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Apohele asteroids, or alternatively Interior-Earth Objects (IEOs) or Atira asteroids, are a class of near-Earth asteroids.〔 They have not only their perihelion within Earth's orbit, but also their aphelion; that is, their entire orbit is within Earth's (which has a perihelion of 0.983 AU). The first suspected Apohele was , and the first confirmed was 163693 Atira in 2003. , there are 16 suspected Apoheles, of which eight have well-known orbits,〔 of which five have been determined with sufficient precision to receive a permanent number (see list below); 28 more objects have aphelia smaller than Earth's aphelion (1.017 AU). The Near Earth Object Surveillance Satellite is intended to find more. In great part because of the search methods used to look for asteroids, there are currently no known asteroids with orbits contained within Venus or Mercury's (e.g. vulcanoids). There is no standard name for the class. The name ''Apohele'' was proposed by the discoverers of , and is the Hawaiian word for orbit; it was chosen partially because of its similarity to the words ''aphelion (apoapsis)'' and ''helios''. Other authors adopted the designation ''Inner Earth Objects'' (IEOs). Still others, following the general practice to name a new class of asteroids for the first recognized member of that class, use the designation ''Atira asteroids''. Apoheles do not cross Earth's orbit and are not immediate impact threats, but their orbits may be perturbed outward by a close approach to either Mercury or Venus and become Earth-crossing asteroids in the future. ==See also== * List of minor planet groups * Minor planets 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「Apohele asteroid」の詳細全文を読む スポンサード リンク
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