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351.
SMART-1 after lunar capture: First results and perspectives 总被引:1,自引:0,他引:1
B. H. Foing G. D. Racca A. Marini E. Evrard L. Stagnaro M. Almeida D. Koschny D. Frew J. Zender D. Heather M. Grande J. Huovelin H. U. Keller A. Nathues J. L. Josset A. Malkki W. Schmidt G. Noci R. Birkl L. Iess Z. Sodnik P. McManamon 《Journal of Earth System Science》2005,114(6):689-697
SMART-1 is a technology demonstration mission for deep space solar electrical propulsion and technologies for the future.
SMART-1 is Europe’s first lunar mission and will contribute to developing an international program of lunar exploration. The
spacecraft was launched on 27th September 2003, as an auxiliary passenger to GTO on Ariane 5, to reach the Moon after a 15-month
cruise, with lunar capture on 15th November 2004, just a week before the International Lunar Conference in Udaipur. SMART-1
carries seven experiments, including three remote sensing instruments used during the mission’s nominal six months and one
year extension in lunar science orbit. These instruments will contribute to key planetary scientific questions, related to
theories of lunar origin and evolution, the global and local crustal composition, the search for cold traps at the lunar poles
and the mapping of potential lunar resources 相似文献
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353.
Natural Hazards - Natural hazards such as earthquakes, floods, or wildfires pose a serious threat to road infrastructure. Especially in emergency situations, the society depends on the road... 相似文献
354.
James M. Dohm Victor R. Baker William V. Boynton Alberto G. Fairén Justin C. Ferris Michael Finch Roberto Furfaro Trent M. Hare Daniel M. Janes Jeffrey S. Kargel Suniti Karunatillake John Keller Kris Kerry Kyeong J. Kim Goro Komatsu William C. Mahaney Dirk Schulze-Makuch Lucia Marinangeli Gian G. Ori Javier Ruiz Shawn J. Wheelock 《Planetary and Space Science》2009,57(5-6):664-684
The Gamma Ray Spectrometer (Mars Odyssey spacecraft) has revealed elemental distributions of potassium (K), thorium (Th), and iron (Fe) on Mars that require fractionation of K (and possibly Th and Fe) consistent with aqueous activity. This includes weathering, evolution of soils, and transport, sorting, and deposition, as well as with the location of first-order geomorphological demarcations identified as possible paleoocean boundaries. The element abundances occur in patterns consistent with weathering in situ and possible presence of relict or exhumed paleosols, deposition of weathered materials (salts and clastic minerals), and weathering/transport under neutral to acidic brines. The abundances are explained by hydrogeology consistent with the possibly overlapping alternatives of paleooceans and/or heterogeneous rock compositions from diverse provenances (e.g., differing igneous compositions). 相似文献
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Lynchets are ridges formed by erosion and sediment accumulation downstream of agricultural plots and offer valuable insights into past agricultural activity. These microtopographies cover vast areas and serve as indicators of historical changes in land use. As a result, their ubiquity across Europe makes them particularly interesting. In this study, we propose a geoarchaeological approach to analyze six lynchets, four in the Vosges Mountains and two on the Lorraine Plateau (France). The lynchets can be considered soil archives with no stratigraphic organization or chronological sequence from bottom to top, making it difficult to determine the age of the lynchets and identify changes in land use over time. To this end, we propose the analysis of historical and geo-historical archives combined with the “pedosedimentary” archives of lynchets through charcoal identification and dating combined with near-infrared spectroscopy to determine the age, vegetation, and past land use changes associated with lynchet landscapes. By combining these multiple data sources, we are better able to show the chronological development of these ancient agricultural systems and uncover valuable information on landscape history. Charcoal dating suggests a higher frequency of fires from the Middle Ages. The dating aligns with the regional dynamics of anthropogenic fires, indicating a potential use of fire for cultural purposes. We also demonstrate the difficulty of extrapolating the dating of a lynchet to the entire lynchet system. Our results highlight the difficulties of interpreting the formation and dating of lynchets and the lynchet system on the sole basis of charcoal analysis. However, we highlight the value of applying pedoanthracology to lynchets to determine the dynamics of land use change in former fields. 相似文献