(39890) Bobstephens Main-belt Asteroid
Discovered on 23 March 1998 by P. Pravec at Ondrejov.
Robert Stephens (b. 1955) is a Californian amateur astronomer who has determined some 30 sets of minor-planet lightcurve parameters since becoming active in the field in 1999. His high-quality work and generosity in sharing his time and knowledge within the amateur community have set a standard for others to follow.Naming citation (20020724/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Bobstephens is today
Seen from above the solar system on 2026-10-14: Bobstephens is 2.73 au from the Sun and 3.36 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 39890 |
| Provisional designation | 1998 FA3 |
| Orbit class | Main-belt Asteroid |
| Rotation period | 9.55 hours |
| Absolute magnitude (H) | 16.26 |
| Orbital period | 4.18 years |
| Semi-major axis | 2.60 au |
| Perihelion – aphelion | 2.04 – 3.15 au |
| Eccentricity | 0.214 |
| Inclination | 5.50° |
| Closest distance between its orbit and Earth's (MOID) | 1.03 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Robert
- (1955) McMath
- (3514) Hooke
- (3875) Staehle
- (4564) Clayton
- (4809) Robertball
- (5109) Robertmiller
- (5308) Hutchison
- (5477) Holmes
- (5585) Parks
- (5636) Jacobson
- (5739) Robertburns
- (5817) Robertfrazer
All asteroids named after someone called Robert
Also discovered on 23 March 1998
- (8958) Stargazer
- (11167) Kunzak
- (11364) Karlstejn
- (11365) NASA
- (20256) Adolfneckar
- (37859) Bobkoff
- (39892) Evaseidlova