(21663) Banat Main-belt Asteroid
Discovered on 3 September 1999 by Starkenburg at Heppenheim.
The Banat, home of the “Donauschwaben”, is a European region between the Maros river in the north, the Transylvanian Alps in the east, the Danube river in the south and Tisza river in the west. Since the Treaty of Trianon in 1920 the Banat has been divided between western Romania, northern Yugoslavia and eastern Hungary.Naming citation (20021120/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Banat is today
Seen from above the solar system on 2026-10-14: Banat is 2.93 au from the Sun and 2.00 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21663 |
| Provisional designation | 1999 RM |
| Orbit class | Main-belt Asteroid |
| Diameter | 11.2 km (#4,471 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0430 |
| Rotation period | 15.5 hours |
| Absolute magnitude (H) | 14.01 |
| Orbital period | 5.34 years |
| Semi-major axis | 3.06 au |
| Perihelion – aphelion | 2.64 – 3.47 au |
| Eccentricity | 0.135 |
| Inclination | 9.29° |
| Closest distance between its orbit and Earth's (MOID) | 1.64 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.