(729) Watsonia Main-belt Asteroid
Discovered on 9 February 1912 by J. H. Metcalf at Winchester.
Where Watsonia is today
Seen from above the solar system on 2026-10-14: Watsonia is 2.63 au from the Sun and 3.31 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 729 |
| Provisional designation | A912 CE |
| Orbit class | Main-belt Asteroid |
| Diameter | 50.0 km (#750 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.133 |
| Rotation period | 25.2 hours |
| Spectral type | STGD |
| Absolute magnitude (H) | 9.55 |
| Orbital period | 4.59 years |
| Semi-major axis | 2.76 au |
| Perihelion – aphelion | 2.50 – 3.03 au |
| Eccentricity | 0.0952 |
| Inclination | 18.1° |
| Closest distance between its orbit and Earth's (MOID) | 1.57 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.