Apohele asteroids, or alternatively Interior-Earth Objects (IEOs) or Atira asteroids, are a subclass of Aten 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 1998 DK36, and the first confirmed was (163693) Atira in 2003. As of March 2013, there are 12 suspected Apoheles, of which seven have been observed in multiple oppositions, and the orbits of two have been determined with sufficient precision to receive a permanent number (see list below); 28 more objects have aphelia shorter than the Earth's aphelion (1.017 AU). The Near Earth Object Surveillance Satellite is intended to find more.
There is no standard name for the class. The name Apohele was proposed by the discoverers of 1998 DK36, 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.
Atiras 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.
|# of oppositions
|(164294) 2004 XZ130||0.337||0.618||0.898||0.454||3.0||3|
|1998 DK36||0.405||0.692||0.980||0.416||2.0||1 (1 day)|
|2007 EB26||0.116||0.550||0.980||0.783||8.4||1 (6 days)|
|2010 XB11||0.288||0.618||0.948||0.534||24.8||1 (43 days)|
|2012 VE46||0.454||0.712||0.971||0.362||6.7||1 (37 days)|
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