(509) Iolanda Main-belt Asteroid
Discovered on 28 April 1903 by M. F. Wolf at Heidelberg.
Where Iolanda is today
Seen from above the solar system on 2026-10-14: Iolanda is 3.31 au from the Sun and 4.24 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 509 |
| Provisional designation | A903 HD |
| Orbit class | Main-belt Asteroid |
| Diameter | 51.9 km (#710 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.253 |
| Rotation period | 12.3 hours |
| Spectral type | S |
| Absolute magnitude (H) | 8.39 |
| Orbital period | 5.36 years |
| Semi-major axis | 3.06 au |
| Perihelion – aphelion | 2.76 – 3.36 au |
| Eccentricity | 0.0980 |
| Inclination | 15.4° |
| Closest distance between its orbit and Earth's (MOID) | 1.77 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.