Apohele asteroid
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 Apophele was 1998 DK36, the first confirmed Apohele was (163693) Atira in 2003. As of March 2010, there are 10 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.
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 1998 DK36,[1] and is the Hawaiian word for orbit; it was chosen partially because of its similarity to the words aphelion (apoapsis) and helios.[2] Other authors adopted the designation Inner Earth Objects (IEOs).[3] Still others, following the general practice to name a new class of asteroids for the first recognized member of that class,[4][5] use the designation Atira asteroids.[6]
[edit] List
List of known and suspected Apoheles as of 12 February 2010.[7]
| Name | Perihelion (AU) |
Semi-major axis (AU) |
Aphelion (AU) |
Eccentricity | Inclination (°) |
Observations (# of oppositions) |
|---|---|---|---|---|---|---|
| 2008 EA32 | 0.428 | 0.616 | 0.804 | 0.305 | 28.3 | 2 |
| (164294) 2004 XZ130 | 0.337 | 0.618 | 0.898 | 0.454 | 3.0 | 3 |
| 2006 WE4 | 0.641 | 0.785 | 0.928 | 0.183 | 24.8 | 2 |
| 2005 TG45 | 0.428 | 0.681 | 0.935 | 0.372 | 23.3 | 3 |
| 2006 KZ39 | 0.292 | 0.616 | 0.939 | 0.525 | 9.4 | 1 (2 days) |
| 2008 UL90 | 0.431 | 0.695 | 0.959 | 0.38 | 24.3 | 2 |
| 2004 JG6 | 0.298 | 0.635 | 0.973 | 0.531 | 18.9 | 2 |
| 1998 DK36 | 0.405 | 0.692 | 0.980 | 0.416 | 2.0 | 1 (1 day) |
| (163693) Atira | 0.502 | 0.741 | 0.980 | 0.322 | 25.6 | 6 |
| 2007 EB26 | 0.119 | 0.550 | 0.980 | 0.783 | 8.4 | 1 (6 days) |
[edit] See also
[edit] References
- ^ Tholen D. J. and Whiteley R. J. (1998). "Results from NEO searches at small solar elongations". Bulletin of the American Astronomical Society 30: 1041.
- ^ http://abob.libs.uga.edu/bobk/ccc/cc070998.html
- ^ Michel P., Zappalà V., Cellino A., and Tanga P. (2000). "Estimated abundances of Atens and asteroids on orbits between Earth and Sun". Icarus 143 (2): 421–424. Bibcode 2000Icar..143..421M. doi:10.1006/icar.1999.6282.
- ^ Wm. Robert Johnston. "Names of Solar System objects and features". http://www.johnstonsarchive.net/astro/names.html. Retrieved 2010-04-03.
- ^ Shoemaker E M (1983). "Asteroid and Comet Bombardment of the Earth". Annual Review of Earth and Planetary Sciences 11: 461–494. Bibcode 1983AREPS..11..461S. doi:10.1146/annurev.ea.11.050183.002333.
- ^ "Near-Earth Object Groups". NASA. http://neo.jpl.nasa.gov/neo/groups.html. Retrieved 2010-04-03.
- ^ "List Of Aten Minor Planets". Minor Planet Center. 02/04/2010. http://www.minorplanetcenter.org/iau/lists/Atensq.html. Retrieved 2010-10-25.
|
||||||||||||||||||||||
