(101) Helena Main-belt Asteroid
Discovered on 15 August 1868 by J. C. Watson at Ann Arbor.
👶 Helena as a baby name🐶 Helena as a dog name
Where Helena is today
Seen from above the solar system on 2026-10-14: Helena is 2.34 au from the Sun and 1.35 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 101 |
| Provisional designation | A868 PA |
| Orbit class | Main-belt Asteroid |
| Diameter | 65.8 km (#513 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.190 |
| Rotation period | 23.1 hours |
| Spectral type | S |
| Absolute magnitude (H) | 8.39 |
| Orbital period | 4.15 years |
| Semi-major axis | 2.58 au |
| Perihelion – aphelion | 2.22 – 2.95 au |
| Eccentricity | 0.140 |
| Inclination | 10.2° |
| Closest distance between its orbit and Earth's (MOID) | 1.21 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
More named asteroids discovered by J. C. Watson
- (79) Eurynome
- (93) Minerva
- (94) Aurora
- (100) Hekate
- (103) Hera
- (104) Klymene
- (105) Artemis
- (106) Dione
- (115) Thyra
- (119) Althaea
- (121) Hermione
- (128) Nemesis
← (100) Hekate · (102) Miriam →