(21861) Maryhedberg Main-belt Asteroid
Discovered on 12 October 1999 by LINEAR at Socorro.
Mary Lucia Hedberg (b. 1991) is a finalist in the 2005 Discovery Channel Young Scientist Challenge (DCYSC), a middle school science competition, for her engineering project. She attends the North Attleboro Middle School, North Attleboro, Massachusetts.Naming citation (20051019/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Maryhedberg is today
Seen from above the solar system on 2026-10-14: Maryhedberg is 2.84 au from the Sun and 3.39 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21861 |
| Provisional designation | 1999 TU189 |
| Orbit class | Main-belt Asteroid |
| Absolute magnitude (H) | 14.45 |
| Orbital period | 5.11 years |
| Semi-major axis | 2.97 au |
| Perihelion – aphelion | 2.82 – 3.11 au |
| Eccentricity | 0.0492 |
| Inclination | 9.46° |
| Closest distance between its orbit and Earth's (MOID) | 1.84 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Mary
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- (5595) Roth
- (6603) Marycragg
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- (7958) Leakey
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- (12627) Maryedwards
- (12628) Acworthorr
- (13412) Guerrieri
All asteroids named after someone called Mary
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