(8400) Tomizo Main-belt Asteroid
Discovered on 4 January 1994 by T. Kobayashi at Oizumi.
Okamoto Tomizo (b. 1933) joined the Tokyo Astronomical Observatory in 1954 to observe the solar corona and flare phenomenon at the Norikura Solar Observatory. After his 1994 retirement, he helped popularize astronomy as a member of the Public Information Office at the National Astronomical Observatory of Japan.Naming citation (20040306/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Tomizo is today
Seen from above the solar system on 2026-10-14: Tomizo is 2.09 au from the Sun and 1.18 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 8400 |
| Provisional designation | 1994 AQ |
| Orbit class | Main-belt Asteroid |
| Rotation period | 3.05 hours |
| Absolute magnitude (H) | 12.99 |
| Orbital period | 4.19 years |
| Semi-major axis | 2.60 au |
| Perihelion – aphelion | 2.09 – 3.11 au |
| Eccentricity | 0.196 |
| Inclination | 13.8° |
| Closest distance between its orbit and Earth's (MOID) | 1.14 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.