(20996) Pandrosion Inner Main-belt Asteroid
Discovered on 4 August 1986 by E. F. Helin at Palomar.
Pandrosion of Alexandria (fl. 4th century BCE) was a mathematician, believed by many current scholars to have been female. If so, she would be an earlier female contributor to mathematics than Hypatia. Pandrosion is known for having possibly developed an approximate method for doubling the cube.Naming citation (WGSBN Bull. 5, #2, 19), IAU / Minor Planet Center, via NASA/JPL
Where Pandrosion is today
Seen from above the solar system on 2026-10-14: Pandrosion is 1.87 au from the Sun and 1.12 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 20996 |
| Provisional designation | 1986 PB |
| Orbit class | Inner Main-belt Asteroid |
| Diameter | 2.96 km (#15,323 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.320 |
| Rotation period | 43.6 hours |
| Absolute magnitude (H) | 14.96 |
| Orbital period | 2.64 years |
| Semi-major axis | 1.91 au |
| Perihelion – aphelion | 1.82 – 2.01 au |
| Eccentricity | 0.0496 |
| Inclination | 26.8° |
| Closest distance between its orbit and Earth's (MOID) | 0.805 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.