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P.B. Marty S. Bardeau O. Czoske H. Ebeling J.P. Kneib R. Sadat I. Smail 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(12):2509-2515
We present an analysis of seven clusters observed by XMM-Newton as part of our survey of 17 most X-ray luminous clusters of galaxies at z 0.2 selected for a comprehensive and unbiased study of the mass distribution in massive clusters. Using the public software FTOOLS and XMMSAS we have set up an automated pipeline to reduce the EPIC MOS and pn spectro-imaging data, optimized for extended sources analysis. We also developped a code to perform intensive spectral and imaging analysis particularly focussing on proper background estimate and removal. XMM-Newton deep spectro-imaging of these clusters allowed us to fit a standard β-model to their gas emission profiles as well as a standard MEKAL emission model to their extracted spectra, and test their inferred characteristics against already calibrated relations. 相似文献
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Space Science Reviews - The two isotopes of nitrogen, 14N and 15N, have relative abundances extremely variable among solar system reservoirs such as planets and their atmospheres, primitive and... 相似文献
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E Chassefière J-L Bertaux J-J Berthelier M Cabane V Ciarletti G Durry F Forget M Hamelin F Leblanc M Menvielle M Gerasimov O Korablev S Linkin G Managadze A Jambon G Manhès Ph Lognonné P Agrinier P Cartigny D Giardini T Pike W Kofman A Herique P Coll A Person F Costard Ph Sarda Ph Paillou M Chaussidon B Marty F Robert S Maurice M Blanc C d'Uston J-Ch Sabroux J-F Pineau P Rochette 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(8):1702-1709
In view to prepare Mars human exploration, it is necessary to promote and lead, at the international level, a highly interdisciplinary program, involving specialists of geochemistry, geophysics, atmospheric science, space weather, and biology. The goal of this program will be to elaborate concepts of individual instruments, then of integrated instrumental packages, able to collect exhaustive data sets of environmental parameters from future landers and rovers of Mars, and to favour the conditions of their implementation. Such a program is one of the most urgent need for preparing human exploration, in order to develop mitigation strategies aimed at ensuring the safety of human explorers, and minimizing risk for surface operations. A few main areas of investigation may be listed: particle and radiation environment, chemical composition of atmosphere, meteorology, chemical composition of dust, surface and subsurface material, water in the subsurface, physical properties of the soil, search for an hypothesized microbial activity, characterization of radio-electric properties of the Martian ionosphere. Scientists at the origin of the present paper, already involved at a high degree of responsibility in several Mars missions, and actively preparing in situ instrumentation for future landed platforms (Netlander--now cancelled, MSL-09), express their readiness to participate in both ESA/AURORA and NASA programs of Mars human exploration. They think that the formation of a Mars Environment working group at ESA, in the course of the AURORA definition phase, could act positively in favour of the program, by increasing its scientific cross-section and making it still more focused on human exploration. 相似文献
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Kallenbach R. Robert F. Geiss J. Herbst E. Lammer H. Marty B. Millar T.J. Ott U. Pepin R.O. 《Space Science Reviews》2003,106(1-4):319-376
Volatile isotope abundances are tracers for the evolutionary processes of the solar system. At the same time they carry information
on the galactic nucleosynthetic sources, from which solar matter originates. This working group report summarizes the present
knowledge and addresses unresolved issues regarding fractionation of isotopes of volatile elements in the solar system.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Global Gravity Field Recovery Using Solely GPS Tracking and Accelerometer Data from Champ 总被引:2,自引:0,他引:2
Reigber C. Balmino G. Schwintzer P. Biancale R. Bode A. Lemoine J.-M. König R. Loyer S. Neumayer H. Marty J.-C. Barthelmes F. Perosanz F. Zhu S. Y. 《Space Science Reviews》2003,108(1-2):55-66
A new long-wavelength global gravity field model, called EIGEN-1, has been derived in a joint German-French effort from orbit
perturbations of the CHAMP satellite, exploiting CHAMP-GPS satellite-to-satellite tracking and on-board accelerometer data
over a three months time span. For the first time it becomes possible to recover the gravity field from one satellite only.
Thanks to CHAMP'S tailored orbit characteristics and dedicated instrumentation, providing continuous tracking and on-orbit
measurements of non-gravitational satellite accelerations, the three months CHAMP-only solution provides the geoid and gravity
with an accuracy of 20 cm and 1 mgal, respectively, at a half wavelength resolution of 550 km, which is already an improvement
by a factor of two compared to any pre-CHAMP satellite-only gravity field model.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Becker R.H. Clayton R.N. Galimov E.M. Lammer H. Marty B. Pepin R.O. Wieler R. 《Space Science Reviews》2003,106(1-4):377-410
Variations in the isotopic ratios of volatile elements in different reservoirs on the terrestrial planets carry information
about processes that operated on the planets since their formation. Comparisons between primordial planetary compositions,
to the extent they can be determined, may help us understand the planetary formation process. This working group report summarizes
our knowledge of terrestrial planet volatile inventories.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Stefano Bertone Christophe Le Poncin-Lafitte Pascal Rosenblatt Valéry Lainey Jean-Charles Marty Marie-Christine Angonin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(1):89-96
Accurate tracking of probes is one of the key points of space exploration. Range and Doppler techniques are the most commonly used. In this paper we analyze the impact of the transponder delay, . the processing time between reception and re-emission of a two-way tracking link at the satellite, on tracking observables and on spacecraft orbits. We show that this term, only partially accounted for in the standard formulation of computed space observables, can actually be relevant for future missions with high nominal tracking accuracies or for the re-processing of old missions. We present several applications of our formulation to Earth flybys, the NASA GRAIL and the ESA BepiColombo missions. 相似文献
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