(644) Cosima Main-belt Asteroid
Discovered on 7 September 1907 by A. Kopff at Heidelberg.
Where Cosima is today
Seen from above the solar system on 2026-10-14: Cosima is 2.97 au from the Sun and 3.92 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 644 |
| Provisional designation | A907 RG |
| Orbit class | Main-belt Asteroid |
| Diameter | 17.0 km (#2,674 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.271 |
| Rotation period | 7.56 hours |
| Spectral type | S |
| Absolute magnitude (H) | 10.76 |
| Orbital period | 4.19 years |
| Semi-major axis | 2.60 au |
| Perihelion – aphelion | 2.20 – 3.00 au |
| Eccentricity | 0.155 |
| Inclination | 1.04° |
| Closest distance between its orbit and Earth's (MOID) | 1.20 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.