(20504) Magbanua Main-belt Asteroid
Discovered on 7 September 1999 by LINEAR at Socorro.
Mark Jesus Mendoza Magbanua (b. 1971) is a Filipino-American research scientist at the University of California, San Francisco, where he pioneers circulating tumor cell detection. Mark contributes to the identification of comets and active asteroids via the Ruben Comet Catchers project, including observing with the Vatican Advanced Technology Telescope.Naming citation (WGSBN Bull. 6, #11, 24), IAU / Minor Planet Center, via NASA/JPL
Where Magbanua is today
Seen from above the solar system on 2026-10-14: Magbanua is 2.44 au from the Sun and 3.38 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 20504 |
| Provisional designation | 1999 RH15 |
| Orbit class | Main-belt Asteroid |
| Diameter | 4.18 km (#12,306 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.530 |
| Rotation period | 2.25 hours |
| Absolute magnitude (H) | 13.78 |
| Orbital period | 4.08 years |
| Semi-major axis | 2.56 au |
| Perihelion – aphelion | 2.31 – 2.80 au |
| Eccentricity | 0.0952 |
| Inclination | 13.5° |
| Closest distance between its orbit and Earth's (MOID) | 1.32 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Mark
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- (7778) Markrobinson
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- (8686) Akenside
- (8789) Effertz
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- (10598) Markrees
- (12094) Mazumder
- (13211) Stucky
All asteroids named after someone called Mark
Also discovered on 7 September 1999
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- (12588) Arseneau
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- (12924) Madisonicole
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- (14214) Hirsch
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