The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform
Jürgen Oberst - One of the best experts on this subject based on the ideXlab platform.
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DePhine – The Deimos and Phobos Interior Explorer
Advances in Space Research, 2018Co-Authors: Jürgen Oberst, Ralph Kahle, Kai Wickhusen, Konrad Willner, Klaus Gwinner, Sofya Spiridonova, Andrew J. Coates, Alain Herique, Dirk Plettemeier, Marina Díaz-michelenaAbstract:Abstract DePhine – Deimos and Phobos Interior Explorer – is a mission proposed in the context of ESA’s Cosmic Vision program, for launch in 2030. The mission will explore the origin and the evolution of the two Martian Satellites, by focusing on their interior structures and diversity, by addressing the following open questions: Are Phobos and Deimos true siblings, originating from the same source and sharing the same formation scenario? Are the Satellites rubble piles or solid bodies? Do they possess hidden deposits of water ice in their interiors? The DePhine spacecraft will be inserted into Mars transfer and will initially enter a Deimos quasi-satellite orbit to carry out a comprehensive global mapping. The goal is to obtain physical parameters and remote sensing data for Deimos comparable to data expected to be available for Phobos at the time of the DePhine mission for comparative studies. As a highlight of the mission, close flybys will be performed at low velocities, which will increase data integration times, enhance the signal strength and data resolution. 10–20 flyby sequences, including polar passes, will result in a dense global grid of observation tracks. The spacecraft orbit will then be changed into a Phobos resonance orbit to carry out multiple close flybys and to perform similar remote sensing as for Deimos. The spacecraft will carry a suite of remote sensing instruments, including a camera system, a radio science experiment, a high-frequency radar, a magnetometer, and a Gamma Ray/Neutron Detector. A steerable antenna will allow simultaneous radio tracking and remote sensing observations (which is technically not possible for Mars Express). Additional instrumentation, e.g. a dust detector and a solar wind sensor, will address further science goals of the mission. If Ariane 6–2 and higher lift performance are available for launch (the baseline mission assumes a launch on a Soyuz Fregat), we expect to have greater spacecraft mobility and possibly added payloads.
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Why Study Phobos and Deimos? An Introduction to the Special Issue
Planetary and Space Science, 2014Co-Authors: Jürgen Oberst, Alexander Zakharov, Rita SchulzAbstract:In 1877, Asaph Hall, an astronomer at the United States Naval Observatory, discovered that Mars is accompanied by two small Satellites, Phobos and Deimos. The two moons have experienced much interest by astronomers and explorers ever since, with their origin being uncertain to the present day. They may have co-accreted with the parent planet, or formed from Martian basin ejecta. Alternatively, they may represent captured primitive asteroids or comets. Space mission planners have identified Phobos and Deimos as targets, from where the recovery of extraterrestrial samples may be comparably straightforward. Also, Phobos has been suggested as a “water-stop” for manned missions to Mars. Phobos is moving deep in the gravity field of Mars, hence, its orbit is a sensitive indicator of various dynamic parameters in the Martian satellite system, which include the Martian gravity field, its temporal variations, as well as shape-, interior structure-, and rotation parameters of Phobos itself. Ultimately, Deimos is expected to escape from its orbit, while Phobos will disrupt from tidal stresses and disintegrate in the Martian atmosphere within time scales of tens of millions years. The mass of Phobos has been determined from radio science data obtained during spacecraft flybys, as well as by modeling of its secular motion. More information on the body׳s interior may be derived from tracking of its rotation and forced librations. Current interior structure modeling suggests that Phobos may be highly porous and to a large extent homogeneous. However, small inhomogeneities, perhaps involving a low-density regolith layer, or mass anomalies associated with the large crater Stickney, cannot be ruled out. Phobos and Deimos are subjected to an intense meteoroid bombardment. Indeed, the surfaces of the Satellites are covered by numerous impact craters, which represent indicators for the source of the meteoroid population and the ages of the Satellites׳ surfaces. It is most puzzling that Phobos appears rather old, in stark contrast to its short remaining lifetime. The meteoroid impacts are known to produce escaping dust, which is predicted to form dust rings within the orbits of Phobos and Deimos. However, no such rings have been detected to the present day. The heavily cratered terrain of Phobos is a unique geologic laboratory. It is cut by systems of grooves, the origins of which are still uncertain more than three decades after their discovery. They may represent chains of secondary craters from Stickney, faulting introduced by tidal stresses and non-synchronous rotation, or impact ejecta from Mars. With Mars Express currently being the only Mars spacecraft to carry out Phobos flybys on a regular basis, a wealth of geoscientific data is accumulating. Geodetic control point networks, shape models, and maps for Phobos are continuously improving, which are essential planning tools for remote sensing and landing site selection of future Phobos missions. Over the past years, astronomers, geophysicists, geologists, cartographers, and planetary explorers from East and West have engaged in several workshops to review our present state of knowledge on the Martian Satellites, and to discuss measurements and observations that are required to further our understanding of the satellite pair. Any progress in our knowledge on the origin, evolution, and characteristics of Phobos and Deimos requires the joint analysis and discussion of all available data. Ultimately, however, new missions to Phobos and Deimos, including sample returns may be needed. This special issue summarizes the workshop contributions and discussions of the team.
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GETEMME—a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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GETEMME: a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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Simulations of meteoroid impacts on Phobosand global crater distributions
2012Co-Authors: V. Dmitriev, V. Lupovka, V. Sizenkov, Jürgen OberstAbstract:Using a data base of 1037 periodic comets, we identified time of activity of potential Martian meteoroid streams. We derived a model of the cumulative particle flux as function of distance from the stream axis. The model allows estimating the probability and velocity of possible meteoroid encounters with Mars and the Martian Satellites and was used for modelling of the current Phobos meteoroid bombardment. The results of stochastic modeling of meteoroid impacts on Phobos are presented.
Volker Klein - One of the best experts on this subject based on the ideXlab platform.
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GETEMME—a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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GETEMME: a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
Christophe Le Poncin-lafitte - One of the best experts on this subject based on the ideXlab platform.
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GETEMME—a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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GETEMME: a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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GETEMME - A Mission to Explore the Martian Satellites and the Limits of Solar System Physics
2012Co-Authors: Jürgen Oberst, V Lainey, Christophe Le Poncin-lafitteAbstract:We propose a mission to Mars and its two Satellites Phobos and Deimos, as part of the ESA COSMIC VISION program. A spacecraft shall deploy retroreflectors on each moon. From Martian equatorial orbit, the spacecraft will carry out laser ranging measurements, which will be analyzed for dynamics of the Martian satellite system and fundamental physics.
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GETEMME: a mission to explore the Martian Satellites
2011Co-Authors: Christophe Le Poncin-lafitte, Valéry Lainey, The Getemme Core TeamAbstract:GETEMME (Gravity, Einstein's Theory, and Exploration of the Martian Moons' Environment) is a proposition of mission towards Martian's moons. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine laser range measurements to the Phobos and Deimos reflectors. Also, asynchronous two-way laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian Satellites system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
Valéry Lainey - One of the best experts on this subject based on the ideXlab platform.
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History of telescopic observations of the Martian Satellites
Planetary and Space Science, 2014Co-Authors: D. Pascu, Stéphane Erard, William Thuillot, Valéry LaineyAbstract:Abstract This article intends to review the different studies of the Mars Satellites Phobos and Deimos realized by means of ground-based telescopic observations as well in the astrometry and dynamics domain as in the physical one. This study spans the first period of investigations of the Martian Satellites since their discovery in 1877 through the astrometry and the spectrometry methods, mainly before the modern period of the space era. It includes also some other observations performed thanks to the Hubble Space Telescope. The different techniques used and the main results obtained for the positionning, the size estimate, the albedo and surface composition are described.
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Martian satellite orbits and ephemerides
Planetary and Space Science, 2014Co-Authors: Robert A. Jacobson, Valéry LaineyAbstract:Abstract We discuss the general characteristics of the orbits of the Martian Satellites, Phobos and Deimos. We provide a concise review of the various descriptions of the orbits by both analytical theories and direct numerical integrations of their equations of motion. After summarizing the observational data used to determine the orbits, we discuss the results of our latest orbits obtained from a least squares fit to the data.
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GETEMME—a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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A New Reduction Of USNO Photographic Plates Of The Martian Satellites
2012Co-Authors: Vincent Robert, D. Pascu, Jean-eudes Arlot, Valéry LaineyAbstract:Thanks to the new technologies, a new astrometric reduction of old photographic plates can provide a better knowledge of the orbital motion of planetary Satellites. In the cadre of the FP7 european project, USNO plates were digitized with the new generation DAMIAN scanning machine. The procedure was applied to various photographic plates and in particular to the USNO photographic plates of the Galilean Satellites. The astrometric results are the most precise. Here we consider a set of a few hundred photographic plates of the Martian Satellites, taken at the USNO, and covering the years 1969-1997. A specific procedure was developed to obtain a high precision and we expect an accuracy better than 100 mas in (RA,Dec) positions of each moon. Since the position of Mars may also be deduced from the observed RA and Dec positions of Phobos and Deimos, we can also assess the accuracy of Mars' ephemeris. First astrometric results will be presented.
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GETEMME: a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
Ralph Kahle - One of the best experts on this subject based on the ideXlab platform.
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DePhine – The Deimos and Phobos Interior Explorer
Advances in Space Research, 2018Co-Authors: Jürgen Oberst, Ralph Kahle, Kai Wickhusen, Konrad Willner, Klaus Gwinner, Sofya Spiridonova, Andrew J. Coates, Alain Herique, Dirk Plettemeier, Marina Díaz-michelenaAbstract:Abstract DePhine – Deimos and Phobos Interior Explorer – is a mission proposed in the context of ESA’s Cosmic Vision program, for launch in 2030. The mission will explore the origin and the evolution of the two Martian Satellites, by focusing on their interior structures and diversity, by addressing the following open questions: Are Phobos and Deimos true siblings, originating from the same source and sharing the same formation scenario? Are the Satellites rubble piles or solid bodies? Do they possess hidden deposits of water ice in their interiors? The DePhine spacecraft will be inserted into Mars transfer and will initially enter a Deimos quasi-satellite orbit to carry out a comprehensive global mapping. The goal is to obtain physical parameters and remote sensing data for Deimos comparable to data expected to be available for Phobos at the time of the DePhine mission for comparative studies. As a highlight of the mission, close flybys will be performed at low velocities, which will increase data integration times, enhance the signal strength and data resolution. 10–20 flyby sequences, including polar passes, will result in a dense global grid of observation tracks. The spacecraft orbit will then be changed into a Phobos resonance orbit to carry out multiple close flybys and to perform similar remote sensing as for Deimos. The spacecraft will carry a suite of remote sensing instruments, including a camera system, a radio science experiment, a high-frequency radar, a magnetometer, and a Gamma Ray/Neutron Detector. A steerable antenna will allow simultaneous radio tracking and remote sensing observations (which is technically not possible for Mars Express). Additional instrumentation, e.g. a dust detector and a solar wind sensor, will address further science goals of the mission. If Ariane 6–2 and higher lift performance are available for launch (the baseline mission assumes a launch on a Soyuz Fregat), we expect to have greater spacecraft mobility and possibly added payloads.
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GETEMME—a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.
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GETEMME: a mission to explore the Martian Satellites and the fundamentals of solar system physics
Experimental Astronomy, 2012Co-Authors: Jürgen Oberst, Valéry Lainey, Christophe Le Poncin-lafitte, Jörn Spurmann, Stephan Ulamec, Jens Biele, Pascal Rosenblatt, Véronique Dehant, Ralph Kahle, Volker KleinAbstract:GETEMME (Gravity, Einstein’s Theory, and Exploration of the Martian Moons’ Environment), a mission which is being proposed in ESA’s Cosmic Vision program, shall be launched for Mars on a Soyuz Fregat in 2020. The spacecraft will initially rendezvous with Phobos and Deimos in order to carry out a comprehensive mapping and characterization of the two Satellites and to deploy passive Laser retro-reflectors on their surfaces. In the second stage of the mission, the spacecraft will be transferred into a lower 1500-km Mars orbit, to carry out routine Laser range measurements to the reflectors on Phobos and Deimos. Also, asynchronous two-way Laser ranging measurements between the spacecraft and stations of the ILRS (International Laser Ranging Service) on Earth are foreseen. An onboard accelerometer will ensure a high accuracy for the spacecraft orbit determination. The inversion of all range and accelerometer data will allow us to determine or improve dramatically on a host of dynamic parameters of the Martian satellite system. From the complex motion and rotation of Phobos and Deimos we will obtain clues on internal structures and the origins of the Satellites. Also, crucial data on the time-varying gravity field of Mars related to climate variation and internal structure will be obtained. Ranging measurements will also be essential to improve on several parameters in fundamental physics, such as the Post-Newtonian parameter β as well as time-rate changes of the gravitational constant and the Lense-Thirring effect. Measurements by GETEMME will firmly embed Mars and its Satellites into the Solar System reference frame.