(21782) Davemcdonald Main-belt Asteroid
Discovered on 8 September 1999 by LONEOS at Anderson Mesa.
Irish amateur astronomer David McDonald (b. 1964) undertakes astrometry of minor planets. He is active in promoting amateur astronomy in Ireland.Naming citation (20080718/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Davemcdonald is today
Seen from above the solar system on 2026-10-14: Davemcdonald is 2.51 au from the Sun and 3.30 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21782 |
| Provisional designation | 1999 RV239 |
| Orbit class | Main-belt Asteroid |
| Diameter | 2.31 km (#16,585 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.330 |
| Rotation period | 2.80 hours |
| Absolute magnitude (H) | 15.42 |
| Orbital period | 3.61 years |
| Semi-major axis | 2.35 au |
| Perihelion – aphelion | 2.01 – 2.70 au |
| Eccentricity | 0.147 |
| Inclination | 5.34° |
| Closest distance between its orbit and Earth's (MOID) | 0.991 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called David
- (2410) Morrison
- (4262) DeVorkin
- (4536) Drewpinsky
- (5270) Kakabadze
- (5332) Davidaguilar
- (5826) Bradstreet
- (5845) Davidbrewster
- (5920) Davidbell
- (5965) Meisel
- (6033) Southwood
- (6111) Davemckay
- (6435) Daveross
All asteroids named after someone called David
Also discovered on 8 September 1999
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- (12581) Rovinj
- (13817) Genobechetti
- (16066) Richardbressler
- (16070) Charops
- (19629) Serra
- (19694) Dunkelman
- (19695) Billnye
- (20544) Kimhansell
- (20545) Karenhowell
- (20546) Michaelfruhauf
- (20547) Michimani