(20045) Semeniuk Main-belt Asteroid
Discovered on 17 March 1993 by UESAC at La Silla.
Ivan Alexander Semeniuk (b. 1964) is a Canadian science writer who specializes in astronomy and space. Semeniuk studied at the University of Toronto and did a Master's in Science Journalism at Boston University. He was a Knight Fellow at MIT and has worked for the Ontario Science Centre, the Globe & Mail, Nature, New Scientist, and the Discovery Channel.Naming citation (WGSBN Bull. 3, #15, 10), IAU / Minor Planet Center, via NASA/JPL
Where Semeniuk is today
Seen from above the solar system on 2026-10-14: Semeniuk is 2.87 au from the Sun and 3.85 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 20045 |
| Provisional designation | 1993 FV11 |
| Orbit class | Main-belt Asteroid |
| Diameter | 4.09 km (#12,525 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.555 |
| Absolute magnitude (H) | 14.28 |
| Orbital period | 4.14 years |
| Semi-major axis | 2.58 au |
| Perihelion – aphelion | 2.13 – 3.03 au |
| Eccentricity | 0.173 |
| Inclination | 3.67° |
| Closest distance between its orbit and Earth's (MOID) | 1.15 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Ivan
- (5361) Goncharov
- (8244) Mikolaichuk
- (8609) Shuvalov
- (9732) Juchnovski
- (9932) Kopylov
- (11003) Andronov
- (11191) Paskvic
- (12513) Niven
- (17002) Kouzel
- (20654) Ivaneder
- (20658) Bushmarinov
- (22901) Ivanbella
All asteroids named after someone called Ivan
Also discovered on 17 March 1993
- (6795) Ornskoldsvik
- (7705) Humeln
- (8534) Knutsson
- (8540) Ardeberg
- (8695) Bergvall
- (8696) Kjeriksson
- (9617) Grahamchapman
- (9618) Johncleese
- (9619) Terrygilliam
- (9620) Ericidle
- (10123) Fideoja
- (10553) Stenkumla