from scientific merit to safety [e.g.8] Community building is a key part of VESPA [5], but also independently followed by other actors like ESA PSA [9]. Recently a workshop on Planetary GIS in broad sense and with particular reference to ESA data archives has been organized [10]. Such workshop has been strongly supported by ESA and the broad planetary community, both directly and through its official channel for Planetary Science archive science access and exploitation-related needs, the PSA User Group [11]. Its outcomes, also in terms of use case development, might be instrumental to VESPA GIS/VO future activities

  11. Fluorine-Rich Planetary Environments as Possible Habitats for Life

    Directory of Open Access Journals (Sweden)

    Nediljko Budisa

    2014-08-01

    Full Text Available In polar aprotic organic solvents, fluorine might be an element of choice for life that uses selected fluorinated building blocks as monomers of choice for self-assembling of its catalytic polymers. Organofluorine compounds are extremely rare in the chemistry of life as we know it. Biomolecules, when fluorinated such as peptides or proteins, exhibit a “fluorous effect”, i.e., they are fluorophilic (neither hydrophilic nor lipophilic. Such polymers, capable of creating self-sorting assemblies, resist denaturation by organic solvents by exclusion of fluorocarbon side chains from the organic phase. Fluorous cores consist of a compact interior, which is shielded from the surrounding solvent. Thus, we can anticipate that fluorine-containing “teflon”-like or “non-sticking” building blocks might be monomers of choice for the synthesis of organized polymeric structures in fluorine-rich planetary environments. Although no fluorine-rich planetary environment is known, theoretical considerations might help us to define chemistries that might support life in such environments. For example, one scenario is that all molecular oxygen may be used up by oxidation reactions on a planetary surface and fluorine gas could be released from F-rich magma later in the history of a planetary body to result in a fluorine-rich planetary environment.

  12. Fluorine-rich planetary environments as possible habitats for life.

    Science.gov (United States)

    Budisa, Nediljko; Kubyshkin, Vladimir; Schulze-Makuch, Dirk

    2014-01-01

    In polar aprotic organic solvents, fluorine might be an element of choice for life that uses selected fluorinated building blocks as monomers of choice for self-assembling of its catalytic polymers. Organofluorine compounds are extremely rare in the chemistry of life as we know it. Biomolecules, when fluorinated such as peptides or proteins, exhibit a "fluorous effect", i.e., they are fluorophilic (neither hydrophilic nor lipophilic). Such polymers, capable of creating self-sorting assemblies, resist denaturation by organic solvents by exclusion of fluorocarbon side chains from the organic phase. Fluorous cores consist of a compact interior, which is shielded from the surrounding solvent. Thus, we can anticipate that fluorine-containing "teflon"-like or "non-sticking" building blocks might be monomers of choice for the synthesis of organized polymeric structures in fluorine-rich planetary environments. Although no fluorine-rich planetary environment is known, theoretical considerations might help us to define chemistries that might support life in such environments. For example, one scenario is that all molecular oxygen may be used up by oxidation reactions on a planetary surface and fluorine gas could be released from F-rich magma later in the history of a planetary body to result in a fluorine-rich planetary environment. PMID:25370378

  13. Extrasolar Planetary Systems

    Science.gov (United States)

    Ksanfomaliti, L. V.

    2000-11-01

    The discovery of planetary systems around alien stars is an outstanding achievement of recent years. The idea that the Solar System may be representative of planetary systems in the Galaxy in general develops upon the knowledge, current until the last decade of the 20th century, that it is the only object of its kind. Studies of the known planets gave rise to a certain stereotype in theoretical research. Therefore, the discovery of exoplanets, which are so different from objects of the Solar System, alters our basic notions concerning the physics and very criteria of normal planets. A substantial factor in the history of the Solar System was the formation of Jupiter. Two waves of meteorite bombardment played an important role in that history. Ultimately there arose a stable low-entropy state of the Solar System, in which Jupiter and the other giants in stable orbits protect the inner planets from impacts by dangerous celestial objects, reducing this danger by many orders of magnitude. There are even variants of the anthropic principle maintaining that life on Earth owes its genesis and development to Jupiter. Some 20 companions more or less similar to Jupiter in mass and a few ``infrared dwarfs,'' have been found among the 500 solar-type stars belonging to the main sequence. Approximately half of the exoplanets discovered are of the ``hot-Jupiter'' type. These are giants, sometimes of a mass several times that of Jupiter, in very low orbits and with periods of 3-14 days. All of their parent stars are enriched with heavy elements, [Fe/H] = 0.1-0.2. This may indicate that the process of exoplanet formation depends on the chemical composition of the protoplanetary disk. The very existence of exoplanets of the hot-Jupiter type considered in the context of new theoretical work comes up against the problem of the formation of Jupiter in its real orbit. All the exoplanets in orbits with a semimajor axis of more than 0.15-0.20 astronomical units (AU) have orbital

  14. Planetary Geophysics and Tectonics

    Science.gov (United States)

    Zuber, Maria

    2005-01-01

    The broad objective of this work is to improve understanding of the internal structures and thermal and stress histories of the solid planets by combining results from analytical and computational modeling, and geophysical data analysis of gravity, topography and tectonic surface structures. During the past year we performed two quite independent studies in the attempt to explain the Mariner 10 magnetic observations of Mercury. In the first we revisited the possibility of crustal remanence by studying the conditions under which one could break symmetry inherent in Runcorn's model of a uniformly magnetized shell to produce a remanent signal with a dipolar form. In the second we applied a thin shell dynamo model to evaluate the range of intensity/structure for which such a planetary configuration can produce a dipole field consistent with Mariner 10 results. In the next full proposal cycle we will: (1) develop numerical and analytical and models of thin shell dynamos to address the possible nature of Mercury s present-day magnetic field and the demise of Mars magnetic field; (2) study the effect of degree-1 mantle convection on a core dynamo as relevant to the early magnetic field of Mars; (3) develop models of how the deep mantles of terrestrial planets are perturbed by large impacts and address the consequences for mantle evolution; (4) study the structure, compensation, state of stress, and viscous relaxation of lunar basins, and address implications for the Moon s state of stress and thermal history by modeling and gravity/topography analysis; and (5) use a three-dimensional viscous relaxation model for a planet with generalized vertical viscosity distribution to study the degree-two components of the Moon's topography and gravity fields to constrain the primordial stress state and spatial heterogeneity of the crust and mantle.

  15. Solar system astrophysics planetary atmospheres and the outer solar system

    CERN Document Server

    Milone, Eugene F

    2014-01-01

    The second edition of Solar System Astrophysics: Planetary Atmospheres and the Outer Solar System provides a timely update of our knowledge of planetary atmospheres and the bodies of the outer solar system and their analogs in other planetary systems. This volume begins with an expanded treatment of the physics, chemistry, and meteorology of the atmospheres of the Earth, Venus, and Mars, moving on to their magnetospheres and then to a full discussion of the gas and ice giants and their properties. From here, attention switches to the small bodies of the solar system, beginning with the natural satellites. Then comets, meteors, meteorites, and asteroids are discussed in order, and the volume concludes with the origin and evolution of our solar system. Finally, a fully revised section on extrasolar planetary systems puts the development of our system in a wider and increasingly well understood galactic context. All of the material is presented within a framework of historical importance. This book and its sist...

  16. Planetary Science Research Discoveries (PSRD): Effective Education and Outreach Website at http://www.soest.hawaii.edu/PSRdiscoveries

    Science.gov (United States)

    Taylor, G. J.; Martel, L. M. V.

    2000-01-01

    Planetary Science Research Discoveries (PSRD) website reports the latest research about planets, meteorites, and other solar system bodies being made by NASA-sponsored scientists. In-depth articles explain research results and give insights to contemporary questions in planetary science.

  17. Planetary cubesats - mission architectures

    Science.gov (United States)

    Bousquet, Pierre W.; Ulamec, Stephan; Jaumann, Ralf; Vane, Gregg; Baker, John; Clark, Pamela; Komarek, Tomas; Lebreton, Jean-Pierre; Yano, Hajime

    2016-07-01

    Miniaturisation of technologies over the last decade has made cubesats a valid solution for deep space missions. For example, a spectacular set 13 cubesats will be delivered in 2018 to a high lunar orbit within the frame of SLS' first flight, referred to as Exploration Mission-1 (EM-1). Each of them will perform autonomously valuable scientific or technological investigations. Other situations are encountered, such as the auxiliary landers / rovers and autonomous camera that will be carried in 2018 to asteroid 1993 JU3 by JAXA's Hayabusas 2 probe, and will provide complementary scientific return to their mothership. In this case, cubesats depend on a larger spacecraft for deployment and other resources, such as telecommunication relay or propulsion. For both situations, we will describe in this paper how cubesats can be used as remote observatories (such as NEO detection missions), as technology demonstrators, and how they can perform or contribute to all steps in the Deep Space exploration sequence: Measurements during Deep Space cruise, Body Fly-bies, Body Orbiters, Atmospheric probes (Jupiter probe, Venus atmospheric probes, ..), Static Landers, Mobile landers (such as balloons, wheeled rovers, small body rovers, drones, penetrators, floating devices, …), Sample Return. We will elaborate on mission architectures for the most promising concepts where cubesat size devices offer an advantage in terms of affordability, feasibility, and increase of scientific return.

  18. Planetary Image Geometry Library

    Science.gov (United States)

    Deen, Robert C.; Pariser, Oleg

    2010-01-01

    The Planetary Image Geometry (PIG) library is a multi-mission library used for projecting images (EDRs, or Experiment Data Records) and managing their geometry for in-situ missions. A collection of models describes cameras and their articulation, allowing application programs such as mosaickers, terrain generators, and pointing correction tools to be written in a multi-mission manner, without any knowledge of parameters specific to the supported missions. Camera model objects allow transformation of image coordinates to and from view vectors in XYZ space. Pointing models, specific to each mission, describe how to orient the camera models based on telemetry or other information. Surface models describe the surface in general terms. Coordinate system objects manage the various coordinate systems involved in most missions. File objects manage access to metadata (labels, including telemetry information) in the input EDRs and RDRs (Reduced Data Records). Label models manage metadata information in output files. Site objects keep track of different locations where the spacecraft might be at a given time. Radiometry models allow correction of radiometry for an image. Mission objects contain basic mission parameters. Pointing adjustment ("nav") files allow pointing to be corrected. The object-oriented structure (C++) makes it easy to subclass just the pieces of the library that are truly mission-specific. Typically, this involves just the pointing model and coordinate systems, and parts of the file model. Once the library was developed (initially for Mars Polar Lander, MPL), adding new missions ranged from two days to a few months, resulting in significant cost savings as compared to rewriting all the application programs for each mission. Currently supported missions include Mars Pathfinder (MPF), MPL, Mars Exploration Rover (MER), Phoenix, and Mars Science Lab (MSL). Applications based on this library create the majority of operational image RDRs for those missions. A

  19. The study about planetary gearbox virtual prototyping with nonlinear gear contact characteristics

    International Nuclear Information System (INIS)

    The virtual prototypes of gear transmission system built in most multi-body dynamic software have difficulties in describing the gear mesh characteristics. The gear mesh contact is modelled as rigid contact and this is not accurate for the gear mesh contact, which is elastic or flexible. The gear contact formula used in the multi-body dynamic software does not reveal the gear contact nonlinear stiffness characteristic. The model built with gear meshing contact is difficult to solve because of its time-consuming algorithm. In the paper a new method is put forward to build the virtual prototype of planetary gearbox system according to the nonlinear mesh stiffness and mesh phase obtained through FEM models. This new FEM method of gear mesh stiffness calculation is much more accurate than the common formulas. The gear mesh nonlinear stiffness of sun gear- pinion and pinion-ring gear of all the planetary gear sets in gearbox are obtained through MATALB code, which is used to read and plot the analyzing result data. The gear mesh phase differences between different pinions with suns or rings of different planetary gear set can be also obtained. With all these data modelled in simulink (or other software) and integrated with the multi-body dynamic planetary gearbox model and the gear meshing contact problem in multi-body gear models is solved easily and accurately. The interfaces for gear mesh stiffness and mesh phases are designed for multi-body dynamic model and simulink. The nonlinear planetary gear set prototyping models are integrated to become the whole planetary gear box model and the whole vehicle system model built in multi-body dynamic software can be integrated to simulate different duty conditions. At last high speed input is put into the nonlinear planetary transmission model and the different duty cases are simulated. The dynamic characteristics of different parts are obtained. The dynamic characteristic comparison between nonlinear and linear models is made

  20. Robotic vehicles for planetary exploration

    Science.gov (United States)

    Wilcox, Brian; Matthies, Larry; Gennery, Donald; Cooper, Brian; Nguyen, Tam; Litwin, Todd; Mishkin, Andrew; Stone, Henry

    A program to develop planetary rover technology is underway at the Jet Propulsion Laboratory (JPL) under sponsorship of the National Aeronautics and Space Administration. Developmental systems with the necessary sensing, computing, power, and mobility resources to demonstrate realistic forms of control for various missions have been developed, and initial testing has been completed. These testbed systems and the associated navigation techniques used are described. Particular emphasis is placed on three technologies: Computer-Aided Remote Driving (CARD), Semiautonomous Navigation (SAN), and behavior control. It is concluded that, through the development and evaluation of such technologies, research at JPL has expanded the set of viable planetary rover mission possibilities beyond the limits of remotely teleoperated systems such as Lunakhod. These are potentially applicable to exploration of all the solid planetary surfaces in the solar system, including Mars, Venus, and the moons of the gas giant planets.

  1. Planetary systems in star clusters

    CERN Document Server

    Kouwenhoven, M B N; Cai, Maxwell Xu; Spurzem, Rainer

    2016-01-01

    Thousands of confirmed and candidate exoplanets have been identified in recent years. Consequently, theoretical research on the formation and dynamical evolution of planetary systems has seen a boost, and the processes of planet-planet scattering, secular evolution, and interaction between planets and gas/debris disks have been well-studied. Almost all of this work has focused on the formation and evolution of isolated planetary systems, and neglect the effect of external influences, such as the gravitational interaction with neighbouring stars. Most stars, however, form in clustered environments that either quickly disperse, or evolve into open clusters. Under these conditions, young planetary systems experience frequent close encounters with other stars, at least during the first 1-10 Myr, which affects planets orbiting at any period range, as well as their debris structures.

  2. Robotic vehicles for planetary exploration

    Science.gov (United States)

    Wilcox, Brian; Matthies, Larry; Gennery, Donald; Cooper, Brian; Nguyen, Tam; Litwin, Todd; Mishkin, Andrew; Stone, Henry

    1992-01-01

    A program to develop planetary rover technology is underway at the Jet Propulsion Laboratory (JPL) under sponsorship of the National Aeronautics and Space Administration. Developmental systems with the necessary sensing, computing, power, and mobility resources to demonstrate realistic forms of control for various missions have been developed, and initial testing has been completed. These testbed systems and the associated navigation techniques used are described. Particular emphasis is placed on three technologies: Computer-Aided Remote Driving (CARD), Semiautonomous Navigation (SAN), and behavior control. It is concluded that, through the development and evaluation of such technologies, research at JPL has expanded the set of viable planetary rover mission possibilities beyond the limits of remotely teleoperated systems such as Lunakhod. These are potentially applicable to exploration of all the solid planetary surfaces in the solar system, including Mars, Venus, and the moons of the gas giant planets.

  3. Variational Principle for Planetary Interiors

    CERN Document Server

    Zeng, Li

    2016-01-01

    In the past few years, the number of confirmed planets has grown above 2000. It is clear that they represent a diversity of structures not seen in our own solar system. In addition to very detailed interior modeling, it is valuable to have a simple analytical framework for describing planetary structures. Variational principle is a fundamental principle in physics, entailing that a physical system follows the trajectory which minimizes its action. It is alternative to the differential equation formulation of a physical system. Applying this principle to planetary interior can beautifully summarize the set of differential equations into one, which provides us some insight into the problem. From it, a universal mass-radius relation, an estimate of error propagation from equation of state to mass-radius relation, and a form of virial theorem applicable to planetary interiors are derived.

  4. Astrophysical Conditions for Planetary Habitability

    CERN Document Server

    Guedel, M; Erkaev, N; Kasting, J; Khodachenko, M; Lammer, H; Pilat-Lohinger, E; Rauer, H; Ribas, I; Wood, B E

    2014-01-01

    With the discovery of hundreds of exoplanets and a potentially huge number of Earth-like planets waiting to be discovered, the conditions for their habitability have become a focal point in exoplanetary research. The classical picture of habitable zones primarily relies on the stellar flux allowing liquid water to exist on the surface of an Earth-like planet with a suitable atmosphere. However, numerous further stellar and planetary properties constrain habitability. Apart from "geophysical" processes depending on the internal structure and composition of a planet, a complex array of astrophysical factors additionally determine habitability. Among these, variable stellar UV, EUV, and X-ray radiation, stellar and interplanetary magnetic fields, ionized winds, and energetic particles control the constitution of upper planetary atmospheres and their physical and chemical evolution. Short- and long-term stellar variability necessitates full time-dependent studies to understand planetary habitability at any point ...

  5. Atomic hydrogen in planetary nebulae

    International Nuclear Information System (INIS)

    The authors searched for neutral atomic hydrogen associated with 22 planetary nebulae and three evolved stars in the 21 cm line at the Arecibo Observatory. Objects whose radial velocities permitted discrimination from Galactic H I were chosen for observation. Hydrogen was detected in absorption from IC 4997. From the measurements new low limits are derived to the mass of atomic hydrogen associated with the undetected nebulae. Radio continuum observations were also made of several of the nebulae at 12.6 cm. The authors reexamine previous measurements of H I in planetary nebulae, and present the data on a consistent footing. The question of planetary nebula distances is considered at length. Finally, implications of the H I measurements for nebular evolution are discussed and it is suggested that atomic hydrogen seen in absorption was expelled from the progenitor star during the final 1000 yr prior to the onset of ionization. 68 references

  6. Do tidal or swing waves roughen planetary surfaces?

    Science.gov (United States)

    Kochemasov, Gennady G.

    2010-05-01

    Surfaces of the terrestrial planets and their moons are far from being smooth. They are warped by several wavelengths and show a remarkable regularity: their roughness increases with the solar distance. Thus, if for Mercury the surface relief range does not exceed several km, for Mars it is already about 30 km. Earth's range is 20 km, Venus' one 14 km. Recently it was shown that this row of ranges reflects ratios of the tectonic granules radii of terrestrial planets [1, 2]. These radii related to unity of reduced planetary globes (in a geometrical model all planets are represented by even circles [2]) are as follows: Mercury πR/16, Venus πR/6, Earth πR/4, Mars πR/2. It means that in the great planetary circles (equators) there are 32, 12, 8, and 4 tectonic granules (now they all are mapped by remote methods) and their numbers are inversely proportional to the orbital frequencies of the planets: higher frequency - smaller granule, and, vice versa, lower frequency - larger granule. In this planetary law is a firm confirmation of the main conceptual point of the wave planetology: "Orbits make structures" [3]. But how this happens? A basic reason lies in the keplerian elliptical orbits implying periodical changes of planetary bodies accelerations. Periodical slowing down and speeding up produce inertia-gravity waves warping any celestial body. In rotating bodies this wave warping is divided in four directions: two orthogonal and two diagonal. An interference of these directions produces tectonic blocks of three kinds: uplifting, subsiding, and neutral. Sizes and amplitudes of the blocks (granules) depend on the warping wavelengths and increase with the solar distance. Thus, a relief-forming potential and the actual relief range observed on the planets increase in this direction [1, 2, 4]. But the tidal forces diminish in this direction. That is why they cannot be a reason for the relief-forming potential. Having in mind a swinging action of planetary orbits on

  7. IDIS: Progresses towards a Virtual Observatory in Planetary Science

    Science.gov (United States)

    Le Sidaner, P.; Andre, N.; Berthier, J.; Bourrel, N.; Cecconi, B.; Despan, D.; Erard, S.; Gangloff, M.; Henry, F.; Jacquey, C.; Leyrat, C.; Sarkissian, A.; Saunier, M.

    2012-09-01

    The Integrated and Distributed Information Service (IDIS) is as a network activity inside the Europlanet-RI FP7 program. Based on a network of thematic nodes, IDIS aims at building the basis of a Planetary Science. The large range of scientific fields (Solar system bodies interiors and surfaces, atmospheres, plasmas, small bodies and dust, dynamics and extraterrestrial matter) requires to create a very open data model to define data contents, structure and context, but also protocols to access the relevant data. Moreover this action is embedded in the context of VO normalization where many tasks have already been completed. IDIS needs interoperability and interactions with other projects, in particular with SPASE, International Virtual Observatory Alliance, International Planetary Data Alliance, Virtual Atomic and Molecular Data Centre, and HELIO. Most of these programs are presented in this meeting. We will present the status of the different elements composing the IDIS VO infrastructure.

  8. From Planetary Mapping to Map Production: Planetary Cartography as integral discipline in Planetary Sciences

    Science.gov (United States)

    Nass, Andrea; van Gasselt, Stephan; Hargitai, Hendrik; Hare, Trent; Manaud, Nicolas; Karachevtseva, Irina; Kersten, Elke; Roatsch, Thomas; Wählisch, Marita; Kereszturi, Akos

    2016-04-01

    Cartography is one of the most important communication channels between users of spatial information and laymen as well as the open public alike. This applies to all known real-world objects located either here on Earth or on any other object in our Solar System. In planetary sciences, however, the main use of cartography resides in a concept called planetary mapping with all its various attached meanings: it can be (1) systematic spacecraft observation from orbit, i.e. the retrieval of physical information, (2) the interpretation of discrete planetary surface units and their abstraction, or it can be (3) planetary cartography sensu strictu, i.e., the technical and artistic creation of map products. As the concept of planetary mapping covers a wide range of different information and knowledge levels, aims associated with the concept of mapping consequently range from a technical and engineering focus to a scientific distillation process. Among others, scientific centers focusing on planetary cartography are the United State Geological Survey (USGS, Flagstaff), the Moscow State University of Geodesy and Cartography (MIIGAiK, Moscow), Eötvös Loránd University (ELTE, Hungary), and the German Aerospace Center (DLR, Berlin). The International Astronomical Union (IAU), the Commission Planetary Cartography within International Cartographic Association (ICA), the Open Geospatial Consortium (OGC), the WG IV/8 Planetary Mapping and Spatial Databases within International Society for Photogrammetry and Remote Sensing (ISPRS) and a range of other institutions contribute on definition frameworks in planetary cartography. Classical cartography is nowadays often (mis-)understood as a tool mainly rather than a scientific discipline and an art of communication. Consequently, concepts of information systems, mapping tools and cartographic frameworks are used interchangeably, and cartographic workflows and visualization of spatial information in thematic maps have often been

  9. Interplanetary Laser Ranging. Analysis for Implementation in Planetary Science Missions

    Science.gov (United States)

    Dirkx, Dominic

    2015-10-01

    Measurements of the motion of natural (and artificial) bodies in the solar system provide key input on their interior structre and properties. Currently, the most accurate measurements of solar system dynamics are performed using radiometric tracking systems on planetary missions, providing range measurement with an accuracy in the order of 1 m. Laser ranging to Earth-orbiting satellites equipped with laser retroreflectors provides range data with (sub-)cm accuracy. Extending this technology to planetary missions, however, requires the use of an active space segment equipped with a laser detector and transmitter (for a two-way system). The feasibility of such measurements have been demonstrated at planetary distances, and used operationally (with a one-way system) for the Lunar Reconaissance Orbiter (LRO) mission. The topic of this dissertation is the analysis of the application of interplanetary laser ranging (ILR) to improve the science return from next-generation space missions, with a focus on planetary science objectives. We have simulated laser ranging data for a variety of mission and system architectures, analyzing the influence of both model and measurement uncertainties. Our simulations show that the single-shot measurement precision is relatively inconsequential compared to the systematic range errors, providing a strong rationale for the consistent use of single-photon signal-intensity operation. We find that great advances in planetary geodesy (tidal, rotational characteristics, etc.) could be achieved by ILR. However, the laser data should be accompanied by commensurate improvements in other measurements and data analysis models to maximize the system's science return. The science return from laser ranging data will be especially strong for planetary landers, with a radio system remaining the preferred choice for many orbiter missions. Furthermore, we conclude that the science case for a one-way laser ranging is relatively weak compared to next

  10. Get Involved in Planetary Discoveries through New Worlds, New Discoveries

    Science.gov (United States)

    Shupla, Christine; Shipp, S. S.; Halligan, E.; Dalton, H.; Boonstra, D.; Buxner, S.; SMD Planetary Forum, NASA

    2013-01-01

    "New Worlds, New Discoveries" is a synthesis of NASA’s 50-year exploration history which provides an integrated picture of our new understanding of our solar system. As NASA spacecraft head to and arrive at key locations in our solar system, "New Worlds, New Discoveries" provides an integrated picture of our new understanding of the solar system to educators and the general public! The site combines the amazing discoveries of past NASA planetary missions with the most recent findings of ongoing missions, and connects them to the related planetary science topics. "New Worlds, New Discoveries," which includes the "Year of the Solar System" and the ongoing celebration of the "50 Years of Exploration," includes 20 topics that share thematic solar system educational resources and activities, tied to the national science standards. This online site and ongoing event offers numerous opportunities for the science community - including researchers and education and public outreach professionals - to raise awareness, build excitement, and make connections with educators, students, and the public about planetary science. Visitors to the site will find valuable hands-on science activities, resources and educational materials, as well as the latest news, to engage audiences in planetary science topics and their related mission discoveries. The topics are tied to the big questions of planetary science: how did the Sun’s family of planets and bodies originate and how have they evolved? How did life begin and evolve on Earth, and has it evolved elsewhere in our solar system? Scientists and educators are encouraged to get involved either directly or by sharing "New Worlds, New Discoveries" and its resources with educators, by conducting presentations and events, sharing their resources and events to add to the site, and adding their own public events to the site’s event calendar! Visit to find quality resources and ideas. Connect with educators, students and the public to

  11. Planetary evolution and habitability

    Science.gov (United States)

    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

  12. Searching for stable orbits in the HD 10180 planetary system

    Directory of Open Access Journals (Sweden)

    Laskar J.

    2011-02-01

    Full Text Available A planetary system with at least seven planets has been found around the star HD 10180. However, the traditional Keplerian and n-body fits to the data provide an orbital solution that becomes unstable very quickly, which may quest the reliability of the observations. Here we show that stable orbital configurations can be obtained if general relativity and long-term dissipation raised by tides on the innermost planet are taken into account.

  13. Spice Tools Supporting Planetary Remote Sensing

    Science.gov (United States)

    Acton, C.; Bachman, N.; Semenov, B.; Wright, E.

    2016-06-01

    NASA's "SPICE"* ancillary information system has gradually become the de facto international standard for providing scientists the fundamental observation geometry needed to perform photogrammetry, map making and other kinds of planetary science data analysis. SPICE provides position and orientation ephemerides of both the robotic spacecraft and the target body; target body size and shape data; instrument mounting alignment and field-of-view geometry; reference frame specifications; and underlying time system conversions. SPICE comprises not only data, but also a large suite of software, known as the SPICE Toolkit, used to access those data and subsequently compute derived quantities-items such as instrument viewing latitude/longitude, lighting angles, altitude, etc. In existence since the days of the Magellan mission to Venus, the SPICE system has continuously grown to better meet the needs of scientists and engineers. For example, originally the SPICE Toolkit was offered only in Fortran 77, but is now available in C, IDL, MATLAB, and Java Native Interface. SPICE calculations were originally available only using APIs (subroutines), but can now be executed using a client-server interface to a geometry engine. Originally SPICE "products" were only available in numeric form, but now SPICE data visualization is also available. The SPICE components are free of cost, license and export restrictions. Substantial tutorials and programming lessons help new users learn to employ SPICE calculations in their own programs. The SPICE system is implemented and maintained by the Navigation and Ancillary Information Facility (NAIF)-a component of NASA's Planetary Data System (PDS). * Spacecraft, Planet, Instrument, Camera-matrix, Events

  14. Online Planetary Science Courses at Athabasca University

    Science.gov (United States)

    Connors, Martin; Munyikwa, Ken; Bredeson, Christy

    2016-01-01

    Athabasca University offers distance education courses in science, at freshman and higher levels. It has a number of geology and astronomy courses, and recently opened a planetary science course as the first upper division astronomy course after many years of offering freshman astronomy. Astronomy 310, Planetary Science, focuses on process in the Solar System on bodies other than Earth. This process-oriented course uses W. F. Hartmann's "Moons and Planets" as its textbook. It primarily approaches the subject from an astronomy and physics perspective. Geology 415, Earth's Origin and Early Evolution, is based on the same textbook, but explores the evidence for the various processes, events, and materials involved in the formation and evolution of Earth. The course provides an overview of objects in the Solar System, including the Sun, the planets, asteroids, comets, and meteoroids. Earth's place in the solar system is examined and physical laws that govern the motion of objects in the universe are looked at. Various geochemical tools and techniques used by geologists to reveal and interpret the evidence for the formation and evolution of bodies in the solar system as well as the age of earth are also explored. After looking at lines of evidence used to reconstruct the evolution of the solar system, processes involved in the formation of planets and stars are examined. The course concludes with a look at the origin and nature of Earth's internal structure. GEOL415 is a senior undergraduate course and enrols about 15-30 students annually. The courses are delivered online via Moodle and student evaluation is conducted through assignments and invigilated examinations.

  15. Scattering Properties of Candidate Planetary Regolith Materials

    Science.gov (United States)

    Nelson, R. M.; Smythe, W. D.; Hapke, B. W.; Hale, A. S.; Piatek, J. A.

    2001-01-01

    The laboratory investigation of the scattering properties of candidate planetary regolith materials is an important technique for understanding the physical properties of a planetary regolith. Additional information is contained in the original extended abstract.

  16. Turning Planetary Theory Upside Down

    Science.gov (United States)

    2010-04-01

    Didier Queloz of Geneva Observatory. Two of the newly discovered retrograde planets have already been found to have more distant, massive companions that could potentially be the cause of the upset. These new results will trigger an intensive search for additional bodies in other planetary systems. This research was presented at the Royal Astronomical Society National Astronomy Meeting (NAM2010) that is taking place this week in Glasgow, Scotland. Nine publications submitted to international journals will be released on this occasion, four of them using data from ESO facilities. On the same occasion, the WASP consortium was awarded the 2010 Royal Astronomical Society Group Achievement Award. Notes [1] The current count of known exoplanets is 454. [2] The nine newly found exoplanets were discovered by the Wide Angle Search for Planets (WASP). WASP comprises two robotic observatories, each consisting of eight wide-angle cameras that simultaneously monitor the sky continuously for planetary transit events. A transit occurs when a planet passes in front of its parent star, temporarily blocking some of the light from it. The eight wide-angle cameras allow millions of stars to be monitored simultaneously to detect these rare transit events. The WASP cameras are operated by a consortium including Queen's University Belfast, the Universities of Keele, Leicester and St Andrews, the Open University, the Isaac Newton Group on La Palma and the Instituto Astrofisica Canarias. [3] To confirm the discovery and characterise a new transiting planet, it is necessary to do radial velocity follow-up to detect the wobble of the host star around its common centre of mass with the planet. This is done with a worldwide network of telescopes equipped with sensitive spectrometers. In the northern hemisphere, the Nordic Optical Telescope in the Canary Islands and the SOPHIE instrument on the 1.93-metre telescope at Haute-Provence in France lead the search. In the south, the HARPS exoplanet hunter

  17. Small Spacecraft for Planetary Science

    Science.gov (United States)

    Baker, John; Castillo-Rogez, Julie; Bousquet, Pierre-W.; Vane, Gregg; Komarek, Tomas; Klesh, Andrew

    2016-07-01

    As planetary science continues to explore new and remote regions of the Solar system with comprehensive and more sophisticated payloads, small spacecraft offer the possibility for focused and more affordable science investigations. These small spacecraft or micro spacecraft (electronics, advanced manufacturing for lightweight structures, and innovative propulsion are making it possible to fly much more capable micro spacecraft for planetary exploration. While micro spacecraft, such as CubeSats, offer significant cost reductions with added capability from advancing technologies, the technical challenges for deep space missions are very different than for missions conducted in low Earth orbit. Micro spacecraft must be able to sustain a broad range of planetary environments (i.e., radiations, temperatures, limited power generation) and offer long-range telecommunication performance on a par with science needs. Other capabilities needed for planetary missions, such as fine attitude control and determination, capable computer and data handling, and navigation are being met by technologies currently under development to be flown on CubeSats within the next five years. This paper will discuss how micro spacecraft offer an attractive alternative to accomplish specific science and technology goals and what relevant technologies are needed for these these types of spacecraft. Acknowledgements: Part of this work is being carried out at the Jet Propulsion Laboratory, California Institute of Technology under contract to NASA. Government sponsorship acknowledged.

  18. Small Spacecraft for Planetary Science

    Science.gov (United States)

    Baker, John; Castillo-Rogez, Julie; Bousquet, Pierre-W.; Vane, Gregg; Komarek, Tomas; Klesh, Andrew

    2016-07-01

    As planetary science continues to explore new and remote regions of the Solar system with comprehensive and more sophisticated payloads, small spacecraft offer the possibility for focused and more affordable science investigations. These small spacecraft or micro spacecraft (science-grade sensors and electronics, advanced manufacturing for lightweight structures, and innovative propulsion are making it possible to fly much more capable micro spacecraft for planetary exploration. While micro spacecraft, such as CubeSats, offer significant cost reductions with added capability from advancing technologies, the technical challenges for deep space missions are very different than for missions conducted in low Earth orbit. Micro spacecraft must be able to sustain a broad range of planetary environments (i.e., radiations, temperatures, limited power generation) and offer long-range telecommunication performance on a par with science needs. Other capabilities needed for planetary missions, such as fine attitude control and determination, capable computer and data handling, and navigation are being met by technologies currently under development to be flown on CubeSats within the next five years. This paper will discuss how micro spacecraft offer an attractive alternative to accomplish specific science and technology goals and what relevant technologies are needed for these these types of spacecraft. Acknowledgements: Part of this work is being carried out at the Jet Propulsion Laboratory, California Institute of Technology under contract to NASA. Government sponsorship acknowledged.

  19. Diagnostics of planetary nebulae plasma

    International Nuclear Information System (INIS)

    Starting with the pioneering Ambartsumian's papers, the problems of diagnostics of low density plasma of planetary nebulae are reviewed. We discuss both the early papers of Ambartsumian and the papers developing the methods of plasma diagnostics based on Ambartsumian's ideas. The diagnostics methods for both homogeneous and inhomogeneous nebular plasma are described

  20. SPICE Supports Planetary Science Observation Geometry

    Science.gov (United States)

    Hall Acton, Charles; Bachman, Nathaniel J.; Semenov, Boris V.; Wright, Edward D.

    2015-11-01

    "SPICE" is an information system, comprising both data and software, providing scientists with the observation geometry needed to plan observations from instruments aboard robotic spacecraft, and to subsequently help in analyzing the data returned from those observations. The SPICE system has been used on the majority of worldwide planetary exploration missions since the time of NASA's Galileo mission to Jupiter. Along with its "free" price tag, portability and the absence of licensing and export restrictions, its stable, enduring qualities help make it a popular choice. But stability does not imply rigidity-improvements and new capabilities are regularly added. This poster highlights recent additions that could be of interest to planetary scientists.Geometry Finder allows one to find all the times or time intervals when a particular geometric condition exists (e.g. occultation) or when a particular geometric parameter is within a given range or has reached a maximum or minimum.Digital Shape Kernel (DSK) provides means to compute observation geometry using accurately modeled target bodies: a tessellated plate model for irregular bodies and a digital elevation model for large, regular bodies.WebGeocalc (WGC) provides a graphical user interface (GUI) to a SPICE "geometry engine" installed at a mission operations facility, such as the one operated by NAIF. A WGC user need have only a computer with a web browser to access this geometry engine. Using traditional GUI widgets-drop-down menus, check boxes, radio buttons and fill-in boxes-the user inputs the data to be used, the kind of calculation wanted, and the details of that calculation. The WGC server makes the specified calculations and returns results to the user's browser.Cosmographia is a mission visualization program. This tool provides 3D visualization of solar system (target) bodies, spacecraft trajectory and orientation, instrument field-of-view "cones" and footprints, and more.The research described in this

  1. Report on the 2015 COSPAR Panel on Planetary Protection Colloquium

    Science.gov (United States)

    Hipkin, Victoria; Kminek, Gerhard

    2016-07-01

    In consultation with the COSPAR Scientific Commissions B (Space Studies of the Earth-Moon System, Planets, and Small Bodies of the Solar System) and F (Life Sciences as Related to Space), the COSPAR Panel on Planetary Protection organised a colloquium at the International Space Science Institute (ISSI) in Bern, Switzerland, in September 2015, to cover two pertinent topics: * Icy moon sample return planetary protection requirements * Mars Special Regions planetary protection requirements These two topics were addressed in two separate sessions. Participation from European, North American and Japanese scientists reflected broad expertise from the respective COSPAR Commissions, recent NASA MEPAG Science Analysis Group and National Academies of Sciences, Engineering, and Medicine/European Science Foundation Mars Special Regions Review Committee. The recommendations described in this report are based on discussions that took place during the course of the colloquium and reflect a consensus of the colloquium participants that participated in the two separate sessions. These recommendations are brought to the 2016 COSPAR Scientific Assembly for further input and discussion as part of the recognised process for updating COSPAR Planetary Protection Policy.

  2. Planetary Interiors and Geodesy

    Science.gov (United States)

    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.

  3. Exploring the planetary boundary for chemical pollution.

    Science.gov (United States)

    Diamond, Miriam L; de Wit, Cynthia A; Molander, Sverker; Scheringer, Martin; Backhaus, Thomas; Lohmann, Rainer; Arvidsson, Rickard; Bergman, Åke; Hauschild, Michael; Holoubek, Ivan; Persson, Linn; Suzuki, Noriyuki; Vighi, Marco; Zetzsch, Cornelius

    2015-05-01

    Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if "unacceptable global change" is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social

  4. Solar Variability and Planetary Climates

    CERN Document Server

    Calisesi, Y; Gray, L; Langen, J; Lockwood, M

    2007-01-01

    Variations in solar activity, as revealed by variations in the number of sunspots, have been observed since ancient times. To what extent changes in the solar output may affect planetary climates, though, remains today more than ever a subject of controversy. In 2000, the SSSI volume on Solar Variability and Climate reviewed the to-date understanding of the physics of solar variability and of the associated climate response. The present volume on Solar Variability and Planetary Climates provides an overview of recent advances in this field, with particular focus at the Earth's middle and lower atmosphere. The book structure mirrors that of the ISSI workshop held in Bern in June 2005, the collection of invited workshop contributions and of complementary introductory papers synthesizing the current understanding in key research areas such as middle atmospheric processes, stratosphere-troposphere dynamical coupling, tropospheric aerosols chemistry, solar storm influences, solar variability physics, and terrestri...

  5. Teaching, Learning, and Planetary Exploration

    Science.gov (United States)

    Brown, Robert A.

    2002-01-01

    This is the final report of a program that examined the fundamentals of education associated with space activities, promoted educational policy development in appropriate forums, and developed pathfinder products and services to demonstrate the utility of advanced communication technologies for space-based education. Our focus was on space astrophysics and planetary exploration, with a special emphasis on the themes of the Origins Program, with which the Principal Investigator (PI) had been involved from the outset. Teaching, Learning, and Planetary Exploration was also the core funding of the Space Telescope Science Institute's (ST ScI) Special Studies Office (SSO), and as such had provided basic support for such important NASA studies as the fix for Hubble Space Telescope (HST) spherical aberration, scientific conception of the HST Advanced Camera, specification of the Next-Generation Space Telescope (NGST), and the strategic plan for the second decade of the HST science program.

  6. Planetary engulfment as a trigger for white dwarf pollution

    CERN Document Server

    Petrovich, Cristobal

    2016-01-01

    The presence of a planetary system can shield a planetesimal disk from the secular gravitational perturbations due to distant outer massive objects (planets or stellar companions). As the host star evolves off the main sequence to become a white dwarf, these planets can be engulfed, triggering secular instabilities and leading to the tidal disruptions of small rocky bodies. These disrupted bodies can feed the white dwarfs with rocky material and possibly explain the high-metallicity material in their atmospheres. We illustrate how this mechanism can operate when the gravitational perturbations are due to the Kozai-Lidov mechanism from a stellar binary companion. We show that this mechanism can explain the observed levels of accretion if: (1) the planetary engulfment happens fast compared to the secular timescale, which is generally the case for wide binaries ($>100$ AU) and planetary engulfment during the Asymptotic Giant Branch; (2) the planetesimal disk has a total mass of $\\sim10^{-4}-10^{-2}M_\\oplus$. We ...

  7. Free vibration of planetary gearing

    Czech Academy of Sciences Publication Activity Database

    Půst, Ladislav; Pešek, Luděk; Radolfová, Alena

    Praha : Ústav termomechaniky AV ČR, v. v. i., 2015 - (Zolotarev, I.; Pešek, L.), s. 45-54 ISBN 978-80-87012-57-4. [DYMAMESI 2015. Praha (CZ), 24.11.2015] R&D Projects: GA TA ČR TA04011656 Institutional support: RVO:61388998 Keywords : four-planetary gear ing * free vibrations * input and output devices * torsion model Subject RIV: BI - Acoustics

  8. Dynamical evolution of planetary systems

    OpenAIRE

    Morbidelli, Alessandro

    2011-01-01

    to be published in "Planets, Stars and Stellar Systems", P. Kalas and L. French (eds.) The apparent regularity of the motion of the giant planets of our solar system suggested for decades that said planets formed onto orbits similar to the current ones and that nothing dramatic ever happened during their lifetime. The discovery of extra-solar planets showed astonishingly that the orbital structure of our planetary system is not typical. Many giant extra-solar planets have orbits with semi ...

  9. Northeast Regional Planetary Data Center

    Science.gov (United States)

    Schultz, Peter H.; Saunders, Stephen (Technical Monitor)

    2005-01-01

    In 1980, the Northeast Planetary Data Center (NEPDC) was established with Tim Mutch as its Director. The Center was originally located in the Sciences Library due to space limitations but moved to the Lincoln Field Building in 1983 where it could serve the Planetary Group and outside visitors more effectively. In 1984 Dr. Peter Schultz moved to Brown University and became its Director after serving in a similar capacity at the Lunar and Planetary Institute since 1976. Debbie Glavin has served as the Data Center Coordinator since 1982. Initially the NEPDC was build around Tim Mutch's research collection of Lunar Orbiter and Mariner 9 images with only partial sets of Apollo and Viking materials. Its collection was broadened and deepened as the Director (PHS) searched for materials to fill in gaps. Two important acquisitions included the transfer of a Viking collection from a previous PI in Tucson and the donation of surplused lunar materials (Apollo) from the USGS/Menlo Park prior to its building being torn down. Later additions included the pipeline of distributed materials such as the Viking photomosaic series and certain Magellan products. Not all materials sent to Brown, however, found their way to the Data Center, e.g., Voyager prints and negatives. In addition to the NEPDC, the planetary research collection is separately maintained in conjunction with past and ongoing mission activities. These materials (e.g., Viking, Magellan, Galileo, MGS mission products) are housed elsewhere and maintained independently from the NEPDC. They are unavailable to other researchers, educators, and general public. Consequently, the NEPDC represents the only generally accessible reference collection for use by researchers, students, faculty, educators, and general public in the Northeast corridor.

  10. Precision photometry for planetary transits

    CERN Document Server

    Pont, F; Pont, Frederic; Moutou, Claire

    2007-01-01

    We review the state of the art in follow-up photometry for planetary transit searches. Three topics are discussed: (1) Photometric monitoring of planets discovered by radial velocity to detect possible transits (2) Follow-up photometry of candidates from photometric transit searches to weed out eclipsing binaries and false positives (3) High-precision lightcurves of known transiting planets to increase the accuracy on the planet parameters.

  11. Mars 2020 Planetary Protection Status

    Science.gov (United States)

    Stricker, Moogega; Bernard, Douglas; Benardini, James Nick; Jones, Melissa

    2016-07-01

    The Mars 2020 (M2020) flight system consists of a cruise stage; an entry, descent and landing system (EDL); and a Radioisotope Thermoelectric Generator (RTG) powered roving science vehicle that will land on the surface of Mars. The M2020 Mission is designed to investigate key question related to the habitability of Mars and will conduct assessments that set the stage for potential future human exploration of Mars. Per its Program Level Requirements, the project will also acquire and cache samples of rock, regolith, and/or procedural "blank" samples for possible return to Earth by a subsequent mission. NASA has assigned the M2020 Mission as a Category V Restricted Earth Return due to the possible future return of collected samples. As indicated in NPR8020.12D, Section 5.3.3.2, the outbound leg of a Category V mission that could potentially return samples to Earth, Mars 2020 would be expected to meet the requirements of a Category IVb mission. The entire flight system is subject to microbial reduction requirements, with additional specific emphasis on the sample acquisition and caching. A bioburden accounting tool is being used to track the microbial population on the surfaces to ensure that the biological cleanliness requirements are met. Initial bioburden estimates based on MSL heritage allows M2020 to gauge more precisely how the bioburden is allocated throughout each hardware element. Mars 2020 has completed a Planetary Protection Plan with Planetary Implementation Plans at a mature draft form. Planetary protection sampling activities have commenced with the start of flight system fabrication and assembly. The status of the Planetary Protection activities will be reported.

  12. A method to estimate optical distortion using planetary images

    Science.gov (United States)

    Kouyama, Toru; Yamazaki, Atsushi; Yamada, Manabu; Imamura, Takeshi

    2013-09-01

    We developed a method to calibrate optical distortion parameters for axisymmetrical optical systems using images of a spherical target taken at a variety of distances. The method utilizes the fact that the influence of distortion on the apparent radius in the image changes with the disk size of the projected body. Because several planets can be used as the spherical target, this method enables us to obtain distortion parameters in space and by using a large number of planetary images, desired accuracy of parameters can be achieved statistically. The applicability of the method was tested by applying it to simulated planetary images and real Venus images taken by Venus Monitoring Camera onboard the ESA's Venus Express, and optical distortion was successfully retrieved with the pixel position error of less than 1 pixel. Venus is the planet most suitable for the proposed method because of its smooth, nearly spherical surface of the haze layer covering the planet.

  13. Planetary space weather: scientific aspects and future perspectives

    Science.gov (United States)

    Plainaki, Christina; Lilensten, Jean; Radioti, Aikaterini; Andriopoulou, Maria; Milillo, Anna; Nordheim, Tom A.; Dandouras, Iannis; Coustenis, Athena; Grassi, Davide; Mangano, Valeria; Massetti, Stefano; Orsini, Stefano; Lucchetti, Alice

    2016-08-01

    In this paper, we review the scientific aspects of planetary space weather at different regions of our Solar System, performing a comparative planetology analysis that includes a direct reference to the circum-terrestrial case. Through an interdisciplinary analysis of existing results based both on observational data and theoretical models, we review the nature of the interactions between the environment of a Solar System body other than the Earth and the impinging plasma/radiation, and we offer some considerations related to the planning of future space observations. We highlight the importance of such comparative studies for data interpretations in the context of future space missions (e.g. ESA JUICE; ESA/JAXA BEPI COLOMBO). Moreover, we discuss how the study of planetary space weather can provide feedback for better understanding the traditional circum-terrestrial space weather. Finally, a strategy for future global investigations related to this thematic is proposed.

  14. Transient chaos and fractal structures in planetary feeding zones

    CERN Document Server

    Kovács, Tamás

    2014-01-01

    The circular restricted three body problem is investigated in the context of accretion and scattering processes. In our model a large number of identical non-interacting mass-less planetesimals are considered in planar case orbiting a star-planet system. This description allows us to investigate in dynamical systems approach the gravitational scattering and possible captures of the particles by the forming planetary embryo. Although the problem serves a large variety of complex motion, the results can be easily interpreted because of the low dimensionality of the phase space. We show that initial conditions define isolated regions of the disk, where accretion or escape of the planetesimals occur, these have, in fact, a fractal structure. The fractal geometry of these "basins" implies that the dynamics is very complex. Based on the calculated escape rates and escape times, it is also demonstrated that the planetary accretion rate is exponential for short times and follows a power-law for longer integration. A ...

  15. Chondrule Formation via Impact Jetting Triggered by Planetary Accretion

    CERN Document Server

    Hasegawa, Yasuhiro; Matsumoto, Yuji; Oshino, Shoichi

    2015-01-01

    Chondrules are one of the most primitive elements that can serve as a fundamental clue as to the origin of our Solar system. We investigate a formation scenario of chondrules that involves planetesimal collisions and the resultant impact jetting. Planetesimal collisions are the main agent to regulate planetary accretion that corresponds to the formation of terrestrial planets and cores of gas giants. The key component of this scenario is that ejected materials can melt when the impact velocity between colliding planetesimals exceeds about 2.5 km s$^{-1}$. The previous simulations show that the process is efficient enough to reproduce the primordial abundance of chondrules. We examine this scenario carefully by performing semi-analytical calculations that are developed based on the results of direct $N$-body simulations. As found by the previous work, we confirm that planetesimal collisions that occur during planetary accretion can play an important role in forming chondrules. This arises because protoplanet-p...

  16. PHL 932: when is a planetary nebula not a planetary nebula?

    CERN Document Server

    Frew, David J; O'Toole, Simon J; Parker, Quentin A

    2009-01-01

    The emission nebula around the subdwarf B (sdB) star PHL 932 is currently classified as a planetary nebula (PN) in the literature. Based on a large body of multi-wavelength data, both new and previously published, we show here that this low-excitation nebula is in fact a small Stromgren sphere (HII region) in the interstellar medium around this star. We summarise the properties of the nebula and its ionizing star, and discuss its evolutionary status. We find no compelling evidence for close binarity, arguing that PHL 932 is an ordinary sdB star. We also find that the emission nebulae around the hot DO stars PG 0108+101 and PG 0109+111 are also Stromgren spheres in the ISM, and along with PHL 932, are probably associated with the same extensive region of high-latitude molecular gas in Pisces-Pegasus.

  17. Autonomous planetary rover at Carnegie Mellon

    Science.gov (United States)

    Whittaker, William; Kanade, Takeo; Mitchell, Tom

    1990-01-01

    This report describes progress in research on an autonomous robot for planetary exploration. In 1989, the year covered by this report, a six-legged walking robot, the Ambler, was configured, designed, and constructed. This configuration was used to overcome shortcomings exhibited by existing wheeled and walking robot mechanisms. The fundamental advantage of the Ambler is that the actuators for body support are independent of those for propulsion; a subset of the planar joints propel the body, and the vertical actuators support and level the body over terrain. Models of the Ambler's dynamics were developed and the leveling control was studied. An integrated system capable of walking with a single leg over rugged terrain was implemented and tested. A prototype of an Ambler leg is suspended below a carriage that slides along rails. To walk, the system uses a laser scanner to find a clear, flat foothold, positions the leg above the foothold, contacts the terrain with the foot, and applies force enough to advance the carriage along the rails. Walking both forward and backward, the system has traversed hundreds of meters of rugged terrain including obstacles too tall to step over, trenches too deep to step in, closely spaced rocks, and sand hills. In addition, preliminary experiments were conducted with concurrent planning and execution, and a leg recovery planner that generates time and power efficient 3D trajectories using 2D search was developed. A Hero robot was used to demonstrate mobile manipulation. Indoor tasks include collecting cups from the lab floor, retrieving printer output, and recharging when its battery gets low. The robot monitors its environment, and handles exceptional conditions in a robust fashion, using vision to track the appearance and disappearance of cups, onboard sonars to detect imminent collisions, and monitors to detect the battery level.

  18. Verification of a Monte-Carlo planetary surface radiation environment model using γ-ray data from Lunar Prospector and 2001 Mars Odyssey

    International Nuclear Information System (INIS)

    Characterising a planetary radiation environment is important to: (1) assess the habitability of a planetary body for indigenous life; (2) assess the risks associated with manned exploration missions to a planetary body and (3) predict/interpret the results that remote sensing instrumentation may obtain from a planetary body (e.g. interpret the γ-ray emissions from a planetary surface produced by radioactive decay or via the interaction of galactic cosmic rays to obtain meaningful estimates of the concentration of certain elements on the surface of a planet). The University of Leicester is developing instrumentation for geophysical applications that include γ-ray spectroscopy, γ-ray densitometry and radiometric dating. This paper describes the verification of a Monte-Carlo planetary radiation environment model developed using the MCNPX code. The model is designed to model the radiation environments of Mars and the Moon, but is applicable to other planetary bodies, and will be used to predict the performance of the instrumentation being developed at Leicester. This study demonstrates that the modelled γ-ray data is in good agreement with γ-ray data obtained by the γ-ray spectrometers on 2001 Mars Odyssey and Lunar Prospector, and can be used to accurately model geophysical instrumentation for planetary science applications.

  19. Verification of a Monte-Carlo planetary surface radiation environment model using gamma-ray data from Lunar Prospector and 2001 Mars Odyssey

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, M.S., E-mail: mss16@star.le.ac.u [Space Research Centre, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); Ambrosi, R.M. [Space Research Centre, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom)

    2010-01-01

    Characterising a planetary radiation environment is important to: (1) assess the habitability of a planetary body for indigenous life; (2) assess the risks associated with manned exploration missions to a planetary body and (3) predict/interpret the results that remote sensing instrumentation may obtain from a planetary body (e.g. interpret the gamma-ray emissions from a planetary surface produced by radioactive decay or via the interaction of galactic cosmic rays to obtain meaningful estimates of the concentration of certain elements on the surface of a planet). The University of Leicester is developing instrumentation for geophysical applications that include gamma-ray spectroscopy, gamma-ray densitometry and radiometric dating. This paper describes the verification of a Monte-Carlo planetary radiation environment model developed using the MCNPX code. The model is designed to model the radiation environments of Mars and the Moon, but is applicable to other planetary bodies, and will be used to predict the performance of the instrumentation being developed at Leicester. This study demonstrates that the modelled gamma-ray data is in good agreement with gamma-ray data obtained by the gamma-ray spectrometers on 2001 Mars Odyssey and Lunar Prospector, and can be used to accurately model geophysical instrumentation for planetary science applications.

  20. Institute of Geophysics, Planetary Physics, and Signatures

    Data.gov (United States)

    Federal Laboratory Consortium — The Institute of Geophysics, Planetary Physics, and Signatures at Los Alamos National Laboratory is committed to promoting and supporting high quality, cutting-edge...

  1. Nasa's Planetary Geologic Mapping Program: Overview

    Science.gov (United States)

    Williams, D. A.

    2016-06-01

    NASA's Planetary Science Division supports the geologic mapping of planetary surfaces through a distinct organizational structure and a series of research and analysis (R&A) funding programs. Cartography and geologic mapping issues for NASA's planetary science programs are overseen by the Mapping and Planetary Spatial Infrastructure Team (MAPSIT), which is an assessment group for cartography similar to the Mars Exploration Program Assessment Group (MEPAG) for Mars exploration. MAPSIT's Steering Committee includes specialists in geological mapping, who make up the Geologic Mapping Subcommittee (GEMS). I am the GEMS Chair, and with a group of 3-4 community mappers we advise the U.S. Geological Survey Planetary Geologic Mapping Coordinator (Dr. James Skinner) and develop policy and procedures to aid the planetary geologic mapping community. GEMS meets twice a year, at the Annual Lunar and Planetary Science Conference in March, and at the Annual Planetary Mappers' Meeting in June (attendance is required by all NASA-funded geologic mappers). Funding programs under NASA's current R&A structure to propose geological mapping projects include Mars Data Analysis (Mars), Lunar Data Analysis (Moon), Discovery Data Analysis (Mercury, Vesta, Ceres), Cassini Data Analysis (Saturn moons), Solar System Workings (Venus or Jupiter moons), and the Planetary Data Archiving, Restoration, and Tools (PDART) program. Current NASA policy requires all funded geologic mapping projects to be done digitally using Geographic Information Systems (GIS) software. In this presentation we will discuss details on how geologic mapping is done consistent with current NASA policy and USGS guidelines.

  2. Sealed Planetary Return Canister (SPRC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample return missions have primary importance in future planetary missions. A basic requirement is that samples be returned in pristine, uncontaminated condition,...

  3. Robotic Tool Changer for Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future planetary exploration missions will require compact, lightweight robotic manipulators for handling a variety of tools & instruments without increasing...

  4. Teaching, learning, and planetary exploration

    Science.gov (United States)

    Brown, Robert A.

    1992-01-01

    The progress accomplished in the first five months of the three-year grant period of Teaching, Learning, and Planetary Exploration is presented. The objectives of this project are to discover new education products and services based on space science, particularly planetary exploration. An Exploration in Education is the umbrella name for the education projects as they are seen by teachers and the interested public. As described in the proposal, our approach consists of: (1) increasing practical understanding of the potential role and capabilities of the research community to contribute to basic education using new discoveries; (2) developing an intellectual framework for these contributions by supplying criteria and templates for the teacher's stories; (3) attracting astronomers, engineers, and technical staff to the project and helping them form productive education partnerships for the future, (4) exploring relevant technologies and networks for authoring and communicating the teacher's stories; (5) enlisting the participation of potential user's of the teacher's stories in defining the products; (6) actually producing and delivering many educationally useful teacher's stories; and (7) reporting the pilot study results with critical evaluation. Technical progress was made by assembling our electronic publishing stations, designing electronic publications based on space science, and developing distribution approaches for electronic products. Progress was made addressing critical issues by developing policies and procedures for securing intellectual property rights and assembling a focus group of teachers to test our ideas and assure the quality of our products. The following useful materials are being produced: the TOPS report; three electronic 'PictureBooks'; one 'ElectronicArticle'; three 'ElectronicReports'; ten 'PrinterPosters'; and the 'FaxForum' with an initial complement of printed materials. We have coordinated with planetary scientists and astronomers

  5. Teaching, learning, and planetary exploration

    Science.gov (United States)

    Brown, Robert A.

    1992-12-01

    The progress accomplished in the first five months of the three-year grant period of Teaching, Learning, and Planetary Exploration is presented. The objectives of this project are to discover new education products and services based on space science, particularly planetary exploration. An Exploration in Education is the umbrella name for the education projects as they are seen by teachers and the interested public. As described in the proposal, our approach consists of: (1) increasing practical understanding of the potential role and capabilities of the research community to contribute to basic education using new discoveries; (2) developing an intellectual framework for these contributions by supplying criteria and templates for the teacher's stories; (3) attracting astronomers, engineers, and technical staff to the project and helping them form productive education partnerships for the future, (4) exploring relevant technologies and networks for authoring and communicating the teacher's stories; (5) enlisting the participation of potential user's of the teacher's stories in defining the products; (6) actually producing and delivering many educationally useful teacher's stories; and (7) reporting the pilot study results with critical evaluation. Technical progress was made by assembling our electronic publishing stations, designing electronic publications based on space science, and developing distribution approaches for electronic products. Progress was made addressing critical issues by developing policies and procedures for securing intellectual property rights and assembling a focus group of teachers to test our ideas and assure the quality of our products. The following useful materials are being produced: the TOPS report; three electronic 'PictureBooks'; one 'ElectronicArticle'; three 'ElectronicReports'; ten 'PrinterPosters'; and the 'FaxForum' with an initial complement of printed materials. We have coordinated with planetary scientists and astronomers

  6. New Indivisible Planetary Science Paradigm

    OpenAIRE

    Herndon, J. Marvin

    2013-01-01

    I present here a new, indivisible planetary science paradigm, a wholly self-consistent vision of the nature of matter in the Solar System, and dynamics and energy sources of planets. Massive-core planets formed by condensing and raining-out from within giant gaseous protoplanets at high pressures and high temperatures. Earth's complete condensation included a 300 Earth-mass gigantic gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter. T-Tauri eruptions stri...

  7. Zinc abundances of planetary nebulae

    OpenAIRE

    Smith, Christina L.; Zijlstra, Albert A.; Dinerstein, Harriet L.

    2014-01-01

    Zinc is a useful surrogate element for measuring Fe/H as, unlike iron, it is not depleted in the gas phase media. Zn/H and O/Zn ratios have been derived using the [Zn IV] emission line at 3.625um for a sample of nine Galactic planetary nebulae, seven of which are based upon new observations using the VLT. Based on photoionization models, O/O++ is the most reliable ionisation correction factor for zinc that can readily be determined from optical emission lines, with an estimated accuracy of 10...

  8. Pioneering Concepts of Planetary Habitability

    Science.gov (United States)

    Raulin Cerceau, Florence

    Famous astronomers such as Richard A. Proctor (1837-1888), Jules Janssen (1824-1907), and Camille Flammarion (1842-1925) studied the concept of planetary habitability a century before this concept was updated in the context of the recent discoveries of exoplanets and the development of planetary exploration in the solar system. They independently studied the conditions required for other planets to be inhabited, and these considerations led them to specify the term "habitability." Naturally, the planet Mars was at the heart of the discussion. Our neighboring planet, regarded as a sister planet of Earth, looked like a remarkable abode for life. During the second part of the nineteenth century, the possibility of Martian intelligent life was intensively debated, and hopes were still ardent to identify a kind of vegetation specific to the red planet. In such a context, the question of Mars' habitability seemed to be very valuable, especially when studying hypothetical Martian vegetation. At the dawn of the Space Age, German-born physician and pioneer of space medicine Hubertus Strughold (1898-1987) proposed in the book The Green and Red Planet: A Physiological Study of the Possibility of Life on Mars (1954) to examine the planets of the solar system through a "planetary ecology." This innovative notion, which led to a fresh view of the concept of habitability, was supposed to designate a new field involving biology: "the science of planets as an environment for life" (Strughold 1954). This notion was very close to the concept of habitability earlier designated by our nineteenth-century pioneers. Strughold also coined the term "ecosphere" to name the region surrounding a star where conditions allowed life-bearing planets to exist. We highlight in this chapter the historical aspects of the emergence of the (modern) concept of habitability. We will consider the different formulations proposed by the pioneers, and we will see in what way it can be similar to our

  9. MOA-2010-BLG-311: A planetary candidate below the threshold of reliable detection

    CERN Document Server

    Yee, J C; Bond, I A; Allen, W; Monard, L A G; Albrow, M D; Fouque, P; Dominik, M; Tsapras, Y; Udalski, A; Gould, A; Zellem, R; MicroFUN, the; MOA,; OGLE,; PLANET,

    2012-01-01

    We analyze MOA-2010-BLG-311, a high magnification (A_max>600) microlensing event with complete data coverage over the peak, making it very sensitive to planetary signals. We fit this event with both a point lens and a 2-body lens model and find that the 2-body lens model is a better fit but with only Delta chi^2~140. The preferred mass ratio between the lens star and its companion is $q=10^(-3.7+/-0.1), placing the candidate companion in the planetary regime. Despite the formal significance of the planet, we show that because of systematics in the data the evidence for a planetary companion to the lens is too tenuous to claim a secure detection. When combined with analyses of other high-magnification events, this event helps empirically define the threshold for reliable planet detection in high-magnification events, which remains an open question.

  10. MOA-2010-BLG-311: A PLANETARY CANDIDATE BELOW THE THRESHOLD OF RELIABLE DETECTION

    International Nuclear Information System (INIS)

    We analyze MOA-2010-BLG-311, a high magnification (Amax > 600) microlensing event with complete data coverage over the peak, making it very sensitive to planetary signals. We fit this event with both a point lens and a two-body lens model and find that the two-body lens model is a better fit but with only Δχ2 ∼ 80. The preferred mass ratio between the lens star and its companion is q = 10–3.7±0.1, placing the candidate companion in the planetary regime. Despite the formal significance of the planet, we show that because of systematics in the data the evidence for a planetary companion to the lens is too tenuous to claim a secure detection. When combined with analyses of other high-magnification events, this event helps empirically define the threshold for reliable planet detection in high-magnification events, which remains an open question.

  11. MOA-2010-BLG-311: A PLANETARY CANDIDATE BELOW THE THRESHOLD OF RELIABLE DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Yee, J. C.; Hung, L.-W.; Gould, A.; Gaudi, B. S. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Bond, I. A. [Institute for Information and Mathematical Sciences, Massey University, Private Bag 102-904, Auckland 1330 (New Zealand); Allen, W. [Vintage Lane Observatory, Blenheim (New Zealand); Monard, L. A. G. [Bronberg Observatory, Centre for Backyard Astrophysics, Pretoria (South Africa); Albrow, M. D. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch 8020 (New Zealand); Fouque, P. [IRAP, CNRS, Universite de Toulouse, 14 avenue Edouard Belin, F-31400 Toulouse (France); Dominik, M. [SUPA, University of St. Andrews, School of Physics and Astronomy, North Haugh, St. Andrews, KY16 9SS (United Kingdom); Tsapras, Y. [Las Cumbres Observatory Global Telescope Network, 6740B Cortona Drive, Goleta, CA 93117 (United States); Udalski, A. [Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland); Zellem, R. [Department of Planetary Sciences/LPL, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721 (United States); Bos, M. [Molehill Astronomical Observatory, North Shore City, Auckland (New Zealand); Christie, G. W. [Auckland Observatory, P.O. Box 24-180, Auckland (New Zealand); DePoy, D. L. [Department of Physics, Texas A and M University, 4242 TAMU, College Station, TX 77843-4242 (United States); Dong, Subo [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Drummond, J. [Possum Observatory, Patutahi (New Zealand); Gorbikov, E. [School of Physics and Astronomy, Raymond and Beverley Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978 (Israel); Han, C., E-mail: liweih@astro.ucla.edu, E-mail: rzellem@lpl.arizona.edu, E-mail: tim.natusch@aut.ac.nz [Department of Physics, Chungbuk National University, 410 Seongbong-Rho, Hungduk-Gu, Chongju 371-763 (Korea, Republic of); Collaboration: muFUN Collaboration; MOA Collaboration; OGLE Collaboration; PLANET Collaboration; RoboNet Collaboration; MiNDSTEp Consortium; and others

    2013-05-20

    We analyze MOA-2010-BLG-311, a high magnification (A{sub max} > 600) microlensing event with complete data coverage over the peak, making it very sensitive to planetary signals. We fit this event with both a point lens and a two-body lens model and find that the two-body lens model is a better fit but with only {Delta}{chi}{sup 2} {approx} 80. The preferred mass ratio between the lens star and its companion is q = 10{sup -3.7{+-}0.1}, placing the candidate companion in the planetary regime. Despite the formal significance of the planet, we show that because of systematics in the data the evidence for a planetary companion to the lens is too tenuous to claim a secure detection. When combined with analyses of other high-magnification events, this event helps empirically define the threshold for reliable planet detection in high-magnification events, which remains an open question.

  12. Shape and topography corrections for planetary nuclear spectroscopy

    Science.gov (United States)

    Prettyman, Thomas H.; Hendricks, John S.

    2015-11-01

    The elemental composition of planetary surfaces can be determined using gamma ray and neutron spectroscopy. Most planetary bodies for which nuclear spectroscopy data have been acquired are round, and simple, analytic corrections for measurement geometry can be applied; however, recent measurements of the irregular asteroid 4 Vesta by Dawn required more detailed corrections using a shape model (Prettyman et al., Science 2012). In addition, subtle artifacts of topography have been observed in low altitude measurements of lunar craters, with potential implications for polar hydrogen content (Eke et al., JGR 2015). To explore shape and topography effects, we have updated the general-purpose Monte Carlo radiation transport code MCNPX to include a polygonal shape model (Prettyman and Hendricks, LPSC 2015). The shape model is fully integrated with the code’s 3D combinatorial geometry modules. A voxel-based acceleration algorithm enables fast ray-intersection calculations needed for Monte Carlo. As modified, MCNPX can model neutron and gamma ray transport within natural surfaces using global and/or regional shape/topography data (e.g. from photogrammetry and laser altimetry). We are using MCNPX to explore the effect of small-scale roughness, regional-, and global-topography for asteroids, comets and close-up measurements of high-relief features on larger bodies, such as the lunar surface. MCNPX can characterize basic effects on measurements by an orbiting spectrometer such as 1) the angular distribution of emitted particles, 2) shielding of galactic cosmic rays by surrounding terrain and 3) re-entrant scattering. In some cases, re-entrant scattering can be ignored, leading to a fast ray-tracing model that treats effects 1 and 2. The algorithm is applied to forward modeling and spatial deconvolution of epithermal neutron data acquired at Vesta. Analyses of shape/topography effects and correction strategies are presented for Vesta, selected small bodies and cratered

  13. A Laser Altimeter for a Planetary Flyby Mission

    Science.gov (United States)

    Smith, D. E.; Zuber, M. T.; Sun, X.; Cavanaugh, J.; Neumann, G. A.; Mazarico, E.; Genova, A.

    2014-12-01

    Several planetary missions are contemplated as flybys of planets, asteroids, and natural satellites. In many cases the option to orbit the body is impractical and observations during one or many flybys represent the only reasonable option. A laser altimeter provides measurements of topography and shape, surface roughness, and normal reflectivity at the laser wavelength and has been shown to be very effective at Mars, Mercury and the Moon when in orbit about the body and also when in proximity of an asteroid. But flyby missions are less able to provide the coverage and uniformity of the data being acquired by the instruments on the s/c because of the variation in range of the spacecraft from the body during a flyby. To address this problem, we have modified the design of our single beam Mercury Laser Altimeter (MLA), currently collecting observations on the MESSENGER mission, to provide an operating range of several thousand kilometers by increasing the output from the laser, providing a variable pulse-rate while maintaining constant electrical power, that can provide quasi-contiguous altimeter pixels during the flyby, and by storing the complete output from the detector. This approach will provide accurate topographic and shape data and enable improved orbit determination of the spacecraft by the use of orbital crossovers with minimal interpolation errors between measurements. The mass, power and data rate of the instrument is compatible with typical constraints in planetary missions.

  14. Theory of Planetary System Formation

    Science.gov (United States)

    Cassen, Patrick

    1996-01-01

    Observations and theoretical considerations support the idea that the Solar System formed by the collapse of tenuous interstellar matter to a disk of gas and dust (the primitive solar nebula), from which the Sun and other components separated under the action of dissipative forces and by the coagulation of solid material. Thus, planets are understood to be contemporaneous byproducts of star formation. Because the circumstellar disks of new stars are easier to observe than mature planetary systems, the possibility arises that the nature and variety of planets might be studied from observations of the conditions of their birth. A useful theory of planetary system formation would therefore relate the properties of circumstellar disks both to the initial conditions of star formation and to the consequent properties of planets to those of the disk. Although the broad outlines of such a theory are in place, many aspects are either untested, controversial, or otherwise unresolved; even the degree to which such a comprehensive theory is possible remains unknown.

  15. New Indivisible Planetary Science Paradigm

    CERN Document Server

    Herndon, J Marvin

    2013-01-01

    I present here a new, indivisible planetary science paradigm, a wholly self-consistent vision of the nature of matter in the Solar System, and dynamics and energy sources of planets. Massive-core planets formed by condensing and raining-out from within giant gaseous protoplanets at high pressures and high temperatures. Earth's complete condensation included a 300 Earth-mass gigantic gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter. T-Tauri eruptions stripped the gases away from the inner planets and stripped a portion of Mercury's incompletely condensed protoplanet, and transported it to the region between Mars and Jupiter where it fused with in-falling oxidized condensate from the outer regions of the Solar System and formed the parent matter of ordinary chondrite meteorites, the main-Belt asteroids, and veneer for the inner planets, especially Mars. In response to decompression-driven planetary volume increases, cracks form to increase surface area and mountain ranges ...

  16. Visual lunar and planetary astronomy

    CERN Document Server

    Abel, Paul G

    2013-01-01

    With the advent of CCDs and webcams, the focus of amateur astronomy has to some extent shifted from science to art. The object of many amateur astronomers is now to produce “stunning images” that, although beautiful, are not intended to have scientific merit. Paul Abel has been addressing this issue by promoting visual astronomy wherever possible – at talks to astronomical societies, in articles for popular science magazines, and on BBC TV’s The Sky at Night.   Visual Lunar and Planetary Astronomy is a comprehensive modern treatment of visual lunar and planetary astronomy, showing that even in the age of space telescopes and interplanetary probes it is still possible to contribute scientifically with no more than a moderately priced commercially made astronomical telescope.   It is believed that imaging and photography is somehow more objective and more accurate than the eye, and this has led to a peculiar “crisis of faith” in the human visual system and its amazing processing power. But by anal...

  17. Interactive investigations into planetary interiors

    Science.gov (United States)

    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.

  18. Laboratory Spectroscopy of Planetary Molecules

    Science.gov (United States)

    Brown, L.; Orton, G.

    2007-08-01

    An international team of laboratory spectroscopists are working in concert to support remote sensing of planetary atmospheres and Titan. An overview of high resolution laboratory investigations will be presented for spectral bands from the rotational wavelengths into the near infrared. The studies include measurements and theoretical analyses of the line positions, intensities and/or broadening coefficients needed to improve the spectroscopic databases required for planetary applications. The molecular studies include water (H2O) broadened by carbon dioxide in the far- and mid- infrared; positions, intensities, broadening and line mixing of carbon dioxide (CO2) in the near-IR; broadening and line mixing of methane in the mid- and near-IR; frequencies of methyl cyanide (CH3CN) in the rotational region and line positions, intensities and nitrogen broadening of methyl cyanide in the low fundamental bands; global theoretical modeling of the phosphine (PH3) parameters; and frequencies of acetaldehyde (CH3CHO), methylamine (CH3NH2) and deuterated acetylene (HCCD, DCCD) in the rotational region.

  19. Planetary Environments: Scientific Issues and Perspectives

    Directory of Open Access Journals (Sweden)

    Encrenaz Th.

    2014-02-01

    Full Text Available What are the planetary environments where conditions are best suited for habitability? A first constraint is provided by the presence of liquid water. This condition allows us to define two kinds of media: (1 the atmospheres of solid (exoplanets with a temperature typically ranging between 0°C and 100°C, and (2 the interiors of icy bodies (outer satellites or possibly exosatellites where the pressure and temperature would fit the liquid phase region of the water phase diagram. In the case of Mars, significant progress has been achieved about our understanding of the history of liquid water in the past, thanks to the findings of recent space missions. The study of the outer satellites is also benefiting from the on-going operation of the Cassini mission. In the case of exopl nets, new discoveries are continuously reported, especially with the Kepler mission, in operation since 2009. With the emergence of transit spectroscopy, a new phase of exoplanets’ exploration has started, their characterization, opening the new field of exoplanetology. In the future, new perspectives appear regarding the exploration of Mars, the giant planets and exoplanets, with the ultimate goal of characterizing the atmospheres of temperate exoplanets.

  20. Kelvin Helmholtz Instability in Planetary Magnetospheres

    Science.gov (United States)

    Johnson, Jay R.; Wing, Simon; Delamere, Peter A.

    2014-11-01

    Kelvin-Helmholtz instability plays a particularly important role in plasma transport at magnetospheric boundaries because it can control the development of a turbulent boundary layer, which governs the transport of mass, momentum, and energy across the boundary. Waves generated at the interface can also couple into body modes in the plasma sheet and inner magnetosphere where they can play an important role in plasma sheet transport and particle energization in the inner magnetosphere. Kinetic and electron-scale effects are important for the development of K-H instability, leading to secondary instabilities and plasma mixing. The development of vortices that entwine magnetosheath field lines with magnetospheric field lines also allows reconnection and the interchange of plasma blobs from open to closed field lines. Dawn-dusk asymmetries in Kelvin-Helmholtz development at planetary boundary layers may result from several effects including plasma corotation, kinetic effects, magnetic geometry, or asymmetric distribution of plasma. Examples are provided throughout the solar system illustrating the pervasive effects of the Kelvin-Helmholtz instability on plasma transport.

  1. Review on the Role of Planetary Factors on Habitability

    Science.gov (United States)

    Kereszturi, A.; Noack, L.

    2016-07-01

    In this work various factors on the habitability were considered, focusing on conditions irrespective of the central star's radiation, to see the role of specific planetary body related effects. These so called planetary factors were evaluated to identify those trans-domain issues where important information is missing but good chance exit to be filled by new knowledge that might be gained in the next decade(s). Among these strategic knowledge gaps, specific issues are listed, like occurrence of radioactive nucleides in star forming regions, models to estimate the existence of subsurface liquid water from bulk parameters plus evolutionary context of the given system, estimation on the existence of redox gradient depending on the environment type etc. These issues require substantial improvement of modelling and statistical handling of various cases, as "planetary environment types". Based on our current knowledge it is probable that subsurface habitability is at least as frequent, or more frequent than surface habitability. Unfortunately it is more difficult from observations to infer conditions for subsurface habitability, but specific argumentation might help with indirect ways, which might result in new methods to approach habitability in general.

  2. On Some General Regularities of Formation of the Planetary Systems

    Directory of Open Access Journals (Sweden)

    Belyakov A. V.

    2014-01-01

    Full Text Available J.Wheeler’s geometrodynamic concept has been used, in which space continuum is considered as a topologically non-unitary coherent surface admitting the existence of transitions of the input-output kind between distant regions of the space in an additional dimension. This model assumes the existence of closed structures (micro- and macro- contours formed due to the balance between main interactions: gravitational, electric, magnetic, and inertial forces. It is such macrocontours that have been demonstrated to form — independently of their material basis — the essential structure of objects at various levels of organization of matter. On the basis of this concept in this paper basic regularities acting during formation planetary systems have been obtained. The existence of two sharply different types of planetary systems has been determined. The dependencies linking the masses of the planets, the diameters of the planets, the orbital radii of the planet, and the mass of the central body have been deduced. The possibility of formation of Earth-like planets near brown dwarfs has been grounded. The minimum mass of the planet, which may arise in the planetary system, has been defined.

  3. Stability of Satellites in Closely Packed Planetary Systems

    CERN Document Server

    Payne, Matthew J; Holman, Matthew J; Perets, Hagai B

    2013-01-01

    We perform numerical integrations of four-body (star, planet, planet, satellite) systems to investigate the stability of satellites in planetary Systems with Tightly-packed Inner Planets (STIPs). We find that the majority of closely-spaced stable two-planet systems can stably support satellites across a range of parameter-space which is only slightly decreased compared to that seen for the single-planet case. In particular, circular prograde satellites remain stable out to $\\sim 0.4 R_H$ (where $R_H$ is the Hill Radius) as opposed to $\\sim 0.5 R_H$ in the single-planet case. A similarly small restriction in the stable parameter-space for retrograde satellites is observed, where planetary close approaches in the range 2.5 to 4.5 mutual Hill radii destabilize most satellites orbits only if $a\\sim 0.65 R_H$. In very close planetary pairs (e.g. the 12:11 resonance) the addition of a satellite frequently destabilizes the entire system, causing extreme close-approaches and the loss of satellites over a range of cir...

  4. Disks around stars and the growth of planetary systems.

    Science.gov (United States)

    Greaves, Jane S

    2005-01-01

    Circumstellar disks play a vital evolutionary role, providing a way to move gas inward and onto a young star. The outward transfer of angular momentum allows the star to contract without breaking up, and the remnant disk of gas and particles is the reservoir for forming planets. High-resolution spectroscopy is uncovering planetary dynamics and motion within the remnant disk, and imaging at infrared to millimeter wavelengths resolves disk structure over billions of years of evolution. Most stars are born with a disk, and models of planet formation need to form such bodies from the disk material within the disk's 10-million-year life-span. PMID:15637266

  5. Hydromagnetic quasi-geostrophic modes in rapidly rotating planetary cores

    CERN Document Server

    Canet, Elisabeth; Fournier, Alexandre

    2014-01-01

    The core of a terrestrial-type planet consists of a spherical shell of rapidly rotating, electrically conducting, fluid. Such a body supports two distinct classes of quasi-geostrophic eigenmodes: fast, primarily hydrodynamic, inertial modes with period related to the rotation time scale and slow, primarily magnetic, magnetostrophic modes with much longer periods. Here, we investigate the properties of these hydromagnetic quasi-geostrophic modes as a function of non-dimensional parameters controlling the strength of the background magnetic field, the planetary rotation rate, and the amount of magnetic dissipation. ... read full length abstract in the paper.

  6. Dynamics of Populations of Planetary Systems (IAU C197)

    Science.gov (United States)

    Knezevic, Zoran; Milani, Andrea

    2005-05-01

    1. Resonances and stability of extra-solar planetary systems C. Beaugé, N. Callegari, S. Ferraz-Mello and T. A. Michtchenko; 2. Formation, migration, and stability of extrasolar planetary systems Fred C. Adams; 3. Dynamical evolution of extrasolar planetary systems Ji-Lin Zhou and Yi-Sui Sun; 4. Dynamics of planetesimals: the role of two-body relaxation Eiichiro Kokubo; 5. Fitting orbits Andrzej J. Maciejewski, Krzysztof Gozdziewski and Szymon Kozlowski; 6. The secular planetary three body problem revisited Jacques Henrard and Anne-Sophie Libert; 7. Dynamics of extrasolar systems at the 5/2 resonance: application to 47 UMa Dionyssia Psychoyos and John D. Hadjidemetriou; 8. Our solar system as model for exosolar planetary systems Rudolf Dvorak, Áron Süli and Florian Freistetter; 9. Planetary motion in double stars: the influence of the secondary Elke Pilat-Lohinger; 10. Planetary orbits in double stars: influence of the binary's orbital eccentricity Daniel Benest and Robert Gonczi; 11. Astrometric observations of 51 Peg and Gliese 623 at Pulkovo observatory with 65 cm refractor N. A. Shakht; 12. Observations of 61 Cyg at Pulkovo Denis L. Gorshanov, N. A. Shakht, A. A. Kisselev and E. V. Poliakow; 13. Formation of the solar system by instability Evgeny Griv and Michael Gedalin; 14. Behaviour of a two-planetary system on a cosmogonic time-scale Konstantin V. Kholshevnikov and Eduard D. Kuznetsov; 15. Boundaries of the habitable zone: unifying dynamics, astrophysics, and astrobiology Milan M. Cirkovic; 16. Asteroid proper elements: recent computational progress Fernando Roig and Cristian Beaugé; 17. Asteroid family classification from very large catalogues Anne Lemaitre; 18. Non-gravitational perturbations and evolution of the asteroid main belt David Vokrouhlicky, M. Broz and W. F. Bottke, D. Nesvorny and A. Morbidelli; 19. Diffusion in the asteroid belt Harry Varvoglis; 20. Accurate model for the Yarkovsky effect David Capek and David Vokrouhlicky; 21. The

  7. An outline of planetary geoscience. [philosophy

    Science.gov (United States)

    1977-01-01

    A philosophy for planetary geoscience is presented to aid in addressing a number of major scientific questions; answers to these questions should constitute the basic geoscientific knowledge of the solar system. However, any compilation of major questions or basic knowledge in planetary geoscience involves compromises and somewhat arbitrary boundaries that reflect the prevalent level of understanding at the time.

  8. SPEX: The spectropolarimeter for planetary EXploration

    NARCIS (Netherlands)

    Snik, F.; Rietjens, J.H.H.; Harten, G. van; Stam, D.M.; Keller, C.U.; Smit, J.M.; Laan, E.C.; Verlaan, A.L.; Horst, R. ter; Navarro, R.; Wielinga, K.; Moon, S.G.; Voors, R.

    2010-01-01

    SPEX (Spectropolarimeter for Planetary EXploration) is an innovative, compact instrument for spectropolarimetry, and in particular for detecting and characterizing aerosols in planetary atmospheres. With its ∼1-liter volume it is capable of full linear spectropolarimetry, without moving parts. The d

  9. The ExoMars Entry & Descent system: an enabler for European planetary science

    Science.gov (United States)

    Lebleu, D.; Monier, J.; Marchand, B.; Squillaci, J.-R.; Lubrano, G.; Capus, P.; Laurenti, P.; Poncy, J.; Couzin, P.

    2013-09-01

    After HUYGENS and thanks to the ExoMars Entry and Descent System, Europe will confirm the capacity to land on planetary bodies. This presentation reports the development status of ExoMars EDM Entry & Descent system. All development tests are performed, and the subsystems flight models manufacturing are in progress.

  10. On the formation of compact planetary systems via concurrent core accretion and migration

    Science.gov (United States)

    Coleman, Gavin A. L.; Nelson, Richard P.

    2016-04-01

    We present the results of planet formation N-body simulations based on a comprehensive physical model that includes planetary mass growth through mutual embryo collisions and planetesimal/boulder accretion, viscous disc evolution, planetary migration and gas accretion on to planetary cores. The main aim of this study is to determine which set of model parameters leads to the formation of planetary systems that are similar to the compact low-mass multiplanet systems that have been discovered by radial velocity surveys and the Kepler mission. We vary the initial disc mass, solids-to-gas ratio and the sizes of the boulders/planetesimals, and for a restricted volume of the parameter space we find that compact systems containing terrestrial planets, super-Earths and Neptune-like bodies arise as natural outcomes of the simulations. Disc models with low values of the solids-to-gas ratio can only form short-period super-Earths and Neptunes when small planetesimals/boulders provide the main source of accretion, since the mobility of these bodies is required to overcome the local isolation masses for growing embryos. The existence of short-period super-Earths around low-metallicity stars provides strong evidence that small, mobile bodies (planetesimals, boulders or pebbles) played a central role in the formation of the observed planets.

  11. Europa Clipper Mission Concept Preliminary Planetary Protection Approach

    Science.gov (United States)

    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

  12. Cosmic Education: Formation of a Planetary and Cosmic Personality

    Directory of Open Access Journals (Sweden)

    Bazaluk Oleg

    2012-04-01

    Full Text Available The major stages of development of cosmic pedagogy have been researched. Based on the achievements of the modern neurosciences as well as of psychology, cosmology, and philosophy, the authors provide their reasoning for the cosmic education and its outlooks for the educational systems of the world. Through the studies of how important human mind is for the Earth and the cosmos and by researching the evolution of human mind within the structure of the Universe, the authors create a more advanced scientific and philosophic basis for the cosmic education where the subject is a comprehensive process of formation and directed progress of both an individual mind and a conglomerate of minds called the "psychospace". The cosmic education researches the permanent progress of the intelligent matter of the Earth. The purpose of the cosmic education has been determined as formation of a planetary and cosmic personality. According to the authors, a planetary and cosmic personality is a harmony of mind, soul, and body, and such harmony is directed to use the internal creative potential of mind to the benefit of the intelligent matter of the entire Earth and the cosmos. The properties of such a planetary and cosmic personality are being improved continuously; they are a sample (the ideal of the cosmic pedagogy and the image of a human being of the future. Through the usage of the entire potential and art of upbringing and educating, the cosmic pedagogy is called to embody the major properties of the image of a human being of the future in the new generations of minds and to form a planetary and cosmic personality capable of self-actualization to the benefit of the permanent progress of the intelligent matter.

  13. Lunar and Planetary Science XXXVI, Part 13

    Science.gov (United States)

    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

  14. Natural Shock Sintering of Unconsolidated Planetary Materials

    Science.gov (United States)

    Spray, J. G.

    2006-12-01

    On Earth, the transformation of unconsolidated sediment (e.g., sand) to rock (sandstone) occurs via the process of lithification. Lithification typically occurs via burial within the upper crust at less than 150 degrees celsius, at depths of less than 5 km in the presence of liquid H2O. Liquid H2O is often important in the process of lithification because it is the transporting medium for dissolved and suspended ions and mineral species, which eventually precipitate as a cement that binds the unconsolidated grains. Lithification also applies to sedimentary deposits formed by precipitation of minerals from aqueous solutions at surface, or near- surface, conditions (e.g., to generate sulfate or carbonate-rich evaporites). However, for many planetary bodies in our solar system, there are no large sources of liquid H2O to facilitate this type of lithification process. Despite the absence of water on such bodies, the development of consolidated fragmental material is commonplace and it probably dominates the surface materials of Mercury, the Moon, Mars and many asteroids. This material, typically in the form of breccias, is a relatively coherent rock, yet the nature of the "glue" that binds the fragments is not well understood. Clearly, other processes are responsible for the lithification that we take for granted in many of the sedimentary rocks developed on our wet planet. This work explores these processes. For certain planetary bodies unconsolidated material may be bound by ices, such that it possesses rock-like properties in terms in strength and behaviour. In the absence of H2O, unconsolidated semi-molten material can be lithified by welding and compaction (e.g., certain pyroclastic discharges that fall and accumulate to form ignimbrites). This requires the production of hot volcanogenic or impact ejecta. In this work we explore the nature of the binding medium in different types of lunar breccia collected during the Apollo15, 16 and 17 missions, in meteorites of

  15. Observability during planetary approach navigation

    Science.gov (United States)

    Bishop, Robert H.; Burkhart, P. Daniel; Thurman, Sam W.

    1993-01-01

    The objective of the research is to develop an analytic technique to predict the relative navigation capability of different Earth-based radio navigation measurements. In particular, the problem is to determine the relative ability of geocentric range and Doppler measurements to detect the effects of the target planet gravitational attraction on the spacecraft during the planetary approach and near-encounter mission phases. A complete solution to the two-dimensional problem has been developed. Relatively simple analytic formulas are obtained for range and Doppler measurements which describe the observability content of the measurement data along the approach trajectories. An observability measure is defined which is based on the observability matrix for nonlinear systems. The results show good agreement between the analytic observability analysis and the computational batch processing method.

  16. Formation around planetary displaced orbit

    Institute of Scientific and Technical Information of China (English)

    GONG Sheng-ping; LI Jun-feng; BAOYIN He-xi

    2007-01-01

    The paper investigates the relative motion around the planetary displaced orbit. Several kinds of displaced orbits for geocentric and martian cases were discussed. First, the relative motion was linearized around the displaced orbits. Then, two seminatural control laws were investigated for each kind of orbit and the stable regions were obtained for each case. One of the two control laws is the passive control law that is very attractive for engineering practice. However, the two control laws are not very suitable for the Martian mission. Another special semi-natural control law is designed based on the requirement of the Martian mission. The results show that large stable regions exist for the control law.

  17. Heat transfer and planetary evolution

    Science.gov (United States)

    Tozer, D. C.

    1985-06-01

    The object of this account is to show how much one can interprete and predict about the present state of material forming planet size objects, despite the fact we do not and could never have the kind of exact or prior knowledge of initial conditions and in situ material behaviour that would make a formal mathematical analysis of the dynamical problems of planetary evolution an efficient or meaningful exercise The interest and usefulness of results obtained within these limitations stem from the highly non linear nature of planetary scale heat transfer problems when posed in any physically plausible form. The non linearity arising from a strongly temperature dependent rheology assumed for in situ planetary material is particularly valuable in deriving results insensitive to such uncertainties. Qualitatively, the thermal evolution of a planet is quite unlike that given by heat conduction calculation below a very superficial layer, and much unnecessary argument and confusion results from a persistent failure to recognise that fact. At depths that are no greater on average than a few tens of kilometres in the case of Earth, the temperature distribution is determined by a convective flow regime inaccessble to the laboratory experimenter and to the numerical methods regularly employed to study convective movement. A central and guiding quantitative result is the creation in homogeneous planet size objects having surface temperatures less than about half the absolute melting temperature of their material, of internal states with horizontally a veraged viscosity values ˜1021 poise. This happens in times short compared with the present Solar System age. The significance of this result for an understanding of such processes and features as isostasy, continental drift, a minimum in seismic S wave velocity in Earth's upper mantle, a uniformity of mantle viscosity values, the survival of liquid planetary cores and the differentiation of terrestrial planet material is examined

  18. Planetary Data System (PDS) Strategic Roadmap

    Science.gov (United States)

    Law, Emily; McNutt, Ralph; Crichton, Daniel J.; Morgan, Tom

    2016-07-01

    The Planetary Data System (PDS) archives and distributes scientific data from NASA planetary missions, astronomical observations, and laboratory measurements. NASA's Science Mission Directorate (SMD) sponsors the PDS. Its purpose is to ensure the long-term usability of NASA data and to stimulate advanced research. The Planetary Science Division (PSD) within the SMD at NASA Headquarters has directed the PDS to set up a Roadmap team to formulate a PDS Roadmap for the period 2017-2026. The purpose of this activity is to provide a forecast of both the rapidly changing Information Technology (IT) environment and the changing expectations of the planetary science communities with respect to Planetary Data archives including, specifically, increasing assessability to all planetary data. The Roadmap team will also identify potential actions that could increase interoperability with other archive and curation elements within NASA and with the archives of other National Space Agencies. The Roadmap team will assess the current state of the PDS and report their findings to the PSD Director by April 15, 2017. This presentation will give an update of this roadmap activity and serve as an opportunity to engage the planetary community at large to provide input to the Roadmap.

  19. Ground tests with active neutron instrumentation for the planetary science missions

    International Nuclear Information System (INIS)

    We present results of experimental work performed with a spare flight model of the DAN/MSL instrument in a newly built ground test facility at the Joint Institute for Nuclear Research. This instrument was selected for the tests as a flight prototype of an active neutron spectrometer applicable for future landed missions to various solid solar system bodies. In our experiment we have fabricated simplified samples of planetary material and tested the capability of neutron activation methods to detect thin layers of water/water ice lying on top of planetary dry regolith or buried within a dry regolith at different depths

  20. Cold aqueous planetary geochemistry with FREZCHEM from modeling to the search for life at the limits

    CERN Document Server

    Marion, Giles M

    2007-01-01

    This book explicitly investigates issues of astrobiological relevance in the context of cold aqueous planetary geochemistry. At the core of the technical chapters is the FREZCHEM model, initially developed over many years by one of the authors to quantify aqueous electrolyte properties and chemical thermodynamics at subzero temperatures. FREZCHEM, of general relevance to biogeochemists and geochemical modelers, cold planetary scientists, physicochemists and chemical engineers, is subsequently applied to the exploration of biogeochemical applications to solar systems bodies in general, and to speculations about the limits for life in cold environments in particular.

  1. Planetary climates (princeton primers in climate)

    CERN Document Server

    Ingersoll, Andrew

    2013-01-01

    This concise, sophisticated introduction to planetary climates explains the global physical and chemical processes that determine climate on any planet or major planetary satellite--from Mercury to Neptune and even large moons such as Saturn's Titan. Although the climates of other worlds are extremely diverse, the chemical and physical processes that shape their dynamics are the same. As this book makes clear, the better we can understand how various planetary climates formed and evolved, the better we can understand Earth's climate history and future.

  2. The Planetary Data System--preparing for a New Decade

    Science.gov (United States)

    Morgan, Thomas H.; Knopf, William P.; Grayzeck, Edwin J.

    2015-11-01

    In order to improve NASA’s ability to serve the Planetary Science Community, the Planetary Data System (PDS) has been transformed. NASA has used the highly successful virtual institute model (e.g., for NASA’s Astrobiology Program) to re-compete the Science Nodes within the PDS Structure. The new institute structure will facilitate our efforts within the PDS to improve both archive searchability and product discoverability. We will continue the adaption of the new PDS4 Standard, and enhance our ability to work with other archive/curation activities within NASA and with the community of space faring nations (through the IPDA). PDS science nodes will continue to work with NASA missions from the initial Announcement of Opportunity through the end of mission to define, organize, and document the data. This process includes peer-review of data sets by members of the science community to ensure that the data sets are scientifically useful, effectively organized, and well documented.The Science nodes were selected through a Cooperative Agreement Notice (NNH15ZDA006C) which specifically allowed the community to propose specific archive concepts. The selected nodes are: Cartography and Imaging Sciences, Rings-Moon Systems, Planetary Geosciences, Planetary Plasma Interactions, Atmospheres, and Small Bodies. Other elements of the PDS include an Engineering Node, the Navigation and Ancillary Information Facility, and a small project office.The prime role of the PDS is unchanged. We archive and distribute scientific data from NASA planetary missions, astronomical observations, and laboratory measurements. NASA’s Science Mission Directorate sponsors the PDS. Its purpose is to ensure the long-term usability of NASA data and to stimulate advanced research.In this presentation we discuss recent changes in the PDS, and our future activities to build on the new Institute. Near term efforts include developing a PDS Roadmap for the next decade lead by PDS Chief Scientist, Dr

  3. Planetary deep interiors, geodesy, and habitability

    Science.gov (United States)

    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

  4. Planetary science: Cometary dust under the microscope

    Science.gov (United States)

    Kolokolova, Ludmilla

    2016-09-01

    The Rosetta spacecraft made history by successfully orbiting a comet. Data from the craft now reveal the structure of the comet's dust particles, shedding light on the processes that form planetary systems. See Letter p.73

  5. Annual review of earth and planetary sciences

    International Nuclear Information System (INIS)

    This book covers: shock modifications and chemistry and planetary geologic processes; nuclear winter: physics and physical mechanisms; fractals in rock physics; experimental determination of bed-form stability; and other topics

  6. Low-energy Planetary Excavator (LPE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop an innovative Low-energy Planetary Excavator (LPE) to excavate in situ regolith, ice-regolith mixes, and a variety of other geologic...

  7. Low-energy Planetary Excavator (LPE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC is developing an innovative Low-energy Planetary Excavator (LPE) to excavate in situ regolith, ice-regolith mixes, and a variety of other geologic materials...

  8. Sensor Array Analyzer for Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future planetary exploration missions such as those planned by NASA and other space agencies over the next few decades require advanced chemical and biological...

  9. Planetary Geochemistry Techniques: Probing In-Situ with Neutron and Gamma Rays (PING) Instrument

    Science.gov (United States)

    Parsons, A.; Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S.; Lin, L.; McClanahan, T.; Nankung, M.; Nowicki, S.; Schweitzer, J.; Starr, R.; Trombka, J.

    2011-01-01

    The Probing In situ with Neutrons and Gamma rays (PING) instrument is a promising planetary science application of the active neutron-gamma ray technology so successfully used in oil field well logging and mineral exploration on Earth. The objective of our technology development program at NASA Goddard Space Flight Center's (NASA/GSFC) Astrochemistry Laboratory is to extend the application of neutron interrogation techniques to landed in situ planetary composition measurements by using a 14 MeV Pulsed Neutron Generator (PNG) combined with neutron and gamma ray detectors, to probe the surface and subsurface of planetary bodies without the need to drill. We are thus working to bring the PING instrument to the point where it can be flown on a variety of surface lander or rover missions to the Moon, Mars, Venus, asteroids, comets and the satellites of the outer planets.

  10. Period ratios in multi-planetary systems discovered by Kepler are consistent with planet migration

    CERN Document Server

    Rein, Hanno

    2012-01-01

    The Kepler planet candidates are an interesting testbed for planet formation scenarios. We present results from N-body simulations of multi-planetary systems that resemble those observed by Kepler. We add both smooth (Type I/II) and stochastic migration forces. The observed period ratio distribution is inconsistent with either of those two scenarios on its own. However, applying both stochastic and smooth migration forces to the planets simultaneously results in a period ratio distribution that is similar to the observed one. This is a natural scenario if planets form in a turbulent proto-planetary disk where these forces are always present. We show how the observed period ratio and eccentricity distribution can constrain the relative strength of these forces, a parameter which has been notoriously hard to predict for decades. We make the source code of our simulations and the initial conditions freely available to enable the community to expand this study and include effect other than planetary migration.

  11. Radar scattering by planetary surfaces modeled with laboratory-characterized particles

    Science.gov (United States)

    Virkki, A.; Muinonen, K.

    2016-05-01

    We model radar scattering by planetary surfaces using a ray-optics algorithm that includes Fresnelian reflection and refraction, diffuse scattering, and coherent backscattering. We enhance the realism of the ray-optics algorithm by using scattering particles that are geometrically representative of the surfaces and interiors of planetary bodies. The shapes as well as the dielectric properties of the scattering particles have been characterized in laboratory. The results demonstrate the effects of various physical parameters on radar scattering with an emphasis on asteroids. We present the effects of number density, size distribution, and dielectric and geometric properties of scattering particles on the radar reflectivity and circular-polarization ratio of planetary surfaces. We also briefly discuss applications to the Galilean Moon Europa and comets.

  12. Fluid dynamics of planetary ices

    CERN Document Server

    Greve, Ralf

    2009-01-01

    The role of water ice in the solar system is reviewed from a fluid-dynamical point of view. On Earth and Mars, water ice forms ice sheets, ice caps and glaciers at the surface, which show glacial flow under their own weight. By contrast, water ice is a major constituent of the bulk volume of the icy satellites in the outer solar system, and ice flow can occur as thermal convection. The rheology of polycrystalline aggregates of ordinary, hexagonal ice Ih is described by a power law, different forms of which are discussed. The temperature dependence of the ice viscosity follows an Arrhenius law. Therefore, the flow of ice in a planetary environment constitutes a thermo-mechanically coupled problem; its model equations are obtained by inserting the flow law and the thermodynamic material equations in the balance laws of mass, momentum and energy. As an example of gravity-driven flow, the polar caps of Mars are discussed. For the north-polar cap, large-scale flow velocities of the order of 0.1...1 mm/a are likely...

  13. Extrasolar Planetary Imaging Coronagraph (EPIC)

    Science.gov (United States)

    Clampin, Mark

    2009-01-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a proposed NASA Exoplanet Probe mission to image and characterize extrasolar giant planets. EPIC will provide insights into the physical nature and architecture of a variety of planets in other solar systems. Initially, it will detect and characterize the atmospheres of planets identified by radial velocity surveys, determine orbital inclinations and masses and characterize the atmospheres around A and F type stars which cannot be found with RV techniques. It will also observe the inner spatial structure of exozodiacal disks. EPIC has a heliocentric Earth trailing drift-away orbit, with a 5 year mission lifetime. The robust mission design is simple and flexible ensuring mission success while minimizing cost and risk. The science payload consists of a heritage optical telescope assembly (OTA), and visible nulling coronagraph (VNC) instrument. The instrument achieves a contrast ratio of 10^9 over a 5 arcsecond field-of-view with an unprecedented inner working angle of 0.13 arcseconds over the spectral range of 440-880 nm. The telescope is a 1.65 meter off-axis Cassegrain with an OTA wavefront error of lambda/9, which when coupled to the VNC greatly reduces the requirements on the large scale optics.

  14. Zinc abundances of planetary nebulae

    CERN Document Server

    Smith, Christina L; Dinerstein, Harriet L

    2014-01-01

    Zinc is a useful surrogate element for measuring Fe/H as, unlike iron, it is not depleted in the gas phase media. Zn/H and O/Zn ratios have been derived using the [Zn IV] emission line at 3.625um for a sample of nine Galactic planetary nebulae, seven of which are based upon new observations using the VLT. Based on photoionization models, O/O++ is the most reliable ionisation correction factor for zinc that can readily be determined from optical emission lines, with an estimated accuracy of 10% or better for all targets in our sample. The majority of the sample is found to be sub-solar in [Zn/H]. [O/Zn] in half of the sample is found to be consistent with Solar within uncertainties, whereas the remaining half are enhanced in [O/Zn]. [Zn/H] and [O/Zn] as functions of Galactocentric distance have been investigated and there is little evidence to support a trend in either case.

  15. Unveiling shocks in planetary nebulae

    CERN Document Server

    Guerrero, M A; Medina, J J; Luridiana, V; Miranda, L F; Riera, A; Velázquez, P F

    2013-01-01

    The propagation of a shock wave into a medium is expected to heat the material beyond the shock, producing noticeable effects in intensity line ratios such as [O III]/Halpha. To investigate the occurrence of shocks in planetary nebulae (PNe), we have used all narrowband [O III] and Halpha images of PNe available in the HST archive to build their [O III]/Halpha ratio maps and to search for regions where this ratio is enhanced. Regions with enhanced [O III]/Halpha emission ratio can be ascribed to two different types of morphological structures: bow-shock structures produced by fast collimated outflows and thin skins enveloping expanding nebular shells. Both collimated outflows and expanding shells are therefore confirmed to generate shocks in PNe. We also find regions with depressed values of the [O III]/Halpha ratio which are found mostly around density bounded PNe, where the local contribution of [N II] emission into the F656N Halpha filter cannot be neglected.

  16. Cosmological aspects of planetary habitability

    CERN Document Server

    Shchekinov, Yu A; Murthy, J

    2014-01-01

    The habitable zone (HZ) is defined as the region around a star where a planet can support liquid water on its surface, which, together with an oxygen atmosphere, is presumed to be necessary (and sufficient) to develop and sustain life on the planet. Currently, about twenty potentially habitable planets are listed. The most intriguing question driving all these studies is whether planets within habitable zones host extraterrestrial life. It is implicitly assumed that a planet in the habitable zone bears biota. However along with the two usual indicators of habitability, an oxygen atmosphere and liquid water on the surface, an additional one -- the age --- has to be taken into account when the question of the existence of life (or even a simple biota) on a planet is addressed. The importance of planetary age for the existence of life as we know it follows from the fact that the primary process, the photosynthesis, is endothermic with an activation energy higher than temperatures in habitable zones. Therefore on...

  17. Post-main-sequence planetary system evolution.

    Science.gov (United States)

    Veras, Dimitri

    2016-02-01

    The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the interpretation and modelling of currently known systems and upcoming discoveries. PMID:26998326

  18. Preface: New challenges for planetary protection

    Science.gov (United States)

    Kminek, Gerhard

    2016-05-01

    Planetary protection as a discipline goes back to the advent of the space age and the formation of the Committee on Space Research (COSPAR). Planetary protection constraints are in place to ensure that scientific investigations related to the search for extraterrestrial life are not compromised and that the Earth is protected from the potential hazard posed by extraterrestrial matter carried by a spacecraft returning from an interplanetary mission.

  19. NAVIGATION, GUIDANCE AND CONTROL FOR PLANETARY LANDING

    OpenAIRE

    Perez Montenegro, Carlos Norberto

    2014-01-01

    This dissertation aims to develop algorithms of guidance and control for propulsive terminal phase planetary landing, including a piloting strategy. The algorithms developed here are based on the Embedded Model Control (EMC) principles. Currently, the planetary entry descent and landing are important issues, landing on Mars and Moon has been scientifically rewarding; successful landed robotic systems on the surface of Mars have been achieved. Projects as Mars Science Laboratory MSL inter alia...

  20. Post-main-sequence planetary system evolution

    CERN Document Server

    Veras, Dimitri

    2016-01-01

    The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the interpretation and modelling of currently known systems and upcoming discoveries.

  1. Planetary boundaries: Governing emerging risks and opportunities

    OpenAIRE

    Galaz, V.; de Zeeuw, Aart; SHIROYAMA Hideaki; Tripley, Debbie

    2016-01-01

    The climate, ecosystems and species, ozone layer, acidity of the oceans, the flow of energy and elements through nature, landscape change, freshwater systems, aerosols, and toxins—these constitute the planetary boundaries within which humanity must find a safe way to live and prosper. These are thresholds that, if we cross them, we run the risk of rapid, non-linear, and irreversible changes to the environment, with severe consequences for human wellbeing. The concept of planetary boundaries, ...

  2. Automatic Feature Extraction from Planetary Images

    Science.gov (United States)

    Troglio, Giulia; Le Moigne, Jacqueline; Benediktsson, Jon A.; Moser, Gabriele; Serpico, Sebastiano B.

    2010-01-01

    With the launch of several planetary missions in the last decade, a large amount of planetary images has already been acquired and much more will be available for analysis in the coming years. The image data need to be analyzed, preferably by automatic processing techniques because of the huge amount of data. Although many automatic feature extraction methods have been proposed and utilized for Earth remote sensing images, these methods are not always applicable to planetary data that often present low contrast and uneven illumination characteristics. Different methods have already been presented for crater extraction from planetary images, but the detection of other types of planetary features has not been addressed yet. Here, we propose a new unsupervised method for the extraction of different features from the surface of the analyzed planet, based on the combination of several image processing techniques, including a watershed segmentation and the generalized Hough Transform. The method has many applications, among which image registration and can be applied to arbitrary planetary images.

  3. Europlanet - Joining the European Planetary Research Information Service

    Science.gov (United States)

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

    2009-04-01

    to data to be integrated into the VO features of IDIS? Any combination and many more alternatives are possible. 3. Contact the staff of the selected node(s) to go through the details 4. The node's expert team will evaluate the information to ensure that it is compliant with the minimum requirements for Europlanet information providers like correct address, related field of competence, quality of data if any etc. 5. The new resource meta data (addresses, contents etc) will be added to the IDIS system including update of the search facilities 6. If data are offered for on-line access, the IDIS team will provide tools to generate a network-compatible generic interface. This one-time effort will make it possible to search the new data sets and combine them with related in-formation from other sources. Benefits for the information provider: - wide advertisement for the own resources and capabilities with increase in scientific references to the own activities and publications - new co-operation possibilities with so far unknown teams. Team exchange might be financially supported by other segments of the Europlanet RI - strong arguments for new funding applications and many more aspects List of contact web-sites: Technical node for support and management aspects: http://www.europlanet-idis.fi/ Planetary Surfaces and Interiors node: http://europlanet.dlr.de/ Planetary Plasma node: http://europlanet-plasmanode.oeaw.ac.at/ Planetary Atmospheres node: http://idis.ipsl.jussieu.fr/ Virtual Observatory Paris Data Centre: http://vo.obspm.fr/ Small Bodies and Dust node: http://www.ifsi-roma.inaf.it/europlanet/

  4. Planetary Protection Alternate Protocol Certification

    Science.gov (United States)

    Baker, Amy; Barengoltz, Jack; Tisdale, David

    The talk presents a standardized approach for new method certification or alterative testing protocol (ATP) certification against the existing U.S. Planetary Protection Standards. In consideration of new method certification there are two phases of activities that are relevant to the certification process. The first is sample acquisition which typically incorporates swab or wipes sampling on relevant hardware, associated facilities and ground support equipment. The sampling methods introduce considerations of field sampling efficiency as it relates to spore distribution on the spacecraft, spacecraft material influences on the ability of the swab or wipe to remove spores from the hardware, the types of swabs and wipes used (polyester, cotton, macrofoam), and human sampling influences. The second portion of a new protocol certification looks specifically at the lab work-up or analysis of the samples provided to the laboratory. Variables in this process include selection of appropriate biomarkers, extraction efficiencies (removal of spores or constituents of interest from the sampling device), and a method's ability to accurately determine the number of spores present in the sample with a statistically valid level of confidence as described by parameters such as precision, accuracy, robustness, specificity and sensitivity. Considerations for alternative testing protocols such as those which utilize bioburden reduction techniques include selection of appropriate biomarkers for testing, test materials and a defined statistical approach that provides sufficient scientific data to support the modification of an existing NASA specification or the generation of a new NASA specification. Synergies between the U.S. and European Space Agency approaches will also be discussed.

  5. The frequency and chemical composition of rocky planetary debris around young white dwarfs: Plugging the last gaps

    Science.gov (United States)

    Gaensicke, Boris

    2014-10-01

    Many planetary systems will survive the post main-sequence evolution of their host stars into white dwarfs (WDs). In the solar system, Mars, the asteroid belt, and the outer planets will eventually orbit the WD remnant of the Sun, and many WDs are known to have remnants of planetary systems. Historically, planetary debris was detected in ~20% of WDs with cooling ages >0.5Gyr from Ca K detections. However, the Ca II ionisation balance makes the ground-based detection of planetary debris at younger, hotter WDs impossible.We have carried out a very successful Cycle 18/19 COS snapshot survey of 100 WDs with cooling ages of 20-200Myr, and detect metal pollution in up to 50% of all targets via the strong Si resonance lines. This survey also showed that terrestrial material is common around A-stars, that rocky exo-planetary bodies display a similar variety in abundances as the meteorites in our solar system, and that water-rich Ceres-like asteroids still exist in evolved planetary systems. We propose to close the last gaps in the statistics of evolved planetary systems: an extension of our snapshot survey to cooling ages of 5-25Myr and 100-300Myr. Our orbital integrations suggest that mass-loss during the AGB phase can stirr up instabilities leading to planet-planet collisions, which should be most frequent during the first 10Myr, and the proposed observations will unambiguously test these predictions. In addition, the extended sample will improve the statistics on the formation of planetary systems as a function of host star mass, and build up a deeper insight into the abundances of rocky exo-planetary material that will guide models of terrestrial planet formation

  6. On the formation of compact planetary systems via concurrent core accretion and migration

    CERN Document Server

    Coleman, Gavin A L

    2016-01-01

    We present the results of planet formation N-body simulations based on a comprehensive physical model that includes planetary mass growth through mutual embryo collisions and planetesimal/boulder accretion, viscous disc evolution, planetary migration and gas accretion onto planetary cores. The main aim of this study is to determine which set of model parameters leads to the formation of planetary systems that are similar to the compact low mass multi-planet systems that have been discovered by radial velocity surveys and the Kepler mission. We vary the initial disc mass, solids-to-gas ratio and the sizes of the boulders/planetesimals, and for a restricted volume of the parameter space we find that compact systems containing terrestrial planets, super-Earths and Neptune-like bodies arise as natural outcomes of the simulations. Disc models with low values of the solids-to-gas ratio can only form short-period super-Earths and Neptunes when small planetesimals/boulders provide the main source of accretion, since ...

  7. Model of the accumulation process in the formation of planetary systems. I. Numerical experiments

    International Nuclear Information System (INIS)

    This work considers the evolution of a plane protoplanetary nebula consisting of a large number of bodies (protoplanets), which interact gravitationally, combine on contact, and move in the field of a massive central body (the sun or a planet). It is assumed that the gravitational interaction between bodies occurs only during their binary close approach. It is also assumed that the bodies move in Keplerian orbits between close approaches and that the orbits of all the bodies are circular at the initial time of evolution of the cloud. The so-called limit model of the accumulation process, in which each close approach of bodies is terminated by their combining, is considered. It is shown that in the course of evolution of such a model there appear annular zones of material condensation whose subsequent development leads to the formation of planets with predominantly direct rotation about their axes. The principal numerical results are obtained by computer simulation of the planetary accumulation process

  8. MExLab Planetary Geoportal: 3D-access to planetary images and results of spatial data analysis

    Science.gov (United States)

    Karachevtseva, I.; Garov, A.

    2015-10-01

    MExLab Planetary Geoportal was developed as Geodesy and Cartography Node which provide access to results of study of celestial bodies such as DEM and orthoimages, as well as basemaps, crater catalogues and derivative products: slope, roughness, crater density (http://cartsrv.mexlab.ru/geoportal). The main feature of designed Geoportal is the ability of spatial queries and access to the contents selecting from the list of available data set (Phobos, Mercury, Moon, including Lunokhod's archive data). Prior version of Geoportal has been developed using Flash technology. Now we are developing new version which will use 3D-API (OpenGL, WebGL) based on shaders not only for standard 3D-functionality, but for 2D-mapping as well. Users can obtain quantitative and qualitative characteristics of the objects in graphical, tabular and 3D-forms. It will bring the advantages of unification of code and speed of processing and provide a number of functional advantages based on GIS-tools such as: - possibility of dynamic raster transform for needed map projection; - effective implementation of the co-registration of planetary images by combining spatial data geometries; - presentation in 3D-form different types of data, including planetary atmospheric measurements, subsurface radar data, ect. The system will be created with a new software architecture, which has a potential for development and flexibility in reconfiguration based on cross platform solution: - an application for the three types of platforms: desktop (Windows, Linux, OSX), web platform (any HTML5 browser), and mobile application (Android, iOS); - a single codebase shared between platforms (using cross compilation for Web); - a new telecommunication solution to connect between modules and external system like PROVIDE WebGIS (http://www.provide-space.eu/progis/). The research leading to these result was partly supported by the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n

  9. Chaotic Diffusion in the Gliese-876 Planetary System

    Science.gov (United States)

    Martí, J. G.; Cincotta, P. M.; Beaugé, C.

    2016-05-01

    Chaotic diffusion is supposed to be responsible for orbital instabilities in planetary systems after the dissipation of the protoplanetary disk, and a natural consequence of irregular motion. In this paper we show that resonant multi-planetary systems, despite being highly chaotic, not necessarily exhibit significant diffusion in phase space, and may still survive virtually unchanged over timescales comparable to their age.Using the GJ-876 system as an example, we analyze the chaotic diffusion of the outermost (and less massive) planet. We construct a set of stability maps in the surrounding regions of the Laplace resonance. We numerically integrate ensembles of close initial conditions, compute Poincaré maps and estimate the chaotic diffusion present in this system. Our results show that, the Laplace resonance contains two different regions: an inner domain characterized by low chaoticity and slow diffusion, and an outer one displaying larger values of dynamical indicators. In the outer resonant domain, the stochastic borders of the Laplace resonance seem to prevent the complete destruction of the system. We characterize the diffusion for small ensembles along the parameters of the outermost planet. Finally, we perform a stability analysis of the inherent chaotic, albeit stable Laplace resonance, by linking the behavior of the resonant variables of the configurations to the different sub-structures inside the three-body resonance.

  10. X-ray Imaging Spectroscopy for Planetary Science

    Science.gov (United States)

    Kraft, Ralph P.; Kenter, A.; Murray, S.; Elvis, M.; Branduardi-Raymont, G.; Garcia, M.; Forman, W.; Geary, J.; McCoy, T.; Smith, R.

    2012-10-01

    We are developing monolithic backside illuminated CMOS detectors as soft X-ray imaging spectrometers for high energy astrophysics missions. These devices represent a significant advance over CCD technology and have unique properties that would make them ideal sensors for various planetary mission concepts. The benefits of CMOS include higher levels of integration which provide maximum pixel gain and therefore very low noise, very fast parallel output signal chains for high frame rates. CMOS imaging detectors have zero or one charge transfer so that they can withstand many orders of magnitude more radiation than conventional CCDs before degradation. The capability of high read rates provides dynamic range and temporal resolution. Additionally, the rapid read rates minimize shot noise from thermal dark current and optical light. CMOS detectors can therefore run at warmer temperatures and with ultra-thin optical blocking filters. Thin OBFs provide near unity quantum efficiency below 1 keV, thus maximizing response at the C and O lines. Possible mission concepts for these sensors include X-ray fluorescence studies of rocky bodies, and investigation of the magnetospheres of the gas giants and their moons. In this presentation, we discuss the current state of our technology development and outline its scientific potential for planetary physics with particular emphasis on studies of the Jovian magnetosphere. We contrast the capabilities of our instrument with that which has been achieved by the current generation of Earth-orbiting X-ray observatories.

  11. TRANSIENT CHAOS AND FRACTAL STRUCTURES IN PLANETARY FEEDING ZONES

    Energy Technology Data Exchange (ETDEWEB)

    Kovács, T. [Also at University of Applied Sciences, Nagy Lajos kir. útja 1-9, H-1148 Budapest, Hungary. (Hungary); Regály, Zs. [Konkoly Observatory of the Hungarian Academy of Sciences, P.O. Box 67, H-1525 Budapest (Hungary)

    2015-01-01

    The circular restricted three-body problem is investigated in the context of accretion and scattering processes. In our model, a large number of identical non-interacting mass-less planetesimals are considered in the planar case orbiting a star-planet system. This description allows us to investigate the gravitational scattering and possible capture of the particles by the forming planetary embryo in a dynamical systems approach. Although the problem serves a large variety of complex motions, the results can be easily interpreted because of the low dimensionality of the phase space. We show that initial conditions define isolated regions of the disk, where planetesimals accrete or escape, which have, in fact, a fractal structure. The fractal geometry of these ''basins'' implies that the dynamics is very complex. Based on the calculated escape rates and escape times, it is also demonstrated that the planetary accretion rate is exponential for short times and follows a power law for longer integration. A new numerical calculation of the maximum mass that a planet can reach (described by the expression of the isolation mass) is also derived.

  12. A Lagrangian Integrator for Planetary Accretion and Dynamics (LIPAD)

    CERN Document Server

    Levison, Harold F; Thommes, Edward

    2012-01-01

    We presented the first particle based, Lagrangian code that can follow the collisional/accretional/dynamical evolution of a large number of km-sized planetesimals through the entire growth process to become planets. We refer to it as the 'Lagrangian Integrator for Planetary Accretion and Dynamics' or LIPAD. LIPAD is built on top of SyMBA, which is a symplectic $N$-body integrator. In order to handle the very large number of planetesimals required by planet formation simulations, we introduce the concept of a `tracer' particle. Each tracer is intended to represent a large number of disk particles on roughly the same orbit and size as one another, and is characterized by three numbers: the physical radius, the bulk density, and the total mass of the disk particles represented by the tracer. We developed statistical algorithms that follow the dynamical and collisional evolution of the tracers due to the presence of one another. The tracers mainly dynamically interact with the larger objects (`planetary embryos')...

  13. Planetary Protection Bioburden Analysis Program

    Science.gov (United States)

    Beaudet, Robert A.

    2013-01-01

    is programmed in Visual Basic for Applications for installation as a simple add-in for Microsoft Excel. The user is directed to a graphical user interface (GUI) that requires user inputs and provides solutions directly in Microsoft Excel workbooks. This work was done by Shannon Ryan of the USRA Lunar and Planetary Institute for Johnson Space Center. Further information is contained in a TSP (see page 1). MSC- 24582-1 Micrometeoroid and Orbital Debris (MMOD) Shield Ballistic Limit Analysis Program Lyndon B. Johnson Space Center, Houston, Texas Commercially, because it is so generic, Enigma can be used for almost any project that requires engineering visualization, model building, or animation. Models in Enigma can be exported to many other formats for use in other applications as well. Educationally, Enigma is being used to allow university students to visualize robotic algorithms in a simulation mode before using them with actual hardware. This work was done by David Shores and Sharon P. Goza of Johnson Space Center; Cheyenne McKeegan, Rick Easley, Janet Way, and Shonn Everett of MEI Technologies; Mark Manning of PTI; and Mark Guerra, Ray Kraesig, and William Leu of Tietronix Software, Inc. For further information, contact the JSC Innovation Partnerships Office at (281) 483-3809. MSC-24211-1 Spitzer Telemetry Processing System NASA's Jet Propulsion Laboratory, Pasadena, California The Spitzer Telemetry Processing System (SirtfTlmProc) was designed to address objectives of JPL's Multi-mission Image Processing Lab (MIPL) in processing spacecraft telemetry and distributing the resulting data to the science community. To minimize costs and maximize operability, the software design focused on automated error recovery, performance, and information management. The system processes telemetry from the Spitzer spacecraft and delivers Level 0 products to the Spitzer Science Center. SirtfTlmProc is a unique system with automated error notification and recovery, with a real

  14. Access to the Online Planetary Research Literature

    Science.gov (United States)

    Henneken, E. A.; Accomazzi, A.; Kurtz, M. J.; Grant, C. S.; Thompson, D.; Di Milia, G.; Bohlen, E.; Murray, S. S.

    2009-12-01

    The SAO/NASA Astrophysics Data System (ADS) provides various free services for finding, accessing, and managing bibliographic data, including a basic search form, the myADS notification service, and private library capabilities (a useful tool for building bibliographies), plus access to scanned pages of published articles. The ADS also provides powerful search capabilities, allowing users to find e.g. the most instructive or most important articles on a given subject . For the Planetary Sciences, the citation statistics of the ADS have improved considerably with the inclusion of the references from Elsevier journals, including Icarus, Planetary and Space Science, and Earth and Planetary Science Letters. We currently have about 78 journals convering the planetary and space sciences (Advances in Space Research, Icarus, Solar Physics, Astrophusics and Space Science, JGRE, Meteoritics, to name a few). Currently, this set of journals represents about 180,000 articles and 1.1 million references. Penetration into the Solar Physics, Planetary Sciences and Geophysics community has increased significantly. During the period 2004-2008, user access to JGR and Icarus increased by a factor of 4.4, while e.g. access to the Astrophysical Journal "only" increased by a factor of 1.8.

  15. Planetary life: why and how?

    Science.gov (United States)

    Pratt, Andy; Kerr, William

    2012-07-01

    Understanding life in an astrobiological context requires that we understand why and how life emerged on earth. We report on the elaboration and preliminary testing of our recent model for the origin of life (Pratt, 2011). This model identifies key components, including availability of chemicals and geochemical energy sources, required for the emergence of planetary life. The model is based on the theory (Russell and Kanik, 2010) that life emerged as a mechanism for the dissipation of the intrinsic geochemical energy gradient of the planet. It proposes that life is founded on an ongoing chemical energy flux that can be harnessed more efficiently by autocatalytic networks of reactions than by direct chemical processes. Feedback and selection mechanisms are required to foster the apparently irreducible complexity found in cells. We posit that selective solubilisation in a hydrothermal flow system was a key mechanism that underpinned the emergence of life. Amongst other things, earthly cells are dependent on a combination of organic molecules, iron (for electron-transfer and catalysis) and phosphate (e.g. for digital information). Soluble aqueous systems that include all these components are constrained by precipitation chemistry (de Zwart et al., 2004). We propose that in situ abiological carbon fixation produced organic molecules that, in turn, led to more active carbon fixation catalysts and hence more efficient reduction of carbon oxides. By encapsulating free iron ions, these organic molecules also facilitated the solubilisation of phosphate species which thereby became integrated within this expanding autocatalytic network. We have evaluated the competitive solubility of phosphate species in the presence of iron and organic moieties to test this theory and provide evidence that this could act as positive feedback loop for a form of prebiological evolution that underpinned the emergence of complex cells. References, Pratt, A. J. (2011) Prebiological Evolution and

  16. Planetary X-ray studies: past, present and future

    Science.gov (United States)

    Branduardi-Raymont, Graziella

    2016-07-01

    Our solar system is a fascinating physics laboratory and X-ray observations are now firmly established as a powerful diagnostic tool of the multiple processes taking place in it. The science that X-rays reveal encompasses solar, space plasma and planetary physics, and the response of bodies in the solar system to the impact of the Sun's activity. This talk will review what we know from past observations and what we expect to learn in the short, medium and long term. Observations with Chandra and XMM-Newton have demonstrated that the origin of Jupiter's bright soft X-ray aurorae lies in the Charge eXchange (CX) process, likely to involve the interaction with atmospheric neutrals of local magnetospheric ions, as well as those carried in the solar wind. At higher energies electron bremsstrahlung is thought to be the X-ray emitting mechanism, while the whole planetary disk acts as a mirror for the solar X-ray flux via Thomson and fluorescent scattering. This 'X-ray mirror' phenomenon is all that is observed from Saturn's disk, which otherwise lacks X-ray auroral features. The Earth's X-ray aurora is bright and variable and mostly due to electron bremsstrahlung and line emission from atmospheric species. Un-magnetised planets, Venus and Mars, do not show X-ray aurorae but display the interesting combination of mirroring the solar X-ray flux and producing X-rays by Solar Wind Charge eXchange (SWCX) in their exospheres. These processes respond to different solar stimulation (photons and solar wind plasma respectively) hence their relative contributions are seen to vary according to the Sun's output. Present and future of planetary X-ray studies are very bright. We are preparing for the arrival of the Juno mission at Jupiter this summer and for coordinated observations with Chandra and XMM-Newton on the approach and later during Juno's orbital phase. These will allow direct correlation of the local plasma conditions with the X-ray emissions and the establishment of the

  17. Mechanistic Studies of Planetary Haze Formation

    Science.gov (United States)

    Hicks, Raea Kay

    2015-10-01

    Planetary atmospheres can be thought of as global-scale reactors capable of synthesizing large, complex molecules from small gases such as methane (CH4), carbon dioxide (CO2), and nitrogen (N2). The atmosphere of Titan, the largest moon of Saturn covered by a thick organic haze, contains trace amounts (2%) of CH4 in an atmosphere of N2 at a surface pressure of 1.5 bar. This is similar to the Earth's Archaean atmosphere, which possibly contained trace amounts of CH4 and CO2 (˜1,000 ppmv each) in an N2 -dominant atmosphere before the rise of biogenic oxygen. Laboratory simulations of the atmospheric chemistry on Titan and the early Earth have shown that these atmospheres are capable of generating biologically-relevant molecules that condense to form particles which can then settle to the surface of the planetary body, possibly providing the molecules required for the emergence of life. The work presented here examines the mechanisms by which FUV photochemistry initiates incorporation of N atoms into Titan aerosol analogs, and C atoms into early Earth aerosol analogs. Results from the Aerosol Collector and Pyrolyser onboard the Huygens lander reveal the presence of nitrogen in Titan's aerosols. This nitrogen incorporation is thought to occur primarily by extreme-UV photons or energetic electrons. However, recent results from our laboratory indicate a surprising amount of nitrogen incorporation- up to 16% by mass- in Titan aerosol analogs produced by photochemistry initiated by FUV irradiation of CH4/N 2 mixtures. The termolecular reaction CH+N2 +M → HCN2 has been proposed to account for this observation. Here, we test this hypothesis by using a high- resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) to measure the mass loading and chemical composition of aerosol produced at a range of pressures from roughly 0.1 to 1 atm. We report a 10-fold increase in aerosol mass loading across the range of pressures studied, indicating that the mechanism

  18. The AFCRL Lunar amd Planetary Research Branch

    Science.gov (United States)

    Price, Stephan D.

    2011-07-01

    The Lunar and Planetary research program led by Dr John (Jack) Salisbury in the 1960s at the United States Air Force Cambridge Research Laboratories (AFCRL) investigated the surface characteristics of Solar System bodies. The Branch was one of the first groups to measure the infrared spectra of likely surface materials in the laboratory under appropriate vacuum and temperature conditions. The spectral atlases created from the results were then compared to photometric and spectral measurements obtained from ground- and balloon-based telescopes to infer the mineral compositions and physical conditions of the regoliths of the Moon, Mars and asteroids. Starting from scratch, the Branch initially sponsored observations of other groups while its in-house facilities were being constructed. The earliest contracted efforts include the spatially-resolved mapping of the Moon in the first half of the 1960s by Richard W. Shorthill and John W. Saari of the Boeing Scientific Research Laboratories in Seattle. This effort ultimately produced isophotal and isothermal contour maps of the Moon during a lunation and time-resolved thermal images of the eclipsed Moon. The Branch also sponsored probe rocket-based experiments flown by Riccardo Giacconi and his group at American Science and Engineering Inc. that produced the first observations of X-ray stars in 1962 and later the first interferometric measurement of the ozone and C02 emission in the upper atmosphere. The Branch also made early use of balloon-based measurements. This was a singular set of experiments, as these observations are among the very few mid-infrared astronomical measurements obtained from a balloon platform. Notable results of the AFCRL balloon flights were the mid-infrared spectra of the spatially-resolved Moon obtained with the University of Denver mid-infrared spectrometer on the Branch's balloon-borne 61-cm telescope during a 1968 flight. These observations remain among the best available. Salisbury also funded

  19. Origins of Structure in Planetary Systems

    Science.gov (United States)

    Murray-Clay, Ruth

    2016-01-01

    Observations confirm that planet formation is a ubiquitous process that produces a diversity of planetary systems. However, a class of solar system analogs has yet to be identified among the thousands of currently known planets and candidates, the overwhelming majority of which are more easily detectable than direct counterparts of the Sun's worlds. To understand whether our solar system's history was unusual and, more generally, to properly characterize the galactic population of extrasolar planets, we must identify how differences in formation environment translate into different planetary system architectures. In this talk, I will consider our solar system in the context of theoretical advances in planet formation driven by the study of extrasolar planets. Along the way, I will discuss several examples of physical processes operating at different stages of planet formation that imprint observable structures on the dynamical and compositional demographics of planetary systems.

  20. Magnetic investigations for studying planetary interiors

    Directory of Open Access Journals (Sweden)

    A. De Santis

    1994-06-01

    Full Text Available Most of the magnetic methods used for investigating planetary interiors are based on the reasonable hypothesis that the mechanism for the origin of the field is an Earth-like hydromagnetic dynamo: in this case the planet has an electrically conducting fluid shell within it as in the case of the Earth's core. The present paper describes several techniques of planetary magnetic investigation which give important clues on the internal constitution of planets. Some considerations on the possible mechanisms for maintaining a dynamo and simple concepts with the help of a few non-dimensional numbers are also introduced and discussed. Then some fundamental relationships are given in order to relate the planetary magnetism to other physical parameters, such as angular rotation, core dimensions etc. It finally summarizes some results available for the planets of the Solar System.

  1. Energy Balance Models and Planetary Dynamics

    Science.gov (United States)

    Domagal-Goldman, Shawn

    2012-01-01

    We know that planetary dynamics can have a significant affect on the climate of planets. Planetary dynamics dominate the glacial-interglacial periods on Earth, leaving a significant imprint on the geological record. They have also been demonstrated to have a driving influence on the climates of other planets in our solar system. We should therefore expect th.ere to be similar relationships on extrasolar planets. Here we describe a simple energy balance model that can predict the growth and thickness of glaciers, and their feedbacks on climate. We will also describe model changes that we have made to include planetary dynamics effects. This is the model we will use at the start of our collaboration to handle the influence of dynamics on climate.

  2. Body Odor

    Science.gov (United States)

    ... Health Medical Conditions Nutrition & Fitness Emotional Health Body Odor Posted under Health Guides . Updated 29 October 2014. + ... guy has to deal with. What causes body odor? During puberty, your sweat glands become much more ...

  3. Body Hygiene

    Science.gov (United States)

    ... Home Diaper-Changing Steps for Childcare Settings Body Hygiene Dental Hygiene Water Fluoridation Facial Cleanliness Fish Pedicures and ... spread of hygiene-related diseases . Topics for Body Hygiene Facial Cleanliness Dental Hygiene Water Fluoridation Fish Pedicures and Fish Spas ...

  4. Body Image

    Science.gov (United States)

    ... Help your child have a healthy body image Cosmetic surgery Breast surgery Botox Liposuction Varicose or spider veins Body dysmorphic disorder (BDD) Eating disorders Anorexia nervosa Binge eating ... nervosa Cosmetics and your health Depression during and after pregnancy ...

  5. Body Basics

    Science.gov (United States)

    ... about how the body works, what basic human anatomy is, and what happens when parts of the body don't function properly. Blood Bones, Muscles, and Joints Brain and Nervous System Digestive System Endocrine System Eyes Female Reproductive System ...

  6. Temperature-time issues in bioburden control for planetary protection

    Science.gov (United States)

    Clark, Benton C.

    2004-01-01

    Heat energy, administered in the form of an elevated temperature heat soak over a specific interval of time, is a well-known method for inactivating organisms. Sterilization protocols, from commercial pasteurization to laboratory autoclaving, specify both temperature and time, as well as water activity, for treatments to achieve either acceptable reduction of bioburden or complete sterilization. In practical applications of planetary protection, whether to reduce spore load in forward or roundtrip contamination, or to exterminate putative organisms in returned samples from bodies suspected of possible life, avoidance of expensive or potentially damaging treatments of hardware (or samples) could be accomplished if reciprocal relationships between time duration and soak temperature could be established. Conservative rules can be developed from consideration of empirical test data, derived relationships, current standards and various theoretical or proven mechanisms for thermal damage to biological systems.

  7. Relating binary-star planetary systems to central configurations

    CERN Document Server

    Veras, Dimitri

    2016-01-01

    Binary-star exoplanetary systems are now known to be common, for both wide and close binaries. However, their orbital evolution is generally unsolvable. Special cases of the N-body problem which are in fact completely solvable include dynamical architectures known as central configurations. Here, I utilize recent advances in our knowledge of central configurations to assess the plausibility of linking them to coplanar exoplanetary binary systems. By simply restricting constituent masses to be within stellar or substellar ranges characteristic of planetary systems, I find that (i) this constraint reduces by over 90 per cent the phase space in which central configurations may occur, (ii) both equal-mass and unequal-mass binary stars admit central configurations, (iii) these configurations effectively represent different geometrical extensions of the Sun-Jupiter-Trojan-like architecture, (iv) deviations from these geometries are no greater than ten degrees, and (v) the deviation increases as the substellar masse...

  8. Formation, Orbital and Internal Evolutions of Young Planetary Systems

    CERN Document Server

    Baruteau, Clément; Mordasini, Christoph; Mollière, Paul

    2016-01-01

    The growing body of observational data on extrasolar planets and protoplanetary disks has stimulated intense research on planet formation and evolution in the past few years. The extremely diverse, sometimes unexpected physical and orbital characteristics of exoplanets lead to frequent updates on the mainstream scenarios for planet formation and evolution, but also to the exploration of alternative avenues. The aim of this review is to bring together classical pictures and new ideas on the formation, orbital and internal evolutions of planets, highlighting the key role of the protoplanetary disk in the various parts of the theory. We begin by briefly reviewing the conventional mechanism of core accretion by the growth of planetesimals, and discuss a relatively recent model of core growth through the accretion of pebbles. We review the basic physics of planet-disk interactions, recent progress in this area, and discuss their role in observed planetary systems. We address the most important effects of planets i...

  9. Dynamical Tides and Oscillations in Star and Planetary Systems

    Science.gov (United States)

    Fuller, Jim

    2015-04-01

    The oscillations of stars and planets are a powerful tool for understanding the structure and evolution of these bodies. In compact white dwarf (WD) binaries, tidally excited waves within the WDs deposit energy and angular momentum within the WDs, producing strong tidal dissipation. The tidal torque spins up the WDs such that they are nearly synchronously rotating by the onset of mass transfer. Tidal heating may make the WDs more luminous by orders of magnitude, and it could even reignite thermonuclear fusion in the WD's hydrogen shell. In various types of star systems observed by Kepler, tidally excited oscillations are detectable and provide direct constraints on tidal dissipation rates in these systems. Finally, in the planet Saturn, planetary oscillation modes have been detected via their gravitational influence on the rings. The frequencies of the modes allow for the first seismic constraints on a planet other than the Earth, and they provide evidence for non-conventional structures within Saturn.

  10. Detection of the Water Reservoir in a Forming Planetary System

    CERN Document Server

    Hogerheijde, Michiel R; Brinch, Christian; Cleeves, L Ilsedore; Fogel, Jeffrey K J; Blake, Geoffrey A; Dominik, Carsten; Lis, Dariusz C; Melnick, Gary; Neufeld, David; Panic, Olja; Pearson, John C; Kristensen, Lars; Yildiz, Umut A; van Dishoeck, Ewine F

    2011-01-01

    Icy bodies may have delivered the oceans to the early Earth, yet little is known about water in the ice-dominated regions of extra-solar planet-forming disks. The Heterodyne Instrument for the Far-Infrared on-board the Herschel Space Observatory has detected emission from both spin isomers of cold water vapor from the disk around the young star TW Hydrae. This water vapor likely originates from ice-coated solids near the disk surface hinting at a water ice reservoir equivalent to several thousand Earth Oceans in mass. The water's ortho-to-para ratio falls well below that of Solar System comets, suggesting that comets contain heterogeneous ice mixtures collected across the entire solar nebula during the early stages of planetary birth.

  11. Containment of a diffuse ionized mass orbiting around a magnetized central body

    International Nuclear Information System (INIS)

    The containment of a diffused and ionized mass orbiting around a magnetized central body is studied and the condition equation is established. Some qualitative and quantitative applications to the planetary cosmogony problems are developed. (Auth.)

  12. Body embellishment

    OpenAIRE

    Zellweger, Christoph

    2015-01-01

    The exhibition Body Embellishment explores the most innovative artistic expression in the 21st-century international arenas of body extension, augmentation, and modification, focusing on jewelry, tattoos, nail arts, and fashion. The areas of focus are jewelry, tattoos, nail arts, and fashion. Avant-garde jewelry consciously engages the body by intersecting and expanding the planes of the human form. Tattoos are at once on and in the body. Nail art, from manicures to pedicures, has humble ...

  13. Body Clock

    Institute of Scientific and Technical Information of China (English)

    刘洪毓

    2000-01-01

    Body clocks” are biological methods of controling body activities.Every living thing has one. In humans, a body clock controls normal periods of sleeping and waking. It controls the time swhen you are most likely to feel pain.Eating, sleeping and exercising at about the same time each day will help keep body activities normal. But changes in your life, a new job, for example, destroy the balance and thus cause health problems.

  14. Mission Implementation Constraints on Planetary Muon Radiography

    Science.gov (United States)

    Jones, Cathleen E.; Kedar, Sharon; Naudet, Charles; Webb, Frank

    2011-01-01

    Cost: Use heritage hardware, especially use a tested landing system to reduce cost (Phoenix or MSL EDL stage). The sky crane technology delivers higher mass to the surface and enables reaching targets at higher elevation, but at a higher mission cost. Rover vs. Stationary Lander: Rover-mounted instrument enables tomography, but the increased weight of the rover reduces the allowable payload weight. Mass is the critical design constraint for an instrument for a planetary mission. Many factors that are minor factors or do not enter into design considerations for terrestrial operation are important for a planetary application. (Landing site, diurnal temperature variation, instrument portability, shock/vibration)

  15. Directed Energy Missions for Planetary Defense

    OpenAIRE

    Lubin, Philip; Hughes, Gary B.; Eskenazi, Mike; Kosmo, Kelly; Johansson, Isabella E.; Griswold, Janelle; Pryor, Mark; O'Neill, Hugh,; Meinhold, Peter; Suen, Jonathon; Riley, Jordan; Zhang, Qicheng; Walsh, Kevin; Melis, Carl; Kangas, Miikka

    2016-01-01

    Directed energy for planetary defense is now a viable option and is superior in many ways to other proposed technologies, being able to defend the Earth against all known threats. This paper presents basic ideas behind a directed energy planetary defense system that utilizes laser ablation of an asteroid to impart a deflecting force on the target. A conceptual philosophy called DE-STAR, which stands for Directed Energy System for Targeting of Asteroids and exploRation, is an orbiting stand-of...

  16. Insights into planet formation from debris disks: II. Giant impacts in extrasolar planetary systems

    OpenAIRE

    Wyatt, Mark C.; Jackson, Alan P.

    2016-01-01

    Giant impacts refer to collisions between two objects each of which is massive enough to be considered at least a planetary embryo. The putative collision suffered by the proto-Earth that created the Moon is a prime example, though most Solar System bodies bear signatures of such collisions. Current planet formation models predict that an epoch of giant impacts may be inevitable, and observations of debris around other stars are providing mounting evidence that giant impacts feature in the ev...

  17. Accretion of Uranus and Neptune from inward-migrating planetary embryos blocked by Jupiter and Saturn

    OpenAIRE

    Izidoro, Andre; Morbidelli, Alessandro; Raymond, Sean N.; Hersant, Franck; Pierens, Arnaud

    2015-01-01

    Reproducing Uranus and Neptune remains a challenge for simulations of solar system formation. The ice giants' peculiar obliquities suggest that they both suffered giant collisions during their formation. Thus, there must have been an epoch of accretion dominated by collisions among large planetary embryos in the primordial outer solar system. We test this idea using N-body numerical simulations including the effects of a gaseous protoplanetary disk. One strong constraint is that the masses of...

  18. Why are dense planetary rings only found between 8 and 20 AU?

    OpenAIRE

    Hedman, M. M.

    2015-01-01

    The recent discovery of dense rings around the Centaur Chariklo (and possibly Chiron) reveals that complete dense planetary rings are not only found around Saturn and Uranus, but also around small bodies orbiting in the vicinity of those giant planets. This report examines whether there could be a physical process that would make rings more likely to form or persist in this particular part of the outer Solar System. Specifically, the ring material orbiting Saturn and Uranus appears to be much...

  19. New Discoveries in Planetary Systems and Star Formation through Advances in Laboratory Astrophysics

    OpenAIRE

    WGLA, AAS; Brickhouse, Nancy; Cowan, John; Drake, Paul; Federman, Steven; Ferland, Gary; Frank, Adam; Herbst, Eric; Olive, Keith(School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, 55455, U.S.A.); Salama, Farid; Savin, Daniel Wolf; Ziurys, Lucy

    2009-01-01

    As the panel on Planetary Systems and Star Formation (PSF) is fully aware, the next decade will see major advances in our understanding of these areas of research. To quote from their charge, these advances will occur in studies of solar system bodies (other than the Sun) and extrasolar planets, debris disks, exobiology, the formation of individual stars, protostellar and protoplanetary disks, molecular clouds and the cold ISM, dust, and astrochemistry. Central to the progress in these areas ...

  20. Planetary Accretion in the Inner Solar System: Dependence on Nebula Surface Density Profile and Giant Planet Eccentricities

    Science.gov (United States)

    Chambers, J. E.; Cassen, P.

    2002-01-01

    We present 32 N-body simulations of planetary accretion in the inner Solar System, examining the effect of nebula surface density profile and initial eccentricities of Jupiter and Saturn on the compositions and orbits of the inner planets. Additional information is contained in the original extended abstract.

  1. Magnetic evidence for a partially differentiated carbonaceous chondrite parent body

    OpenAIRE

    Carporzen, Laurent; Weiss, Benjamin P.; Elkins-Tanton, Linda T.; Shuster, David L.; Ebel, Denton; Gattacceca, Jérôme

    2011-01-01

    The textures of chondritic meteorites demonstrate that they are not the products of planetary melting processes. This has long been interpreted as evidence that chondrite parent bodies never experienced large-scale melting. As a result, the paleomagnetism of the CV carbonaceous chondrite Allende, most of which was acquired after accretion of the parent body, has been a long-standing mystery. The possibility of a core dynamo like that known for achondrite parent bodies has been discounted beca...

  2. Brownian Motion in Planetary Migration

    CERN Document Server

    Murray-Clay, R A; Murray-Clay, Ruth A.; Chiang, Eugene I.

    2006-01-01

    A residual planetesimal disk of mass 10-100 Earth masses remained in the outer solar system following the birth of the giant planets, as implied by the existence of the Oort cloud, coagulation requirements for Pluto, and inefficiencies in planet formation. Upon gravitationally scattering planetesimal debris, planets migrate. Orbital migration can lead to resonance capture, as evidenced here in the Kuiper and asteroid belts, and abroad in extra-solar systems. Finite sizes of planetesimals render migration stochastic ("noisy"). At fixed disk mass, larger (fewer) planetesimals generate more noise. Extreme noise defeats resonance capture. We employ order-of-magnitude physics to construct an analytic theory for how a planet's orbital semi-major axis fluctuates in response to random planetesimal scatterings. To retain a body in resonance, the planet's semi-major axis must not random walk a distance greater than the resonant libration width. We translate this criterion into an analytic formula for the retention effi...

  3. NASA’S PLANETARY GEOLOGIC MAPPING PROGRAM: OVERVIEW

    OpenAIRE

    Williams, D.A.

    2016-01-01

    NASA’s Planetary Science Division supports the geologic mapping of planetary surfaces through a distinct organizational structure and a series of research and analysis (R&A) funding programs. Cartography and geologic mapping issues for NASA’s planetary science programs are overseen by the Mapping and Planetary Spatial Infrastructure Team (MAPSIT), which is an assessment group for cartography similar to the Mars Exploration Program Assessment Group (MEPAG) for Mars exploration. MAPSIT...

  4. Planetary protection in the framework of the Aurora exploration program

    Science.gov (United States)

    Kminek, G.

    The Aurora Exploration Program will give ESA new responsibilities in the field of planetary protection. Until now, ESA had only limited exposure to planetary protection from its own missions. With the proposed ExoMars and MSR missions, however, ESA will enter the realm of the highest planetary protection categories. As a consequence, the Aurora Exploration Program has initiated a number of activities in the field of planetary protection. The first and most important step was to establish a Planetary Protection Working Group (PPWG) that is advising the Exploration Program Advisory Committee (EPAC) on all matters concerning planetary protection. The main task of the PPWG is to provide recommendations regarding: Planetary protection for robotic missions to Mars; Planetary protection for a potential human mission to Mars; Review/evaluate standards & procedures for planetary protection; Identify research needs in the field of planetary protection. As a result of the PPWG deliberations, a number of activities have been initiated: Evaluation of the Microbial Diversity in SC Facilities; Working paper on legal issues of planetary protection and astrobiology; Feasibility study on a Mars Sample Return Containment Facility; Research activities on sterilization procedures; Training course on planetary protection (May, 2004); Workshop on sterilization techniques (fall 2004). In parallel to the PPWG, the Aurora Exploration Program has established an Ethical Working Group (EWG). This working group will address ethical issues related to astrobiology, planetary protection, and manned interplanetary missions. The recommendations of the working groups and the results of the R&D activities form the basis for defining planetary protection specification for Aurora mission studies, and for proposing modification and new inputs to the COSPAR planetary protection policy. Close cooperation and free exchange of relevant information with the NASA planetary protection program is strongly

  5. A Herschel study of Planetary Nebulae

    CERN Document Server

    Van de Steene, G C; van Hoof, P A M; Lim, T L; Barlow, M J; Matsuura, M; Ueta, T

    2011-01-01

    We present Herschel PACS and SPIRE images of the dust shells around the planetary nebulae NGC 650, NGC 6853, and NGC 6720, as well as images showing the dust temperature in their shells. The latter shows a rich structure, which indicates that internal extinction in the UV is important despite the highly evolved status of the nebulae.

  6. Planetary Nebulae as Mass Tracers in Galaxies

    OpenAIRE

    Romanowsky, Aaron J.

    2006-01-01

    Planetary nebula are useful kinematic tracers of the stars in all galaxy types. I review recent observationally-driven developments in the study of galaxy mass profiles. These have yielded surprising results on spiral galaxy disk masses and elliptical galaxy halo masses. A key remaining question is the coupling between PNe and the underlying stellar populations.

  7. 3-D structures of planetary nebulae

    CERN Document Server

    Steffen, Wolfgang

    2016-01-01

    Recent advances in the 3-D reconstruction of planetary nebulae are reviewed. We include not only results for 3-D reconstructions, but also the current techniques in terms of general methods and software. In order to obtain more accurate reconstructions, we suggest to extend the widely used assumption of homologous nebula expansion to map spectroscopically measured velocity to position along the line of sight.

  8. Spatial spectroscopic diagnostics of planetary nebulae. VI

    International Nuclear Information System (INIS)

    The numerical properties of the kernel function of the Fredholm integral equation of the first kind of spatial spectroscopic diagnostics of planetary nebulae, are studied and briefly discussed. Samples of some kernel functions are shown as three-dimensional axonometric figures. A simple reason is given for inherent limitations of the regularization techniques used. (author). 12 figs., 2 refs

  9. Detection techniques for tenuous planetary atmospheres

    Science.gov (United States)

    Hoenig, S. A.

    1972-01-01

    The research for the development of new types of detectors for analysis of planetary atmospheres is summarized. Topics discussed include: corona discharge humidity detector, surface catalysis and exo-electron emission, and analysis of soil samples by means of exo-electron emission. A report on the exo-electron emission during heterogeneous catalysis is included.

  10. Fullerenes and the Nature of Planetary Gases

    Science.gov (United States)

    Becker, Luann; Poreda, Robert J.; Nuth, Joe

    2003-01-01

    Over the past several decades, two issues have dominated the discussion of planetary noble gas patterns: 1) the general resemblance of the noble gas abundances in carbonaceous chondrites to those measured in the Earth s atmosphere and; 2) atmospheric inventories of argon and neon that fall off significantly with increasing distance from the Sun. The recognition of the latter has led to the conclusion that the planetary component is not found on planets. In particular, the inability to explain the missing xenon reservoir, once thought to be sequestered in crustal rocks has been extremely troublesome. Some models have focused on various fractionations of solar wind rather than condensation as the process for the evolution of noble gases in the terrestrial planets. However, these models cannot explain the observed gradient of the gases, nor do they account for the similar Ne/Ar ratios and the dissimilar planetary Ar/Kr ratios. More recent studies have focused on hydrodynamic escape to explain the fractionation of gases, like neon, in the atmosphere and the mantle. Escape theory also seems to explain, in part, the isotopically heavy argon on Mars, however, it does not explain the discrepancies observed for the abundances of argon and neon on Venus and the Earth. This has led to the assumption that some combination of solar wind implantation, absorption and escape are needed to explain the nature of planetary noble gases.

  11. NASA Planetary Science Summer School: Longitudinal Study

    Science.gov (United States)

    Giron, Jennie M.; Sohus, A.

    2006-12-01

    NASA’s Planetary Science Summer School is a program designed to prepare the next generation of scientists and engineers to participate in future missions of solar system exploration. The opportunity is advertised to science and engineering post-doctoral and graduate students with a strong interest in careers in planetary exploration. Preference is given to U.S. citizens. The “school” consists of a one-week intensive team exercise learning the process of developing a robotic mission concept into reality through concurrent engineering, working with JPL’s Advanced Project Design Team (Team X). This program benefits the students by providing them with skills, knowledge and the experience of collaborating with a concept mission design. A longitudinal study was conducted to assess the impact of the program on the past participants of the program. Data collected included their current contact information, if they are currently part of the planetary exploration community, if participation in the program contributed to any career choices, if the program benefited their career paths, etc. Approximately 37% of 250 past participants responded to the online survey. Of these, 83% indicated that they are actively involved in planetary exploration or aerospace in general; 78% said they had been able to apply what they learned in the program to their current job or professional career; 100% said they would recommend this program to a colleague.

  12. Transiting planetary system WASP-17 (Southworth+, 2012)

    DEFF Research Database (Denmark)

    Southworth, J.; Hinse, T. C.; Dominik, M.;

    2013-01-01

    A light curve of four transits of the extrasolar planetary system WASP-17 is presented. The data were obtained using the Danish 1.5m telescope and DFOSC camera at ESO La Silla in 2012, with substantial telescope defocussing in order to improve the photometric precision of the observations. A Cous...

  13. The virial theorem and planetary atmospheres

    OpenAIRE

    Toth, Viktor T.

    2010-01-01

    We derive a version of the virial theorem that is applicable to diatomic planetary atmospheres that are in approximate thermal equilibrium at moderate temperatures and pressures and are sufficiently thin such that the gravitational acceleration can be considered constant. We contrast a pedagogically inclined theoretical presentation with the actual measured properties of air.

  14. Geomorphological processes on terrestrial planetary surfaces

    OpenAIRE

    Sharp, Robert P.

    1980-01-01

    This review deals with features and processes on planetary surfaces, first by examining the impact of photographic explorations of Moon, Mars, and Mercury on studies of surface processes on our own planet, and second by treating matters related to current deformation of Earth’s surface.

  15. The History of Planetary Exploration Using Mass Spectrometers

    Science.gov (United States)

    Mahaffy, Paul R.

    2012-01-01

    At the Planetary Probe Workshop Dr. Paul Mahaffy will give a tutorial on the history of planetary exploration using mass spectrometers. He will give an introduction to the problems and solutions that arise in making in situ measurements at planetary targets using this instrument class.

  16. Numerical modeling of protocore destabilization during planetary accretion: Methodology and results

    Science.gov (United States)

    Lin, Ja-Ren; Gerya, Taras V.; Tackley, Paul J.; Yuen, David A.; Golabek, Gregor J.

    2009-12-01

    We developed and tested an efficient 2D numerical methodology for modeling gravitational redistribution processes in a quasi spherical planetary body based on a simple Cartesian grid. This methodology allows one to implement large viscosity contrasts and to handle properly a free surface and self-gravitation. With this novel method we investigated in a simplified way the evolution of gravitationally unstable global three-layer structures in the interiors of large metal-silicate planetary bodies like those suggested by previous models of cold accretion [Sasaki, S., Nakazawa, K., 1986. J. Geophys. Res. 91, 9231-9238; Karato, S., Murthy, V.R., 1997. Phys. Earth Planet Interios 100, 61-79; Senshu, H., Kuramoto, K., Matsui, T., 2002. J. Geophys. Res. 107 (E12), 5118. 10.1029/2001JE001819]: an innermost solid protocore (either undifferentiated or partly differentiated), an intermediate metal-rich layer (either continuous or disrupted), and an outermost silicate-rich layer. Long-wavelength (degree-one) instability of this three-layer structure may strongly contribute to core formation dynamics by triggering planetary-scale gravitational redistribution processes. We studied possible geometrical modes of the resulting planetary reshaping using scaled 2D numerical experiments for self-gravitating planetary bodies with Mercury-, Mars- and Earth-size. In our simplified model the viscosity of each material remains constant during the experiment and rheological effects of gravitational energy dissipation are not taken into account. However, in contrast to a previously conducted numerical study [Honda, R., Mizutani, H., Yamamoto, T., 1993. J. Geophys. Res. 98, 2075-2089] we explored a freely deformable planetary surface and a broad range of viscosity ratios between the metallic layer and the protocore (0.001-1000) as well as between the silicate layer and the protocore (0.001-1000). An important new prediction from our study is that realistic modes of planetary reshaping

  17. Inductive heating and quenching of planetary shafts

    Directory of Open Access Journals (Sweden)

    B. Kosec

    2010-04-01

    Full Text Available Purpose: High mechanical and temperature cyclic loading of the final products for automotive, construction, transport and agriculture mechanization industry, demands sufficient mechanical properties of all of their components during its exploitation. Majority of the components is made from steel, by different cold forming processes. Their main demanded characteristics are surface wear resistance and fatigue strength under pulsating stress in combination with cyclic temperature loading, which could be achieved only by appropriate heat treatment.Design/methodology/approach: In the experimental part of our work, the efficiency of the combined inductive heating and water quenching heat treatment and quality of the planetary shafts were analyzed, with the use of thermographic analysis, hardness measurements, and metallographic examination.Findings: Combination of inductive heating and water quenching is the most effective heat treatment process of carbon steel planetary shafts for the diesel engine starters.Research limitations/implications: Long life span of carbon steel planetary shafts it's essential for their economical production. The replacement of starter is expensive from both: money and working time point of view.Practical implications: Surface temperature measurements during the inductive heating process were realized in the industrial environment. The intensity and homogeneity of the planetary shaft surface temperature field was measured by thermographic camera.Originality/value: On the base of theoretical knowledge and measurements, a mathematical model for temperature conditions determination in the shaft during the entire process of heating and quenching was carried out. On the basis of developed mathematical model a computer program was worked out, and used for analyses and optimization of planetary shafts induction hardening process.

  18. Exo-Planetary Phoenix: Rebirth of Planetary Systems Beyond the Main Sequence

    Science.gov (United States)

    Marengo, M.

    2014-04-01

    Mounting evidence suggests that planetary systems may be a common feature of stars that have evolved beyond the main sequence. Warm debris disks around white dwarfs and "pulsar" planets orbiting a neutron star are a strong indication that planetary systems may, at least in same cases, survive the dramatic phenomena leading to stellar death. A close look at these late evolutionary stages, however, suggests that these systems may be more than mere survivors of doomed pre-existing exo-planetary systems. The circumstellar environment of post-main sequence stars bears surprising similarities to the conditions leading to pre-main sequence planetary formation: a metal-rich environment often characterized by the presence of circumstellar or circumbinary disks. Are these conditions conducive to the birth of a second-generation planetary system, like a phoenix rising from the ashes of ancient worlds? In this talk we will discuss how the physical conditions in the winds of dusty giant stars may be favorable for renewed planetary formation, with particular emphasis on the effects of enhanced metallicity, binarity and the timescales available for the formation of a new generation of planets.

  19. Planetary Science with Balloon-Borne Telescopes: A Summary of the BOPPS Mission and the Planetary Science that may be Possible Looking Forward

    Science.gov (United States)

    Kremic, T.; Cheng, A.; Hibbitts, K.; Young, E. F.

    2015-09-01

    The National Aeronautics and Space Administration (NASA) and the planetary science community have recently been exploring the potential contributions of stratospheric balloons to the planetary science field. A study that was recently concluded explored the roughly 200 or so science questions raised in the Planetary Decadal Survey report and found that about 45 of those questions are suited to stratospheric balloon based observations. In September of 2014, a stratospheric balloon mission called BOPPS (which stands for Balloon Observation Platform for Planetary Science) was flown out of Fort Sumner, New Mexico. The mission had two main objectives, first, to observe a number of planetary targets including one or more Oort cloud comets and second, to demonstrate the applicability and performance of the platform, instruments, and subsystems for making scientific measurements in support of planetary science objectives. BOPPS carried two science instruments, BIRC and UVVis. BIRC is a cryogenic infrared multispectral imager which can image in the 0.6-5 ~im range using an HgCdTe detector. Narrow band filters were used to allow detection of water and CO2 emission features of the observed targets. The UVVis is an imager with the science range of 300 to 600 nm. A main feature of the UVVis instrument is the incorporation of a guide camera and a Fine-Steering Mirror (FSM) system to reduce image jitter to less than 100 milliarcsecond. The BIRC instrument was used to image targets including Oort cloud comets Siding Spring and Jacques, and the dwarf planet 1 Ceres. BOPPS achieved the first ever earth based CO2 observation of a comet and the first images of water and CO2 of an Oort cloud comet (Jacques). It also made the first ever measurement of 1 Ceres at 2.73 ~tm to refine the shape of the infrared water absorption feature on that body. The UVVis instrument, mounted on its own optics bench, demonstrated the capability for image correction both from atmospheric disturbances as

  20. On possible circumbinary configurations of the planetary systems of α Centauri and EZ Aquarii

    Science.gov (United States)

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

    2016-04-01

    Possible configurations of the planetary systems of the binary stars α Cen A-BandEZAqr A-C are analyzed. The P-type orbits—circumbinary ones, i.e., the orbits around both stars of the binary, are studied. The choice of these systems is dictated by the fact that α Cen is closest to us in the Galaxy, while EZ Aqr is the closest system whose circumbinary planets, as it turns out, may reside in the "habitability zone." The analysis has been performed within the framework of the planar restricted three-body problem. The stability diagrams of circumbinary motion have been constructed: on representative sets of initial data (in the pericentric distance-eccentricity plane), we have computed the Lyapunov spectra of planetary motion and identified the domains of regular and chaotic motion through their statistical analysis. Based on present views of the dynamics and architecture of circumbinary planetary systems, we have determined the most probable planetary orbits to be at the centers of the main resonance cells, at the boundary of the dynamical chaos domain around the parent binary star, which allows the semimajor axes of the orbits to be predicted. In the case of EZ Aqr, the orbit of the circumbinary planet is near the habitability zone and, given that the boundary of this zone is uncertain, may belong to it.

  1. Accretion of Uranus and Neptune from inward-migrating planetary embryos blocked by Jupiter and Saturn

    CERN Document Server

    Izidoro, Andre; Raymond, Sean N; Hersant, Franck; Pierens, Arnaud

    2015-01-01

    Reproducing Uranus and Neptune remains a challenge for simulations of solar system formation. The ice giants' peculiar obliquities suggest that they both suffered giant collisions during their formation. Thus, there must have been an epoch of accretion dominated by collisions among large planetary embryos in the primordial outer solar system. We test this idea using N-body numerical simulations including the effects of a gaseous protoplanetary disk. One strong constraint is that the masses of the ice giants are very similar -- the Neptune/Uranus mass ratio is $\\sim1.18$. We show that similar-size ice giants do indeed form by collisions between planetary embryos beyond Saturn. The fraction of successful simulations varies depending on the initial number of planetary embryos in the system, their individual and total masses. Similar-sized ice giants are consistently reproduced in simulations starting with 5-10 planetary embryos with initial masses of $\\sim$3-6 ${\\rm M_\\oplus}$. We conclude that accretion from a ...

  2. Planetary Protection Concerns During Pre-Launch Radioisotope Power System Final Integration Activities

    Science.gov (United States)

    Chen, Fei; McKay, Terri; Spry, James A.; Colozza, Anthony J.; DiStefano, Salvador

    2012-01-01

    The Advanced Stirling Radioisotope Generator (ASRG) is a next-generation radioisotope-based power system that is currently being developed as an alternative to the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). Power sources such as these may be needed for proposed missions to solar system planets and bodies that have challenging Planetary Protection (PP) requirements (e.g. Mars, Europa, Enceladus) that may support NASA s search for life, remnants of past life, and the precursors of life. One concern is that the heat from the ASRG could potentially create a region in which liquid water may occur. As advised by the NASA Planetary Protection Officer, when deploying an ASRG to Mars, the current COSPAR/NASA PP policy should be followed for Category IVc mission. Thus, sterilization processing of the ASRG to achieve bioburden reduction would be essential to meet the Planetary Protection requirements. Due to thermal constraints and associated low temperature limits of elements of the ASRG, vapor hydrogen peroxide (VHP) was suggested as a candidate alternative sterilization process to complement dry heat microbial reduction (DHMR) for the assembled ASRG. The following proposed sterilization plan for the ASRG anticipates a mission Category IVc level of cleanliness. This plan provides a scenario in which VHP is used as the final sterilization process. Keywords: Advanced Stirling Radioisotope Generator (ASRG), Planetary Protection (PP), Vapor hydrogen peroxide (VHP) sterilization.

  3. Modeling of the process of gear shifting in planetary gear trains of motor vehicles

    Directory of Open Access Journals (Sweden)

    Aleksandar R. Grkić

    2011-04-01

    scheme of the gear train. The gears are presented as a solid body defined by mass, moment of inertia, position with respect to the system and the center of gravity. Subsystem for monitoring the simulation results Measuring and recording the simulation results are simulated with the simulation tracking subsystem. The simulation results are described through the torque and the angular velocity as a function of time. Analysis of the simulation model Forming a simulation model enables virtual testing of the planetary gear and the analysis of the impact of certain parameters on the behavior of the gear during gear changes. In other words, an opportunity has been created to examine the behavior of the model while simulating different conditions. Conclusion This paper presents the modeling of the gear change process in a planetary gear using computers in the Matlab / Simulink environment. Computer-aided modeling of the gear change process enables the generation of different versions of virtual gear models with relevant data about their characteristics thus helping designers in their decision making in the iterative process of design, i. e. in making appropriate decisions in the early stages of design.

  4. Proactive Integration of Planetary Protection Needs Into Early Design Phases of Human Exploration Missions

    Science.gov (United States)

    Race, Margaret; Conley, Catharine

    Planetary protection (PP) policies established by the Committee on Space Research (COSPAR) of the International Council for Science have been in force effectively for five decades, ensuring responsible exploration and the integrity of science activities, for both human and robotic missions in the Solar System beyond low Earth orbit (LEO). At present, operations on most bodies in the solar system are not constrained by planetary protection considerations because they cannot be contaminated by Earth life in ways that impact future space exploration. However, operations on Mars, Europa, and Enceladus, which represent locations with biological potential, are subject to strict planetary protection constraints for missions of all types because they can potentially be contaminated by organisms brought from Earth. Forward contamination control for robotic missions is generally accomplished through a combination of activities that reduce the bioload of microbial hitchhikers on outbound spacecraft prior to launch. Back contamination control for recent robotic missions has chiefly been accomplished by selecting sample-return targets that have little or no potential for extant life (e.g., cometary particles returned by Stardust mission). In the post-Apollo era, no human missions have had to deal with planetary protection constraints because they have never left Earth orbit. Future human missions to Mars, for example, will experience many of the challenges faced by the Apollo lunar missions, with the added possibility that astronauts on Mars may encounter habitable environments in their exploration or activities. Current COSPAR PP Principles indicate that safeguarding the Earth from potential back contamination is the highest planetary protection priority in Mars exploration. While guidelines for planetary protection controls on human missions to Mars have been established by COSPAR, detailed engineering constraints and processes for implementation of these guidelines have not

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

    Science.gov (United States)

    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.

  6. Confronting unknown planetary boundary threats from chemical pollution.

    Science.gov (United States)

    Persson, Linn M; Breitholtz, Magnus; Cousins, Ian T; de Wit, Cynthia A; MacLeod, Matthew; McLachlan, Michael S

    2013-11-19

    Rockström et al. proposed a set of planetary boundaries that delimitate a "safe operating space for humanity". One of the planetary boundaries is determined by "chemical pollution", however no clear definition was provided. Here, we propose that there is no single chemical pollution planetary boundary, but rather that many planetary boundary issues governed by chemical pollution exist. We identify three conditions that must be simultaneously met for chemical pollution to pose a planetary boundary threat. We then discuss approaches to identify chemicals that could fulfill those conditions, and outline a proactive hazard identification strategy that considers long-range transport and the reversibility of chemical pollution. PMID:23980998

  7. Aerocapture Technology Development for Planetary Science - Update

    Science.gov (United States)

    Munk, Michelle M.

    2006-01-01

    Within NASA's Science Mission Directorate is a technological program dedicated to improving the cost, mass, and trip time of future scientific missions throughout the Solar System. The In-Space Propulsion Technology (ISPT) Program, established in 2001, is charged with advancing propulsion systems used in space from Technology Readiness Level (TRL) 3 to TRL6, and with planning activities leading to flight readiness. The program's content has changed considerably since inception, as the program has refocused its priorities. One of the technologies that has remained in the ISPT portfolio through these changes is Aerocapture. Aerocapture is the use of a planetary body's atmosphere to slow a vehicle from hyperbolic velocity to a low-energy orbit suitable for science. Prospective use of this technology has repeatedly shown huge mass savings for missions of interest in planetary exploration, at Titan, Neptune, Venus, and Mars. With launch vehicle costs rising, these savings could be the key to mission viability. This paper provides an update on the current state of the Aerocapture technology development effort, summarizes some recent key findings, and highlights hardware developments that are ready for application to Aerocapture vehicles and entry probes alike. Description of Investments: The Aerocapture technology area within the ISPT program has utilized the expertise around NASA to perform Phase A-level studies of future missions, to identify technology gaps that need to be filled to achieve flight readiness. A 2002 study of the Titan Explorer mission concept showed that the combination of Aerocapture and a Solar Electric Propulsion system could deliver a lander and orbiter to Titan in half the time and on a smaller, less expensive launch vehicle, compared to a mission using chemical propulsion for the interplanetary injection and orbit insertion. The study also identified no component technology breakthroughs necessary to implement Aerocapture on such a mission

  8. Body punk

    DEFF Research Database (Denmark)

    Mogensen, Kevin

    BODYPUNK - A Treatise on male body builders and the meaning of the body in the shadow of an Anti Doping Campaign Based on a qualitative study, the thesis investigates the visual representation of the male bodybuilder found in the national anti doping campaign: ‗ "The hunt has begun" along with an...... analysis of the embodied meaning of men‘s bodybuilding....

  9. Planetary Gearbox Fault Diagnosis Using Envelope Manifold Demodulation

    Directory of Open Access Journals (Sweden)

    Weigang Wen

    2016-01-01

    Full Text Available The important issue in planetary gear fault diagnosis is to extract the dependable fault characteristics from the noisy vibration signal of planetary gearbox. To address this critical problem, an envelope manifold demodulation method is proposed for planetary gear fault detection in the paper. This method combines complex wavelet, manifold learning, and frequency spectrogram to implement planetary gear fault characteristic extraction. The vibration signal of planetary gear is demodulated by wavelet enveloping. The envelope energy is adopted as an indicator to select meshing frequency band. Manifold learning is utilized to reduce the effect of noise within meshing frequency band. The fault characteristic frequency of the planetary gear is shown by spectrogram. The planetary gearbox model and test rig are established and experiments with planet gear faults are conducted for verification. All results of experiment analysis demonstrate its effectiveness and reliability.

  10. Body Weight and Body Image

    OpenAIRE

    McFarlane Traci; Olmsted Marion P

    2004-01-01

    Abstract Health Issue Body weight is of physical and psychological importance to Canadian women; it is associated with health status, physical activity, body image, and self-esteem. Although the problems associated with overweight and obesity are indeed serious, there are also problems connected to being underweight. Weight prejudice and the dieting industry intensify body image concerns for Canadian women and can have a major negative impact on self-esteem. Key Findings Women have lower BMIs...

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

    Science.gov (United States)

    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

  12. Mathematical optimization of matter distribution for a planetary system configuration

    Science.gov (United States)

    Morozov, Yegor; Bukhtoyarov, Mikhail

    2016-07-01

    Planetary formation is mostly a random process. When the humanity reaches the point when it can transform planetary systems for the purpose of interstellar life expansion, the optimal distribution of matter in a planetary system will determine its population and expansive potential. Maximization of the planetary system carrying capacity and its potential for the interstellar life expansion depends on planetary sizes, orbits, rotation, chemical composition and other vital parameters. The distribution of planetesimals to achieve maximal carrying capacity of the planets during their life cycle, and maximal potential to inhabit other planetary systems must be calculated comprehensively. Moving much material from one planetary system to another is uneconomic because of the high amounts of energy and time required. Terraforming of the particular planets before the whole planetary system is configured might drastically decrease the potential habitability the whole system. Thus a planetary system is the basic unit for calculations to sustain maximal overall population and expand further. The mathematical model of optimization of matter distribution for a planetary system configuration includes the input observed parameters: the map of material orbiting in the planetary system with specified orbits, masses, sizes, and the chemical compound for each, and the optimized output parameters. The optimized output parameters are sizes, masses, the number of planets, their chemical compound, and masses of the satellites required to make tidal forces. Also the magnetic fields and planetary rotations are crucial, but they will be considered in further versions of this model. The optimization criteria is the maximal carrying capacity plus maximal expansive potential of the planetary system. The maximal carrying capacity means the availability of essential life ingredients on the planetary surface, and the maximal expansive potential means availability of uranium and metals to build

  13. Dynamics of the Galactic Bulge using Planetary Nebulae

    CERN Document Server

    Beaulieu, S F; Kálnay, A J; Saha, P; Zhao, H S; Beaulieu, Sylvie F.; Freeman, Kenneth C.; Kalnajs, Agris J.; Saha, Prasenjit; Zhao, HongSheng

    2000-01-01

    Evidence for a bar at the center of the Milky Way triggered a renewed enthusiasm for dynamical modelling of the Galactic bar-bulge. Our goal is to compare the kinematics of a sample of tracers, planetary nebulae, widely distributed over the bulge with the corresponding kinematics for a range of models of the inner Galaxy. Three of these models are N-body barred systems arising from the instabilities of a stellar disk (Sellwood, Fux and Kalnajs), and one is a Schwarzschild system constructed to represent the 3D distribution of the COBE/DIRBE near-IR light and then evolved as an N-body system for a few dynamical times (Zhao). For the comparison of our data with the models, we use a new technique developed by Saha (1998). The procedure finds the parameters of each model, i.e. the solar galactocentric distance R_o in model units, the orientation angle phi, the velocity scale (in km/s per model unit), and the solar tangential velocity which best fit the data.

  14. Exploring New Phenomena in Salty Water Under Planetary Conditions

    Science.gov (United States)

    Goncharov, A. F.; Bove, L. E.; Klotz, S.; Gaal, R.; Saitta, A. M.; Gillet, P.

    2015-12-01

    Compressed water is overspread on Earth at depth and in the extra-terrestrial space, both interstellar and on outer planets and moons (ice bodies) [1]. Under the conditions experienced in these celestial bodies water displays an incredibly rich phase diagram, including sixteen known crystalline phases, three amorphous ones, and predicted exotic properties like plasticity [2], ionization [3], and superionicity [4]. In this talk I will review our recent experimental results on salty (LiCl, NaCl, MgCl2) water under extreme conditions including: plasticity [5], pressure-induced polyamorphism [6], salty ice crystallization under high pressure [7], and hydrogen bond symmetrisation at Mbar pressures [8]. [1] De Pater, I., and Lissauer, J.J. Planetary Sciences. Cambridge University Press (2004). [2] Wang, Y., Liu, H., et al. Nat. Comm. 563 1566 (2011).[3] Aragones, L., and Vega, C., J. Chem. Phys. 130, 244504 (2009).[4] Cavazzoni, C., et al., Science 283, 44-46 (1999).[5] Bove, L. E., Dreyfus, C. et al., JCP 139, 044501 (2013) ; Ruiz, G. N., Bove, L. E. et al., PCCP 16 18553-18562 (2014).[6] Bove, L. E., Klotz, S. et al., Phys. Rev. Lett. 106, 125701 (2011); Ludl, A. A., Bove, L. E. et al., PCCP 17, 14054 (2015). [7] Klotz, S., Bove, L. E. t al., Nat. Mat. 8, 405 (2009) ; Ludl A. A., Bove, L. E., submitted (2015).[8] Bove L. E. , Gaal, R. et al., PNAS 112, 27 (2015).

  15. Dynamical Friction and Resonance Trapping in Planetary Systems

    CERN Document Server

    Haghighipour, N

    1998-01-01

    A restricted planar circular three-body system, consisting of the Sun and two planets, is studied as a simple model for a planetary system. The mass of the inner planet is considered to be larger and the system is assumed to be moving in a uniform interplanetary medium with constant density. Numerical integrations of this system indicate a resonance capture when the dynamical friction of the interplanetary medium is taken into account. As a result of this resonance trapping, the ratio of orbital periods of the two planets becomes nearly commensurate and the eccentricity and semimajor axis of the orbit of the outer planet and also its angular momentum and total energy become constant. It appears from the numerical work that the resulting commensurability and also the resonant values of the orbital elements of the outer planet are essentially independent of the initial relative positions of the two bodies. The results of numerical integrations of this system are presented and the first-order partially averaged ...

  16. Planetary Systems and the Formation of Habitable Planets

    CERN Document Server

    Dvorak, Rudolf; Burger, Christoph; Schäfer, Christoph; Speith, Roland

    2015-01-01

    As part of a national scientific network 'Pathways to Habitability' the formation of planets and the delivery of water onto these planets is a key question as water is essential for the development of life. In the first part of the paper we summarize the state of the art of planet formation - which is still under debate in the astronomical community - before we show our results on this topic. The outcome of our numerical simulations depends a lot on the choice of the initial distribution of planetesimals and planetary embryos after gas disappeared in the protoplanetary disk. We also take into account that some of these planetesimals of sizes in the order of the mass of the Moon already contained water; the quantity depends on the distance from the Sun - close-by bodies are dry, but starting from a distance of about 2 AU they can contain substantial amounts of water. We assume that the gas giants and terrestrial planets are already formed when we check the collisions of the small bodies containing water (in th...

  17. Chondrule Formation via Impact Jetting Triggered by Planetary Accretion

    Science.gov (United States)

    Hasegawa, Yasuhiro; Wakita, Shigeru; Matsumoto, Yuji; Oshino, Shoichi

    2016-01-01

    Chondrules are one of the most primitive elements that can serve as a fundamental clue to the origin of our solar system. We investigate a formation scenario of chondrules that involves planetesimal collisions and the resultant impact jetting. Planetesimal collisions are the main agent to regulate planetary accretion that leads to the formation of terrestrial planets and cores of gas giants. The key component of this scenario is that ejected materials can melt when the impact velocity between colliding planetesimals exceeds about 2.5 km s-1. Previous simulations have shown that the process is efficient enough to reproduce the primordial abundance of chondrules. We examine this scenario carefully by performing semi-analytical calculations that are developed based on the results of direct N-body simulations. As found in the previous work, we confirm that planetesimal collisions that occur during planetary accretion can play an important role in forming chondrules. This arises because protoplanet-planetesimal collisions can achieve an impact velocity of about 2.5 km s-1 or higher, as protoplanets approach the isolation mass (Mp,iso). Assuming that the ejected mass is a fraction (Fch) of the colliding planetesimals’ mass, we show that the resultant abundance of chondrules is expressed well by FchMp,iso, as long as the formation of protoplanets is completed within a given disk lifetime. We perform a parameter study and examine how the abundance of chondrules and the timing of their formation change. We find that the impact jetting scenario generally works reasonably well for a certain range of parameters, while more dedicated work would be needed to include other physical processes that are neglected in this work and to examine their effects on chondrule formation.

  18. Mapping planetary caves with an autonomous, heterogeneous robot team

    Science.gov (United States)

    Husain, Ammar; Jones, Heather; Kannan, Balajee; Wong, Uland; Pimentel, Tiago; Tang, Sarah; Daftry, Shreyansh; Huber, Steven; Whittaker, William L.

    Caves on other planetary bodies offer sheltered habitat for future human explorers and numerous clues to a planet's past for scientists. While recent orbital imagery provides exciting new details about cave entrances on the Moon and Mars, the interiors of these caves are still unknown and not observable from orbit. Multi-robot teams offer unique solutions for exploration and modeling subsurface voids during precursor missions. Robot teams that are diverse in terms of size, mobility, sensing, and capability can provide great advantages, but this diversity, coupled with inherently distinct low-level behavior architectures, makes coordination a challenge. This paper presents a framework that consists of an autonomous frontier and capability-based task generator, a distributed market-based strategy for coordinating and allocating tasks to the different team members, and a communication paradigm for seamless interaction between the different robots in the system. Robots have different sensors, (in the representative robot team used for testing: 2D mapping sensors, 3D modeling sensors, or no exteroceptive sensors), and varying levels of mobility. Tasks are generated to explore, model, and take science samples. Based on an individual robot's capability and associated cost for executing a generated task, a robot is autonomously selected for task execution. The robots create coarse online maps and store collected data for high resolution offline modeling. The coordination approach has been field tested at a mock cave site with highly-unstructured natural terrain, as well as an outdoor patio area. Initial results are promising for applicability of the proposed multi-robot framework to exploration and modeling of planetary caves.

  19. LMC SMP 64 - The youngest planetary nebula?

    International Nuclear Information System (INIS)

    The planetary nebula SMP 64 in the Large Magellanic Cloud is shown to possess several properties which set it apart from the general PN population. These are an extremely high central electron density, a strong radial density gradient, and a central star with a very low effective temperature, T(eff) = 31,500 K. However, the luminosity of the central star is 6400 solar luminosities, implying a core mass of 0.62 solar mass, typical of the Magellanic Cloud population of planetary nebulae. It is concluded that the central star of SMP 64 has only just reached a temperature high enough to ionize a portion of the material ejected during the asymptotic giant branch evolution of the central star. 25 refs

  20. Planetary protection appraoch for ExoMars

    Science.gov (United States)

    Kminek, G.; Guarnieri, V.

    The scientific objective of the ExoMars mission is the search for life on Mars As a result of that the planetary protection category assigned to the mission is a modified category IVc The modification being that the requirements of category IVb apply along with the additional category IVc requirements As the discussion of what exactly defines a special region is still ongoing the detailed requirements for this category might have to be adjusted during phase B1 A dedicated six month subcontract released by the prime contractor in phase B1 will propose a programmatic and technical implementation of the appropriate planetary protection requirements for the ExoMars mission This contract includes a trade-off between sterile integration and terminal sterilization process proposed AIV AIT flow based on trade-off preliminary bioburden allocation proposed bioburden reduction processes disposal of cruise stage etc The preliminary result of this activity will be presented

  1. Heat conduction fronts in planetary nebulae

    Science.gov (United States)

    Soker, Noam

    1994-01-01

    We present arguments which suggest that many of the x-ray, some optical, and some UV observations of planetary nebulae, can be explained by the presence of heat conduction fronts. The heat flows from the hot bubble formed by the shocked fast wind to the cool shell and halo. Heat conduction fronts are likely to account for emission of x rays from plasma at lower temperature than the expected temperature of the hot bubble. In the presence of magnetic fields, only a small fraction of the fast wind luminosity emerges as radiation. Heat conduction fronts can naturally produce some unusual line flux ratios, which are observed in some planetary nebulae. Heat conduction fronts may heat the halo and cause some material at the inner surface of the shell to expand slower than the rest of the shell. In the presence of an asymmetrical magnetic field, this flow, the x-ray intensity, and the emission lines, may acquire asymmetrical structure as well.

  2. Lunar and Planetary Webcam User's Guide

    CERN Document Server

    Mobberley, Martin

    2006-01-01

    Inexpensive webcams are revolutionizing imaging in amateur astronomy by providing an affordable alternative to cooled-chip astronomical CCD cameras, for photographing the brighter astronomical objects. Webcams – costing only a few tens of dollars – are capable of more advanced high resolution work than "normal" digital cameras because their rapid image download speed can freeze fine planetary details, even through the Earth's turbulent atmosphere. Also, their simple construction makes it easy to remove the lens, allowing them to be used at high power at the projected focus of an astronomical telescope. Webcams also connect direct to a PC, so that software can be used to "stack" multiple images, providing a stunning increase in image quality. In the Lunar and Planetary Webcam User’s Guide Martin Mobberley de-mystifies the jargon of webcams and computer processing, and provides detailed hints and tips for imaging the Sun, Moon and planets with a webcam. He looks at each observing target separately, descri...

  3. Laser Mass Spectrometry in Planetary Science

    International Nuclear Information System (INIS)

    Knowing the chemical, elemental, and isotopic composition of planetary objects allows the study of their origin and evolution within the context of our solar system. Exploration plans in planetary research of several space agencies consider landing spacecraft for future missions. Although there have been successful landers in the past, more landers are foreseen for Mars and its moons, Venus, the jovian moons, and asteroids. Furthermore, a mass spectrometer on a landed spacecraft can assist in the sample selection in a sample-return mission and provide mineralogical context, or identify possible toxic soils on Mars for manned Mars exploration. Given the resources available on landed spacecraft mass spectrometers, as well as any other instrument, have to be highly miniaturised.

  4. Testing Lorentz symmetry with planetary orbital dynamics

    CERN Document Server

    Hees, Aurélien; Poncin-Lafitte, Christophe Le; Bourgoin, Adrien; Rivoldini, Attilio; Lamine, Brahim; Meynadier, Frédéric; Guerlin, Christine; Wolf, Peter

    2015-01-01

    Planetary ephemerides are a very powerful tool to constrain deviations from the theory of General Relativity using orbital dynamics. The effective field theory framework called the Standard-Model Extension (SME) has been developed in order to systematically parametrize hypothetical violations of Lorentz symmetry (in the Standard Model and in the gravitational sector). In this communication, we use the latest determinations of the supplementary advances of the perihelia and of the nodes obtained by planetary ephemerides analysis to constrain SME coefficients from the pure gravity sector and also from gravity-matter couplings. Our results do not show any deviation from GR and they improve current constraints. Moreover, combinations with existing constraints from Lunar Laser Ranging and from atom interferometry gravimetry allow us to disentangle contributions from the pure gravity sector from the gravity-matter couplings.

  5. Strategic approaches to planetary base development

    Science.gov (United States)

    Roberts, Barney B.

    1992-01-01

    The evolutionary development of a planetary expansionary outpost is considered in the light of both technical and economic issues. The outline of a partnering taxonomy is set forth which encompasses both institutional and temporal issues related to establishing shared interests and investments. The purely technical issues are discussed in terms of the program components which include nonaerospace technologies such as construction engineering. Five models are proposed in which partnership and autonomy for participants are approached in different ways including: (1) the standard customer/provider relationship; (2) a service-provider scenario; (3) the joint venture; (4) a technology joint-development model; and (5) a redundancy model for reduced costs. Based on the assumed characteristics of planetary surface systems the cooperative private/public models are championed with coordinated design by NASA to facilitate outside cooperation.

  6. Exploring the planetary boundary for chemical pollution

    DEFF Research Database (Denmark)

    Diamond, Miriam L.; de Wit, Cynthia A.; Molander, Sverker;

    2015-01-01

    Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if "unacceptable global change" is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of...... ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales...... evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step...

  7. Earth-like Habitats in Planetary Systems

    CERN Document Server

    Fritz, Jörg; Kührt, Ekkehard; Morbidelli, Alessandro; Tornow, Carmen; Wünnemann, Kai; Fernandes, Vera A; Grenfell, Lee J; Rauer, Heike; Wagner, Roland; Werner, Stephanie C

    2014-01-01

    Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the planetary system as a whole governs a particular planet's claim on habitability. Here we focus on such systemic aspects and discuss their relevance to the formation of an 'Earth-like' habitable planet. We summarize our results obtained by lunar sample work and numerical models within the framework of the Research Alliance "Planetary Evolution and Life". We consider various scenarios which simulate the dynamical evolution of the Solar System and discuss the likelihood of forming an Earth-like world orbiting another star. Our model approach is constrained by observations of the modern Solar System and the knowledge of its history. Results suggest that the long-term presence of terrestrial planets is jeopardized due to gravitational interactions if giant planets are present. But habitability of inner rocky planets may be supported in th...

  8. Aerocapture Inflatable Decelerator for Planetary Entry

    Science.gov (United States)

    Reza, Sajjad; Hund, Richard; Kustas, Frank; Willcockson, William; Songer, Jarvis; Brown, Glen

    2007-01-01

    Forward Attached Inflatable Decelerators, more commonly known as inflatable aeroshells, provide an effective, cost efficient means of decelerating spacecrafts by using atmospheric drag for aerocapture or planetary entry instead of conventional liquid propulsion deceleration systems. Entry into planetary atmospheres results in significant heating and aerodynamic pressures which stress aeroshell systems to their useful limits. Incorporation of lightweight inflatable decelerator surfaces with increased surface-area footprints provides the opportunity to reduce heat flux and induced temperatures, while increasing the payload mass fraction. Furthermore, inflatable aeroshell decelerators provide the needed deceleration at considerably higher altitudes and Mach numbers when compared with conventional rigid aeroshell entry systems. Inflatable aeroshells also provide for stowage in a compact space, with subsequent deployment of a large-area, lightweight heatshield to survive entry heating. Use of a deployable heatshield decelerator enables an increase in the spacecraft payload mass fraction and may eliminate the need for a spacecraft backshell.

  9. Instrumentation development for planetary in situ 40Ar/39Ar geochronology

    Science.gov (United States)

    Davidheiser-Kroll, B.; Morgan, L. E.; Munk, M.; Warner, N. H.; Gupta, S.; Slaybaugh, R.; Harkness, P.; Mark, D. F.

    2015-12-01

    The chronology of the Solar System, particularly the timing of formation of extraterrestrial bodies and their features, is a major outstanding problem in planetary science. Although various chronological methods for in situ geochronology have been proposed (e.g. Rb-Sr, K-Ar), and even applied (K-Ar, Farley et al., 2014), the reliability, accuracy, and applicability of the 40Ar/39Ar method makes it by far the most desirable chronometer for dating extraterrestrial bodies. The method however relies on the neutron irradiation of samples, and thus a neutron source. We will discuss the challenges and feasibility of deploying a passive neutron source to planetary surfaces for the in situ application of the 40Ar/39Ar chronometer. Requirements in generating and shielding neutrons, as well as analyzing samples are discussed, along with an exploration of limitations such as mass, power, and cost. Two potential solutions for the in situ extraterrestrial deployment of the 40Ar/39Ar method will be presented. Although this represents a challenging task, developing the technology to apply the 40Ar/39Ar method on planetary surfaces would represent a major advance towards constraining the timescale of solar system formation and evolution.

  10. Dynamics of the 3/1 planetary mean-motion resonance. An application to the HD60532 b-c planetary system

    CERN Document Server

    Alves, A J; Santos, M Tadeu dos

    2015-01-01

    In this paper, we use a semi-analytical approach to analyze the global structure of the phase space of the planar planetary 3/1 mean-motion resonance, in cases where the outer planet is more massive than its inner companion. We show that the resonant dynamics can be described using only two fundamental parameters, the total angular momentum and the scaling parameter. The topology of the Hamiltonian function describing the resonant behaviour is studied on the representative planes that allows us to investigate a large domain of the phase space of the three-body problem without time-expensive numerical integrations of the equations of motion, and without any restriction on the magnitude of the planetary eccentricities. The families of the well known Apsidal Corotation Resonances (ACR) parameterized by the planetary mass ratio are obtained and their stability is analyzed. The main dynamical features in the domains around ACR are also investigated in detail by means of spectral analysis techniques, which allow us...

  11. Planetary Protection for LIFE-Sample Return from Enceladus

    Science.gov (United States)

    Tsou, Peter; Yano, Hajime; Takano, Yoshinori; McKay, David; Takai, Ken; Anbar, Ariel; Baross, J.

    Introduction: We are seeking a balanced approach to returning Enceladus plume samples to state-of-the-art terrestrial laboratories to search for signs of life. NASA, ESA, JAXA and other space agencies are seeking habitable worlds and life beyond Earth. Enceladus, an icy moon of Saturn, is the first known body in the Solar System besides Earth to emit liquid water from its interior. Enceladus is the most accessible body in our Solar System for a low cost flyby sample return mission to capture aqueous based samples, to determine its state of life development, and shed light on how life can originate on wet planets/moons. LIFE combines the unique capabilities of teams of international exploration expertise. These returned Enceladus plume samples will determine if this habitable body is in fact inhabited [McKay et al, 2014]. This paper describes an approach for the LIFE mission to capture and return samples from Enceladus while meeting NASA and COSPAR planetary protection requirements. Forward planetary protection requirements for spacecraft missions to icy solar system bodies have been defined, however planetary protection requirements specific to an Earth return of samples collected from Enceladus or other Outer Planet Icy Moons, have yet to be defined. Background: From the first half century of space exploration, we have returned samples only from the Moon, comet Wild 2, the Solar Wind and the asteroid Itokawa. The in-depth analyses of these samples in terrestrial laboratories have yielded detailed chemical information that could not have been obtained otherwise. While obtaining samples from Solar System bodies is trans-formative science, it is rarely performed due to cost and complexity. The discovery by Cassini of geysers on Enceladus and organic materials in the ejected plume indicates that there is an exceptional opportunity and strong scientific rationale for LIFE. The earliest low-cost possible flight opportunity is the next Discovery Mission [Tsou et al 2012

  12. Finite-Dimensional Turbulence of Planetary Waves

    OpenAIRE

    2009-01-01

    Finite-dimensional wave turbulence refers to the chaotic dynamics of interacting wave `clusters' consisting of finite number of connected wave triads with exact three-wave resonances. We examine this phenomenon using the example of atmospheric planetary (Rossby) waves. It is shown that the dynamics of the clusters is determined by the types of connections between neighboring triads within a cluster; these correspond to substantially different scenarios of energy flux between different triads....

  13. Quantitative modeling of planetary magnetospheric magnetic fields

    Science.gov (United States)

    Walker, R. J.

    1979-01-01

    Three new quantitative models of the earth's magnetospheric magnetic field have recently been presented: the Olson-Pfitzer model, the Tsyganenko model, and the Voigt model. The paper reviews these models in some detail with emphasis on the extent to which they have succeeded in improving on earlier models. The models are compared with the observed field in both magnitude and direction. Finally, the application to other planetary magnetospheres of the techniques used to model the earth's magnetospheric magnetic field is briefly discussed.

  14. ANALYSIS METHOD OF AUTOMATIC PLANETARY TRANSMISSION KINEMATICS

    OpenAIRE

    Józef DREWNIAK; Stanisław ZAWIŚLAK; Wieczorek, Andrzej

    2014-01-01

    In the present paper, planetary automatic transmission is modeled by means of contour graphs. The goals of modeling could be versatile: ratio calculating via algorithmic equation generation, analysis of velocity and accelerations. The exemplary gears running are analyzed, several drives/gears are consecutively taken into account discussing functional schemes, assigned contour graphs and generated system of equations and their solutions. The advantages of the method are: algorithmic approach, ...

  15. Planetary nebulae abundances and stellar evolution

    OpenAIRE

    Pottasch, S. R.; Bernard-Salas, J.

    2006-01-01

    A summary is given of planetary nebulae abundances from ISO measurements. It is shown that these nebulae show abundance gradients (with galactocentric distance), which in the case of neon, argon, sulfur and oxygen (with four exceptions) are the same as HII regions and early type star abundance gradients. The abundance of these elements predicted from these gradients at the distance of the Sun from the center are exactly the solar abundance. Sulfur is the exception to this; the reason for this...

  16. Planetary tides during the Maunder sunspot minimum

    International Nuclear Information System (INIS)

    Sun-centered planetary conjunctions and tidal potentials are here constructed for the AD1645 to 1715 period of sunspot absence, referred to as the 'Maunder Minimum'. These are found to be effectively indistinguishable from patterns of conjunctions and power spectra of tidal potential in the present era of a well established 11 year sunspot cycle. This places a new and difficult restraint on any tidal theory of sunspot formation. Problems arise in any direct gravitational theory due to the apparently insufficient forces and tidal heights involved. Proponents of the tidal hypothesis usually revert to trigger mechanisms, which are difficult to criticise or test by observation. Any tidal theory rests on the evidence of continued sunspot periodicity and the substantiation of a prolonged period of solar anomaly in the historical past. The 'Maunder Minimum' was the most drastic change in the behaviour of solar activity in the last 300 years; sunspots virtually disappeared for a 70 year period and the 11 year cycle was probably absent. During that time, however, the nine planets were all in their orbits, and planetary conjunctions and tidal potentials were indistinguishable from those of the present era, in which the 11 year cycle is well established. This provides good evidence against the tidal theory. The pattern of planetary tidal forces during the Maunder Minimum was reconstructed to investigate the possibility that the multiple planet forces somehow fortuitously cancelled at the time, that is that the positions of the slower moving planets in the 17th and early 18th centuries were such that conjunctions and tidal potentials were at the time reduced in number and force. There was no striking dissimilarity between the time of the Maunder Minimum and any period investigated. The failure of planetary conjunction patterns to reflect the drastic drop in sunspots during the Maunder Minimum casts doubt on the tidal theory of solar activity, but a more quantitative test

  17. Dynamical Habitability of Known Extrasolar Planetary Systems

    OpenAIRE

    Menou, Kristen; Tabachnik, Serge

    2002-01-01

    Habitability is usually defined as the requirement for a terrestrial planet's atmosphere to sustain liquid water. This definition can be complemented by the dynamical requirement that other planets in the system do not gravitationally perturb terrestrial planets outside of their habitable zone, the orbital region allowing the existence of liquid water. We quantify the dynamical habitability of 85 known extrasolar planetary systems via simulations of their orbital dynamics in the presence of p...

  18. Planetary nebulae in the Small Magellanic Cloud

    Science.gov (United States)

    Ventura, P.; Stanghellini, L.; Di Criscienzo, M.; García-Hernández, D. A.; Dell'Agli, F.

    2016-08-01

    We analyse the planetary nebulae (PNe) population of the Small Magellanic Cloud (SMC), based on evolutionary models of stars with metallicities in the range 10-3 ≤ Z ≤ 4 × 10-3 and mass 0.9 M⊙ Cloud is explained on the basis of the diverse star formation history and age-metallicity relation of the two galaxies. The implications of this study for some still highly debated points regarding the AGB evolution are also commented.

  19. Debris disc formation induced by planetary growth

    OpenAIRE

    Kobayashi, Hiroshi; Loehne, Torsten

    2014-01-01

    Several hundred stars older than 10 million years have been observed to have infrared excesses. These observations are explained by dust grains formed by the collisional fragmentation of hidden planetesimals. Such dusty planetesimal discs are known as debris discs. In a dynamically cold planetesimal disc, collisional coagulation of planetesimals produces planetary embryos which then stir the surrounding leftover planetesimals. Thus, the collisional fragmentation of planetesimals that results ...

  20. Free and Open Source Software for Geospatial in the field of planetary science

    Science.gov (United States)

    Frigeri, A.

    2012-12-01

    Information technology applied to geospatial analyses has spread quickly in the last ten years. The availability of OpenData and data from collaborative mapping projects increased the interest on tools, procedures and methods to handle spatially-related information. Free Open Source Software projects devoted to geospatial data handling are gaining a good success as the use of interoperable formats and protocols allow the user to choose what pipeline of tools and libraries is needed to solve a particular task, adapting the software scene to his specific problem. In particular, the Free Open Source model of development mimics the scientific method very well, and researchers should be naturally encouraged to take part to the development process of these software projects, as this represent a very agile way to interact among several institutions. When it comes to planetary sciences, geospatial Free Open Source Software is gaining a key role in projects that commonly involve different subjects in an international scenario. Very popular software suites for processing scientific mission data (for example, ISIS) and for navigation/planning (SPICE) are being distributed along with the source code and the interaction between user and developer is often very strict, creating a continuum between these two figures. A very widely spread library for handling geospatial data (GDAL) has started to support planetary data from the Planetary Data System, and recent contributions enabled the support to other popular data formats used in planetary science, as the Vicar one. The use of Geographic Information System in planetary science is now diffused, and Free Open Source GIS, open GIS formats and network protocols allow to extend existing tools and methods developed to solve Earth based problems, also to the case of the study of solar system bodies. A day in the working life of a researcher using Free Open Source Software for geospatial will be presented, as well as benefits and

  1. Planetary protection for Europa radar sounder antenna

    Science.gov (United States)

    Aaron, Kim M.; Moussessian, Alina; Newlin, Laura E.; Willis, Paul B.; Chen, Fei; Harcke, Leif J.; Chapin, Elaine; Jun, Insoo; Gim, Yonggyu; McEachen, Michael; Allen, Scotty; Kirchner, Donald; Blankenship, Donald

    2016-05-01

    The potential for habitability puts stringent requirements on planetary protection for a mission to Europa. A long-wavelength radar sounder with a large antenna is one of the proposed instruments for a future Europa mission. The size and construction of radar sounding antennas make the usual methods of meeting planetary protection requirements challenging. This paper discusses a viable planetary protection scheme for an antenna optimized for Europa radar sounding. The preferred methodology for this antenna is exposure to 100 kGy (10 Mrad) in water of gamma radiation using a Cobalt-60 source for both bulk and surface sterilization and exposure to vapor hydrogen peroxide for surface treatment for possible recontamination due to subsequent handling. For the boom-supported antenna design, selected tests were performed to confirm the suitability of these treatment methods. A portion of a coilable boom residual from an earlier mission was irradiated and its deployment repeatability confirmed with no degradation. Elasticity was measured of several fiberglass samples using a four-point bending test to confirm that there was no degradation due to radiation exposure. Vapor hydrogen peroxide treatment was applied to the silver-coated braid used as the antenna radiating element as it was the material most likely to be susceptible to oxidative attack under the treatment conditions. There was no discernable effect. These tests confirm that the radar sounding antenna for a Europa mission should be able tolerate the proposed sterilization methods.

  2. Intelligent robots for planetary exploration and construction

    Science.gov (United States)

    Albus, James S.

    1992-02-01

    Robots capable of practical applications in planetary exploration and construction will require realtime sensory-interactive goal-directed control systems. A reference model architecture based on the NIST Real-time Control System (RCS) for real-time intelligent control systems is suggested. RCS partitions the control problem into four basic elements: behavior generation (or task decomposition), world modeling, sensory processing, and value judgment. It clusters these elements into computational nodes that have responsibility for specific subsystems, and arranges these nodes in hierarchical layers such that each layer has characteristic functionality and timing. Planetary exploration robots should have mobility systems that can safely maneuver over rough surfaces at high speeds. Walking machines and wheeled vehicles with dynamic suspensions are candidates. The technology of sensing and sensory processing has progressed to the point where real-time autonomous path planning and obstacle avoidance behavior is feasible. Map-based navigation systems will support long-range mobility goals and plans. Planetary construction robots must have high strength-to-weight ratios for lifting and positioning tools and materials in six degrees-of-freedom over large working volumes. A new generation of cable-suspended Stewart platform devices and inflatable structures are suggested for lifting and positioning materials and structures, as well as for excavation, grading, and manipulating a variety of tools and construction machinery.

  3. Interstellar and Planetary Analogs in the Laboratory

    Science.gov (United States)

    Salama, Farid

    2013-01-01

    We present and discuss the unique capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to investigate the interaction of ionizing radiation (UV, charged particles) with molecular species (neutral molecules, radicals and ions) and carbonaceous grains in the Solar System and in the Interstellar Medium (ISM). COSmIC stands for Cosmic Simulation Chamber, a laboratory chamber where interstellar and planetary analogs are generated, processed and analyzed. It is composed of a pulsed discharge nozzle (PDN) expansion that generates a free jet supersonic expansion in a plasma cavity coupled to two ultrahigh-sensitivity, complementary in situ diagnostics: a cavity ring down spectroscopy (CRDS) system for photonic detection and a Reflectron time-of-flight mass spectrometer (ReTOF-MS) for mass detection. This setup allows the study of molecules, ions and solids under the low temperature and high vacuum conditions that are required to simulate some interstellar, circumstellar and planetary physical environments providing new fundamental insights on the molecular level into the processes that are critical to the chemistry in the ISM, circumstellar and planet forming regions, and on icy objects in the Solar System. Recent laboratory results that were obtained using COSmIC will be discussed, in particular the progress that have been achieved in monitoring in the laboratory the formation of solid particles from their gas-phase molecular precursors in environments as varied as circumstellar outflow and planetary atmospheres.

  4. Russian Planetary Exploration History, Development, Legacy, Prospects

    CERN Document Server

    Harvey, Brian

    2007-01-01

    Russia’s accomplishments in planetary space exploration were not achieved easily. Formerly, the USSR experienced frustration in trying to tame unreliable Molniya and Proton upper stages and in tracking spacecraft over long distances. This book will assess the scientific haul of data from the Venus and Mars missions and look at the engineering approaches. The USSR developed several generations of planetary probes: from MV and Zond to the Phobos type. The engineering techniques used and the science packages are examined, as well as the nature of the difficulties encountered which ruined several missions. The programme’s scientific and engineering legacy is also addressed, as well as its role within the Soviet space programme as a whole. Brian Harvey concludes by looking forward to future Russian planetary exploration (e.g Phobos Grunt sample return mission). Several plans have been considered and may, with a restoration of funding, come to fruition. Soviet studies of deep space and Mars missions (e.g. TMK, ...

  5. Resonant Removal of Exomoons during Planetary Migration

    Science.gov (United States)

    Spalding, Christopher; Batygin, Konstantin; Adams, Fred C.

    2016-01-01

    Jupiter and Saturn play host to an impressive array of satellites, making it reasonable to suspect that similar systems of moons might exist around giant extrasolar planets. Furthermore, a significant population of such planets is known to reside at distances of several Astronomical Units (AU), leading to speculation that some moons thereof might support liquid water on their surfaces. However, giant planets are thought to undergo inward migration within their natal protoplanetary disks, suggesting that gas giants currently occupying their host star’s habitable zone formed farther out. Here we show that when a moon-hosting planet undergoes inward migration, dynamical interactions may naturally destroy the moon through capture into a so-called evection resonance. Within this resonance, the lunar orbit’s eccentricity grows until the moon eventually collides with the planet. Our work suggests that moons orbiting within about ∼10 planetary radii are susceptible to this mechanism, with the exact number dependent on the planetary mass, oblateness, and physical size. Whether moons survive or not is critically related to where the planet began its inward migration, as well as the character of interlunar perturbations. For example, a Jupiter-like planet currently residing at 1 AU could lose moons if it formed beyond ∼5 AU. Cumulatively, we suggest that an observational census of exomoons could potentially inform us on the extent of inward planetary migration, for which no reliable observational proxy currently exists.

  6. Mean Motion Resonances in Extrasolar Planetary Systems with Turbulence, Interactions, and Damping

    CERN Document Server

    Lecoanet, Daniel; Bloch, Anthony M; 10.1088/0004-637X/692/1/659

    2009-01-01

    This paper continues previous work on the effects of turbulence on mean motion resonances in extrasolar planetary systems. Turbulence is expected to arise in the disks that form planets, and these fluctuations act to compromise resonant configurations. This paper extends previous work by considering how interactions between the planets and possible damping effects imposed by the disk affect the outcomes. These physical processes are studied using three approaches: numerical integrations of the 3-body problem with additional forcing due to turbulence, model equations that reduce the problem to stochastically driven oscillators, and Fokker-Planck equations that describe the time evolution of an ensemble of systems. With this combined approach, we elucidate the physics of how turbulence can remove extrasolar planetary systems from mean motion resonance. As expected, systems with sufficiently large damping (dissipation) can maintain resonance, in spite of turbulent forcing. In the absence of strong damping, ensem...

  7. Body lice

    Science.gov (United States)

    Lice - body; Pediculosis corporis; Vagabond disease ... Diaz JH. Lice (pediculosis). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases . 8th ...

  8. Bog bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2015-01-01

    the bog bodies have been studied using medical and natural scientific methods, and recently many bog bodies have been re-examined using especially modern, medical imaging techniques. Because of the preservation of soft tissue, especially the skin, it has been possible to determine lesions and trauma......In northern Europe during the Iron Age, many corpses were deposited in bogs. The cold, wet and anaerobic environment leads in many cases to the preservation of soft tissues, so that the bodies, when found and excavated several thousand years later, are remarkably intact. Since the 19th century....... Conversely, the preservation of bones is less good, as the mineral component has been leached out by the acidic bog. Together with water-logging of collagenous tissue, this means that if the bog body is simply left to dry out when found, as was the case pre-19th century, the bones may literally warp...

  9. The evolution of planetary nebulae VII. Modelling planetary nebulae of distant stellar systems

    CERN Document Server

    Schönberner, D; Sandin, C; Steffen, M

    2010-01-01

    By means of hydrodynamical models we do the first investigations of how the properties of planetary nebulae are affected by their metal content and what can be learned from spatially unresolved spectrograms of planetary nebulae in distant stellar systems. We computed a new series of 1D radiation-hydrodynamics planetary nebulae model sequences with central stars of 0.595 M_sun surrounded by initial envelope structures that differ only by their metal content. At selected phases along the evolutionary path, the hydrodynamic terms were switched off, allowing the models to relax for fixed radial structure and radiation field into their equilibrium state with respect to energy and ionisation. The analyses of the line spectra emitted from both the dynamical and static models enabled us to systematically study the influence of hydrodynamics as a function of metallicity and evolution. We also recomputed selected sequences already used in previous publications, but now with different metal abundances. These sequences w...

  10. The stable Cr isotopic compositions of chondrites and silicate planetary reservoirs

    Science.gov (United States)

    Schoenberg, Ronny; Merdian, Alexandra; Holmden, Chris; Kleinhanns, Ilka C.; Haßler, Kathrin; Wille, Martin; Reitter, Elmar

    2016-06-01

    The depletion of chromium in Earth's mantle (∼2700 ppm) in comparison to chondrites (∼4400 ppm) indicates significant incorporation of chromium into the core during our planet's metal-silicate differentiation, assuming that there was no significant escape of the moderately volatile element chromium during the accretionary phase of Earth. Stable Cr isotope compositions - expressed as the ‰-difference in 53Cr/52Cr from the terrestrial reference material SRM979 (δ53/52CrSRM979 values) - of planetary silicate reservoirs might thus yield information about the conditions of planetary metal segregation processes when compared to chondrites. The stable Cr isotopic compositions of 7 carbonaceous chondrites, 11 ordinary chondrites, 5 HED achondrites and 2 martian meteorites determined by a double spike MC-ICP-MS method are within uncertainties indistinguishable from each other and from the previously determined δ53/52CrSRM979 value of -0.124 ± 0.101‰ for the igneous silicate Earth. Extensive quality tests support the accuracy of the stable Cr isotope determinations of various meteorites and terrestrial silicates reported here. The uniformity in stable Cr isotope compositions of samples from planetary silicate mantles and undifferentiated meteorites indicates that metal-silicate differentiation of Earth, Mars and the HED parent body did not cause measurable stable Cr isotope fractionation between these two reservoirs. Our results also imply that the accretionary disc, at least in the inner solar system, was homogeneous in its stable Cr isotopic composition and that potential volatility loss of chromium during accretion of the terrestrial planets was not accompanied by measurable stable isotopic fractionation. Small but reproducible variations in δ53/52CrSRM979 values of terrestrial magmatic rocks point to natural stable Cr isotope variations within Earth's silicate reservoirs. Further and more detailed studies are required to investigate whether silicate

  11. Development of Training Programs to Optimize Planetary Ambulation

    Science.gov (United States)

    Bloomberg, J. J.; Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Miller, C. A.; Brady, R.; Warren, L. E.; Rutley, T. M.; Kozlovskaya, I. B.

    2007-01-01

    Astronauts experience disturbances in functional mobility following their return to Earth due to adaptive responses that occur during exposure to the microgravity conditions of space flight. Despite significant time spent performing in-flight exercise routines, these training programs have not been able to mitigate postflight alterations in postural and locomotor function. Therefore, the goal of our two inter-related projects (NSBRI-ground based and ISS flight study, "Mobility") is to develop and test gait training programs that will serve to optimize functional mobility during the adaptation period immediately following space flight, thereby improving the safety and efficiency of planetary ambulation. The gait training program entails manipulating the sensory conditions of treadmill exercise to systematically challenge the balance and gait control system. This enhances the overall adaptability of locomotor function enabling rapid reorganization of gait control to respond to ambulation in different gravitational environments. To develop the training program, we are conducting a series of ground-based studies evaluating the training efficacy associated with variation in visual flow, body loading, and support surface stability during treadmill walking. We will also determine the optimal method to present training stimuli within and across training sessions to maximize both the efficacy and efficiency of the training procedure. Results indicate that variations in both visual flow and body unloading during treadmill walking leads to modification in locomotor control and can be used as effective training modalities. Additionally, the composition and timing of sensory challenges experienced during each training session has significant impact on the ability to rapidly reorganize locomotor function when exposed to a novel sensory environment. We have developed the capability of producing support surface variation during gait training by mounting a treadmill on a six

  12. The Planetary Data System - A solution to data management for the planetary science community

    Science.gov (United States)

    Dobinson, Elaine R.

    1990-01-01

    An overview of the first release of the Planetary Data System (PDS) is presented, and some of the challenges encountered during development of the system are described. The principal goals of the PDS are to distribute planetary science data and information about these data to NASA, to provide scientific knowledge to users of these data, and to provide for permanent storage. The current architecture and capabilities of the PDS (Version 1.0) are examined, and some of the special challenges encountered and lessons learned during the application are highlighted. Finally, implications for future versions of the PDS as well as for other science data systems are discussed.

  13. SPICE as an IAU Recommendation for Planetary Ephemerides

    Science.gov (United States)

    Acton, Charles; Bachman, Nathaniel; Folkner, William M.; Hilton, James

    2015-08-01

    In 2010 the IAU Commission 4 Working Group (WG) on Standardizing Access to Ephemerides and File Format Specification was formed to define a portable standard for planetary ephemeris files. The standard would have to work for all three sources of ephemerides-NASA/JPL, Institut de mécanique céleste de calcul des éphémérides (IMCCE), and Institute of Applied Astronomy (IAA). The WG decided to base its standard on the existing "SPICE"* Spacecraft/Planet kernel (SPK) format.The SPK format was created for use with the "SPICE" information system, used by many scientists and engineers worldwide to compute the geometry needed to plan and analyze data from robotic missions. SPICE is comprised of both data files and associated software, all freely available. SPICE data files, usually referred to as "kernels," provide ephemerides and size, shape and orientation of solar system bodies; spacecraft trajectory and orientation; reference frame specifications and implementations; instrument field-of-view geometry; and time system conversion data.Standard SPICE ephemeris files use the TDB time system-the WG requested SPICE be extended to accommodate ephemerides based on the TCB time system. Extensions were also needed to accommodate the IAA ephemeris representation as well as the integrated difference between coordinate time and proper time in the form of TT-TDB and TCG-TCB.Software to read the SPK kernels defined to accommodate planetary ephemerides is available in the SPICE toolkit, and also in stand-alone kernel readers available from IMCEE and IAA.SPK is also used within the SPICE community for natural satellites, asteroids, and comets. Future IAU discussions might lead to an expansion of the work done for planets to provide more general standards for these bodies.Portions of the research described in this publication was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration

  14. Planetary rovers robotic exploration of the solar system

    CERN Document Server

    Ellery, Alex

    2016-01-01

    The increasing adoption of terrain mobility – planetary rovers – for the investigation of planetary surfaces emphasises their central importance in space exploration. This imposes a completely new set of technologies and methodologies to the design of such spacecraft – and planetary rovers are indeed, first and foremost, spacecraft. This introduces vehicle engineering, mechatronics, robotics, artificial intelligence and associated technologies to the spacecraft engineer’s repertoire of skills. Planetary Rovers is the only book that comprehensively covers these aspects of planetary rover engineering and more. The book: • discusses relevant planetary environments to rover missions, stressing the Moon and Mars; • includes a brief survey of previous rover missions; • covers rover mobility, traction and control systems; • stresses the importance of robotic vision in rovers for both navigation and science; • comprehensively covers autonomous navigation, path planning and multi-rover formations on ...

  15. Planetary Science Research Discoveries (PSRD) www.psrd.hawaii.edu

    Science.gov (United States)

    Martel, L.; Taylor, J.

    2010-12-01

    NASA's Year of the Solar System is celebrating not only Solar System mission milestones but also the collective data reduction and analysis that happens here on Earth. The Cosmochemistry Program of NASA's Science Mission Directorate takes a direct approach to enhance student learning and engage the public in the latest research on meteorites, asteroids, planets, moons, and other materials in our Solar System with the website known as PSRD. The Planetary Science Research Discoveries (PSRD) website at www.psrd.hawaii.edu explores the science questions that researchers are actively pursuing about our Solar System and explains how the answers are discovered and what they mean. The site helps to convey the scientific basis for sample study to the broader scientific community and the excitement of new results in cosmochemistry to the general public. We share with our broad audience the fascinating discoveries made by cosmochemists, increasing public awareness of the value of sample-focused research in particular and of fundamental scientific research and space exploration in general. The scope of the website covers the full range of cosmochemical research and highlights the investigations of extraterrestrial materials that are used to better understand the origin of the Solar System and the processes by which planets, moons, and small bodies evolve. We relate the research to broader planetary science themes and mission results. Articles are categorized into: asteroids, comets, Earth, instruments of cosmochemistry, Jupiter system, Mars, Mars life issues, Mercury, meteorites, Moon, origins, and space weathering. PSRD articles are based on peer-reviewed, journal publications. Some PSRD articles are based on more than one published paper in order to present multiple views and outcomes of research on a topic of interest. To date, 150 PSRD articles have been based on 184 journal articles (and counting) written by some of the most active cosmochemists and planetary scientists

  16. Feasibility study of an automatic vehicle for planetary exploration

    Science.gov (United States)

    Gerli, C.; Murolo, A.; Mugnuolo, R.; Gallo, E.; Cantatore, F.; Giardino, L.

    1993-01-01

    A study with the following objectives is reported: definition of the scientific objectives of a planetary exploration using a rover; definition of the planetary rover requirements; identification and characterization of the main subsystems of the rover; definition and critical areas and technological risks; and verification of the possibility on international cooperation on a planetary mission. The use of such a rover to investigate the Moon and Mars is focused upon.

  17. Finite Element Residual Stress Analysis of Planetary Gear Tooth

    OpenAIRE

    Jungang Wang; Yong Wang; Zhipu Huo

    2013-01-01

    A method to simulate residual stress field of planetary gear is proposed. In this method, the finite element model of planetary gear is established and divided to tooth zone and profile zone, whose different temperature field is set. The gear’s residual stress simulation is realized by the thermal compression stress generated by the temperature difference. Based on the simulation, the finite element model of planetary gear train is established, the dynamic meshing process is simulated, and in...

  18. The International Planetary Data Alliance (IPDA)

    Science.gov (United States)

    Stein, Thomas; Gopala Krishna, Barla; Crichton, Daniel J.

    2016-07-01

    The International Planetary Data Alliance (IPDA) is a close association of partners with the aim of improving the quality of planetary science data and services to the end users of space based instrumentation. The specific mission of the IPDA is to facilitate global access to, and exchange of, high quality scientific data products managed across international boundaries. Ensuring proper capture, accessibility and availability of the data is the task of the individual member space agencies. The IPDA is focused on developing an international standard that allows discovery, query, access, and usage of such data across international planetary data archive systems. While trends in other areas of space science are concentrating on the sharing of science data from diverse standards and collection methods, the IPDA concentrates on promoting governing data standards that drive common methods for collecting and describing planetary science data across the international community. This approach better supports the long term goal of easing data sharing across system and agency boundaries. An initial starting point for developing such a standard will be internationalization of NASA's Planetary Data System's (PDS) PDS4 standard. The IPDA was formed in 2006 with the purpose of adopting standards and developing collaborations across agencies to ensure data is captured in common formats. It has grown to a dozen member agencies represented by a number of different groups through the IPDA Steering Committee. Member agencies include: Armenian Astronomical Society, China National Space Agency (CNSA), European Space Agency (ESA), German Aerospace Center (DLR), Indian Space Research Organization (ISRO), Italian Space Agency (ASI), Japanese Aerospace Exploration Agency (JAXA), National Air and Space Administration (NASA), National Centre for Space Studies (CNES), Space Research Institute (IKI), UAE Space Agency, and UK Space Agency. The IPDA Steering Committee oversees the execution of

  19. Signifying Bodies

    DEFF Research Database (Denmark)

     In our everyday lives we strive to stay healthy and happy, while we live as our selves, engage with each other, and discover an infinite world of possibilities. Health arises and diminishes as human beings draw on a vibrant ecology of actions, interactions and coactions. Intricate processes of...... biosemiosis connect signifying bodies with their natural surroundings, cultural activities and subjective experiences. Health stretches all the way from the ecosocial surroundings, through the skin and into the self-organizing processes of every living cell. Signifying Bodies lays out a new approach to health...... and health care. Eschewing all forms of dualism, the authors emphasise the interdependency of how we act, think, feel and function. They advocate a relational turn in health care, in which bodies live and learn from suffering and care. In this view, health is inseparable from both living beings and...

  20. Body Imaging

    Science.gov (United States)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images.

  1. Urey prize lecture: On the diversity of plausible planetary systems

    Science.gov (United States)

    Lissauer, J. J.

    1995-01-01

    Models of planet formation and of the orbital stability of planetary systems are used to predict the variety of planetary and satellite systems that may be present within our galaxy. A new approximate global criterion for orbital stability of planetary systems based on an extension of the local resonance overlap criterion is proposed. This criterion implies that at least some of Uranus' small inner moons are significantly less massive than predicted by estimates based on Voyager volumes and densities assumed to equal that of Miranda. Simple calculations (neglecting planetary gravity) suggest that giant planets which acrete substantial amounts of gas while their envelopes are extremely distended ultimately rotate rapidly in the prgrade direction.

  2. UNIFIED REPRESENTATION FOR COLLABORATIVE VISUALIZATION OF PLANETARY TERRAIN DATA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to apply to planetary terrain mapping an alternative, multiresolution method, subdivision surfaces (subdivs), in place of conventional digital elevation...

  3. Simultaneous Localization and Mapping for Planetary Surface Mobility Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC and Carnegie Mellon University have formed a partnership to commercially develop localization and mapping technologies for planetary rovers....

  4. Precision Time Protocol Based Trilateration for Planetary Navigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's vision for planetary exploration requires development and field testing of the key technologies required for extended habitation. To support extended lunar...

  5. Interdisciplinary research produces results in understanding planetary dunes

    Science.gov (United States)

    Titus, Timothy N.; Hayward, Rosalyn K.; Dinwiddie, Cynthia L.

    2012-01-01

    Third International Planetary Dunes Workshop: Remote Sensing and Image Analysis of Planetary Dunes; Flagstaff, Arizona, 12–16 June 2012. This workshop, the third in a biennial series, was convened as a means of bringing together terrestrial and planetary researchers from diverse backgrounds with the goal of fostering collaborative interdisciplinary research. The small-group setting facilitated intensive discussions of many problems associated with aeolian processes on Earth, Mars, Venus, Titan, Triton, and Pluto. The workshop produced a list of key scientifc questions about planetary dune felds.

  6. Planetary Boundaries: Exploring the Safe Operating Space for Humanity

    Directory of Open Access Journals (Sweden)

    Brian Walker

    2009-12-01

    Full Text Available Anthropogenic pressures on the Earth System have reached a scale where abrupt global environmental change can no longer be excluded. We propose a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental- to planetary-scale systems. We have identified nine planetary boundaries and, drawing upon current scientific understanding, we propose quantifications for seven of them. These seven are climate change (CO2 concentration in the atmosphere

  7. The role of small missions in planetary and lunar exploration

    Science.gov (United States)

    1995-01-01

    The Space Studies Board of the National Research Council charged its Committee on Planetary and Lunar Exploration (COMPLEX) to (1) examine the degree to which small missions, such as those fitting within the constraints of the Discovery program, can achieve priority objectives in the lunar and planetary sciences; (2) determine those characteristics, such as level of risk, flight rate, target mix, university involvement, technology development, management structure and procedures, and so on, that could allow a successful program; (3) assess issues, such as instrument selection, mission operations, data analysis, and data archiving, to ensure the greatest scientific return from a particular mission, given a rapid deployment schedule and a tightly constrained budget; and (4) review past programmatic attempts to establish small planetary science mission lines, including the Planetary Observers and Planetary Explorers, and consider the impact management practices have had on such programs. A series of small missions presents the planetary science community with the opportunity to expand the scope of its activities and to develop the potential and inventiveness of its members in ways not possible within the confines of large, traditional programs. COMPLEX also realized that a program of small planetary missions was, in and of itself, incapable of meeting all of the prime objectives contained in its report 'An Integrated Strategy for the Planetary Sciences: 1995-2010.' Recommendations are provided for the small planetary missions to fulfill their promise.

  8. High Performance Monopropellants for Future Planetary Ascent Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to design, develop, and demonstrate, a novel high performance monopropellant for application in future planetary ascent vehicles....

  9. Advanced Planetary Protection Technologies for the Proposed Future Mission Set

    Science.gov (United States)

    Spry, J. Andy; Conley, Catharine A

    2013-01-01

    Planetary protection is the discipline of protecting solar system objects from harmful contamination resulting from the activities of interplanetary spacecraft, and of similarly protecting the Earth from uncontrolled release of a putative extra-terrestrial organism from returned extra-terrestrial samples. Planetary protection requirements for Mars are becoming further refined as more is understood about the nature of the Martian environment as a potential habitat. Likewise, increased understanding of the limits of life on Earth is informing planetary protection policy. This presentation will discuss recent technology developments, ongoing work and future challenges of implementing planetary protection for the proposed future mission set.

  10. Planetary Boundaries: Exploring the Safe Operating Space for Humanity

    DEFF Research Database (Denmark)

    Richardson, Katherine; Rockström, Johan; Steffen, Will;

    2009-01-01

    Anthropogenic pressures on the Earth System have reached a scale where abrupt global environmental change can no longer be excluded. We propose a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one...... or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental- to planetary-scale systems. We have identified nine planetary boundaries and, drawing upon current scientific...... background weathering of P); global freshwater use (system change (

  11. Directed energy missions for planetary defense

    Science.gov (United States)

    Lubin, Philip; Hughes, Gary B.; Eskenazi, Mike; Kosmo, Kelly; Johansson, Isabella E.; Griswold, Janelle; Pryor, Mark; O'Neill, Hugh; Meinhold, Peter; Suen, Jonathan; Riley, Jordan; Zhang, Qicheng; Walsh, Kevin; Melis, Carl; Kangas, Miikka; Motta, Caio; Brashears, Travis

    2016-09-01

    Directed energy for planetary defense is now a viable option and is superior in many ways to other proposed technologies, being able to defend the Earth against all known threats. This paper presents basic ideas behind a directed energy planetary defense system that utilizes laser ablation of an asteroid to impart a deflecting force on the target. A conceptual philosophy called DE-STAR, which stands for Directed Energy System for Targeting of Asteroids and exploration, is an orbiting stand-off system, which has been described in other papers. This paper describes a smaller, stand-on system known as DE-STARLITE as a reduced-scale version of DE-STAR. Both share the same basic heritage of a directed energy array that heats the surface of the target to the point of high surface vapor pressure that causes significant mass ejection thus forming an ejection plume of material from the target that acts as a rocket to deflect the object. This is generally classified as laser ablation. DE-STARLITE uses conventional propellant for launch to LEO and then ion engines to propel the spacecraft from LEO to the near-Earth asteroid (NEA). During laser ablation, the asteroid itself provides the propellant source material; thus a very modest spacecraft can deflect an asteroid much larger than would be possible with a system of similar mission mass using ion beam deflection (IBD) or a gravity tractor. DE-STARLITE is capable of deflecting an Apophis-class (325 m diameter) asteroid with a 1- to 15-year targeting time (laser on time) depending on the system design. The mission fits within the rough mission parameters of the Asteroid Redirect Mission (ARM) program in terms of mass and size. DE-STARLITE also has much greater capability for planetary defense than current proposals and is readily scalable to match the threat. It can deflect all known threats with sufficient warning.

  12. Risk to civilization: A planetary science perspective

    International Nuclear Information System (INIS)

    One of the most profound changes in our perspective of the solar system resulting from the first quarter century of planetary exploration by spacecraft is the recognition that planets, including Earth, were bombarded by cosmic projectiles for 4.5 aeons and continue to be bombarded today. Although the planetary cratering rate is much lower now than it was during the first 0.5 aeons, sizeable Earth-approaching asteroids and comets continue to hit the Earth at a rate that poses a finite risk to civilization. The evolution of this planetary perspective on impact cratering is gradual over the last two decades. It took explorations of Mars and Mercury by early Mariner spacecraft and of the outer solar system by the Voyagers to reveal the significance of asteroidal and cometary impacts in shaping the morphologies and even chemical compositions of the planets. An unsettling implication of the new perspective is addressed: the risk to human civilization. Serious scientific attention was given to this issue in July 1981 at a NASA-sponsored Spacewatch Workshop in Snowmass, Colorado. The basic conclusion of the 1981 NASA sponsored workshop still stands: the risk that civilization might be destroyed by impact with an as-yet-undiscovered asteroid or comet exceeds risk levels that are sometimes deemed unacceptable by modern societies in other contexts. Yet these impact risks have gone almost undiscussed and undebated. The tentative quantitative assessment by some members of the 1981 workshop was that each year, civilization is threatened with destruction with a probability of about 1 in 100,000. The enormous spread in risk levels deemed by the public to be at the threshold of acceptability derives from a host of psychological factors that were widely discussed in the risk assessment literature

  13. Body Rainbow

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    Phubu did not know how long hehad walked after leaving Baxoi, buthe did know that he was halfwaybetween home and Lhasa. Feelingthe weight of the sack containingPhumo's body on his back, Fhubuhad calmed down from the grief anddesperation. He had just one wish:to carry Phumo to Lhasa. He knewthat Phumo had gone, and her soulwas no longer in this body. But hewas determined to finish the trip, notonly because he had promised so, butalso that he believed that it would beredemption for him.

  14. Sacralising Bodies

    DEFF Research Database (Denmark)

    Kaur, Ravinder

    2010-01-01

    sacralisation is realised through co-production within a social setting when the object of sacralisation is recognised as such by others. In contemporary Iran, however, the moment of sacralising bodies by the state is also the moment of its own subversion as the political-theological field of martyrdom is......-sacrifice became central to the mass mobilisation against the monarchy. Once the revolutionary government came into existence, this sacred tradition was regulated to create ‘martyrs’ as a fixed category, in order to consolidate the legacy of the revolution. In this political theatre, the dead body is a site of...

  15. The formation of bipolar planetary nebulae

    OpenAIRE

    Mellema, Garrelt

    1997-01-01

    Using a radiation-hydrodynamics code I follow the formation of planetary nebulae around stars of different mass. Because a more massive central star evolves much faster than a lower mass one, it is to be expected that this will affect the formation of the PN. For the stars I use the evolutionary tracks for remnants with masses of 0.605 M0 and 0.836 M0, taken from Bloecker (1995). The AGB wind is assumed to be concentrated in a thin disk, which in models without evolving stars leads to the for...

  16. Developing the Planetary Science Virtual Observatory

    Science.gov (United States)

    Erard, Stéphane; Cecconi, Baptiste; Le Sidaner, Pierre; Henry, Florence; Chauvin, Cyril; Berthier, Jérôme; André, Nicolas; Génot, Vincent; Schmitt, Bernard; Capria, Teresa; Chanteur, Gérard

    2015-08-01

    In the frame of the Europlanet-RI program, a prototype Virtual Observatory dedicated to Planetary Science has been set up. Most of the activity was dedicated to the definition of standards to handle data in this field. The aim was to facilitate searches in big archives as well as sparse databases, to make on-line data access and visualization possible, and to allow small data providers to make their data available in an interoperable environment with minimum effort. This system makes intensive use of studies and developments led in Astronomy (IVOA), Solar Science (HELIO), and space archive services (IPDA).The current architecture connects existing data services with IVOA or IPDA protocols whenever relevant. However, a more general standard has been devised to handle the specific complexity of Planetary Science, e.g. in terms of measurement types and coordinate frames. This protocol, named EPN-TAP, is based on TAP and includes precise requirements to describe the contents of a data service (Erard et al Astron & Comp 2014). A light framework (DaCHS/GAVO) and a procedure have been identified to install small data services, and several hands-on sessions have been organized already. The data services are declared in standard IVOA registries. Support to new data services in Europe will be provided during the proposed Europlanet H2020 program, with a focus on planetary mission support (Rosetta, Cassini…).A specific client (VESPA) has been developed at VO-Paris (http://vespa.obspm.fr). It is able to use all the mandatory parameters in EPN-TAP, plus extra parameters from individual services. A resolver for target names is also available. Selected data can be sent to VO visualization tools such as TOPCAT or Aladin though the SAMP protocol.Future steps will include the development of a connection between the VO world and GIS tools, and integration of heliophysics, planetary plasma and reference spectroscopic data.The EuroPlaNet-RI project was funded by the European

  17. ANALYSIS METHOD OF AUTOMATIC PLANETARY TRANSMISSION KINEMATICS

    Directory of Open Access Journals (Sweden)

    Józef DREWNIAK

    2014-06-01

    Full Text Available In the present paper, planetary automatic transmission is modeled by means of contour graphs. The goals of modeling could be versatile: ratio calculating via algorithmic equation generation, analysis of velocity and accelerations. The exemplary gears running are analyzed, several drives/gears are consecutively taken into account discussing functional schemes, assigned contour graphs and generated system of equations and their solutions. The advantages of the method are: algorithmic approach, general approach where particular drives are cases of the generally created model. Moreover, the method allows for further analyzes and synthesis tasks e.g. checking isomorphism of design solutions.

  18. Planetary maps - Passports for the mind

    International Nuclear Information System (INIS)

    The various types of planetary maps are reviewed. Included are basic descriptions of planimetric, topographic, geologic, and digital maps. It is noted that planimetric maps are pictorial representations of a planet's round surface flattened into a plane, such as controlled photomosaic maps and shaded relief maps. Topographic maps, those usually made with data from altimeters and stereoscopic images, have contour lines indicating the shapes and elevations of landforms. Geologic maps carry additional information about landforms, such as rock types, the processes that formed them, and their relative ages. The International Astronomical Union nomenclature system is briefly discussed, pointing out that the Union often assigns themes to areas to be mapped

  19. Planetary surface reactor shielding using indigenous materials

    International Nuclear Information System (INIS)

    The exploration and development of Mars will require abundant surface power. Nuclear reactors are a low-cost, low-mass means of providing that power. A significant fraction of the nuclear power system mass is radiation shielding necessary for protecting humans and/or equipment from radiation emitted by the reactor. For planetary surface missions, it may be desirable to provide some or all of the required shielding from indigenous materials. This paper examines shielding options that utilize either purely indigenous materials or a combination of indigenous and nonindigenous materials

  20. X-ray Observations of Planetary Nebulae

    OpenAIRE

    Guerrero, M. A.; Chu, Y.-H.; Gruendl, R A

    2003-01-01

    Planetary nebulae (PNe) are an exciting addition to the zoo of X-ray sources. Recent Chandra and XMM-Newton observations have detected diffuse X-ray emission from shocked fast winds in PN interiors as well as bow-shocks of fast collimated outflows impinging on the nebular envelope. Point X-ray sources associated with PN central stars are also detected, with the soft X-ray (>0.5 keV) emission from instability shocks in the fast stellar wind itself or from a low-mass companion's coronal activit...

  1. Automatic extraction of planetary image features

    Science.gov (United States)

    LeMoigne-Stewart, Jacqueline J. (Inventor); Troglio, Giulia (Inventor); Benediktsson, Jon A. (Inventor); Serpico, Sebastiano B. (Inventor); Moser, Gabriele (Inventor)

    2013-01-01

    A method for the extraction of Lunar data and/or planetary features is provided. The feature extraction method can include one or more image processing techniques, including, but not limited to, a watershed segmentation and/or the generalized Hough Transform. According to some embodiments, the feature extraction method can include extracting features, such as, small rocks. According to some embodiments, small rocks can be extracted by applying a watershed segmentation algorithm to the Canny gradient. According to some embodiments, applying a watershed segmentation algorithm to the Canny gradient can allow regions that appear as close contours in the gradient to be segmented.

  2. Can planetary instability explain the Kepler dichotomy?

    OpenAIRE

    Johansen, Anders; Davies, Melvyn B.; Church, Ross P.; Holmelin, Viktor

    2012-01-01

    The planet candidates discovered by the Kepler mission provide a rich sample to constrain the architectures and relative inclinations of planetary systems within approximately 0.5 AU of their host stars. We use the triple-transit systems from the Kepler 16-months data as templates for physical triple-planet systems and perform synthetic transit observations. We find that all the Kepler triple-transit and double-transit systems can be produced from the triple-planet templates, given a low mutu...

  3. Nonlinear symmetric stability of planetary atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, J.C. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies; Shepherd, T.G. [Toronto Univ., ON (Canada). Dept. of Physics

    1994-11-01

    The energy-Casimir method is applied to the problem of symmetric stability in the context of a compressible, hydrostatic planetary atmosphere with a general equation of state. Linear stability criteria for symmetric disturbances to a zonally symmetric baroclinic flow are obtained. In the special case of a perfect gas the results of Stevens (1983) are recovered. Nonlinear stability conditions are also obtained that, in addition to implying linear stability, provide an upper bound on a certain positive-definite measure of disturbance amplitude.

  4. Space Robotics Planetary Exploration - a DLR Perspective

    OpenAIRE

    Schäfer, Bernd

    2013-01-01

    Scientific exploration of planetary surface like Mars and Earth’s Moon by means of robotic devices and tools is by far more economical than by long-term manned missions, which are almost unlikely to be realized in near future. Moreover, robotic missions are the prerequisite to support and to prepare any future manned exploration mission. NASA has already successfully operated four rovers on Mars, two of them are still under operation. Also ESA will be engaged in Mars surface exploration in 20...

  5. Impact of the frequency dependence of tidal Q on the evolution of planetary systems

    CERN Document Server

    Auclair-Desrotour, P; Mathis, S

    2013-01-01

    Context. Tidal dissipation in planets and in stars is one of the key physical mechanisms that drive the evolution of planetary systems. Aims. Tidal dissipation properties are intrisically linked to the internal structure and the rheology of studied celestial bodies. The resulting dependence of the dissipation upon the tidal frequency is strongly different in the cases of solids and fluids. Methods. We compute the tidal evolution of a two-body coplanar system, using the tidal quality factor's frequency-dependencies appropriate to rocks and to convective fluids. Results. The ensuing orbital dynamics comes out smooth or strongly erratic, dependent on how the tidal dissipation depends upon frequency. Conclusions. We demonstrate the strong impact of the internal structure and of the rheology of the central body on the orbital evolution of the tidal perturber. A smooth frequency-dependence of the tidal dissipation renders a smooth orbital evolution while a peaked dissipation can furnish erratic orbital behaviour.

  6. Planetary Space Weather Services for the Europlanet 2020 Research Infrastructure

    Science.gov (United States)

    André, N.; Grande, M.

    2015-10-01

    Under Horizon 2020, the Europlanet 2020 Research Infrastructure (EPN2020-RI) will include an entirely new Virtual Access Service, WP5 VA1 "Planetary Space Weather Services" (PSWS) that will extend the concepts of space weather and space situational awareness to other planets in our Solar System and in particular to spacecraft that voyage through it. VA1 will make five entirely new 'toolkits' accessible to the research community and to industrial partners planning for space missions: a general planetary space weather toolkit, as well as three toolkits dedicated to the following key planetary environments: Mars (in support ExoMars), comets (building on the expected success of the ESA Rosetta mission), and outer planets (in preparation for the ESA JUICE mission to be launched in 2022). This will give the European planetary science community new methods, interfaces, functionalities and/or plugins dedicated to planetary space weather in the tools and models available within the partner institutes. It will also create a novel event-diary toolkit aiming at predicting and detecting planetary events like meteor showers and impacts. A variety of tools (in the form of web applications, standalone software, or numerical models in various degrees of implementation) are available for tracing propagation of planetary and/or solar events through the Solar System and modelling the response of the planetary environment (surfaces, atmospheres, ionospheres, and magnetospheres) to those events. But these tools were not originally designed for planetary event prediction and space weather applications. So WP10 JRA4 "Planetary Space Weather Services" (PSWS) will provide the additional research and tailoring required to apply them for these purposes. The overall objectives of this JRA will be to review, test, improve and adapt methods and tools available within the partner institutes in order to make prototype planetary event and space weather services operational in Europe at the end of

  7. INPOP06: a new planetary ephemeris

    Science.gov (United States)

    Fienga, A.; Manche, H.; Laskar, J.; Gastineau, M.

    2006-08-01

    INPOP06 is the new numerical planetary ephemeris developed at the IMCCE-Observatoire de Paris. INPOP (Intégrateur numérique planétaire de l' Observatoire de Paris) is a numerical integration of the motion of the nine planets and the moon fitted to the most accurate avalaible observations. It also integrate the motion of 300 perturbing main belt asteroids, the rotation of the Earth and the moon libration. We used more then 45000 observations including the last tracking data of the MGS and Mars Odyssey missions. The accuracy obtained with INPOP06 is comparable to the last versions of the JPL DE solutions (DE414, Standish 05) and of the EPM solutions (EPM04, Pitjeva 05). The interesting point with INPOP is the complete consistency of the dynamical modelling since Earth rotation, moon libration and asteroid orbits are integrated with the main equations of the planetary motions. Two versions of INPOP exists: one using the TDB time scale, the other based on the TCB time scale.

  8. Planetary Nebulae and How to Observe Them

    CERN Document Server

    Griffiths, Martin

    2012-01-01

    Astronomers' Observing Guides provide up-to-date information for amateur astronomers who want to know all about what is it they are observing. This is the basis of the first part of the book. The second part details observing techniques for practical astronomers, working with a range of different instruments. Planetary Nebulae and How to Observe Them is intended for amateur astronomers who want to concentrate on one of the most beautiful classes of astronomical objects in the sky. This book will help the observer to see these celestial phenomena using telescopes of various apertures. As a Sun-like star reaches the end of its life, its hydrogen fuel starts to run out. It collapses until helium nuclei begin nuclear fusion, whereupon the star begins to pulsate, each pulsation throwing off a layer of the star's atmosphere. Eventually the atmosphere has all been ejected as an expanding cloud of gas, the star's core is exposed and ultraviolet photons cause the shell of gas to glow brilliantly - that's planetary ...

  9. InSight Planetary Protection Status

    Science.gov (United States)

    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 (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.

  10. Planetary nebula progenitors that swallow binary systems

    CERN Document Server

    Soker, Noam

    2015-01-01

    I propose that some irregular `messy' planetary nebulae owe their morphologies to triple-stellar evolution where tight binary systems are tidally and frictionally destroyed inside the envelope of asymptotic giant branch (AGB) stars. The tight binary system might breakup with one star leaving the system. In an alternative evolution, one of the stars of the brook-up tight binary system falls toward the AGB envelope with low specific angular momentum, and drowns in the envelope. In a different type of destruction process the drag inside the AGB envelope causes the tight binary system to merge. This releases gravitational energy within the AGB envelope, leading to a very asymmetrical envelope ejection, with an irregular and `messy' planetary nebula as a descendant. The evolution of the triple-stellar system before destruction can be in a full common envelope evolution (CEE) or in a grazing envelope evolution (GEE). Both before and after destruction the system might lunch pairs of opposite jets. One pronounced sig...

  11. Directed Energy Missions for Planetary Defense

    CERN Document Server

    Lubin, Philip; Eskenazi, Mike; Kosmo, Kelly; Johansson, Isabella E; Griswold, Janelle; Pryor, Mark; O'Neill, Hugh; Meinhold, Peter; Suen, Jonathon; Riley, Jordan; Zhang, Qicheng; Walsh, Kevin; Melis, Carl; Kangas, Miikka; Motta, Caio; Brashears, Travis

    2016-01-01

    Directed energy for planetary defense is now a viable option and is superior in many ways to other proposed technologies, being able to defend the Earth against all known threats. This paper presents basic ideas behind a directed energy planetary defense system that utilizes laser ablation of an asteroid to impart a deflecting force on the target. A conceptual philosophy called DE-STAR, which stands for Directed Energy System for Targeting of Asteroids and exploRation, is an orbiting stand-off system, which has been described in other papers. This paper describes a smaller, stand-on system known as DE-STARLITE as a reduced-scale version of DE-STAR. Both share the same basic heritage of a directed energy array that heats the surface of the target to the point of high surface vapor pressure that causes significant mass ejection thus forming an ejection plume of material from the target that acts as a rocket to deflect the object. This is generally classified as laser ablation. DE-STARLITE uses conventional prop...

  12. Planetary companion in K giant Sigma Persei

    CERN Document Server

    Lee, Byeong-Cheol; Park, Myeong-Gu; Mkrtichian, David E; Jeong, Gwanghui; Kim, Kang-Min; Valyavin, Gennady

    2014-01-01

    We report the detection of an exoplanet candidate in orbit around sigma Persei from a radial velocity (RV) survey. The system exhibits periodic RV variations of 579.8 +/- 2.4 days. The purpose of the survey is to search for low-amplitude and long-period RV variations in giants and examine the origin of the variations using the fiber-fed Bohyunsan Observatory Echelle Spectrograph installed at the 1.8-m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We present high-accuracy RV measurements of sigma Per made from December 2003 to January 2014. We argue that the RV variations are not related to the surface inhomogeneities but instead a Keplerian motion of the planetary companion is the most likely explanation. Assuming a stellar mass of 2.25 +/- 0.5 M_Sun, we obtain a minimum planetary companion mass of 6.5 +/- 1.0 M_Jup, with an orbital semi-major axis of 1.8 +/- 0.1 AU, and an eccentricity of 0.3 +/- 0.1 around sigma Per.

  13. Molecular line mapping of (young) planetary nebulae

    Science.gov (United States)

    Bujarrabal, Valentín

    2016-07-01

    In this contribution, I will review recent results obtained from high-resolution observations of molecular emission of planetary nebulae in the millimeter and submillimeter waves, stressing the easy interpretation of the data and the great amount of quantitative results obtained from them. Radio interferometers have been shown to be very efficient in the observation of our objects and, particularly since the arrival of ALMA, the amount of results is becoming impressive. We will deal mainly with young planetary nebulae or protoplanetary nebulae, since, as we will see, molecular lines tend to be weak in evolved objects because of photodissociation. In relatively young nebulae, the molecular gas represents most of the nebular material and can be well observed in line emission in mm- and submm-waves. Those observations have yielded many quantitative and accurate results on the structure, dynamics, and physical conditions of this largely dominant nebular component. In more evolved sources, we can follow the evolution of the chemical composition, although the data become rare.

  14. Bringing Planetary Science to the Public

    Science.gov (United States)

    Chapman, C. R.

    1999-09-01

    Since I am not fluent in Italian, I won't presume to give a "public" science lecture in Padua (that will happen in the year 2000 before an English-speaking audience). But I will discuss the gap between the arcane practice of planetary research and the yearnings of a poorly educated public to participate in planetary exploration. Education and public outreach (E&PO) is a vital enterprise for our profession to be engaged in. But that does not mean that every researcher needs to become proficient at public communication. Our interdisciplinary field advances because of our diverse talents and we should do what we are good at. It is good that entities like the DPS and NASA are encouraging scientists to engage in E&PO, yet I fear that this endeavor is already, in its infancy, becoming bureaucratized. An E&PO cottage industry is developing, complete with its own jargon and checklists. The essential thing is for us all to realize that science is a human activity, supported by the public as part of our civilization's culture. As we do our science, we should do it with consciousness of our public role and use whatever creative talents we have to synthesize our specialized results for the broader scientific community, to articulate them to science communicators (educators, journalists, writers), and to share them directly with the public.

  15. Recent progress in exobiology and planetary biology

    Science.gov (United States)

    Jukes, T. H.

    1981-01-01

    Recent work in the fields of exobiology, the study of the possible characteristics of extraterrestrial life, and planetary biology, the study of life forms as a function of planetary conditions, is reviewed. Searches conducted for life on Mars by the Viking Landers and on Titan by Voyager 1 are considered, and the origin of life on earth is considered in relation to the question of the inorganic trace elements in living systems that are required for life. The question of the origin of terrestrial life from spores carried through the interstellar medium is examined, and the unlikelihood of the survival of such spores except within meteorites or dust particles is pointed out. Studies of organic molecules present in the interstellar medium are indicated as evidence that the conditions necessary for the formation of life can exist in various locations throughout the universe. Investigations of the molecular evolution of life on earth and of life under extreme conditions of heat, cold, drought and ultraviolet radiation, and of the organic compounds found in meteorites and comets are also discussed. The importance of a mechanism of heredity, such as terrestrial DNA, to the evolution of terrestrial and possible extraterrestrial life is pointed out.

  16. Using Vulcan to Recreate Planetary Cores

    CERN Document Server

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

    2001-01-01

    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 l...

  17. Observations of an extreme planetary system

    Science.gov (United States)

    Raetz, Stefanie; Schmidt, Tobias O. B.; Briceno, Cesar; Neuhäuser, Ralph

    2015-12-01

    Almost 500 planet host stars are already known to be surrounded by more than one planet. Most of them (except HR8799) are old and all planets were found with the same or similar detection method.We present an unique planetary system. For the first time, a close in transiting and a wide directly imaged planet are found to orbit a common host star which is a low mass member of a young open cluster. The inner candidate is the first possible young transiting planet orbiting a previously known weak-lined T-Tauri star and was detected in our international monitoring campaign of young stellar clusters. The transit shape is changing between different observations and the transit even disappears and reappears. This unusual transit behaviour can be explained by a precessing planet transiting a gravity-darkened star.The outer candidate was discovered in the course of our direct imaging survey with NACO at ESO/VLT. Both objects are consistent with a migration time-scales and their relation to protoplanetary disc lifetimes. Furthermore, this system with two planets on such extreme orbits gives us the opportunity to study the possible outcome of planet-planet scattering theories for the first time by observations.I will report on our monitoring and photometric follow-up observations as well as on the direct detection and the integral field spectroscopy of this extreme planetary system.

  18. Hyperbolic Orbits and the Planetary Flylby Anomaly

    Science.gov (United States)

    Wilson, T.L.; Blome, H.J.

    2009-01-01

    Space probes in the Solar System have experienced unexpected changes in velocity known as the flyby anomaly [1], as well as shifts in acceleration referred to as the Pioneer anomaly [2-4]. In the case of Earth flybys, ESA s Rosetta spacecraft experienced the flyby effect and NASA s Galileo and NEAR satellites did the same, although MESSENGER did not possibly due to a latitudinal property of gravity assists. Measurements indicate that both anomalies exist, and explanations have varied from the unconventional to suggestions that new physics in the form of dark matter might be the cause of both [5]. Although dark matter has been studied for over 30 years, there is as yet no strong experimental evidence supporting it [6]. The existence of dark matter will certainly have a significant impact upon ideas regarding the origin of the Solar System. Hence, the subject is very relevant to planetary science. We will point out here that one of the fundamental problems in science, including planetary physics, is consistency. Using the well-known virial theorem in astrophysics, it will be shown that present-day concepts of orbital mechanics and cosmology are not consistent for reasons having to do with the flyby anomaly. Therefore, the basic solution regarding the anomalies should begin with addressing the inconsistencies first before introducing new physics.

  19. Orbital Stability of High Mass Planetary Systems

    Science.gov (United States)

    Morrison, Sarah J.; Kratter, Kaitlin M.

    2016-05-01

    In light of the observation of systems like HR 8799 that contain several planets with planet-star mass ratios larger than Jupiter's, we explore the relationships between planet separation, mass, and stability timescale for high mass multi-planet systems detectable via direct imaging. We discuss the role of overlap between 1st and sometimes 2nd order mean motion resonances, and show how trends in stability time vary from previous studies of lower mass multi-planet systems. We show that extrapolating empirically derived relationships between planet mass, separation, and stability timescale derived from lower mass planetary systems misestimate the stability timescales for higher mass planetary systems by more than an order of magnitude at separations near the Hill stability limit. We also address what metrics of planet separation are most useful for estimating a system's dynamical stability. We apply these results to young, gapped, debris disk systems of the ScoCen association in order to place limits on the maximum mass and number of planets that could persist for the lifetimes of the disks. These efforts will provide useful constraints for on-going direct imaging surveys. By setting upper limits on the most easily detectable systems, we can better interpret both new discoveries and non-dectections.

  20. Planetary Protection Considerations For Exomars Meteorological Instrumentation.

    Science.gov (United States)

    Camilletti, Adam

    2007-10-01

    Planetary protection requirements for Oxford University's contribution to the upcoming ESA ExoMars mission are discussed and the current methods being used to fulfil these requirements are detailed and reviewed. Oxford University is supplying temperature and wind sensors to the mission and since these will be exposed to the Martian environment there is a requirement that they are sterilised to stringent COSPAR standards adhered to by ESA. Typically dry heat microbial reduction (DHMR) is used to reduce spacecraft bioburden but the high temperatures involved are not compatible with the some hardware elements. Alternative, low-temperature sterilisation methods are reviewed and their applicability to spacecraft hardware discussed. The use of a commercially available, bench-top endotoxin tester in planetary protection is also discussed and data from preliminary tests performed at Oxford are presented. These devices, which utilise the immune response of horseshoe crabs to the presence of endotoxin, have the potential to reduce the time taken to determine bioburden by removing the need for conventional assaying -a lengthy and sometimes expensive process.

  1. Abundances in the Planetary Nebula IC 5217

    Science.gov (United States)

    Hyung, Siek; Aller, Lawrence H.; Feibelman, Walter A.; Lee, Woo-Baik; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    High resolution optical wavelength spectroscopic data were secured in the optical wavelengths, 3700A - 10,050A, for the planetary nebula IC 5217 with the Hamilton Echelle Spectrograph at Lick Observatory. These optical spectra have been analyzed along with the near-UV and UV archive data. Diagnostic analyses indicate a nebular physical condition with electron temperature of about 10,700 K (from the [O III] lines) and the density of N(sub epsilon) = 5000/cm. Ionic concentrations have been derived with the representative diagnostics, and with the aid of a photoionization model construction, we derived the elemental abundances. Contrary to the previous studies found in the literature, He and C appear to be depleted compared to the average planetary nebula and to the Sun (and S marginally so), while the remaining elements appear to be close to the average value. IC 5217 may have evolved from an O-rich progenitor and the central star temperature of IC 5217 is likely to be 92,000 K.

  2. Chaotic diffusion in the Gliese-876 planetary system

    Science.gov (United States)

    Martí, J. G.; Cincotta, P. M.; Beaugé, C.

    2016-07-01

    Chaotic diffusion is supposed to be responsible for orbital instabilities in planetary systems after the dissipation of the protoplanetary disc, and a natural consequence of irregular motion. In this paper, we show that resonant multiplanetary systems, despite being highly chaotic, not necessarily exhibit significant diffusion in phase space, and may still survive virtually unchanged over time-scales comparable to their age. Using the GJ-876 system as an example, we analyse the chaotic diffusion of the outermost (and less massive) planet. We construct a set of stability maps in the surrounding regions of the Laplace resonance. We numerically integrate ensembles of close initial conditions, compute Poincaré maps and estimate the chaotic diffusion present in this system. Our results show that, the Laplace resonance contains two different regions: an inner domain characterized by low chaoticity and slow diffusion, and an outer one displaying larger values of dynamical indicators. In the outer resonant domain, the stochastic borders of the Laplace resonance seem to prevent the complete destruction of the system. We characterize the diffusion for small ensembles along the parameters of the outermost planet. Finally, we perform a stability analysis of the inherent chaotic, albeit stable Laplace resonance, by linking the behaviour of the resonant variables of the configurations to the different sub-structures inside the three-body resonance.

  3. Volatile Analysis by Pyrolysis of Regolith for Planetary Resource Exploration

    Science.gov (United States)

    Glavin, Daniel P.; Malespin, Charles; ten Kate, Inge L.; Getty, Stephanie A.; Holmes, Vincent E.; Mumm, Erik; Franz, Heather B.; Noreiga, Marvin; Dobson, Nick; Southard, Adrian E.; Feng, Steven H.; Kotecki, Carl A.; Dworkin, Jason P.; Swindle, Timothy D.; Bleacher, Jacob E.; Rice, James W.; Mahaffy, Paul R.

    2012-01-01

    The extraction and identification of volatile resources that could be utilized by humans including water, oxygen, noble gases, and hydrocarbons on the Moon, Mars, and small planetary bodies will be critical for future long-term human exploration of these objects. Vacuum pyrolysis at elevated temperatures has been shown to be an efficient way to release volatiles trapped inside solid samples. In order to maximize the extraction of volatiles, including oxygen and noble gases from the breakdown of minerals, a pyrolysis temperature of 1400 C or higher is required, which greatly exceeds the maximum temperatures of current state-of-the-art flight pyrolysis instruments. Here we report on the recent optimization and field testing results of a high temperature pyrolysis oven and sample manipulation system coupled to a mass spectrometer instrument called Volatile Analysis by Pyrolysis of Regolith (VAPoR). VAPoR is capable of heating solid samples under vacuum to temperatures above 1300 C and determining the composition of volatiles released as a function of temperature.

  4. Formation, Orbital and Internal Evolutions of Young Planetary Systems

    Science.gov (United States)

    Baruteau, Clément; Bai, Xuening; Mordasini, Christoph; Mollière, Paul

    2016-05-01

    The growing body of observational data on extrasolar planets and protoplanetary disks has stimulated intense research on planet formation and evolution in the past few years. The extremely diverse, sometimes unexpected physical and orbital characteristics of exoplanets lead to frequent updates on the mainstream scenarios for planet formation and evolution, but also to the exploration of alternative avenues. The aim of this review is to bring together classical pictures and new ideas on the formation, orbital and internal evolutions of planets, highlighting the key role of the protoplanetary disk in the various parts of the theory. We begin by briefly reviewing the conventional mechanism of core accretion by the growth of planetesimals, and discuss a relatively recent model of core growth through the accretion of pebbles. We review the basic physics of planet-disk interactions, recent progress in this area, and discuss their role in observed planetary systems. We address the most important effects of planets internal evolution, like cooling and contraction, the mass-luminosity relation, and the bulk composition expressed in the mass-radius and mass-mean density relations.

  5. The Inner Debris Structure in the Fomalhaut Planetary System

    CERN Document Server

    Su, Kate Y L; Defrere, Denis; Wang, Kuo-Song; Lai, Shih-Ping; Wilner, David J; van Lieshout, Rik; Lee, Chin-Fei

    2015-01-01

    Fomalhaut plays an important role in the study of debris disks and small bodies in other planetary systems. The proximity and luminosity of the star make key features of its debris, like the water ice-line, accessible. Here we present ALMA cycle 1, 870 \\mu m (345 GHz) observations targeted at the inner part of the Fomalhaut system with a synthesized beam of 0.45"x0.37" (~3 AU linear resolution at the distance of Fomalhaut) and a rms of 26 \\mu Jy/beam. The high angular resolution and sensitivity of the ALMA data enable us to place strong constraints on the nature of the warm excess revealed by Spitzer and Herschel observations. We detect a point source at the star position with a total flux consistent with thermal emission from the stellar photosphere. No structures that are brighter than 3\\sigma\\ are detected in the central 15 AU x 15 AU region. Modeling the spectral energy distribution using parameters expected for a dust-producing planetesimal belt indicates a radial location in the range ~8-15 AU. This is ...

  6. Planetary Airplane Extraction System Development and Subscale Testing

    Science.gov (United States)

    Teter, John E., Jr.

    2006-01-01

    The Aerial Regional-scale Environmental Survey (ARES) project will employ an airplane as the science platform from which to collect science data in the previously inaccessible, thin atmosphere of Mars. In order for the airplane to arrive safely in the Martian atmosphere, a number of sequences must occur. A critical element in the entry sequence at Mars is an extraction maneuver to separate the airplane quickly (in less than a second) from its protective backshell to reduce the possibility of re-contact, potentially leading to mission failure. This paper describes the development, testing, and lessons learned from building a 1/3 scale model of this airplane extraction system. This design, based on the successful Mars Exploration Rover (MER) extraction mechanism, employs a series of trucks rolling along tracks located on the surface of the central parachute can. Numerous tests using high speed video were conducted at the Langley Research Center to validate this concept. One area of concern was that that although the airplane released cleanly, a pitching moment could be introduced. While targeted for a Mars mission, this concept will enable environmental surveys by aircraft in other planetary bodies with a sensible atmosphere such as Venus or Saturn's moon, Titan.

  7. Magnetism, planetary rotation and convection in the solar system

    CERN Document Server

    1985-01-01

    On the 6th, 7th' and 8th April 1983, a conference entitled "Magnetism, planetary rotation and convection in the Solar System" was held in the School of Physics at the University of Newcastle upon Tyne. The purpose of the meeting was to celebrate the 60th birthday of Prof. Stanley Keith Runcorn and his, and his students' and associates', several decades of scientific achievement. The social programme, which consisted of excursions in Northumberland and Durham with visits to ancient castles and churches, to Hexham Abbey and Durham Cathedral, and dinners in Newcastle and Durham, was greatly enjoyed by those attending the meeting and by their guests. The success ofthe scientific programme can be judged by this special edition of Geophysical Surveys which is derived mainly from the papers given at the meeting. The story starts in the late 1940s when the question of the origin of the magnetic field of the Earth and such other heavenly bodies as had at that time been discovered as having a magnetic field, was exerci...

  8. Isotopic enrichment of forming planetary systems from supernova pollution

    Science.gov (United States)

    Lichtenberg, Tim; Parker, Richard J.; Meyer, Michael R.

    2016-08-01

    Heating by short-lived radioisotopes (SLRs) such as 26Al and 60Fe fundamentally shaped the thermal history and interior structure of Solar System planetesimals during the early stages of planetary formation. The subsequent thermo-mechanical evolution, such as internal differentiation or rapid volatile degassing, yields important implications for the final structure, composition and evolution of terrestrial planets. SLR-driven heating in the Solar System is sensitive to the absolute abundance and homogeneity of SLRs within the protoplanetary disk present during the condensation of the first solids. In order to explain the diverse compositions found for extrasolar planets, it is important to understand the distribution of SLRs in active planet formation regions (star clusters) during their first few Myr of evolution. By constraining the range of possible effects, we show how the imprint of SLRs can be extrapolated to exoplanetary systems and derive statistical predictions for the distribution of 26Al and 60Fe based on N-body simulations of typical to large clusters (103-104 stars) with a range of initial conditions. We quantify the pollution of protoplanetary disks by supernova ejecta and show that the likelihood of enrichment levels similar to or higher than the Solar System can vary considerably, depending on the cluster morphology. Furthermore, many enriched systems show an excess in radiogenic heating compared to Solar System levels, which implies that the formation and evolution of planetesimals could vary significantly depending on the birth environment of their host stars.

  9. Planetary Space Sciences and Data Management

    Science.gov (United States)

    Stein, Thomas

    The quality of planetary data archives is governed largely by data producers and data archivists. Because each group possesses a nearly unique domain knowledge, it is important for these groups to interact in early mission planning phases, and to continue collaboration through the data acquisition phase and beyond. When communication between the groups is limited, the value of the science data can suffer. This abstract discusses ways in which early and regular interaction between the Planetary Data System and data producers is beneficial. NASA's Planetary Data System (PDS)—-a federation of discipline and support nodes—-provides expertise to guide and assist missions, programs, and individuals to organize and document digital data that can be used to support NASA's goals in planetary science and Solar System exploration. Then, PDS makes these data accessible to users in the scientific community, and ensures the long-term preservation and usability of the data. Data archiving requirements for NASA planetary missions are written into mission announce-ments of opportunity. PDS provides a pre-proposal briefing on data archiving requirements to potential proposers, and the proposal data archiving section is reviewed by PDS. After a mission is selected, one PDS node is designated the "lead node", i.e., the primary PDS group that interacts with mission personnel. At this point, data archiving working groups are formed, and project data management and archive plans are developed to define data to be archived. Additional documents are created that detail data product and archive volume structure. Archive documents and sample data are peer-reviewed by the science community prior to data acquisition. During the active data acquisition phase, raw and processed data products, labels (metadata) and documentation are produced by the mission science team. Preliminary and quick-look data often are made accessible via project and PDS web pages. Data products submitted for

  10. Detection of Planetary Emission from the Exoplanet TrES-2 using Spitzer /IRAC

    CERN Document Server

    O'Donovan, Francis T; Harrington, Joseph; Seager, Sara; Madhusudhan, N; Deming, Drake; Knutson, Heather A

    2009-01-01

    With the recent torrent of discoveries of new transiting planets, there have been ample candidates for observations using the Spitzer Space Telescope. We present here the results of our observations of TrES-2 using the Infrared Array Camera on Spitzer. We monitored this transiting system during two secondary eclipses, when the planetary emission is blocked by the star. The resulting decrease in flux is 0.127%+-0.021%, 0.230%+-0.024%, 0.199%+-0.054%, and 0.359%+-0.060%, at 3.6, 4.5, 5.8, and 8.0 microns, respectively. We show that three of these flux contrasts are well fit by a black body spectrum with Teff = 1500 K, as well as by a more detailed model spectrum of a planetary atmosphere. However, the planet-to-star flux ratio at 4.5 microns exceeds the expectation from the blackbody emission, which argues for a temperature inversion in the atmosphere of TrES-2. The presence or absence of such an inversion in a planetary atmosphere has been predicted to be correlated with the amount of incident flux received by...

  11. On the Stability of Extrasolar Planetary Systems and other Closely Orbiting Pairs

    CERN Document Server

    Adams, Fred C

    2014-01-01

    This paper considers the stability of tidal equilibria for planetary systems in which stellar rotation provides a significant contribution to the angular momentum budget. We begin by applying classic stability considerations for two bodies to planetary systems --- where one mass is much smaller than the other. The application of these stability criteria to a subset of the Kepler sample indicates that the majority of the systems are not in a stable equilibrium state. Motivated by this finding, we generalize the stability calculation to include the quadrupole moment for the host star. In general, a stable equilibrium requires that the total system angular momentum exceeds a minimum value (denoted here as $L_X$) and that the orbital angular momentum of the planet exceeds a minimum fraction of the total. Most, but not all, of the observed planetary systems in the sample have enough total angular momentum to allow an equilibrium state. Even with the generalizations of this paper, however, most systems have too lit...

  12. A Nominal Balloon Instrument Payload to Address Questions from the Planetary Decadal Survey

    Science.gov (United States)

    Young, Eliot; Kremic, Tibor; Dankanich, John

    The Planetary Science Decadal Survey (entitled "Visions and Voyages for Planetary Science in the Decade 2013 - 2022", available online at https://solarsystem.nasa.gov/2013decadal/) serves as a roadmap for activities to be pursued by the Planetary Science Division of NASA's Science Mission Directorate. This document outlines roughly 200 key research areas and questions in chapters covering different parts of the solar system (e.g., Mars, Small Bodies, etc.). We have reviewed the Decadal Survey to assess whether any of the key questions can be addressed by high altitude balloon-borne payloads. Although some questions can only be answered by in situ experiments, we found that approximately one quarter of the key questions were well suited to balloon payloads. In many of those cases, balloons were competitive or superior to other existing facilities, including HST, SOFIA or Keck telescopes. We will present specific telescope and instrument bench designs that are capable of addressing key questions in the Decadal Survey. The instrument bench takes advantage of two of the main benefits of high-altitude observations: diffraction-limited imaging in visible and UV wavelengths and unobstructed spectroscopy in near-IR (1 - 5 microns) wavelengths. Our optical prescription produces diffraction-limited PSFs in both visible and IR beams. We will discuss pointing and thermal stability, two of the main challenges facing a balloon-borne telescope.

  13. 55 CANCRI: A COPLANAR PLANETARY SYSTEM THAT IS LIKELY MISALIGNED WITH ITS STAR

    International Nuclear Information System (INIS)

    Although the 55 Cnc system contains multiple, closely packed planets that are presumably in a coplanar configuration, we use numerical simulations to demonstrate that they are likely to be highly inclined to their parent star's spin axis. Due to perturbations from its distant binary companion, this planetary system precesses like a rigid body about its parent star. Consequently, the parent star's spin axis and the planetary orbit normal likely diverged long ago. Because only the projected separation of the binary is known, we study this effect statistically, assuming an isotropic distribution for wide binary orbits. We find that the most likely projected spin-orbit angle is ∼50°, with a ∼30% chance of a retrograde configuration. Transit observations of the innermost planet—55 Cnc e—may be used to verify these findings via the Rossiter-McLaughlin effect. 55 Cancri may thus represent a new class of planetary systems with well-ordered, coplanar orbits that are inclined with respect to the stellar equator.

  14. Planetary surface photometry and imaging: progress and perspectives

    International Nuclear Information System (INIS)

    Spacecraft have visited and returned many thousands of images and spectra of all of the planets, many of their moons, several asteroids, and a few comet nuclei during the golden age of planetary exploration. The signal in each pixel of each image or spectral channel is a measurement of the radiance of scattered sunlight into a specific direction. The information on the structure and composition of the surface that is contained in variation of the radiance with scattering geometry and wavelength, including polarization state, has only just begun to be exploited and is the topic of this review. The uppermost surfaces of these bodies are mainly composed of particles that are continuously generated by impacts of micrometeoroids and larger impactors. Models of light scattering by distributions of sizes and irregular shapes of particles and by closely packed particles within a surface are challenging. These are active topics of research where considerable progress has recently been made. We focus on the surfaces of bodies lacking atmospheres. These surfaces are diverse and their morphologies give evidence of their evolution by impacts and resurfacing by a variety of processes including down slope movement and electrostatic transport of particles, gravitational accumulation of debris, volatile outgassing and migration, and magnetospheric interactions. Sampling of scattering geometries and spatial resolution is constrained by spacecraft trajectories. However, the large number of archived images and spectra demand more quantitative interpretation. The scattering geometry dependence of the radiance is underutilized and promises constraints on the compositions and structure of the surface for materials that lack diagnostic wavelength dependence. The general problem is considered in terms of the lunar regolith for which samples have been returned to Earth. (report on progress)

  15. A theoretical framework for volcanic degassing chemistry in a comparative planetology perspective and implications for planetary atmospheres

    Science.gov (United States)

    Gaillard, Fabrice; Scaillet, Bruno

    2014-10-01

    Magmatic degassing is ubiquitous and enduring, yet its impact on both planetary surficial chemistry and how it may have varied among planetary systems remains imprecise. A large number of factors are likely to be involved in the control of magmatic gas compositions, leading roles being given to the redox state and volatile abundances in planetary interiors, and the fate of the latter during mantle melting. We however show that the pressure at which degassing occurs, that is the atmospheric pressure in most sensible cases, has a prime influence on the composition of subaerial volcanic gases on planets: high surface pressure produces N2- and CO2-rich and dry volcanic gases, while low pressure promotes sulfur-rich gases. In-between, atmospheric pressures close to 1 bar trigger volcanic gases dominated by H2O. This simple pattern broadly mirrors the atmospheres of Venus-Earth-Mars-Io planetary suite and constitutes benchmarks for the prediction and interpretation of atmospheric features of extra-solar planets. Volatile abundances within the planetary body interiors also matter but they play a secondary role. Furthermore, our analysis shows that any difference in redox conditions prevailing during partial melting tends to disappear with the degassing process itself, converging toward a unique - planetary oxygen fugacity - at the venting pressure. A feedback relationship between volcanic gas compositions and atmospheric pressure implies a runaway drying during atmospheric growth; that is volcanic gases must become CO2 richer as the atmospheric mass increases. This may explain some features of the Venusian atmosphere. On Earth, impact ejection of the atmosphere and CO2-sink mechanisms, such as carbonate precipitation and plate tectonics, must have decreased atmospheric pressure allowing the reestablishment of water-rich volcanic gases.

  16. Orbital structure of the GJ876 extrasolar planetary system, based on the latest Keck and HARPS radial velocity data

    OpenAIRE

    Baluev, Roman V.

    2011-01-01

    We use full available array of radial velocity data, including recently published HARPS and Keck observatory sets, to characterize the orbital configuration of the planetary system orbiting GJ876. First, we propose and describe in detail a fast method to fit perturbed orbital configuration, based on the integration of the sensitivity equations inferred by the equations of the original $N$-body problem. Further, we find that it is unsatisfactory to treat the available radial velocity data for ...

  17. The great escape - III. Placing post-main-sequence evolution of planetary and binary systems in a Galactic context

    OpenAIRE

    Veras, D.; Evans, N. W.; Wyatt, M. C.; Tout, C. A.

    2014-01-01

    Our improving understanding of the life cycle of planetary systems prompts investigations of the role of the Galactic environment before, during and after Asymptotic Giant Branch (AGB) stellar evolution. Here, we investigate the interplay between stellar mass loss, Galactic tidal perturbations, and stellar flybys for evolving stars which host one planet, smaller body or stellar binary companion and reside in the Milky Way's bulge or disc. We find that the potential evolutionary pathways from ...

  18. Planetary boundaries: guiding human development on a changing planet

    NARCIS (Netherlands)

    Steffen, W.; Richardson, K.; Rockström, J.; Cornell, S.E.; Fetzer, I.; Bennett, E.; Biggs, R.; Vries, de W.

    2015-01-01

    The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth System. Here, we revise and update the planetary boundaries framework, with a focus on the underpinning biophysical science, based on t

  19. Uncovering Circumbinary Planetary Architectural Properties from Selection Biases

    CERN Document Server

    Li, Gongjie; Tao, Molei

    2016-01-01

    The new discoveries of circumbinary planetary systems shed light on the understanding of planetary system formation. Learning the architectural properties of these systems is essential for constraining the different formation mechanisms. We first revisit the stability limit of circumbinary planets. Next, we focus on eclipsing stellar binaries and obtain an analytical expression for the transit probability in a realistic setting, where finite observation period and planetary orbital precession are included. Then, understanding of the architectural properties of the currently observed transiting systems is refined, based on Bayesian analysis and a series of hypothesis tests. We find 1) it is not a selection bias that the innermost planets reside near the stability limit for eight of the nine observed systems, and this is consistent with a log uniform distribution of the planetary semi-major axis; 2) it is not a selection bias that the planetary and stellar orbits are nearly coplanar ($\\lesssim 3^\\circ$), and th...

  20. Planetary Atmospheres and Evolution of Complex Life

    Science.gov (United States)

    Catling, D.

    2014-04-01

    Let us define "complex life" as actively mobile organisms exceeding tens of centimeter size scale with specialized, differentiated anatomy comparable to advanced metazoans. Such organisms on any planet will need considerable energy for growth and metabolism, and an atmosphere is likely to play a key role. The history of life on Earth suggests that there were at least two major hurdles to overcome before complex life developed. The first was biological. Large, three-dimensional multicellular animals and plants are made only of eukaryotic cells, which are the only type that can develop into a large, diverse range of cell types unlike the cells of microbes. Exactly how eukaryotes allow 3D multicellularity and how they originated are matters of debate. But the internal structure and bigger and more modular genomes of eukaryotes are important factors. The second obstacle for complex life was having sufficient free, diatomic oxygen (O2). Aerobic metabolism provides about an order of magnitude more energy for a given intake of food than anaerobic metabolism, so anaerobes don't grow multicellular beyond filaments because of prohibitive growth efficiencies. A precursor to a 2.4 Ga rise of oxygen was the evolution of water-splitting, oxygen-producing photosynthesis. But although the atmosphere became oxidizing at 2.4 Ga, sufficient atmospheric O2 did not occur until about 0.6 Ga. Earth-system factors were involved including planetary outgassing (as affected by size and composition), hydrogen escape, and processing of organic carbon. An atmosphere rich in O2 provides the largest feasible energy source per electron transfer in the Periodic Table, which suggests that O2 would be important for complex life on exoplanets. But plentiful O2 is unusual in a planetary atmosphere because O2 is easily consumed in chemical reactions with reducing gases or surface materials. Even with aerobic metabolism, the partial pressure of O2 (pO2) must exceed ~10^3 Pa to allow organisms that rely

  1. An enhanced Planetary Radar Operating Centre (PROC)

    Science.gov (United States)

    Catallo, C.

    2010-12-01

    Planetary exploration by means of radar systems, mainly using GPRs is an important role of Italy and numerous scientific international space programs are carried out jointly with ESA and NASA by Italian Space Agency, the scientific community and the industry. Three experiments under Italian leadership ( designed and manufactured by the Italian industry) provided by ASI within a NASA/ESA/ASI joint venture framework are successfully operating: MARSIS on-board MEX, SHARAD on-board MRO and CASSINI Radar on-board Cassini spacecraft: the missions have been further extended . Three dedicated operational centers, namely SHOC, (Sharad Operating Centre), MOC (Marsis Operating Center) and CASSINI PAD are operating from the missions beginning to support all the scientific communities, institutional customers and experiment teams operation Each center is dedicated to a single instrument management and control, data processing and distribution and even if they had been conceived to operate autonomously and independently one from each other, synergies and overlaps have been envisaged leading to the suggestion of a unified center, the Planetary Radar Processing Center (PROC). In order to harmonize operations either from logistics point of view and from HW/SW capabilities point of view PROC is designed and developed for offering improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation. PROC is, therefore, conceived as the Italian support facility to the scientific community for on-going and future Italian planetary exploration programs, such as Europa-Jupiter System Mission (EJSM) The paper describes how the new PROC is designed and developed, to allow SHOC, MOC and CASSINI PAD to operate as before, and to offer improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation aiding scientists to increase their knowledge in the field of surface

  2. NASA Planetary Science Summer School: Preparing the Next Generation of Planetary Mission Leaders

    Science.gov (United States)

    Lowes, L. L.; Budney, C. J.; Sohus, A.; Wheeler, T.; Urban, A.; NASA Planetary Science Summer School Team

    2011-12-01

    Sponsored by NASA's Planetary Science Division, and managed by the Jet Propulsion Laboratory, the Planetary Science Summer School prepares the next generation of engineers and scientists to participate in future solar system exploration missions. Participants learn the mission life cycle, roles of scientists and engineers in a mission environment, mission design interconnectedness and trade-offs, and the importance of teamwork. For this professional development opportunity, applicants are sought who have a strong interest and experience in careers in planetary exploration, and who are science and engineering post-docs, recent PhDs, and doctoral students, and faculty teaching such students. Disciplines include planetary science, geoscience, geophysics, environmental science, aerospace engineering, mechanical engineering, and materials science. Participants are selected through a competitive review process, with selections based on the strength of the application and advisor's recommendation letter. Under the mentorship of a lead engineer (Dr. Charles Budney), students select, design, and develop a mission concept in response to the NASA New Frontiers Announcement of Opportunity. They develop their mission in the JPL Advanced Projects Design Team (Team X) environment, which is a cross-functional multidisciplinary team of professional engineers that utilizes concurrent engineering methodologies to complete rapid design, analysis and evaluation of mission concept designs. About 36 students participate each year, divided into two summer sessions. In advance of an intensive week-long session in the Project Design Center at JPL, students select the mission and science goals during a series of six weekly WebEx/telecons, and develop a preliminary suite of instrumentation and a science traceability matrix. Students assume both a science team and a mission development role with JPL Team X mentors. Once at JPL, students participate in a series of Team X project design sessions

  3. The Sulfur Abundance Anomaly in Planetary Nebulae

    CERN Document Server

    Henry, R B C; Kwitter, K B; Milingo, M B

    2006-01-01

    The failure of S and O abundances in most planetary nebulae to display the same strong direct correlation that is observed in extragalactic H II regions represents one of the most perplexing problems in the area of PN abundances today. Galactic chemical evolution models as well as large amounts of observational evidence from H II region studies support the contention that cosmic abundances of alpha elements such as O, Ne, S, Cl, and Ar increase together in lockstep. Yet abundance results from the Henry, Kwitter, & Balick (2004) database show a strong tendency for most PNe to have S abundances that are significantly less than expected from the observed level of O. One reasonable hypothesis for the sulfur anomaly is the past failure to properly measure the abundances of unseen ionization stages above S^+2. Future observations with Spitzer will allow us to test this hypothesis.

  4. Atlas of monochromatic images of planetary nebulae

    CERN Document Server

    Weidmann, W A; Valdarenas, R R Vena; Ahumada, J A; Volpe, M G; Mudrik, A

    2016-01-01

    We present an atlas of more than one hundred original images of planetary nebulae (PNe). These images were taken in a narrow-band filter centred on the nebular emission of the [N II] during several observing campaigns using two moderate-aperture telescopes, at the Complejo Astron\\'omico El Leoncito (CASLEO), and the Estaci\\'on Astrof\\'isica de Bosque Alegre (EABA), both in Argentina. The data provided by this atlas represent one of the most extensive image surveys of PNe in [N II]. We compare the new images with those available in the literature, and briefly describe all cases in which our [N II] images reveal new and interesting structures.

  5. Solar thermal propulsion for planetary spacecraft

    Science.gov (United States)

    Sercel, J. C.

    1985-01-01

    Previous studies have shown that many desirable planetary exploration missions require large injection delta-V. Solar Thermal Rocket (STR) propulsion, under study for orbit-raising applications may enhance or enable such high-energy missions. The required technology of thermal control for liquid hydrogen propellant is available for the required storage duration. Self-deploying, inflatable solar concentrators are under study. The mass penalty for passive cryogenic thermal control, liquid hydrogen tanks and solar concentrators does not compromise the specific impulse advantage afforded by the STR as compared to chemical propulsion systems. An STR injection module is characterized and performance is evaluated by comparison to electric propulsion options for the Saturn Orbiter Titan Probe (SOTP) and Uranus Flyby Uranus Probe (UFUP) missions.

  6. "Planetary Orbit" Systems Composed of Cycloparaphenylenes.

    Science.gov (United States)

    Bachrach, Steven M; Zayat, Zeina-Christina

    2016-06-01

    Cycloparaphenylenes (CPP) can serve as both guest and host in a complex. Geometric analysis indicates that optimal binding occurs when the CPP nanohoops differ by five phenyl rings. Employing C-PCM(THF)/ωB97X-D/6-31G(d) computations, we find that the strongest binding does occur when the host and guest differ by five phenyl rings. The guest CPP is modestly inclined relative to the plane of the host CPP except when the host and guest differ by four phenyl rings, when the inclination angle becomes >40°. The distortion/interaction model shows that interaction dominates and is best when the host and guest differ by five phenyl rings. The computed (1)H NMR shifts of the guest CPP are shifted by about 1 ppm upfield relative to their position when unbound. This distinct chemical shift should aid in experimental detection of these CPP planetary orbit complexes. PMID:27163409

  7. Introducing PLIA: Planetary Laboratory for Image Analysis

    Science.gov (United States)

    Peralta, J.; Hueso, R.; Barrado, N.; Sánchez-Lavega, A.

    2005-08-01

    We present a graphical software tool developed under IDL software to navigate, process and analyze planetary images. The software has a complete Graphical User Interface and is cross-platform. It can also run under the IDL Virtual Machine without the need to own an IDL license. The set of tools included allow image navigation (orientation, centring and automatic limb determination), dynamical and photometric atmospheric measurements (winds and cloud albedos), cylindrical and polar projections, as well as image treatment under several procedures. Being written in IDL, it is modular and easy to modify and grow for adding new capabilities. We show several examples of the software capabilities with Galileo-Venus observations: Image navigation, photometrical corrections, wind profiles obtained by cloud tracking, cylindrical projections and cloud photometric measurements. Acknowledgements: This work has been funded by Spanish MCYT PNAYA2003-03216, fondos FEDER and Grupos UPV 15946/2004. R. Hueso acknowledges a post-doc fellowship from Gobierno Vasco.

  8. Automatic Extraction of Planetary Image Features

    Science.gov (United States)

    Troglio, G.; LeMoigne, J.; Moser, G.; Serpico, S. B.; Benediktsson, J. A.

    2009-01-01

    With the launch of several Lunar missions such as the Lunar Reconnaissance Orbiter (LRO) and Chandrayaan-1, a large amount of Lunar images will be acquired and will need to be analyzed. Although many automatic feature extraction methods have been proposed and utilized for Earth remote sensing images, these methods are not always applicable to Lunar data that often present low contrast and uneven illumination characteristics. In this paper, we propose a new method for the extraction of Lunar features (that can be generalized to other planetary images), based on the combination of several image processing techniques, a watershed segmentation and the generalized Hough Transform. This feature extraction has many applications, among which image registration.

  9. Handbook of cosmic hazards and planetary defense

    CERN Document Server

    Allahdadi, Firooz

    2015-01-01

    Covers in a comprehensive fashion all aspects of cosmic hazards and possible strategies for contending with these threats through a comprehensive planetary defense strategy. This handbook brings together in a single reference work a rich blend of information about the various types of cosmic threats that are posed to human civilization by asteroids, comets, bolides, meteors, solar flares and coronal mass ejections, cosmic radiation and other types of threats that are only recently beginning to be understood and studied, such as investigation of the “cracks” in the protective shield provided by the Van Allen belts and the geomagnetosphere, of matter-antimatter collisions, orbital debris and radiological or biological contamination. Some areas that are addressed involve areas about which there is a good deal of information that has been collected for many decades by multiple space missions run by many different space agencies, observatories and scientific researchers. Other areas involving research and ...

  10. 3D plasma camera for planetary missions

    Science.gov (United States)

    Berthomier, Matthieu; Morel, Xavier; Techer, Jean-Denis

    2014-05-01

    A new 3D field-of-view toroidal space plasma analyzer based on an innovative optical concept allows the coverage of 4π str solid angle with only two sensor heads. It fits the need of all-sky thermal plasma measurements on three-axis stabilized spacecraft which are the most commonly used platforms for planetary missions. The 3D plasma analyzer also takes advantage of the new possibilities offered by the development of an ultra low-power multi-channel charge sensitive amplifier used for the imaging detector of the instrument. We present the design and measured performances of a prototype model that will fly on a test rocket in 2014.

  11. CALCEPH: Planetary ephemeris files access code

    Science.gov (United States)

    Gastineau, M.; Laskar, J.; Manche, H.; Fienga, A.

    2015-05-01

    CALCEPH accesses binary planetary ephemeris files, including INPOPxx, JPL DExxx ,and SPICE ephemeris files. It provides a C Application Programming Interface (API) and, optionally, a Fortran 77 or 2003 interface to be called by the application. Two groups of functions enable the access to the ephemeris files, single file access functions, provided to make transition easier from the JPL functions, such as PLEPH, to this library, and many ephemeris file at the same time. Although computers have different endianess (order in which integers are stored as bytes in computer memory), CALCEPH can handles the binary ephemeris files with any endianess by automatically swaps the bytes when it performs read operations on the ephemeris file.

  12. Mpo - the Bepicolombo Mercury Planetary Orbiter.

    Science.gov (United States)

    Benkhoff, J.

    2008-09-01

    Introduction: BepiColombo is an interdisciplinary mission to explore the planet Mercury through a partnership between ESA and Japan's Aerospace Exploration Agency (JAXA). From their dedicated orbits two spacecrafts, the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO), will be studying the planet and its environment Both orbiter will be launched together on an ARIANE 5. The launch is foreseen for Summer 2014 with arrival in Summer 2020. Solar electric propulsion will be used for the journey to Mercury. In November 2004, the BepiColombo scientific payload has been officially approved. Payload of BepiColombo: The MPO scientific payload comprises eleven instruments/instrument packages; the MMO scientific payload consists of five instruments/instrument packages. Together, the scientific payload of both spacecraft will provide the detailed information necessary to understand Mercury and its magnetospheric environment and to find clues to the origin and evolution of a planet close to its parent star. The MPO will focus on a global characterization of Mercury through the investigation of its interior, surface, exosphere and magnetosphere. In addition, it will be testing Einstein's theory of general relativity. Major effort was put into optimizing the scientific return by defining the payload complement such that individual measurements can be interrelated and complement each other. A detailed overview of the status of BepiColombo will be given with special emphasis on the MPO and its payload complement. BepiColombo factsheet BepiColombo is Europe's first mission to Mercury, the innermost planet of the Solar System, and ESA's first science mission in collaboration with Japan. A satellite 'duo' - consisting of an orbiter for planetary investigation and one for magnetospheric studies - Bepi- Colombo will reach Mercury after a six-year journey towards the inner Solar System, to make the most extensive and detailed study of the planet ever performed

  13. Resonant Removal of Exomoons During Planetary Migration

    CERN Document Server

    Spalding, Christopher; Adams, Fred C

    2015-01-01

    Jupiter and Saturn play host to an impressive array of satellites, making it reasonable to suspect that similar systems of moons might exist around giant extrasolar planets. Furthermore, a significant population of such planets is known to reside at distances of several Astronomical Units (AU), leading to speculation that some moons thereof might support liquid water on their surfaces. However, giant planets are thought to undergo inward migration within their natal protoplanetary disks, suggesting that gas giants currently occupying their host star's habitable zone formed further out. Here we show that when a moon-hosting planet undergoes inward migration, dynamical interactions may naturally destroy the moon through capture into a so-called "evection resonance." Within this resonance, the lunar orbit's eccentricity grows until the moon eventually collides with the planet. Our work suggests that moons orbiting within about 10 planetary radii are susceptible to this mechanism, with the exact number dependent ...

  14. Atlas of monochromatic images of planetary nebulae

    Science.gov (United States)

    Weidmann, W. A.; Schmidt, E. O.; Vena Valdarenas, R. R.; Ahumada, J. A.; Volpe, M. G.; Mudrik, A.

    2016-08-01

    We present an atlas of more than one hundred original images of planetary nebulae (PNe). These images were taken in a narrow-band filter centred on the nebular emission of the [N ii] during several observing campaigns using two moderate-aperture telescopes, at the Complejo Astronómico El Leoncito (CASLEO), and the Estación Astrofísica de Bosque Alegre (EABA), both in Argentina. The data provided by this atlas represent one of the most extensive image surveys of PNe in [N ii]. We compare the new images with those available in the literature, and briefly describe all cases in which our [N ii] images reveal new and interesting structures. The reduced images as FITS files are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A103

  15. Debris disc formation induced by planetary growth

    CERN Document Server

    Kobayashi, Hiroshi

    2014-01-01

    Several hundred stars older than 10 million years have been observed to have infrared excesses. These observations are explained by dust grains formed by the collisional fragmentation of hidden planetesimals. Such dusty planetesimal discs are known as debris discs. In a dynamically cold planetesimal disc, collisional coagulation of planetesimals produces planetary embryos which then stir the surrounding leftover planetesimals. Thus, the collisional fragmentation of planetesimals that results from planet formation forms a debris disc. We aim to determine the properties of the underlying planetesimals in debris discs by numerically modelling the coagulation and fragmentation of planetesimal populations. The brightness and temporal evolution of debris discs depend on the radial distribution of planetesimal discs, the location of their inner and outer edges, their total mass, and the size of planetesimals in the disc. We find that a radially narrow planetesimal disc is most likely to result in a debris disc that ...

  16. Meteorological insights from planetary heat flow measurements

    Science.gov (United States)

    Lorenz, Ralph D.

    2015-04-01

    Planetary heat flow measurements are made with a series of high-precision temperature sensors deployed in a column of regolith to determine the geothermal gradient. Such sensors may, however, be susceptible to other influences, especially on worlds with atmospheres. First, pressure fluctuations at the surface may pump air in and out of pore space leading to observable, and otherwise unexpected, temperature fluctuations at depth. Such pumping is important in subsurface radon and methane transport on Earth: evidence of such pumping may inform understanding of methane or water vapor transport on Mars. Second, the subsurface profile contains a muted record of surface temperature history, and such measurements on other worlds may help constrain the extent to which Earth's Little Ice Age was directly solar-forced, versus volcanic-driven and/or amplified by climate feedbacks.

  17. Research at a European Planetary Simulation Facility

    Science.gov (United States)

    Merrison, Jonathan; Alois, Stefano; Iversen, Jens Jacob

    2016-04-01

    A unique environmental simulation facility will be presented which is capable of re-creating extreme terrestrial or other planetary environments. It is supported by EU activities including a volcanology network VERTIGO and a planetology network Europlanet 2020 RI. It is also used as a test facility by ESA for the forthcoming ExoMars 2018 mission. Specifically it is capable of recreating the key physical parameters such as temperature, pressure (gas composition), wind flow and importantly the suspension/transport of dust or sand particulates. This facility is available both to the scientific and industrial community. Details of this laboratory facility will be presented and some of the most recent activities will be summarized. For information on access to this facility please contact the author.

  18. Scintillation Caustics in Planetary Occultation Light Curves

    CERN Document Server

    Cooray, A R; Cooray, Asantha R.

    2003-01-01

    We revisit the GSC5249-01240 light curve obtained during its occultation by Saturn's North polar region. In addition to refractive scintillations, the power spectrum of intensity fluctuations shows an enhancement of power between refractive and diffractive regimes. We identify this excess power as due to high amplitude spikes in the light curve and suggest that these spikes are due to caustics associated with ray crossing situations. The flux variation in individual spikes follows the expected caustic behavior, including diffraction fringes which we have observed for the first time in a planetary occultation light curve. The presence of caustics in scintillation light curves require an inner scale cut off to the power spectrum of underlying density fluctuations associated with turbulence. Another possibility is the presence of gravity waves in the atmosphere. While occultation light curves previously showed the existence of refractive scintillations, a combination of small projected stellar size and a low rel...

  19. Body contact and body language

    DEFF Research Database (Denmark)

    Winther, Helle Dagmar

    2008-01-01

    and the boundaries between self and world. In western societies, the modern premises for contact are in some ways developing from close contact to virtual communication. With this breadth of perspective in mind, the ques­tion is whether conscious and experimental work with body contact and body language in move......­ment psychology and education provide potential for intense personal develop­ment as well as for social and cultural learning processes. This performative research project originates from the research project entitled, Movement Psy­chol­ogy: The Language of the Body and the Psy­chol­ogy of Movement based...... on the Dance Therapy Form Dansergia. The author, who is a practi­tioner-researcher, is methodologically inspir­ed by phenomenology, performative methods and a narrative and auto-ethnographic approach. The project will be presented in an organic, cre­at­ive and performative way. Through a moving dia...

  20. Scientific field training for human planetary exploration

    Science.gov (United States)

    Lim, D. S. S.; Warman, G. L.; Gernhardt, M. L.; McKay, C. P.; Fong, T.; Marinova, M. M.; Davila, A. F.; Andersen, D.; Brady, A. L.; Cardman, Z.; Cowie, B.; Delaney, M. D.; Fairén, A. G.; Forrest, A. L.; Heaton, J.; Laval, B. E.; Arnold, R.; Nuytten, P.; Osinski, G.; Reay, M.; Reid, D.; Schulze-Makuch, D.; Shepard, R.; Slater, G. F.; Williams, D.

    2010-05-01

    Forthcoming human planetary exploration will require increased scientific return (both in real time and post-mission), longer surface stays, greater geographical coverage, longer and more frequent EVAs, and more operational complexities than during the Apollo missions. As such, there is a need to shift the nature of astronauts' scientific capabilities to something akin to an experienced terrestrial field scientist. To achieve this aim, the authors present a case that astronaut training should include an Apollo-style curriculum based on traditional field school experiences, as well as full immersion in field science programs. Herein we propose four Learning Design Principles (LDPs) focused on optimizing astronaut learning in field science settings. The LDPs are as follows: LDP#1: Provide multiple experiences: varied field science activities will hone astronauts' abilities to adapt to novel scientific opportunities LDP#2: Focus on the learner: fostering intrinsic motivation will orient astronauts towards continuous informal learning and a quest for mastery LDP#3: Provide a relevant experience - the field site: field sites that share features with future planetary missions will increase the likelihood that astronauts will successfully transfer learning LDP#4: Provide a social learning experience - the field science team and their activities: ensuring the field team includes members of varying levels of experience engaged in opportunities for discourse and joint problem solving will facilitate astronauts' abilities to think and perform like a field scientist. The proposed training program focuses on the intellectual and technical aspects of field science, as well as the cognitive manner in which field scientists experience, observe and synthesize their environment. The goal of the latter is to help astronauts develop the thought patterns and mechanics of an effective field scientist, thereby providing a broader base of experience and expertise than could be achieved

  1. Sensor requirements for Earth and planetary observations

    Science.gov (United States)

    Chahine, Moustafa T.

    1990-01-01

    Future generations of Earth and planetary remote sensing instruments will require extensive developments of new long-wave and very long-wave infrared detectors. The upcoming NASA Earth Observing System (EOS) will carry a suite of instruments to monitor a wide range of atmospheric and surface parameters with an unprecedented degree of accuracy for a period of 10 to 15 years. These instruments will observe Earth over a wide spectral range extending from the visible to nearly 17 micrometers with a moderate to high spectral and spacial resolution. In addition to expected improvements in communication bandwidth and both ground and on-board computing power, these new sensor systems will need large two-dimensional detector arrays. Such arrays exist for visible wavelengths and, to a lesser extent, for short wavelength infrared systems. The most dramatic need is for new Long Wavelength Infrared (LWIR) and Very Long Wavelength Infrared (VLWIR) detector technologies that are compatible with area array readout devices and can operate in the temperature range supported by long life, low power refrigerators. A scientific need for radiometric and calibration accuracies approaching 1 percent translates into a requirement for detectors with excellent linearity, stability and insensitivity to operating conditions and space radiation. Current examples of the kind of scientific missions these new thermal IR detectors would enhance in the future include instruments for Earth science such as Orbital Volcanological Observations (OVO), Atmospheric Infrared Sounder (AIRS), Moderate Resolution Imaging Spectrometer (MODIS), and Spectroscopy in the Atmosphere using Far Infrared Emission (SAFIRE). Planetary exploration missions such as Cassini also provide examples of instrument concepts that could be enhanced by new IR detector technologies.

  2. Probing Planetary Formation and Evolution Through Occultations

    Science.gov (United States)

    Rodriguez, Joseph E.; KELT Team

    2016-01-01

    The circumstellar environments of young stellar objects (YSOs) involve complex dynamical interactions between dust and gas that directly influence the formation of planets. However, our understanding of the evolution from the material in the circumstellar disk to the thousands of planetary systems discovered to date, is limited. One means to better constrain the size, mass, and composition of this planet-forming material is to observe a YSO being eclipsed by its circumstellar disk. Through this dissertation project, we are discovering and characterizing both disk eclipsing systems and exoplanets using the Kilodegree Extremely Little Telescope (KELT) project. KELT is a photometric survey for transiting planets orbiting bright stars (8 < V < 11); such bright planet host targets are well-suited for atmospheric characterization of the planets. KELT has discovered 15 planets transiting stars brighter than V ~11 to date. I will present some of the recently discovered planets from the survey and discuss their potential to advance our understanding of planetary atmospheres. In addition, KELT provides photometric monitoring of ~3 million stars, presenting the opportunity to perform multi-year studies of stellar variability generally and rare disk occultations specifically. Using time-series photometry from KELT we are conducting the Disk Eclipse Search with KELT (DESK) survey to look for disk eclipsing events, specifically in young stellar associations. To date, the survey has discovered and analyzed four previously unknown large dimming events around the stars RW Aurigae, V409 Tau, AA Tau, and TYC 2505-672-1, the latter now representing the longest-period eclipsing object known (period ~ 69 years). I will describe our results for planet atmosphere characterization and for protoplanetary disk structure and composition, and discuss how to search for these kinds of systems in future surveys such as LSST.

  3. Hubble Space Telescope, Wide Field Planetary Camera

    Science.gov (United States)

    1981-01-01

    This illustration is a diagram of the Hubble Space Telescope's (HST's), Wide Field Planetary Camera (WF/PC), one of the five Scientific Instruments. The WF/PC uses a four-sided pyramid mirror to split a light image into quarters. It then focuses each quadrant onto one of two sets of four sensors. The sensors are charge-coupled detectors and function as the electronic equivalent of extremely sensitive photographic plates. The WF/PC operates in two modes. The Wide-Field mode that will view 7.2-arcmin sections of the sky, and the Planetary mode that will look at narrower fields of view, such as planets or areas within other galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors.

  4. Mars, Moon, Mercury: Magnetometry Constrains Planetary Evolution

    Science.gov (United States)

    Connerney, John E. P.

    2015-04-01

    We have long appreciated that magnetic measurements obtained about a magnetized planet are of great value in probing the deep interior. The existence of a substantial planetary magnetic field implies dynamo action requiring an electrically conducting, fluid core in convective motion and a source of energy to maintain it. Application of the well-known Lowe's spectrum may in some cases identify the dynamo outer radius; where secular variation can be measured, the outer radius can be estimated using the frozen flux approximation. Magnetic induction may be used to probe the electrical conductivity of the mantle and crust. These are useful constraints that together with gravity and/or other observables we may infer the state of the interior and gain insight into planetary evolution. But only recently has it become clear that space magnetometry can do much more, particularly about a planet that once sustained a dynamo that has since disappeared. Mars is the best example of this class: the Mars Global Surveyor spacecraft globally mapped a remanent crustal field left behind after the demise of the dynamo. This map is a magnetic record of the planet's evolution. I will argue that this map may be interpreted to constrain the era of dynamo activity within Mars; to establish the reversal history of the Mars dynamo; to infer the magnetization intensity of Mars crustal rock and the depth of the magnetized crustal layer; and to establish that plate tectonics is not unique to planet Earth, as has so often been claimed. The Lunar magnetic record is in contrast one of weakly magnetized and scattered sources, not easily interpreted as yet in terms of the interior. Magnetometry about Mercury is more difficult to interpret owing to the relatively weak field and proximity to the sun, but MESSENGER (and ultimately Beppi Columbo) may yet map crustal anomalies (induced and/or remanent).

  5. Body counter

    International Nuclear Information System (INIS)

    The paper gives a survey on some applications of the whole body counter in clinical practice and a critical study of its application as a routine testing method. Remarks on the necessary precautions are followed by a more detailed discussion of the determination of the natural potassium content, the iron metabolism, the vitamin B12 test, investigations of the metabolism of the bone using 47Ca and 85Sr, investigations with iodine and iodine-labelled substances, clearance investigations (in particular the 51Cr EDTA clearance test), as well as the possibilities of neutron activation in vivo. (ORU/AK)

  6. Plasma, magnetic, and electromagnetic measurements at nonmagnetic bodies

    Science.gov (United States)

    Russell, C. T.; Luhmann, J. G.

    1993-01-01

    The need to explore the magnetospheres of the Earth and the giant planets is widely recognized and is an integral part of our planetary exploration program. The equal need to explore the plasma, magnetic, and electromagnetic environments of the nonmagnetic bodies is not so widely appreciated. The previous, albeit incomplete, magnetic and electric field measurements at Venus, Mars, and comets have proven critical to our understanding of their atmospheres and ionospheres in areas ranging from planetary lightning to solar wind scavenging and accretion. In the cases of Venus and Mars, the ionospheres can provide communication paths over the horizon for low-altitude probes and landers, but we know little about their lower boundaries. The expected varying magnetic fields below these planetary ionospheres penetrates the planetary crusts and can be used to sound the electrical conductivity and the thermal profiles of the interiors. However, we have no knowledge of the levels of such fields, let alone their morphology. Finally, we note that the absence of an atmosphere and an ionosphere does not make an object any less interesting for the purposes of electromagnetic exploration. Even weak remanent magnetism such as that found on the Moon during the Apollo program provides insight into the present and past states of planetary interiors. We have very intriguing data from our space probes during times of both close and distant passages of asteroids that suggest they may have coherent magnetization. If true, this observation will put important constraints on how the asteroids formed and have evolved. Our planetary exploration program must exploit its full range of exploration tools if it is to characterize the bodies of the solar system thoroughly. We should especially take advantage of those techniques that are proven and require low mass, low power, and low telemetry rates to undertake.

  7. Planetary Nebulae in Face-On Spiral Galaxies. II. Planetary Nebula Spectroscopy

    CERN Document Server

    Herrmann, Kimberly A

    2009-01-01

    As the second step in our investigation of the mass-to-light ratio of spiral disks, we present the results of a spectroscopic survey of planetary nebulae (PNe) in five nearby, low-inclination galaxies: IC 342, M74 (NGC 628), M83 (NGC 5236), M94 (NGC 4736), and M101 (NGC 5457). Using 50 setups of the WIYN/Hydra and Blanco/Hydra spectrographs, and 25 observations with the Hobby-Eberly Telescope's Medium Resolution Spectrograph, we determine the radial velocities of 99, 102, 162, 127, and 48 PNe, respectively, to a precision better than 15 km/s. Although the main purpose of this data set is to facilitate dynamical mass measurements throughout the inner and outer disks of large spiral galaxies, our spectroscopy has other uses as well. Here, we co-add these spectra to show that to first order, the [O III] and Balmer line ratios of planetary nebulae vary little over the top ~1.5 mag of the planetary nebula luminosity function. The only obvious spectral change occurs with [N II], which increases in strength as one p...

  8. Refined stellar, orbital and planetary parameters of the eccentric HAT-P-2 planetary system

    CERN Document Server

    Pál, András; Torres, Guillermo; Noyes, Robert W; Fischer, Debra A; Johnson, John A; Henry, Gregory W; Butler, R Paul; Marcy, Geoffrey W; Howard, Andrew W; Sipőcz, Brigitta; Latham, David W; Esquerdo, Gilbert A

    2009-01-01

    We present refined parameters for the HAT-P-2(b) extrasolar planetary system (also known as HD 147506(b)), based on new radial velocity and photometric data. HAT-P-2(b) is a transiting extrasolar planet (TEP) that exhibits an eccentric orbit. We present detailed analysis of the planetary and stellar parameters, yielding consistent results of the mass and radius of the star, better constraints on the orbital eccentricity and refined planetary parameters. Namely, the refined stellar parameters are M_star = 1.36 +/- 0.04 M_sun and R_star = 1.64 +0.09 -0.08 R_sun, while the planet has a mass of M_p = 9.09 +/- 0.24 M_Jup and radius of R_p = 1.157 +0.073 -0.092 R_Jup. The refined ephemeris for the planet are E = 2,454,387.49375 +/- 0.00074 (BJD) and P = 5.6334729 +/- 0.0000061 (days) while the newly obtained orbital eccentricity and argument of pericenter are e = 0.5171 +/- 0.0033 and omega = 185.22 +/- 0.95 degs. These orbital elements allow us to predict the timings of secondary eclipses with a reasonable accurac...

  9. Utilizing Science and Technology to Enhance a Future Planetary Mission: Applications to Europa

    Science.gov (United States)

    Bunte, Melissa K.

    A thorough understanding of Europa's geology through the synergy of science and technology, by combining geologic mapping with autonomous onboard processing methods, enhances the science potential of future outer solar system missions. Mapping outlines the current state of knowledge of Europa's surface and near sub-surface, indicates the prevalence of distinctive geologic features, and enables a uniform perspective of formation mechanisms responsible for generating those features. I have produced a global geologic map of Europa at 1:15 million scale and appraised formation scenarios with respect to conditions necessary to produce observed morphologies and variability of those conditions over Europa's visible geologic history. Mapping identifies areas of interest relevant for autonomous study; it serves as an index for change detection and classification and aids pre-encounter targeting. Therefore, determining the detectability of geophysical activity is essential. Activity is evident by the presence of volcanic plumes or outgassing, disrupted surface morphologies, or changes in morphology, color, temperature, or composition; these characteristics reflect important constraints on the interior dynamics and evolutions of planetary bodies. By adapting machine learning and data mining techniques to signatures of plumes, morphology, and spectra, I have successfully demonstrated autonomous rule-based response and detection, identification, and classification of known events and features on outer planetary bodies using the following methods: 1. Edge-detection, which identifies the planetary horizon and highlights features extending beyond the limb; 2. Spectral matching using a superpixel endmember detection algorithm that identifies mean spectral signatures; and 3. Scale invariant feature transforms combined with supervised classification, which examines brightness gradients throughout an image, highlights extreme gradient regions, and classifies those regions based on a

  10. Foreign Body Retrieval

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Foreign Body Retrieval Foreign body retrieval is the removal ... of foreign body detection and removal? What is Foreign Body Retrieval? Foreign body retrieval involves the removal ...

  11. The new Planetary Science Archive: A tool for exploration and discovery of scientific datasets from ESA's planetary missions.

    Science.gov (United States)

    Heather, David; Besse, Sebastien; Barbarisi, Isa; Arviset, Christophe; de Marchi, Guido; Barthelemy, Maud; Docasal, Ruben; Fraga, Diego; Grotheer, Emmanuel; Lim, Tanya; Macfarlane, Alan; Martinez, Santa; Rios, Carlos

    2016-04-01

    Introduction: The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific datasets through various interfaces (e.g. FTP browser, Map based, Advanced search, and Machine interface): http://archives.esac.esa.int/psa All datasets are scientifically peer-reviewed by independent scientists, and are compliant with the Planetary Data System (PDS) standards. Updating the PSA: The PSA is currently implementing a number of significant changes, both to its web-based interface to the scientific community, and to its database structure. The new PSA will be up-to-date with versions 3 and 4 of the PDS standards, as PDS4 will be used for ESA's upcoming ExoMars and BepiColombo missions. The newly designed PSA homepage will provide direct access to scientific datasets via a text search for targets or missions. This will significantly reduce the complexity for users to find their data and will promote one-click access to the datasets. Additionally, the homepage will provide direct access to advanced views and searches of the datasets. Users will have direct access to documentation, information and tools that are relevant to the scientific use of the dataset, including ancillary datasets, Software Interface Specification (SIS) documents, and any tools/help that the PSA team can provide. A login mechanism will provide additional functionalities to the users to aid / ease their searches (e.g. saving queries, managing default views). Queries to the PSA database will be possible either via the homepage (for simple searches of missions or targets), or through a filter menu for more tailored queries. The filter menu will offer multiple options to search for a particular dataset or product, and will manage queries for both in-situ and remote sensing instruments. Parameters such as start-time, phase angle, and heliocentric distance will be emphasized. A further

  12. The new Planetary Science Archive: A tool for exploration and discovery of scientific datasets from ESA's planetary missions

    Science.gov (United States)

    Heather, David

    2016-07-01

    Introduction: The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific datasets through various interfaces (e.g. FTP browser, Map based, Advanced search, and Machine interface): http://archives.esac.esa.int/psa All datasets are scientifically peer-reviewed by independent scientists, and are compliant with the Planetary Data System (PDS) standards. Updating the PSA: The PSA is currently implementing a number of significant changes, both to its web-based interface to the scientific community, and to its database structure. The new PSA will be up-to-date with versions 3 and 4 of the PDS standards, as PDS4 will be used for ESA's upcoming ExoMars and BepiColombo missions. The newly designed PSA homepage will provide direct access to scientific datasets via a text search for targets or missions. This will significantly reduce the complexity for users to find their data and will promote one-click access to the datasets. Additionally, the homepage will provide direct access to advanced views and searches of the datasets. Users will have direct access to documentation, information and tools that are relevant to the scientific use of the dataset, including ancillary datasets, Software Interface Specification (SIS) documents, and any tools/help that the PSA team can provide. A login mechanism will provide additional functionalities to the users to aid / ease their searches (e.g. saving queries, managing default views). Queries to the PSA database will be possible either via the homepage (for simple searches of missions or targets), or through a filter menu for more tailored queries. The filter menu will offer multiple options to search for a particular dataset or product, and will manage queries for both in-situ and remote sensing instruments. Parameters such as start-time, phase angle, and heliocentric distance will be emphasized. A further

  13. NASA Planetary Science Summer School: Preparing the Next Generation of Planetary Mission Leaders

    Science.gov (United States)

    Budney, C. J.; Lowes, L. L.; Sohus, A.; Wheeler, T.; Wessen, A.; Scalice, D.

    2010-12-01

    Sponsored by NASA’s Planetary Science Division, and managed by the Jet Propulsion Laboratory, the Planetary Science Summer School prepares the next generation of engineers and scientists to participate in future solar system exploration missions. Participants learn the mission life cycle, roles of scientists and engineers in a mission environment, mission design interconnectedness and trade-offs, and the importance of teamwork. For this professional development opportunity, applicants are sought who have a strong interest and experience in careers in planetary exploration, and who are science and engineering post-docs, recent PhDs, and doctoral students, and faculty teaching such students. Disciplines include planetary science, geoscience, geophysics, environmental science, aerospace engineering, mechanical engineering, and materials science. Participants are selected through a competitive review process, with selections based on the strength of the application and advisor’s recommendation letter. Under the mentorship of a lead engineer (Dr. Charles Budney), students select, design, and develop a mission concept in response to the NASA New Frontiers Announcement of Opportunity. They develop their mission in the JPL Advanced Projects Design Team (Team X) environment, which is a cross-functional multidisciplinary team of professional engineers that utilizes concurrent engineering methodologies to complete rapid design, analysis and evaluation of mission concept designs. About 36 students participate each year, divided into two summer sessions. In advance of an intensive week-long session in the Project Design Center at JPL, students select the mission and science goals during a series of six weekly WebEx/telecons, and develop a preliminary suite of instrumentation and a science traceability matrix. Students assume both a science team and a mission development role with JPL Team X mentors. Once at JPL, students participate in a series of Team X project design

  14. A general model of resonance capture in planetary systems: First and second order resonances

    CERN Document Server

    Mustill, Alexander J

    2010-01-01

    Mean motion resonances are a common feature of both our own Solar System and of extrasolar planetary systems. Bodies can be trapped in resonance when their orbital semi-major axes change, for instance when they migrate through a protoplanetary disc. We use a Hamiltonian model to thoroughly investigate the capture behaviour for first and second order resonances. Using this method, all resonances of the same order can be described by one equation, with applications to specific resonances by appropriate scaling. We focus on the limit where one body is a massless test particle and the other a massive planet. We quantify how the the probability of capture into a resonance depends on the relative migration rate of the planet and particle, and the particle's eccentricity. Resonant capture fails for high migration rates, and has decreasing probability for higher eccentricities. More massive planets can capture particles at higher eccentricities and migration rates. We also calculate libration amplitudes and the offse...

  15. Hafnium-tungsten chronometry of angrites and the earliest evolution of planetary objects

    DEFF Research Database (Denmark)

    Markowski, A.; Quitté, G.; Kleine, T.;

    2007-01-01

    Angrites are amongst the oldest basalts in the solar system and their origins are enigmatic, some even proposing the planet Mercury as the parent body (APB). Whatever their exact provenance their chronometry provides insights into early stages of planetary melting and differentiation. We present...... various short-lived chronometers provides evidence that Al, Mn and Hf were homogeneously distributed in the solar nebula, although we cannot rule out the possibility of local small heterogeneities. Contrary to recent proposals, the data are also consistent with the previously determined age of the solar...... system based on Pb- Pb systematics of CAIs. The Hf-W data are discussed in the context of two endmember models for the early differentiation of the angrite parent body. In the first model, core formation occurred at 3-4 Ma after CAIs and both groups of angrites formed by two distinct partial melting...

  16. Multi-Robot Planetary Exploration Architectures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space policy direction is shifting, particularly with respect to human goals. Given the uncertainty of future missions to the moon, Mars, and other bodies, a tool...

  17. A radio search for planetary nebulae near the galactic center

    International Nuclear Information System (INIS)

    Because of galactic center is a hostile environment, and because planetaries are weak radio emitters, it is not clear a priori that one expects to detect any planetary nebulae at all in the nuclear region of the Galaxy. Therefore the expected lifetime and flux density distribution of galactic center nebulae is considered. The principal observational results from the Westerbork data, and the results of some pilot observations with the Very Large Array, which were intended to distinguish planetaries from other radio sources on an individual basis are given. (Auth.)

  18. Radioisotope Reduction Using Solar Power for Outer Planetary Missions

    Science.gov (United States)

    Fincannon, James

    2008-01-01

    Radioisotope power systems have historically been (and still are) the power system of choice from a mass and size perspective for outer planetary missions. High demand for and limited availability of radioisotope fuel has made it necessary to investigate alternatives to this option. Low mass, high efficiency solar power systems have the potential for use at low outer planetary temperatures and illumination levels. This paper documents the impacts of using solar power systems instead of radioisotope power for all or part of the power needs of outer planetary spacecraft and illustrates the potential fuel savings of such an approach.

  19. ISO Spectroscopy of Proto-Planetary Nebulae

    Science.gov (United States)

    Hrivnak, Bruce J.

    2000-01-01

    The goal of this program was to determine the chemical properties of the dust shells around protoplanetary nebulae (PPNs) through a study of their short-wavelength (6-45 micron) infrared spectra. PPNs are evolved stars in transition from the asymptotic giant branch to the planetary nebula stages. Spectral features in the 10 to 20 gm region indicate the chemical nature (oxygen- or carbon-rich), and the strengths of the features relate to the physical properties of the shells. A few bright carbon-rich PPNs have been observed to show PAH features and an unidentified 21 micron emission feature. We used the Infrared Space Observatory (ISO) to observe a sample of IRAS sources that have the expected properties of PPNs and for which we have accurate positions. Some of these have optical counterparts (proposal SWSPPN01) and some do not (SWSPPN02). We had previously observed these from the ground with near-infrared photometry and, for those with visible counterparts, visible photometry and spectroscopy, which we have combined with these new ISO data in the interpretation of the spectra. We have completed a study of the unidentified emission feature at 21 micron in eight sources. We find the shape of the feature to be the same in all of the sources, with no evidence of any substructure. The ratio of the emission peak to continuum ranges from 0.13 to 1.30. We have completed a study of seven PPNs and two other carbon-rich objects for which we had obtained ISO 2-45 micron observations. The unidentified emission features at 21 and 30 micron were detected in six sources, including four new detections of the 30 micron feature. This previously unresolved 30 micron feature was resolved and found to consist of a broad feature peaking at 27.2 micron (the "30 micron" feature) and a narrower feature peaking at 25.5 micron (the "26 micron" feature). This new 26 micron feature is detected in eight sources and is particularly strong in IRAS Z02229+6208 and 16594-4656. The unidentified

  20. Emirates Mars Mission Planetary Protection Plan

    Science.gov (United States)

    Awadhi, Mohsen Al

    2016-07-01

    The United Arab Emirates is planning to launch a spacecraft to Mars in 2020 as part of the Emirates Mars Mission (EMM). The EMM spacecraft, Amal, will arrive in early 2021 and enter orbit about Mars. Through a sequence of subsequent maneuvers, the spacecraft will enter a large science orbit and remain there throughout the primary mission. This paper describes the planetary protection plan for the EMM mission. The EMM science orbit, where Amal will conduct the majority of its operations, is very large compared to other Mars orbiters. The nominal orbit has a periapse altitude of 20,000 km, an apoapse altitude of 43,000 km, and an inclination of 25 degrees. From this vantage point, Amal will conduct a series of atmospheric investigations. Since Amal's orbit is very large, the planetary protection plan is to demonstrate a very low probability that the spacecraft will ever encounter Mars' surface or lower atmosphere during the mission. The EMM team has prepared methods to demonstrate that (1) the launch vehicle targets support a 0.01% probability of impacting Mars, or less, within 50 years; (2) the spacecraft has a 1% probability or less of impacting Mars during 20 years; and (3) the spacecraft has a 5% probability or less of impacting Mars during 50 years. The EMM mission design resembles the mission design of many previous missions, differing only in the specific parameters and final destination. The following sequence describes the mission: 1.The mission will launch in July, 2020. The launch includes a brief parking orbit and a direct injection to the interplanetary cruise. The launch targets are specified by the hyperbolic departure's energy C3, and the hyperbolic departure's direction in space, captured by the right ascension and declination of the launch asymptote, RLA and DLA, respectively. The targets of the launch vehicle are biased away from Mars such that there is a 0.01% probability or less that the launch vehicle arrives onto a trajectory that impacts Mars

  1. New Carriers and Sensors for Robotic Planetary Exploration

    Science.gov (United States)

    Romstedt, J.; Schiele, A.; Boudin, N.; Coste, P.; Lindner, R.

    The robotic element of planetary exploration missions does play a crucial role for a successful mission completion. The development of reliable and rugged systems with at the same time low resource requirements and a generous acceptance of harsh environmental conditions is an important constituent of supportive research and development programs. This paper introduces a selection of new technologies developed by ESA support programs to foster the European scientific community and industry. Presented is a focused selection of potential scientific payload carrier modules and its highly integrated scientific instruments designed for in-situ exploration missions to planets and small bodies of our solar system. These developments could serve surface modules with very low resource availability. Low resource requirements and a highly integrated character is an important technology driver of all development plans. The Nanokhod micro-rover is a mobile element capable to explore the surrounding of a stationary lander unit within a radius of 50 meter. Via a tether connection the provision of all communication and power distribution is ensured. The Nanokhod concepts merges the idea of the design of an "as small as possible" mobile element yet keeping the capability to carry a substantial scientific payload suite to analyse the near-by landing site. The engineering model has been build and will undergo a challenging test campaign in the near future. The development of the Geochemistry Instrument Package Facility (GIPF), the payload suite designed for the Nanokhod rover, has been finalized and delivered to ESA. It consists of an Alpha Particle X-ray Spectrometer (APXS), a Mössbauer spectrometer (MIMOS2) and a micro camera (MIROCAM). The instrument front ends have already been thermally qualified at cryogenic temperatures. Beyond a partial heritage from existing flight models all instruments were modified towards an accommodation in the rover's payload cabin and an increased

  2. The "impressionist" force of creation stories in planetary sciences education and outreach

    Science.gov (United States)

    Urban, Z.

    2014-04-01

    Any truly meaningful presentation of a planetary science topic to both pupils/students and the general public should contain three modules. First, there should be all the necessary phenomenology, detailed description of "players" (i.e., planetary bodies and the sources of external influences). Second, there should be similarly complete description of "rules" (i.e., natural forces and factors). Third, one should not forget to provide a "life story", the evolutionary background (i.e., scenarios for origin, development and probable end of relevant planetary bodies). There is nothing new in this basic classification of the material presented to the class or to the general audience. It is a summary of collective wisdom of experienced teachers as well as that of non-teacher scientists engaged in public understanding of science activities. Nevertheless, there is an important caveat in this sequence. The audience could get lost a touch with the topic. This would lead to diminished attention in both the first module (overwhelming by facts and associated numbers) and in the second one (overwhelming by the complexity of interactions). It is suggested that this could be averted by partial inversion of the above working sequence in "emergency situations". For example, if the audience is distracted by some strong influence, like crucial football/ice-hockey match or a fashion display. That means, one should not present the topical material strictly in a usual 1-2-3 style (phenomenologycausality-evolution) but in modified 3-1-2-3 style (evolution-phenomenology-causality-evolution). Of course, a very natural question arises here: Is it possible, at all, to talk or write about evolution without presenting known facts and causes and effects involved beforehand? The answer, based on a large number of trial-and-error efforts, now seems to be: Yes, it is. One should take a lesson from great painters of the second half of the 19th century who have started and then pursued systematically

  3. Gravitational bending of light by planetary multipoles and its measurement with microarcsecond astronomical interferometers

    International Nuclear Information System (INIS)

    General-relativistic deflection of light by mass, dipole, and quadrupole moments of the gravitational field of a moving massive planet in the solar system is derived in the approximation of the linearized Einstein equations. All terms of order 1 μas are taken into account, parametrized, and classified in accordance with their physical origin. The monopolar light-ray deflection, modulated by the radial Doppler effect, is associated with the total mass and radial velocity of the gravitating body. It displaces the apparent positions of stars in the sky plane radially away from the origin of the celestial coordinates associated with the planet. The dipolar deflection of light is due to a translational mismatch of the center of mass of the planet and the origin of the planetary coordinates caused by the inaccuracy of planetary ephemeris. It can also originate from the difference between the null cone for light and that for gravity that is not allowed in general relativity but can exist in some of the alternative theories of gravity. The dipolar gravity field pulls the apparent position of a star in the plane of the sky in both radial and orthoradial directions with respect to the origin of the coordinates. The quadrupolar deflection of light is caused by the physical oblateness, J2, of the planet, but in any practical experiment it will have an admixture of the translation-dependent quadrupole due to inaccuracy of planetary ephemeris. This leads to a bias in the estimated value of J2 that should be minimized by applying an iterative data reduction method designed to disentangle the different multipole moments and to fit out the translation-dependent dipolar and quadrupolar components of light deflection. The method of microarcsecond interferometric astrometry has the potential of greatly improving the planetary ephemerides, getting unbiased measurements of planetary quadrupoles, and of thoroughly testing the null-cone structure of the gravitational field and the speed

  4. Theoretical models of planetary system formation: mass vs. semi-major axis

    Science.gov (United States)

    Alibert, Y.; Carron, F.; Fortier, A.; Pfyffer, S.; Benz, W.; Mordasini, C.; Swoboda, D.

    2013-10-01

    Context. Planet formation models have been developed during the past years to try to reproduce what has been observed of both the solar system and the extrasolar planets. Some of these models have partially succeeded, but they focus on massive planets and, for the sake of simplicity, exclude planets belonging to planetary systems. However, more and more planets are now found in planetary systems. This tendency, which is a result of radial velocity, transit, and direct imaging surveys, seems to be even more pronounced for low-mass planets. These new observations require improving planet formation models, including new physics, and considering the formation of systems. Aims: In a recent series of papers, we have presented some improvements in the physics of our models, focussing in particular on the internal structure of forming planets, and on the computation of the excitation state of planetesimals and their resulting accretion rate. In this paper, we focus on the concurrent effect of the formation of more than one planet in the same protoplanetary disc and show the effect, in terms of architecture and composition of this multiplicity. Methods: We used an N-body calculation including collision detection to compute the orbital evolution of a planetary system. Moreover, we describe the effect of competition for accretion of gas and solids, as well as the effect of gravitational interactions between planets. Results: We show that the masses and semi-major axes of planets are modified by both the effect of competition and gravitational interactions. We also present the effect of the assumed number of forming planets in the same system (a free parameter of the model), as well as the effect of the inclination and eccentricity damping. We find that the fraction of ejected planets increases from nearly 0 to 8% as we change the number of embryos we seed the system with from 2 to 20 planetary embryos. Moreover, our calculations show that, when considering planets more

  5. Earth and planetary aeolian streaks: A review

    Science.gov (United States)

    Cohen-Zada, Aviv Lee; Blumberg, Dan Gabriel; Maman, Shimrit

    2016-03-01

    Wind streaks are abundant aeolian features that have been observed on planetary surfaces by remote sensing means. They have been widely studied, particularly on Mars and Venus and to a much lesser extent on Earth. In imagery, these streaks appear as elongated features that are easily distinguishable from their surroundings. Geomorphologically, these streaks have, thus far, been interpreted as the presence or absence of small loose particles on the surface, deposited or eroded, respectively, by wind. However, the use of different (optical and radar) remote-sensing tools to study wind streaks has led to uncertain interpretations of these features and has hindered their geomorphological definition. Since wind streaks indicate the prevailing wind direction at the time of their formation, they may be used to map near-surface winds and to estimate atmospheric circulation patterns. The aim of this article is to review the main studies focusing on wind streaks and to present the most up-to-date knowledge on this topic. Moreover, a new perspective for wind streak research is suggested: As 'wind streak' is a collective term for a variety of aeolian features that when viewed from above appear as distinctive albedo surface patterns, we suggest that the term should not be used to refer to a geomorphological feature. Since the definition of wind streaks is constrained to remote sensing rather than to geomorphology and is affected by the inherent biases of remote sensing methods, we suggest that 'wind streaks' should be used as a collective term for aeolian surfaces that are discernable from above as bright and dark patterns due to alterations in the characteristics of the surface or to the presence of bedforms. To better understand the mechanisms, time-frames, climate compatibility of wind streaks and the influences of remote sensing on their appearance, we have compiled a new database containing more than 2,900 Earth wind streaks. A comprehensive study of these Earth wind

  6. Observations and Modeling of Tropical Planetary Atmospheres

    Science.gov (United States)

    Laraia, Anne

    2016-01-01

    This thesis is a comprised of three different projects within the topic of tropical atmospheric dynamics. First, I analyze observations of thermal radiation from Saturn's atmosphere and from them, determine the latitudinal distribution of ammonia vapor near the 1.5-bar pressure level. The most prominent feature of the observations is the high brightness temperature of Saturn's subtropical latitudes on either side of the equator. After comparing the observations to a microwave radiative transfer model, I find that these subtropical bands require very low ammonia relative humidity below the ammonia cloud layer in order to achieve the high brightness temperatures observed. We suggest that these bright subtropical bands represent dry zones created by a meridionally overturning circulation. Second, I use a dry atmospheric general circulation model to study equatorial superrotation in terrestrial atmospheres. A wide range of atmospheres are simulated by varying three parameters: the pole-equator radiative equilibrium temperature contrast, the convective lapse rate, and the planetary rotation rate. A scaling theory is developed that establishes conditions under which superrotation occurs in terrestrial atmospheres. The scaling arguments show that superrotation is favored when the off-equatorial baroclinicity and planetary rotation rates are low. Similarly, superrotation is favored when the convective heating strengthens, which may account for the superrotation seen in extreme global-warming simulations. Third, I use a moist slab-ocean general circulation model to study the impact of a zonally-symmetric continent on the distribution of monsoonal precipitation. I show that adding a hemispheric asymmetry in surface heat capacity is sufficient to cause symmetry breaking in both the spatial and temporal distribution of precipitation. This spatial symmetry breaking can be understood from a large-scale energetic perspective, while the temporal symmetry breaking requires

  7. Understanding Microbial Contributions to Planetary Atmosphere

    Science.gov (United States)

    DesMarais, David J.

    2000-01-01

    Should our search of distant, extrasolar planetary atmospheres encounter evidence of life, that evidence will most likely be the gaseous products of microorganisms. Our biosphere was exclusively microbial for over 80 percent of its history and, even today, microbes strongly influence atmospheric composition. Life's greatest environmental impact arises from its capacity for harvesting energy and creating organic matter. Microorganisms catalyze the equilibration of C, S and transition metal species at temperatures where such reactions can be very slow in the absence of life. Sunlight has been harvested through photosynthesis to create enormous energy reservoirs that exist in the form of coexisting reservoirs of reduced, organic C and S stored in Earth's crust, and highly oxidized species (oxygen, sulfate and ferric iron) stored in the crust, oceans and atmosphere. Our civilization taps that storehouse of energy by burning fossil fuels. As astrobiologists, we identify the chemical consequences of distant biospheres as expressed in the atmospheres of their planets. Our approach must recognize that planets, biospheres and atmospheres evolve and change. For example, a tectonically more active early Earth hosted a thermophilic, non-photosynthetic biosphere and a mildly reducing, carbon dioxide-rich and oxygen-poor atmosphere. Microorganisms acquired energy by consuming hydrogen and sulfide and producing a broad array of reduced C and S gases, most notably, methane. Later, diverse types of bacterial photosynthesis developed that enhanced productivity but were incapable of splitting water to produce oxygen. Later, but still prior to 2.6 billion years ago, oxygenic photosynthesis developed. We can expect to encounter distant biospheres that represent various stages of evolution and that coexist with atmospheres ranging from mildly reducing to oxidizing compositions. Accordinaly, we must be prepared to interpret a broad range of atmospheric compositions, all containing

  8. Validation of the nylon flocked swab for planetary protection applications

    Science.gov (United States)

    Moissl-Eichinger, Christine; Probst, Alexander

    The major issue of planetary protection is to prevent the contamination of extraterrestrial en-vironments by terrestrial biomolecules and life forms. In order not to affect or even to confound future life detection missions on celestial bodies, which are of interest for their chemical and bi-ological evolution, spacecraft are constructed in clean rooms and are subject to severe cleaning processes and microbiological controls before launch. Microbiological assays are used to mea-sure and control the bioburden on spacecraft itself and spacecraft hardware during assembly. The current NASA standard assays have originally been developed for the Viking programme in the 70s. Due to the stringent contamination control constrains of the upcoming ESA Ex-oMars mission, these protocols cannot be used, in particular the application of cotton swabs with wooden applicators is no longer possible. Therefore, cotton swabs will be replaced by the novel nylon flocked swabs. In the study presented here, the nylon flocked swabs were validated for the usage for measuring and controling of the bioburden on spacecraft related surfaces. The absolute recovery efficiency was determined, following the guidelines of USP1223 in preci-sion, accuracy, robustness, specificity, linearity and limit of detection. As a standard surface, stainless steel coupons were used, whereas B. atrophaeus (spores) served as standard microbial strain. Additionally, the nylon flocked swab was used for experiments on different rough and smooth surfaces with seven different Bacillus spores and two different protocols. Further details will be given concerning the new ESA standard swab procedure for the microbial examination of flight hardware and clean rooms to be used for the upcoming ExoMars mission.

  9. Estimation of planetary surface roughness by HF sounder observation

    Science.gov (United States)

    Kobayashi, T.; Ono, T.

    Japanese Martian exploration project "Nozomi" was to carry out several science missions. Plasma Wave Sounder, one of those onboard missions, was an HF sounder to study Martian plasma environment, and Martian surface with the altimetry mode (Oya and Ono, 1998) as well. The altimetry mode observation was studied by means of computer simulations utilizing the KiSS code which had been originally designed to simulate the SELENE Lunar Radar Sounder, a spaceborne HF GPR, based on Kirchhoff approximation theory (Kobayashi, Oya and Ono, 2002). We found an empirical power law for the standard deviation of observed altitudes over Gaussian random rough surfaces: it varies in proportion to the square of the RMS gradient of the surface √{2} hRMS{λ_0, where hRMS and λ_0 are the RMS height of the surface and the correlation distance of the surface, respectively. We applied Geometrical optics to understand this empirical power law, and derived a square power law for the standard deviation of the observed altitude. Our Geometrical optics model assumed the followings: 1) the observed surface is a Gaussian random rough surface, 2) the mean surface is a flat horizontal plane, 3) the observed surface echo is the back scattering echoes, 4) the observed altitude is the mean value of the apparent range of those back scattering echoes. These results imply that HF sounder may be utilized to measure the surface roughness of planetary bodies in terms of the RMS gradient of the surface. Refrence: H. Oya and T. Ono, A new altimeter for Mars land shape observations utilizing the ionospheric sounder system onboard the Planet-B spacecraft, Earth Planets Space, Vol. 50, pp.229-234, 1998 T. Kobayashi, H. Oya, and T. Ono, A-scope analysis of subsurface radar sounding of lunar mare region, Earth Planets Space, Vol. 54, pp.973-982, 2002

  10. The Jupiter System Observer: Exploring the Origins of Planetary Systems

    Science.gov (United States)

    Prockter, Louise; Senske, D.; Collins, G. C.; Cooper, J. F.; Hendrix, A.; Hibbitts, C.; Kivelson, M.; Schubert, G.; Showman, A.; Turtle, E.; Williams, D.

    2007-10-01

    The Jupiter System Observer (JSO) is one of four studies commissioned by NASA's Science Mission Directorate to examine the potential science return from a flagship-class mission to the outer solar system. JSO is a long-duration mission that will study the entire Jupiter system, focusing on both its individual components, including Jupiter's atmosphere, rocky and icy moons, rings, and magnetospheric phenomena, and the interactions between them. The wealth of data to be returned by JSO will enable a fuller understanding of a variety of magnetospheric, atmospheric, and geological processes, and will illuminate the question of how planetary systems form and evolve. The science team has outlined a number of significant science goals that can be accomplished by a spacecraft that tours the Jovian system for several years before ultimately ending up in Ganymede orbit. Ganymede was selected as the final destination for JSO because of its unique place in the Jovian system and the solar system - it is only the third body known to have its own dynamo-generated magnetic field. Ganymede is thought to contain a subsurface ocean and exhibits a surface with a variety of older and younger terrains, making it an excellent target for understanding the formation and evolution of icy satellites. Long-term monitoring of Jupiter's atmosphere and rings, Io's volcanism and torus, and high-resolution flyby imaging of Europa, Callisto and Io will enable an unprecedented study of the Jovian system as a solar system analog, and enables cross-cutting scientific objectives in the fields of atmospheres, geology, magnetospheres, and geophysics.

  11. The Effect of CO on Planetary Haze Formation

    CERN Document Server

    Hörst, Sarah M

    2014-01-01

    Organic haze plays a key role in many planetary processes ranging from influencing the radiation budget of an atmosphere to serving as a source of prebiotic molecules on the surface. Numerous experiments have investigated the aerosols produced by exposing mixtures of N$_{2}$/CH$_{4}$ to a variety of energy sources. However, many N$_{2}$/CH$_{4}$ atmospheres in both our solar system and extrasolar planetary systems also contain CO. We have conducted a series of atmosphere simulation experiments to investigate the effect of CO on formation and particle size of planetary haze analogues for a range of CO mixing ratios using two different energy sources, spark discharge and UV. We find that CO strongly affects both number density and particle size of the aerosols produced in our experiments and indicates that CO may play an important, previously unexplored, role in aerosol chemistry in planetary atmospheres.

  12. Multi-Robot Systems for Subsurface Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a heterogeneous multi-robot team developed as a platform for effective subsurface planetary exploration. State-of-art robotic exploration...

  13. Mars & Multi-Planetary Electrical Environment Spectrum Analyzer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our objective is to develop MENSA as a highly integrated planetary radio and digital spectrum analyzer cubesat payload that can be deployed as a satellite...

  14. The effect of carbon monoxide on planetary haze formation

    International Nuclear Information System (INIS)

    Organic haze plays a key role in many planetary processes ranging from influencing the radiation budget of an atmosphere to serving as a source of prebiotic molecules on the surface. Numerous experiments have investigated the aerosols produced by exposing mixtures of N2/CH4 to a variety of energy sources. However, many N2/CH4 atmospheres in both our solar system and extrasolar planetary systems also contain carbon monoxide (CO). We have conducted a series of atmosphere simulation experiments to investigate the effect of CO on the formation and particle size of planetary haze analogues for a range of CO mixing ratios using two different energy sources, spark discharge and UV. We find that CO strongly affects both number density and particle size of the aerosols produced in our experiments and indicates that CO may play an important, previously unexplored, role in aerosol chemistry in planetary atmospheres.

  15. Planetary Instrument Definition and Development Program (PIDDP) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Results of PIDDP have contributed to the development of flight hardware flown on, or selected for, many of NASA’s planetary missions. The instrument...

  16. Low-Power Wideband Digital Spectrometer for Planetary Science Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop a wideband digital spectrometer to support space-born measurements of planetary atmospheric composition. The spectrometer...

  17. Planetary geometry handbook: Mars positional data, 1990 - 2020, volume 3

    Science.gov (United States)

    Sergeyevsky, A. B.; Snyder, G. C.; Paulson, B. L.; Cunniff, R. A.

    1983-01-01

    Graphical data necessary for the analysis of planetary exploration missions to Mars are presented. Positional and geometric information spanning the time period from 1990 through 2020 is provided. The data and usage are explained.

  18. Vibration signal models for fault diagnosis of planetary gearboxes

    Science.gov (United States)

    Feng, Zhipeng; Zuo, Ming J.

    2012-10-01

    A thorough understanding of the spectral structure of planetary gear system vibration signals is helpful to fault diagnosis of planetary gearboxes. Considering both the amplitude modulation and the frequency modulation effects due to gear damage and periodically time variant working condition, as well as the effect of vibration transfer path, signal models of gear damage for fault diagnosis of planetary gearboxes are given and the spectral characteristics are summarized in closed form. Meanwhile, explicit equations for calculating the characteristic frequency of local and distributed gear fault are deduced. The theoretical derivations are validated using both experimental and industrial signals. According to the theoretical basis derived, manually created local gear damage of different levels and naturally developed gear damage in a planetary gearbox can be detected and located.

  19. Chemical composition of planetary nebulae : Including ISO results

    NARCIS (Netherlands)

    Pottasch, [No Value; Beintema, DA; Salas, JB; Feibelman, WA; Henney, WJ; Franco, J; Martos, M; Pena, M

    2002-01-01

    The method of determining abundances using Infrared Space Observatory spectra is discussed. The results for seven planetary nebula are given. Using these data, a preliminary discussion of their evolution is given.

  20. Design and Simulation Tools for Planetary Atmospheric Entry Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Atmospheric entry is one of the most critical phases of flight during planetary exploration missions. During the design of an entry vehicle, experimental and...

  1. Planetary-Whigs: Optical MEMS-Based Seismometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — During this Phase I, Michigan Aerospace Corporation will adapt the design of an optical MEMS seismometer for lunar and other planetary science instrumentation. The...

  2. In Situ Instrument to Detect Prebiotic Compounds in Planetary Ices

    Science.gov (United States)

    Getty, Stephanie A.; Dworkin, Jason; Glavin, Daniel P.; Southard, Adrian; Balvin, Manuel; Kotecki, Carl; Ferrance, Jerome

    2013-01-01

    The development of an in situ LC-MS instrument for future planetary science missions to icy surfaces that are of high astrobiology and astrochemistry potential will advance our understanding of organics in the solar system.

  3. The effect of carbon monoxide on planetary haze formation

    Energy Technology Data Exchange (ETDEWEB)

    Hörst, S. M.; Tolbert, M. A, E-mail: sarah.horst@colorado.edu [Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO (United States)

    2014-01-20

    Organic haze plays a key role in many planetary processes ranging from influencing the radiation budget of an atmosphere to serving as a source of prebiotic molecules on the surface. Numerous experiments have investigated the aerosols produced by exposing mixtures of N{sub 2}/CH{sub 4} to a variety of energy sources. However, many N{sub 2}/CH{sub 4} atmospheres in both our solar system and extrasolar planetary systems also contain carbon monoxide (CO). We have conducted a series of atmosphere simulation experiments to investigate the effect of CO on the formation and particle size of planetary haze analogues for a range of CO mixing ratios using two different energy sources, spark discharge and UV. We find that CO strongly affects both number density and particle size of the aerosols produced in our experiments and indicates that CO may play an important, previously unexplored, role in aerosol chemistry in planetary atmospheres.

  4. One-Meter Class Drilling for Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Robotic planetary exploration missions will need to perform in-situ analysis of rock and/or regolith samples or returning samples back to earth. Obtaining and...

  5. Adaptive bio-inspired navigation for planetary exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Exploration of planetary environments with current robotic technologies relies on human control and power-hungry active sensors to perform even the most elementary...

  6. Adaptive bio-inspired navigation for planetary exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface exploration of planetary environments with current robotic technologies relies heavily on human control and power-hungry active sensors to perform even the...

  7. Highly Efficient Compact Laser for Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to the solicitation for advances in critical components of instruments for enhanced scientific investigations on future planetary mission, Q-Peak...

  8. Equation of state experiments and theory relevant to planetary modelling

    International Nuclear Information System (INIS)

    In recent years there have been a number of static and shockwave experiments on the properties of planetary materials. The highest pressure measurements, and the ones most relevant to planetary modelling, have been obtained by shock compression. Of particular interest to the Jovian group are results for H2, H2O, CH4 and NH3. Although the properties of metallic hydrogen have not been measured, they have been the subject of extensive calculations. In addition recent shock wave experiments on iron report to have detected melting under Earth core conditions. From this data theoretical models have been developed for computing the equations of state of materials used in planetary studies. A compelling feature that has followed from the use of improved material properties is a simplification in the planetary models. (author)

  9. The Conservation Principles and Kepler's Laws of Planetary Motion

    Science.gov (United States)

    Motz, Lloyd

    1975-01-01

    Derives Kepler's three laws of planetary motion algebraically from conservation principles without introducing Newton's law of force explicitly. This procedure can be presented to students who have had no more than high school algebra. (Author)

  10. Novel Polymer Microfluidics Technology for In Situ Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Los Gatos Research proposes to develop a new polymer based microfluidics technology for NASA planetary science applications. In particular, we will design, build...

  11. Nonlinear time heteronymous damping in nonlinear parametric planetary systems

    Czech Academy of Sciences Publication Activity Database

    Hortel, Milan; Škuderová, Alena

    2014-01-01

    Roč. 225, č. 7 (2014), s. 2059-2073. ISSN 0001-5970 Institutional support: RVO:61388998 Keywords : nonlinear dynamics * planetary systems * heteronymous damping Subject RIV: JT - Propulsion, Motors ; Fuels Impact factor: 1.465, year: 2014

  12. Planetary Space Weather Services for the Europlanet 2020 Research Infrastructure

    Science.gov (United States)

    André, Nicolas; Grande, Manuel

    2016-04-01

    Under Horizon 2020, the Europlanet 2020 Research Infrastructure (EPN2020-RI) will include an entirely new Virtual Access Service, WP5 VA1 "Planetary Space Weather Services" (PSWS) that will extend the concepts of space weather and space situational awareness to other planets in our Solar System and in particular to spacecraft that voyage through it. VA1 will make five entirely new 'toolkits' accessible to the research community and to industrial partners planning for space missions: a general planetary space weather toolkit, as well as three toolkits dedicated to the following key planetary environments: Mars (in support ExoMars), comets (building on the expected success of the ESA Rosetta mission), and outer planets (in preparation for the ESA JUICE mission to be launched in 2022). This will give the European planetary science community new methods, interfaces, functionalities and/or plugins dedicated to planetary space weather in the tools and models available within the partner institutes. It will also create a novel event-diary toolkit aiming at predicting and detecting planetary events like meteor showers and impacts. A variety of tools (in the form of web applications, standalone software, or numerical models in various degrees of implementation) are available for tracing propagation of planetary and/or solar events through the Solar System and modelling the response of the planetary environment (surfaces, atmospheres, ionospheres, and magnetospheres) to those events. But these tools were not originally designed for planetary event prediction and space weather applications. So WP10 JRA4 "Planetary Space Weather Services" (PSWS) will provide the additional research and tailoring required to apply them for these purposes. The overall objectives of this Joint Research Aactivities will be to review, test, improve and adapt methods and tools available within the partner institutes in order to make prototype planetary event and space weather services operational in

  13. Molecular Dications in Planetary Atmospheric Escape

    Directory of Open Access Journals (Sweden)

    Stefano Falcinelli

    2016-08-01

    Full Text Available Fundamental properties of multiply charged molecular ions, such as energetics, structure, stability, lifetime and fragmentation dynamics, are relevant to understand and model the behavior of gaseous plasmas as well as ionosphere and astrophysical environments. Experimental determinations of the Kinetic Energy Released (KER for ions originating from dissociations reactions, induced by Coulomb explosion of doubly charged molecular ions (molecular dications produced by double photoionization of CO2, N2O and C2H2 molecules of interest in planetary atmospheres, are reported. The KER measurement as a function of the ultraviolet (UV photon energy in the range of 28–65 eV was extracted from the electron-ion-ion coincidence spectra obtained by using tunable synchrotron radiation coupled with ion imaging techniques at the ELETTRA Synchrotron Light Laboratory Trieste, Italy. These experiments, coupled with a computational analysis based on a Monte Carlo trajectory simulation, allow assessing the probability of escape for simple ionic species in the upper atmosphere of Mars, Venus and Titan. The measured KER in the case of H+, C+, CH+, CH2+, N+, O+, CO+, N2+ and NO+ fragment ions range between 1.0 and 5.5 eV, being large enough to allow these ionic species to participate in the atmospheric escape from such planets into space. In the case of Mars, we suggest a possible explanation for the observed behavior of the O+ and CO22+ ion density profiles.

  14. Characterization of Gravitational Microlensing Planetary Host Stars

    CERN Document Server

    Bennett, D P; Gaudi, B S; Bennett, David P.; Anderson, Jay

    2006-01-01

    The gravitational microlensing light curves that reveal the presence of extrasolar planets generally yield the planet-star mass ratio and separation in units of the Einstein ring radius. The microlensing method does not require the detection of light from the planetary host star. This allows the detection of planets orbiting very faint stars, but it also makes it difficult to convert the planet-star mass ratio to a value for the planet mass. We show that in many cases, the lens stars are readily detectable with high resolution space-based follow-up observations. When the lens star is detected, the lens-source relative proper motion can also be measured, and this allows the masses of the planet and its host star to be determined and the star-planet separation can be converted to physical units.For the recently detected super-Earth planet, OGLE-2005-BLG-169Lb, we show that the lens star will definitely be detectable with observations by the Hubble Space Telescope (HST) unless it is a stellar remnant. Finally, w...

  15. ExoMars planetary protection implementation

    Science.gov (United States)

    Wall, R.; Waugh, L.; Draper, C.; Roe, M.; Pillinger, C.; Pillinger, J.

    ExoMars will be Europe s first Rover mission to the Red Planet The major aim of ExoMars is the search for evidence of extant or extinct life and as such demands the highest level of Planetary Protection PP requirements This presentation will give the latest status of the PP implementation for this Category IVc mission Areas that will be described include - PP strategy for all mission elements Carrier Descent Module Rover and Payloads - Organic contamination control - Bioburden management - Non-nominal impact provisions - AIV options and baseline strategy - Supplier and subcontractor management One of the major activities is the definition of the AIV approach for ExoMars This definition relies heavily on the confident identification of the sterilization vulnerabilities of all hardware and equipment A robust managerial and technical approach is necessary to ensure reliable sterilization compliance information is obtained A suitable approach is also necessary to ensure that no organic contamination will compromise ExoMars scientific results This will require an aseptic build for at least part of the ExoMars assembly and detailed design solutions The presentation of the activities described in this abstract is subject to award of contract by the European Space Agency

  16. Lunar and planetary cartography in Russia

    CERN Document Server

    Shevchenko, Vladislav; Michael, Gregory

    2016-01-01

    This book is the first to document in depth the history of lunar and planetary cartography in Russia. The first map of the far side of the Moon was made with the participation of Lomonosov Moscow University (Sternberg Astronomical Institute, MSU) in 1960. The developed mapping technologies were then used in preparing the “Complete Map of the Moon” in 1967 as well as other maps and globes. Over the years, various maps of Mars have emerged from the special course “Mapping of extraterrestrial objects” in the MSU Geography Department, including the hypsometric map of Mars at a scale of 1:26,000,000, compiled by J.A. Ilyukhina and published in 2004 in an edition of 5,000 copies. A more detailed version of this map has since been produced with a new hypsometric scale. In addition, maps of the northern and southern hemispheres of Mars have been compiled for the hypsometric globe of Mars.  Relief maps of Venus were made in 2008, 2010, and 2011, and hypsometric maps of Phobos and Deimos at a scale of 1:60,000...

  17. The Distance Scale of Planetary Nebulae

    CERN Document Server

    Bensby, T

    2001-01-01

    By collecting distances from the literature, a set of 73 planetary nebulae with mean distances of high accuracy is derived. This sample is used for recalibration of the mass-radius relationship, used by many statistical distance methods. An attempt to correct for a statistical peculiarity, where errors in the distances influences the mass--radius relationship by increasing its slope, has been made for the first time. Distances to PNe in the Galactic Bulge, derived by this new method as well as other statistical methods from the last decade, are then used for the evaluation of these methods as distance indicators. In order of achieving a Bulge sample that is free from outliers we derive new criteria for Bulge membership. These criteria are much more stringent than those used hitherto, in the sense that they also discriminate against background objects. By splitting our Bulge sample in two, one with optically thick (small) PNe and one with optically thin (large) PNe, we find that our calibration is of higher ac...

  18. FITTING PHOTOIONIZATION MODELS TO PLANETARY NEBULAE

    Directory of Open Access Journals (Sweden)

    J. Bohigas

    2009-01-01

    Full Text Available Good to excellent photoionization models based on the Cloudy code were obtained for 13 out of 19 spectra of planetary nebulae. The two most important assumptions are that the photoionizing continuum is a Rauch model star, with gravity set by the condition that the stellar mass must be 1 M , and density is constant and determined from the observed [S II]6717/6731 ratio. The temperature and luminosity of the central star, the inner radius of the nebula and the abundance of carbon are treated as free parameters in each model run, destined to obtain the best possible t to the relative intensities of He II 4686, [O III]5007 and [N II]6584. Observed and modeled nebular temperatures derived from [N II] (6548+6584 /5755 agree within 10%, but models usually underestimate temperatures found from [O III] (4959+5007 /4363, more so when the slit does not cover the in-depth extent of the ionized region. Helium, nitrogen, oxygen, neon, sulfur and argon model abundances are uncertain at the 15%, 15%, 10%, 7%, 30% and 7% level. It is shown that neon abundance in PNe has been consistently overestimated, and an alternative ionization correction factor is recommended.

  19. Radial velocities of Planetary Nebulae revisited

    Science.gov (United States)

    Vázquez, Roberto; Ayala, Sandra A.; Wendolyn Blanco Cárdenas, Mónica; Contreras, María E.; Gómez-Muñoz, Marco Antonio; Guillén, Pedro F.; Olguín, Lorenzo; Ramos-Larios, Gerardo; Sabin, Laurence; Zavala, Saúl A.

    2015-08-01

    We present a new determination of radial velocities of a sample of Galactic Planetary Nebulae (PNe) using a systematic method and the same instrumental setting: the long-slit high-dispersion Manchester Echelle Spectrograph (MES) on the 2.1-m telescope at the San Pedro Mártir Observatory (OAN-SPM; Mexico). This project was inspired by the work of Schneider et al. (1983, A&AS, 52, 399), which has been an important reference during the last decades. Radial velocities of gaseous nebulae can be obtained using the central wavelength of a Gaussian fit, even when there is an expansion velocity, as expected in PNe, but with not enough resolution to see a spectral line splitting. We have used the software SHAPE, a morpho-kinematic modeling and reconstruction tool for astrophysical objects (Steffen et al. 2011, IEEE Trans. Vis. Comput. Graphics, 17, 454), to prove that non-uniform density or brightness, on an expanding shell, can lead to mistaken conclusions about the radial velocity. To determine radial velocities, we only use the spectral data in which a spectral line-splitting is seen, avoiding thus the problem of the possible biased one-Gaussian fit. Cases when this method is not recommended are discussed.This project has been supported by grant PAPIIT-DGAPA-UNAM IN107914. MWB is in grateful receipt of a DGAPA-UNAM postdoctoral scholarship. MAG acknowledges CONACYT for his graduate scholarship.

  20. Kn 26, a New Quadrupolar Planetary Nebula

    CERN Document Server

    Guerrero, Martin A; Ramos-Larios, Gerardo; Vazquez, Roberto

    2013-01-01

    Once classified as an emission line source, the planetary nebula (PN) nature of the source Kn 26 has been only recently recognized in digital sky surveys. To investigate the spectral properties and spatio-kinematical structure of Kn 26, we have obtained high spatial-resolution optical and near-IR narrow-band images, high-dispersion long-slit echelle spectra, and intermediate-resolution spectroscopic observations. The new data reveal an hourglass morphology typical of bipolar PNe. A detailed analysis of its morphology and kinematics discloses the presence of a second pair of bipolar lobes, making Kn 26 a new member of the subclass of quadrupolar PNe. The time-lap between the ejection of the two pairs of bipolar lobes is much smaller than their dynamical ages, implying a rapid change of the preferential direction of the central engine. The chemical composition of Kn 26 is particularly unusual among PNe, with a low N/O ratio (as of type II PNe) and a high helium abundance (as of type I PNe), although not atypica...