The Arkesilaos family (008[1]) is a small collisional asteroid family of at least 37 known asteroids,[2] named for its largest member, the 22km (14miles)-across asteroid 20961 Arkesilaos. It lies within the larger dynamical group of Jupiter trojans, a group of asteroids in an orbital resonance with Jupiter such that they stay about 60 degrees ahead of/behind the planet in its orbit at all times in the Lagrange points L4 and L5, with the Arkesilaos family being part of the leading cloud around L4, also known as the Greek camp. All members of the family are dark (assumed to be C-type asteroids) with albedos of around 0.06.
An asteroid family is a group of physically related asteroids usually created by a collision with an original larger asteroid, with the fragments continuing on similar orbits to the original. This is distinct from a dynamical group in that the members of a dynamical group only share similar orbits because of gravitational interactions with planets, which concentrate asteroids in a particular orbital range. Members of the Arkesilaos family are both part of the wider Trojan dynamical group, and fragments of 20961 Arkesilaos. The family is considered a catastrophic asteroid family because 20961 Arkesilaos, its largest member, makes up only a fifth of the family's mass.[3]
| Name | Size (km) | proper a (AU) | proper i | |||
|---|---|---|---|---|---|---|
| 11.95 | 22 | 5.2758 | 0.029 | 8.890 | ||
| 12.80 | 15 | 5.2891 | 0.027 | 8.847 | ||
| 12.96 | 14 | 5.2424 | 0.033 | 9.032 | ||
| 13.11 | 13 | 5.2437 | 0.031 | 8.970 | ||
| 13.27 | 13 | 5.2354 | 0.029 | 8.518 | ||
| 13.36 | 13 | 5.2457 | 0.031 | 8.865 | ||
| 13.40 | 11 | 5.2397 | 0.039 | 8.816 | ||
| 13.41 | 11 | 5.2389 | 0.030 | 8.613 | ||
| 13.50 | 11 | 5.2719 | 0.040 | 8.724 | ||
| 13.51 | 11 | 5.2492 | 0.030 | 8.939 |