(18840) Yoshioba Main-belt Asteroid
Discovered on 8 August 1999 by T. Okuni at Nanyo.
Yoshio Oba (b. 1934) is a retired professor of earth sciences at Yamagata University and an amateur astronomer who observes occultations. He is chairman of the Yamagata Astronomical Society.Naming citation (20020526/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Yoshioba is today
Seen from above the solar system on 2026-10-14: Yoshioba is 2.37 au from the Sun and 2.59 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 18840 |
| Provisional designation | 1999 PT4 |
| Orbit class | Main-belt Asteroid |
| Diameter | 5.32 km (#10,025 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.249 |
| Absolute magnitude (H) | 13.75 |
| Orbital period | 3.69 years |
| Semi-major axis | 2.39 au |
| Perihelion – aphelion | 2.37 – 2.41 au |
| Eccentricity | 0.00970 |
| Inclination | 2.63° |
| Closest distance between its orbit and Earth's (MOID) | 1.38 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Yoshio
All asteroids named after someone called Yoshio