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Geiss J. Bühler F. Cerutti H. Eberhardt P. Filleux Ch. Meister J. Signer P. 《Space Science Reviews》2004,110(3-4):307-335
Space Science Reviews - The Apollo Solar Wind Composition (SWC) experiment was designed to measure elemental and isotopic abundances of the light noble gases in the solar wind, and to investigate... 相似文献
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M.R. Leese J.A.M. McDonnell S.F. Green E. Busoletti B.C. Clark L. Colangeli J.F. Crifo P. Eberhardt F. Giovane E. Grün B. Gustafson D.W. Hughes D. Jackson P. Lamy Y. Langevin I. Mann S. McKenna-Lawlor W.G. Tanner P.R. Weissman J.C. Zarnecki 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,17(12):137-140
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H. Balsiger K. Altwegg P. Bochsler P. Eberhardt J. Fischer S. Graf A. Jäckel E. Kopp U. Langer M. Mildner J. Müller T. Riesen M. Rubin S. Scherer P. Wurz S. Wüthrich E. Arijs S. Delanoye J. De Keyser E. Neefs D. Nevejans H. Rème C. Aoustin C. Mazelle J.-L. Médale J. A. Sauvaud J.-J. Berthelier J.-L. Bertaux L. Duvet J.-M. Illiano S. A. Fuselier A. G. Ghielmetti T. Magoncelli E. G. Shelley A. Korth K. Heerlein H. Lauche S. Livi A. Loose U. Mall B. Wilken F. Gliem B. Fiethe T. I. Gombosi B. Block G. R. Carignan L. A. Fisk J. H. Waite D. T. Young H. Wollnik 《Space Science Reviews》2007,128(1-4):745-801
The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) will answer important questions posed by the mission’s
main objectives. After Giotto, this will be the first time the volatile part of a comet will be analyzed in situ. This is
a very important investigation, as comets, in contrast to meteorites, have maintained most of the volatiles of the solar nebula.
To accomplish the very demanding objectives through all the different phases of the comet’s activity, ROSINA has unprecedented
capabilities including very wide mass range (1 to >300 amu), very high mass resolution (m/Δ m > 3000, i.e. the ability to resolve CO from N2 and 13C from 12CH), very wide dynamic range and high sensitivity, as well as the ability to determine cometary gas velocities, and temperature.
ROSINA consists of two mass spectrometers for neutrals and primary ions with complementary capabilities and a pressure sensor.
To ensure that absolute gas densities can be determined, each mass spectrometer carries a reservoir of a calibrated gas mixture
allowing in-flight calibration. Furthermore, identical flight-spares of all three sensors will serve for detailed analysis
of all relevant parameters, in particular the sensitivities for complex organic molecules and their fragmentation patterns
in our electron bombardment ion sources. 相似文献
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J. Geiss H. Balsiger P. Eberhardt H. P. Walker L. Weber D. T. Young H. Rosenbauer 《Space Science Reviews》1978,22(5):537-566
After one year of operation the GEOS-1 Ion Composition Experiment has surveyed plasma composition at all local times in the L range 3 8 and the energy per charge range from thermal to 16 keV/e. From measurements made in the keV range during eleven magnetic storms we find that the percentage of heavy (M/Q > 1) ions present in the outer magnetosphere increases by a factor of 3 to 10 during disturbances. We conclude that two independent sources (solar wind, characterized by 4He2+, and ionosphere, characterized by O+) give on the average comparable contributions to injected populations, although in a single event one or the other source may dominate. However, in magnetically quiet periods protons are the dominant species with a few percent of heavy ions. With the help of special satellite manoeuvres magnetic field aligned fluxes of 0.05-3 keV/e H+, He+, O+ with traces of O2+ have been observed which may be related to ion beams found previously at lower altitudes in the auroral zone. At still lower energies ( 1 eV/e) the thermal plasma population is found to be made up of six ion species, three of which, D+, He2+ and O2+, were unknown in the magnetosphere prior to the GEOS-1 measurements. We present here a study of the evolution of doubly charged ions and their parent populations over four consecutive days. Various production mechanisms for doubly charged ions are discussed. We argue that ionization of singly charged ions by UV and energetic electrons and protons is the dominant process for plasmasphere production. Furthermore, the observed high concentrations of O2+ at high altitudes are a result of production in the upper ionosphere and plasmasphere combined with upward transport by thermal diffusion. Throughout the 1 year lifetime of GEOS-1 the ICE functioned perfectly and, because of its novel design, a short review of technical performance is included here. 相似文献
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Martin Pätzold Bernd Häusler Kaare Aksnes John D. Anderson Sami W. Asmar Jean-Pierre Barriot Michael K. Bird Hermann Boehnhardt Werner Eidel Eberhardt Grün Wing H. Ip Essam Marouf Trevor Morley Fritz M. Neubauer Hans Rickman Nicolas Thomas Bruce T. Tsurutani Max K. Wallis N. C. Wickramasinghe Eirik Mysen Oystein Olson Stefan Remus Silvia Tellmann Thomas Andert Ludmila Carone Markus Fels Christina Stanzel Iris Audenrieth-Kersten Alexander Gahr Anna-Liane Müller Dusan Stupar Christina Walter 《Space Science Reviews》2007,128(1-4):599-627
The Rosetta spacecraft has been successfully launched on 2nd March 2004 to its new target comet 67 P/Churyumov-Gerasimenko. The science objectives of the Rosetta Radio Science Investigations (RSI) experiment address fundamental aspects of cometary physics such as the mass and bulk density of the nucleus, its gravity field, its interplanetary orbit perturbed by nongravitational forces, its size and shape, its internal structure, the composition and roughness of the nucleus surface, the abundance of large dust grains, the plasma content in the coma and the combined dust and gas mass flux. The masses of two asteroids, Steins and Lutetia, shall be determined during flybys in 2008 and 2010, respectively. Secondary objectives are the radio sounding of the solar corona during the superior conjunctions of the spacecraft with the Sun during the cruise phase. The radio carrier links of the spacecraft Telemetry, Tracking and Command (TT&C) subsystem between the orbiter and the Earth will be used for these investigations. An Ultrastable oscillator (USO) connected to both transponders of the radio subsystem serves as a stable frequency reference source for both radio downlinks at X-band (8.4 GHz) and S-band (2.3 GHz) in the one-way mode. The simultaneous and coherent dual-frequency downlinks via the High Gain Antenna (HGA) permit separation of contributions from the classical Doppler shift and the dispersive media effects caused by the motion of the spacecraft with respect to the Earth and the propagation of the signals through the dispersive media, respectively. The investigation relies on the observation of the phase, amplitude, polarization and propagation times of radio signals transmitted from the spacecraft and received with ground station antennas on Earth. The radio signals are affected by the medium through which the signals propagate (atmospheres, ionospheres, interplanetary medium, solar corona), by the gravitational influence of the planet on the spacecraft and finally by the performance of the various systems involved both on the spacecraft and on ground. 相似文献
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The Neutral Mass Spectrometer on the Giotto spacecraft established that H2O is the dominant species in Comet Halley's volatiles and determined the abundance of more than 10 parent species. The instrument
discovered strong extended H2CO and CO sources in the coma of Comet Halley. Polymerized H2CO associated with the cometary dust and evaporating slowly as the monomer is most likely the extended H2CO source. Photodissociation of the H2CO into CO fully accounts for the extended CO source.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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