(25539) Roberthelm Main-belt Asteroid
Discovered on 8 December 1999 by LINEAR at Socorro.
Robert Helm mentored a finalist in the 2009 Intel Science Talent Search (STS), a science competition for high school seniors. He teaches at the Methacton High School, Norristown, Pennsylvania.Naming citation (20090311/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Roberthelm is today
Seen from above the solar system on 2026-10-14: Roberthelm is 2.63 au from the Sun and 2.77 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 25539 |
| Provisional designation | 1999 XA159 |
| Orbit class | Main-belt Asteroid |
| Diameter | 5.10 km (#10,429 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0980 |
| Absolute magnitude (H) | 14.99 |
| Orbital period | 4.43 years |
| Semi-major axis | 2.70 au |
| Perihelion – aphelion | 2.61 – 2.79 au |
| Eccentricity | 0.0346 |
| Inclination | 6.19° |
| Closest distance between its orbit and Earth's (MOID) | 1.62 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Robert
- (1955) McMath
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- (5477) Holmes
- (5585) Parks
- (5636) Jacobson
- (5739) Robertburns
- (5817) Robertfrazer
All asteroids named after someone called Robert
Also discovered on 8 December 1999
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- (14683) Remy
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- (23096) Mihika
- (23098) Huanghuang
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- (25538) Markcarlson
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