(677) Aaltje Main-belt Asteroid
Discovered on 18 January 1909 by A. Kopff at Heidelberg.
Where Aaltje is today
Seen from above the solar system on 2026-10-14: Aaltje is 2.82 au from the Sun and 3.77 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 677 |
| Provisional designation | A909 BP |
| Orbit class | Main-belt Asteroid |
| Diameter | 32.4 km (#1,259 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.313 |
| Rotation period | 16.6 hours |
| Spectral type | Sl |
| Absolute magnitude (H) | 9.65 |
| Orbital period | 5.08 years |
| Semi-major axis | 2.96 au |
| Perihelion – aphelion | 2.82 – 3.09 au |
| Eccentricity | 0.0459 |
| Inclination | 8.49° |
| Closest distance between its orbit and Earth's (MOID) | 1.84 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.