(18403) Atsuhirotaisei Main-belt Asteroid
Discovered on 13 January 1993 by Endate, K., Watanabe, K. at Kitami.
Atsuhiro Ikuta (1999-2011) and Taisei Ikuta (2003-2011) were two brothers who loved the stars. They died in an automobile accident on the night of 2011 December 10, on their return home from viewing a total lunar eclipse.Naming citation (20120831/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Atsuhirotaisei is today
Seen from above the solar system on 2026-10-14: Atsuhirotaisei is 2.17 au from the Sun and 1.45 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 18403 |
| Provisional designation | 1993 AG |
| Orbit class | Main-belt Asteroid |
| Diameter | 2.74 km (#15,784 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.314 |
| Absolute magnitude (H) | 14.95 |
| Orbital period | 4.26 years |
| Semi-major axis | 2.63 au |
| Perihelion – aphelion | 1.81 – 3.45 au |
| Eccentricity | 0.312 |
| Inclination | 3.68° |
| Closest distance between its orbit and Earth's (MOID) | 0.824 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.