화성 문제 푸는 중에 들었는데 ... 뒷부분을안읽은듯 ㅜㅜ 마인드 컨트롤이 참 중요해 ...

In one of these studies, a team of Belgian, French, and Japanese researchers offers, for the first time, a complete and coherent scenario for the formation of Phobos and Deimos, which would have been created following a collision between Mars and a primordial body one-third its size, 100 to 800 million years after the beginning of the planet's formation. According to researchers, the debris from this collision formed a very wide disk around Mars, made up of a dense inner part composed of matter in fusion, and a very thin outer part primarily of gas. In the inner part of this disk formed a moon one thousand times the size of Phobos, which has since disappeared. The gravitational interactions created in the outer disk by this massive moon apparently acted as a catalyst for the gathering of debris to form other smaller, more distant moons. After a few thousand years, Mars was surrounded by a group of approximately ten small moons and one enormous moon. A few million years later, once the debris disk had dissipated, the tidal effects of Mars brought most of these satellites back down onto the planet, including the very large moon. Only the two most distant small moons, Phobos and Deimos, remained (see the graphic at the end of the press release).

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