(3643) Tienchanglin Main-belt Asteroid
Discovered on 29 October 1978 by Purple Mountain Observatory at Nanking.
Chang-lin Tien (b. 1935) was the seventh chancellor of the University of California at Berkeley, serving from 1990 to 1997, and is now the Nippon Electric Company distinguished professor of engineering there. His professional work is mainly in energy, environment and high-tech areas.Naming citation (19990928/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Tienchanglin is today
Seen from above the solar system on 2026-10-14: Tienchanglin is 2.25 au from the Sun and 1.52 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 3643 |
| Provisional designation | 1978 UN2 |
| Orbit class | Main-belt Asteroid |
| Diameter | 9.78 km (#5,242 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.135 |
| Absolute magnitude (H) | 13.05 |
| Orbital period | 3.72 years |
| Semi-major axis | 2.40 au |
| Perihelion – aphelion | 2.04 – 2.76 au |
| Eccentricity | 0.150 |
| Inclination | 13.9° |
| Closest distance between its orbit and Earth's (MOID) | 1.05 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.