(18728) Grammier Main-belt Asteroid
Discovered on 22 May 1998 by LONEOS at Anderson Mesa.
Richard (“Rick”) S. Grammier (1955-2011) was director of solar system exploration at NASA's Jet Propulsion Laboratory. He worked as manager or project manager on missions such as Cassini, Stardust, Deep Impact and Juno.Naming citation (20120506/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Grammier is today
Seen from above the solar system on 2026-10-14: Grammier is 3.00 au from the Sun and 2.22 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 18728 |
| Provisional designation | 1998 KZ3 |
| Orbit class | Main-belt Asteroid |
| Diameter | 4.79 km (#11,027 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.212 |
| Rotation period | 13.1 hours |
| Absolute magnitude (H) | 13.97 |
| Orbital period | 4.42 years |
| Semi-major axis | 2.70 au |
| Perihelion – aphelion | 2.17 – 3.22 au |
| Eccentricity | 0.194 |
| Inclination | 5.42° |
| Closest distance between its orbit and Earth's (MOID) | 1.19 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also discovered on 22 May 1998
- (9466) Shishir
- (11187) Richoliver
- (11730) Yanhua
- (11735) Isabellecohen
- (12104) Chesley
- (12106) Menghuan
- (12107) Reneebarcia
- (12108) Jamesaustin
- (12529) Reighard
- (12530) Richardson
- (12860) Turney
- (12861) Wacker