(9689) Freudenthal Main-belt Asteroid
Discovered on 24 September 1960 by van Houten, C. J., van Houten-Groeneveld, I., Gehrels, T. at Palomar.
Hans Freudenthal (1905-1990), a former president of the International Commission on Mathematical Instruction, was known for his effort to reform mathematical education and the didactics used to teach mathematics. He wrote not only about mathematics and astronomy but was also a writer of essays and poems.Naming citation (20010804/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Freudenthal is today
Seen from above the solar system on 2026-10-14: Freudenthal is 2.95 au from the Sun and 3.37 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 9689 |
| Provisional designation | 4831 P-L |
| Orbit class | Main-belt Asteroid |
| Diameter | 3.74 km (#13,347 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.219 |
| Absolute magnitude (H) | 14.58 |
| Orbital period | 4.22 years |
| Semi-major axis | 2.61 au |
| Perihelion – aphelion | 2.21 – 3.01 au |
| Eccentricity | 0.152 |
| Inclination | 13.4° |
| Closest distance between its orbit and Earth's (MOID) | 1.27 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Hans
- (3692) Rickman
- (4991) Hansuess
- (5323) Fogh
- (5475) Hanskennedy
- (6847) Kunz-Hallstein
- (8122) Holbein
- (9562) Memling
- (10542) Ruckers
- (12672) Nygardh
- (12729) Berger
- (13177) Hansschmidt
- (14025) Fallada
All asteroids named after someone called Hans
Also discovered on 24 September 1960
- (1743) Schmidt
- (1744) Harriet
- (1776) Kuiper
- (1777) Gehrels
- (1795) Woltjer
- (1808) Bellerophon
- (1809) Prometheus
- (1810) Epimetheus
- (1811) Bruwer
- (1812) Gilgamesh
- (1846) Bengt
- (1868) Thersites