The Aten asteroids are a group of near-Earth asteroids, named after the first of the group to be discovered (2062 Aten, discovered January 7 1976 by Eleanor F. Helin). They have semi-major axes of less than one astronomical unit, placing them inside the orbit of Earth.

Nearly all known Aten asteroids have their aphelion greater than one AU. Those that have their aphelion entirely within the Earth's orbit are known as Apohele asteroids. As of May 2004 there are only two known Apoheles: 2003 CP₂₀ and 2004 JG₆.

The smallest semi-major axis is that of (66391) 1999 KW₄, at 0.642 AU (its eccentricity of 0.688 takes it from a perihelion of 0.200 AU —well within Mercury's orbit!— to an aphelion of 1.084 AU), although 2004 JG₆ seems to have an even smaller one (0.635 AU; eccentricity 0.532 ranging from 0.297 to 0.973 AU —enough to cross Venus' orbit but not Mercury's).

The list of Aten asteroids includes:

Name	Year	Discoverer
2004 FH	2004	LINEAR
2000 BD19	2000	LINEAR
(68347) 2001 KB67	2001	LINEAR
(66400) 1999 LT7	1999	LINEAR
(66391) 1999 KW4	1999	LINEAR
(66146) 1998 TU3	1998	LINEAR
(66063) 1998 RO1	1998	LINEAR
(65679) 1989 UQ	1989	Christian Pollas
(33342) 1998 WT24	1998	LINEAR
(5604) 1992 FE	1992	Robert H. McNaught
(5590) 1990 VA	1990	Spacewatch
5381 Sekhmet	1991	Carolyn Shoemaker
3753 Cruithne	1986	J. Duncan Waldron
3554 Amun	1986	Carolyn Shoemaker, Eugene Shoemaker
3362 Khufu	1984	R. Scott Dunbar , Maria A. Barucci
2340 Hathor	1976	Charles T. Kowal
2100 Ra-Shalom	1978	Eleanor F. Helin
2062 Aten	1976	Eleanor F. Helin

External links

• List of Aten Minor Planets