(12242) Koon Jupiter Trojan
Discovered on 18 August 1988 by Shoemaker, C. S., Shoemaker, E. M. at Palomar.
Koon, a notable fighter, was the eldest son of Antenor. Grieved by the death of his brother Iphidamas at the hands of Agamemnon, he fought and wounded him but was in turn beheaded by Agamemnon.Naming citation (20001013/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Koon is today
Seen from above the solar system on 2026-10-14: Koon is 5.32 au from the Sun and 4.98 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 12242 |
| Provisional designation | 1988 QY |
| Orbit class | Jupiter Trojan |
| Diameter | 37.9 km (#1,035 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0710 |
| Rotation period | 17.0 hours |
| Absolute magnitude (H) | 10.9 |
| Orbital period | 11.6 years |
| Semi-major axis | 5.12 au |
| Perihelion – aphelion | 4.77 – 5.47 au |
| Eccentricity | 0.0680 |
| Inclination | 29.8° |
| Closest distance between its orbit and Earth's (MOID) | 3.91 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also discovered on 18 August 1988
More named asteroids discovered by Shoemaker, C. S., Shoemaker, E. M.
- (3025) Higson
- (3199) Nefertiti
- (3225) Hoag
- (3317) Paris
- (3554) Amun
- (3671) Dionysus
- (3700) Geowilliams
- (3854) George
- (3880) Kaiserman
- (3927) Feliciaplatt
- (3977) Maxine
- (4151) Alanhale
← (12241) Lefort · (12244) Werfel →