(7186) Tomioka Main-belt Asteroid
Discovered on 26 December 1991 by Endate, K., Watanabe, K. at Kitami.
Named in honor of Hiroyuki Tomioka (b. 1942), director of weather information in Hitachi City. An amateur astronomer, he is a charter member of the Nippon Meteor Society and has observed meteors for more than 40 years, both visually and photographically. In addition to his observations from Japan, he often visits the Chiro Observatory Southern Station in Australia to observe southern meteor showers. Name proposed by the discoverers following a suggestion by A. Fujii and T. Sato.Naming citation (19981005/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Tomioka is today
Seen from above the solar system on 2026-10-14: Tomioka is 2.60 au from the Sun and 2.47 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 7186 |
| Provisional designation | 1991 YF |
| Orbit class | Main-belt Asteroid |
| Diameter | 13.3 km (#3,593 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0690 |
| Rotation period | 7.31 hours |
| Absolute magnitude (H) | 13.14 |
| Orbital period | 3.66 years |
| Semi-major axis | 2.38 au |
| Perihelion – aphelion | 2.05 – 2.71 au |
| Eccentricity | 0.138 |
| Inclination | 9.26° |
| Closest distance between its orbit and Earth's (MOID) | 1.07 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Hiroyuki
- (9642) Takatahiro
- (11072) Hiraoka
- (11928) Akimotohiro
- (19392) Oyamada
- (27816) Naitohiroyuki
- (30925) Todahiroyuki
- (31402) Negishi
- (46649) Tsudahiroyuki
All asteroids named after someone called Hiroyuki