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| instruments_list = | insignia = | insignia_caption = | insignia_alt = | insignia_size = }} ''Phoenix'' was a robotic spacecraft on a space exploration mission on Mars under the Mars Scout Program. The ''Phoenix'' lander descended on Mars on May 25, 2008.〔 Mission scientists used instruments aboard the lander to search for environments suitable for microbial life on Mars, and to research the history of water there. The total mission cost was about US $386 million, which includes cost of the launch. The multi-agency program was headed by the Lunar and Planetary Laboratory at the University of Arizona, under the direction of NASA's Jet Propulsion Laboratory. The program was a partnership of universities in the United States, Canada, Switzerland, Denmark, Germany, the United Kingdom, NASA, the Canadian Space Agency, the Finnish Meteorological Institute, Lockheed Martin Space Systems, MacDonald Dettwiler & Associates (MDA) and other aerospace companies. It was the first mission to Mars led by a public university in NASA history.〔(Forbes )〕 It was led directly from the University of Arizona's campus in Tucson, with project management at the Jet Propulsion Laboratory in Pasadena, Calif., and project development at Lockheed Martin in Denver, Colorado. The operational funding for the mission extended through November 10, 2008. ''Phoenix'' was NASA's sixth successful landing out of seven attempts and was the first successful landing in a Martian polar region. The lander completed its mission in August 2008, and made a last brief communication with Earth on November 2 as available solar power dropped with the Martian winter. The mission was declared concluded on November 10, 2008, after engineers were unable to re-contact the craft. After unsuccessful attempts to contact the lander by the Mars Odyssey orbiter up to and past the Martian summer solstice on May 12, 2010, JPL declared the lander to be dead. The program was considered a success because it completed all planned science experiments and observations. ==Program overview== The mission had two goals. One was to study the geologic history of water, the key to unlocking the story of past climate change. The second was to evaluate past or potential planetary habitability in the ice-soil boundary. ''Phoenixs instruments were suitable for uncovering information on the geological and possibly biological history of the Martian Arctic. ''Phoenix'' was the first mission to return data from either of the poles, and contributed to NASA's main strategy for Mars exploration, "''Follow the water.''" The primary mission was anticipated to last 90 sols (Martian days) – just over 92 Earth days. However, the craft exceeded its expected operational lifetime by a little over two months before succumbing to the increasing cold and dark of an advancing Martian winter.〔 Researchers had hoped that the lander would survive into the Martian winter so that it could witness polar ice developing around it – perhaps up to 1 metre of solid carbon dioxide ice could have appeared. Even had it survived some of the winter, the intense cold would have prevented it from lasting all the way through.〔(''Phoenix'' Lander Readied For Mars Exploration ), space.com, Leonard David, February 1, 2007〕 The mission was chosen to be a fixed lander rather than a rover because: * costs were reduced through reuse of earlier equipment (the total mission cost was estimated to be about US $386 million, which includes the launch〔〔〔); * the area of Mars where ''Phoenix'' landed is thought to be relatively uniform and thus traveling is of less value; and * the equipment weight that would be required to allow ''Phoenix'' to travel can instead be dedicated to more and better scientific instruments. The 2003–2004 observations of methane gas on Mars were made remotely by three teams working with separate data. If the methane is truly present in the atmosphere of Mars, then something must be producing it on the planet now, because the gas is broken down by radiation on Mars within 300 years,〔Mumma, M. J.; Novak, R. E.; DiSanti, M. A.; Bonev, B. P., ("A Sensitive Search for Methane on Mars" ) (abstract only). American Astronomical Society, DPS meeting #35, #14.18.〕 therefore the importance to search for biological potential or habitability of the Martian arctic's soils. Methane could also be the product of a geochemical process or the result of volcanic or hydrothermal activity. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Phoenix (spacecraft)」の詳細全文を読む スポンサード リンク
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