(30281) Horstman Main-belt Asteroid
Discovered on 24 April 2000 by LONEOS at Anderson Mesa.
Helen Horstman (b. 1936) is a long-time employee of Lowell Observatory, starting in 1964 and retiring in 2007. Helen served as observatory secretary, cataloged images from the Planetary Patrol, and became executive secretary to the director. Since retiring, she has volunteered in the library.Naming citation (MPC batch dated 2017-03-12), IAU / Minor Planet Center, via NASA/JPL
Where Horstman is today
Seen from above the solar system on 2026-10-14: Horstman is 1.91 au from the Sun and 1.18 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 30281 |
| Provisional designation | 2000 HH57 |
| Orbit class | Main-belt Asteroid |
| Diameter | 2.51 km (#16,239 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.326 |
| Absolute magnitude (H) | 14.71 |
| Orbital period | 3.55 years |
| Semi-major axis | 2.33 au |
| Perihelion – aphelion | 1.86 – 2.79 au |
| Eccentricity | 0.200 |
| Inclination | 7.48° |
| Closest distance between its orbit and Earth's (MOID) | 0.864 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
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All asteroids named after someone called Helen
Also discovered on 24 April 2000
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