(5209) Oloosson Jupiter Trojan
Discovered on 13 February 1989 by T. Seki at Geisei.
Oloosson, known for its white clay soil, was one of the towns that crewed the forty ships led by Polypoetes as part of the Greek armada.Naming citation (WGSBN Bull. 1, #12, 6), IAU / Minor Planet Center, via NASA/JPL
Where Oloosson is today
Seen from above the solar system on 2026-10-14: Oloosson is 5.45 au from the Sun and 6.39 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 5209 |
| Provisional designation | 1989 CW1 |
| Orbit class | Jupiter Trojan |
| Diameter | 48.2 km (#786 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0690 |
| Rotation period | 14.6 hours |
| Absolute magnitude (H) | 10.31 |
| Orbital period | 11.9 years |
| Semi-major axis | 5.22 au |
| Perihelion – aphelion | 4.95 – 5.49 au |
| Eccentricity | 0.0515 |
| Inclination | 9.03° |
| Closest distance between its orbit and Earth's (MOID) | 3.98 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.