(20540) Marhalpern Main-belt Asteroid
Discovered on 7 September 1999 by LINEAR at Socorro.
Marcia Halpern mentored a finalist in the 2004 Discovery Channel Youth Science Challenge (DCYSC), a middle school science competition. She teaches at the Muirlands Middle School, La Jolla, California.Naming citation (20041028/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Marhalpern is today
Seen from above the solar system on 2026-10-14: Marhalpern is 2.57 au from the Sun and 2.04 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 20540 |
| Provisional designation | 1999 RV86 |
| Orbit class | Main-belt Asteroid |
| Diameter | 6.92 km (#7,750 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0770 |
| Rotation period | 4.18 hours |
| Absolute magnitude (H) | 14.52 |
| Orbital period | 4.56 years |
| Semi-major axis | 2.75 au |
| Perihelion – aphelion | 2.57 – 2.93 au |
| Eccentricity | 0.0647 |
| Inclination | 5.60° |
| Closest distance between its orbit and Earth's (MOID) | 1.56 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Marcia
All asteroids named after someone called Marcia
Also discovered on 7 September 1999
- (12126) Chersidamas
- (12577) Samra
- (12578) Bensaur
- (12585) Katschwarz
- (12586) Juliaspeyer
- (12588) Arseneau
- (12604) Lisatate
- (12924) Madisonicole
- (13818) Ullery
- (14214) Hirsch
- (15503) Estradioto
- (16067) Brandonfan