(11184) Postma Main-belt Asteroid
Discovered on 18 April 1998 by Spacewatch at Kitt Peak.
Sep Postma (1921-1944) was concerned with human rights. He escaped occupied Holland via Spain and was trained in England as an agent for the Special Operations Executive. He parachuted into Holland to organize the Resistance. When caught, he faced the harshest of interrogations.Naming citation (20010902/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Postma is today
Seen from above the solar system on 2026-10-14: Postma is 2.56 au from the Sun and 1.58 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 11184 |
| Provisional designation | 1998 HJ9 |
| Orbit class | Main-belt Asteroid |
| Diameter | 15.3 km (#3,063 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0690 |
| Rotation period | 3.54 hours |
| Absolute magnitude (H) | 12.86 |
| Orbital period | 5.28 years |
| Semi-major axis | 3.03 au |
| Perihelion – aphelion | 2.55 – 3.51 au |
| Eccentricity | 0.158 |
| Inclination | 12.7° |
| Closest distance between its orbit and Earth's (MOID) | 1.56 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also discovered on 18 April 1998
- (11707) Grigery
- (11708) Kathyfries
- (12085) Susanmoore
- (19461) Feingold
- (20321) Lightdonovan
- (20351) Kaborchardt
- (21445) Pegconnolly
- (21446) Tedflint
- (21447) Yungchieh
- (22561) Miviscardi
- (22562) Wage
- (22563) Xinwang