(1866) Sisyphus Apollo
Discovered on 5 December 1972 by P. Wild at Zimmerwald.
Where Sisyphus is today
Seen from above the solar system on 2026-10-14: Sisyphus is 2.43 au from the Sun and 3.35 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 1866 |
| Provisional designation | 1972 XA |
| Orbit class | Apollo · near-Earth |
| Diameter | 8.48 km (#6,162 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.150 |
| Rotation period | 2.40 hours |
| Spectral type | S |
| Absolute magnitude (H) | 12.47 |
| Orbital period | 2.61 years |
| Semi-major axis | 1.89 au |
| Perihelion – aphelion | 0.875 – 2.91 au |
| Eccentricity | 0.538 |
| Inclination | 41.2° |
| Closest distance between its orbit and Earth's (MOID) | 0.103 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.