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The ''Europa Multiple-Flyby Mission'' (formerly known as the ''Europa Clipper'') is an interplanetary space probe in development by NASA. Set for a launch in the 2020s, the spacecraft is being developed to study the Galilean moon Europa, through a series of flybys while in orbit around Jupiter. The mission is a follow-up to studies made by the ''Galileo'' spacecraft during its eight years in Jupiter orbit, which indicated the existence of a subsurface ocean underneath Europa. Plans to send a spacecraft to Europa were initially conceived with projects such as ''Europa Orbiter'' and ''Jupiter Icy Moons Orbiter'', in which a spacecraft would be injected into orbit around Europa. However, due to the strong impact of radiation from Jupiter's magnetosphere in Europan orbit, it was decided that it would be safer to inject a spacecraft into an orbit around Jupiter and make several close flybys of the moon instead. The mission was originally branded the ''Europa Clipper'' mission, and began as a joint investigation between the Jet Propulsion Laboratory and the Applied Physics Laboratory. The ''Europa Mission'' spacecraft will be built and manufactured with a scientific payload of nine instruments, contributed by the JPL, APL, Southwest Research Institute, University of Texas, Arizona State University and University of Colorado Boulder. Two possibilities for transfer to Jupiter have been considered: one, using an Atlas V 551 to launch the spacecraft into a trajectory that will make use of multiple gravity assists from Earth and Venus, and the other using the Space Launch System to launch the spacecraft directly towards Jupiter. ==History== Europa has been identified as one of the locations in the Solar System that could possibly harbor microbial extraterrestrial life.〔 Immediately following the Galileo spacecraft's discoveries, JPL conducted preliminary mission studies that envisioned a capable spacecraft such as the Jupiter Icy Moons Orbiter (a $16B mission concept〔(【引用サイトリンク】 title=Project Prometheus final report - page 178 )〕 ), the Jupiter Europa Orbiter (a $4.3B concept), an orbiter ($2B concept), and a multi-flyby spacecraft: Europa Clipper.〔 The proposal and scope of the Europa Clipper mission are still in the conceptual stage, but the approximate cost is estimated at $2 billion.〔〔 Meanwhile, the European Space Agency is already developing the Jupiter Icy Moon Explorer for a proposed launch in 2022.〔(【引用サイトリンク】title=ESA—Selection of the L1 mission )〕 In March 2013, $75 million USD were authorized to expand on the formulation of mission activities, mature the proposed science goals, and fund preliminary instrument development, as suggested in 2011 by the Planetary Science Decadal Survey.〔 In May 2014, a House bill substantially increased Europa Clipper funding budget for the 2014 fiscal year from $15 million to $100 million. The funds would be applied to pre-formulation work. The mission's science definition team is chaired by Louise Prockter from the Johns Hopkins University's the Applied Physics Laboratory (APL), and Barry Goldstein from the Jet Propulsion Laboratory (JPL),〔 who presented an updated concept for Europa Clipper in July 2013. Following the 2014 election cycle, bipartisan support was pledged to continue funding for the Europa Clipper project. The executive branch has also granted such a mission $30 million for preliminary studies, the most the White House has proposed for the mission. In April 2015, NASA offered to the European Space Agency to submit concepts for an additional probe to fly together with the Europa Clipper spacecraft. It could be a simple probe, an impactor or a lander. An internal assessment at ESA is underway to see if there is interest and funds available.〔 In May 2015, NASA announced they had chosen the nine instruments that would fly onboard the orbiter. They will cost about $110 million over the next three years. In June 2015, NASA announced its approval of the mission concept, allowing the orbiter to move to its formulation stage. 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「Europa Multiple-Flyby Mission」の詳細全文を読む スポンサード リンク
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