(21040) Guntherreitz Main-belt Asteroid
Discovered on 20 July 1990 by E. F. Helin at Palomar.
Günther Reitz (b. 1949) is a German biophysicist who is an internationally-acknowledged leader in space-radiation measurements and dosimetry, and in international collaborative projects on radiation measurements, detection, and protection, such as the world-wide “Matroshka” project. He co-founded and significantly shaped radiobiological research in space.Naming citation (WGSBN Bull. 6, #13, 4), IAU / Minor Planet Center, via NASA/JPL
Where Guntherreitz is today
Seen from above the solar system on 2026-10-14: Guntherreitz is 2.89 au from the Sun and 2.03 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21040 |
| Provisional designation | 1990 OZ |
| Orbit class | Main-belt Asteroid |
| Absolute magnitude (H) | 14.15 |
| Orbital period | 4.39 years |
| Semi-major axis | 2.68 au |
| Perihelion – aphelion | 2.25 – 3.11 au |
| Eccentricity | 0.160 |
| Inclination | 12.8° |
| Closest distance between its orbit and Earth's (MOID) | 1.28 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Gunther
All asteroids named after someone called Gunther