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apohele




An asteroid whose orbit lies entirely inside that of Earth. Apoheles form a subgroup of the Aten group. The name – an unofficial one proposed by David Tholen of the University of Hawaii – is Hawaiian for "orbit" and pronounced "ah-poe-hay-lay." Until 2003, the existence of apoheles (like that of vulcanoids), remained hypothetical, although it seemed reasonable to suppose that, on occasions, a near-Earth asteroid would end up as an apohele through successive perturbations by Earth and Venus. Now, however, there are two known apoheles: 2003 CP20 and 2004 JG6. In addition, the 40-m-wide object 1998 DK36, discovered by Tholen and Robert Whiteley in February 1998, may have been an apohele but it was observed on only two consecutive days and subsequently lost due to failure of the observing instrument.

2004 JG6 is particularly interesting in that its orbital period is less than that of Venus, making it the second-closest known object to the Sun, second only to Mercury. 2004 JG6 has an eccentric orbit that crosses the orbits of both Mercury and Venus. It was discovered by Brian A. Skiff if the LONEOS project based at Lowell Observatory.


Related category

   • ASTEROIDS AND OTHER MINOR PLANETS: TYPES AND GROUPS