(12951) Koenkuijken Main-belt Asteroid
Discovered on 29 September 1973 by van Houten, C. J., van Houten-Groeneveld, I., Gehrels, T. at Palomar.
Koen Kuijken (b. 1963) is a Belgian-Dutch astronomer, specializing in galaxy dynamics, gravitational lensing and dark matter. From 2007 to 2012 he was scientific director of Leiden Observatory. Koen was principal investigator of the cosmological Kilo-Degree Survey, carried out with ESO’s VLT Survey Telescope.Naming citation (WGSBN Bull. 5, #17, 17), IAU / Minor Planet Center, via NASA/JPL
Where Koenkuijken is today
Seen from above the solar system on 2026-10-14: Koenkuijken is 3.28 au from the Sun and 4.17 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 12951 |
| Provisional designation | 1041 T-2 |
| Orbit class | Main-belt Asteroid |
| Diameter | 5.75 km (#9,293 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.256 |
| Absolute magnitude (H) | 13.61 |
| Orbital period | 5.06 years |
| Semi-major axis | 2.95 au |
| Perihelion – aphelion | 2.60 – 3.29 au |
| Eccentricity | 0.117 |
| Inclination | 2.06° |
| Closest distance between its orbit and Earth's (MOID) | 1.59 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Koen
All asteroids named after someone called Koen
Also discovered on 29 September 1973
- (2049) Grietje
- (4357) Korinthos
- (4549) Burkhardt
- (4721) Atahualpa
- (4752) Myron
- (4876) Strabo
- (4978) Seitz
- (5151) Weerstra
- (5197) Rottmann
- (5243) Clasien
- (5244) Amphilochos
- (5266) Rauch