(9333) Hiraimasa Main-belt Asteroid
Discovered on 15 October 1990 by Endate, K., Watanabe, K. at Kitami.
Masanori Hirai (b. 1943) is a professor at Fukuoka University of Education, specializing in stellar spectroscopic studies of cool stars and, especially, carbon stars. He has demonstrated the existence of polyatomic molecules, HCN and C2H2, in the cool atmospheres of bright carbon stars.Naming citation (20030106/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Hiraimasa is today
Seen from above the solar system on 2026-10-14: Hiraimasa is 2.84 au from the Sun and 3.43 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 9333 |
| Provisional designation | 1990 TK3 |
| Orbit class | Main-belt Asteroid |
| Diameter | 9.65 km (#5,308 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.173 |
| Rotation period | 6.91 hours |
| Absolute magnitude (H) | 12.86 |
| Orbital period | 4.15 years |
| Semi-major axis | 2.58 au |
| Perihelion – aphelion | 2.13 – 3.03 au |
| Eccentricity | 0.176 |
| Inclination | 17.1° |
| Closest distance between its orbit and Earth's (MOID) | 1.13 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Masanori
All asteroids named after someone called Masanori
Also discovered on 15 October 1990
- (5187) Domon
- (5188) Paine
- (6905) Miyazaki
- (6964) Kunihiko
- (8274) Soejima
- (8660) Sano
- (10318) Sumaura
- (10760) Ozeki
- (12706) Tanezaki
- (14395) Tommorgan
- (16503) Ayato
- (19160) Chikayoshitomi