(21665) Frege Main-belt Asteroid
Discovered on 5 September 1999 by P. G. Comba at Prescott.
Friedrich Ludwig Gottlob Frege (1848-1925), a professor at Jena, devoted his work to the goal of establishing the logical foundations of arithmetic. He introduced symbols for the concepts---now widely used in logic---of assertion, negation, implication and existential and universal quantifier.Naming citation (20010509/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Frege is today
Seen from above the solar system on 2026-10-14: Frege is 2.22 au from the Sun and 1.86 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21665 |
| Provisional designation | 1999 RR1 |
| Orbit class | Main-belt Asteroid |
| Absolute magnitude (H) | 15.8 |
| Orbital period | 3.42 years |
| Semi-major axis | 2.27 au |
| Perihelion – aphelion | 1.99 – 2.56 au |
| Eccentricity | 0.126 |
| Inclination | 2.87° |
| Closest distance between its orbit and Earth's (MOID) | 0.977 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Friedrich
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- (12694) Schleiermacher
- (13254) Kekule
- (14041) Durrenmatt
All asteroids named after someone called Friedrich
Also discovered on 5 September 1999
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