(21189) Robertonesci Main-belt Asteroid
Discovered on 3 May 1994 by A. Vagnozzi at Stroncone.
Roberto Nesci (b. 1949) is a former Italian professor of astrophysics at La Sapienza University of Rome. He is currently an associate researcher at Istituto Nazionale di Astrofisica/Istituto di Astrofisica e Planetologia Spaziali, and president of the observatory of Foligno (code K56). He develops scientific programs and educational activities in Umbria.Naming citation (WGSBN Bull. 2, #13, 6), IAU / Minor Planet Center, via NASA/JPL
Where Robertonesci is today
Seen from above the solar system on 2026-10-14: Robertonesci is 2.38 au from the Sun and 3.37 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 21189 |
| Provisional designation | 1994 JB |
| Orbit class | Main-belt Asteroid |
| Diameter | 2.70 km (#15,852 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.242 |
| Absolute magnitude (H) | 15.26 |
| Orbital period | 4.06 years |
| Semi-major axis | 2.54 au |
| Perihelion – aphelion | 2.05 – 3.04 au |
| Eccentricity | 0.195 |
| Inclination | 3.15° |
| Closest distance between its orbit and Earth's (MOID) | 1.03 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also named after someone called Roberto
- (4881) Robmackintosh
- (7323) Robersomma
- (7794) Sanvito
- (8742) Bonazzoli
- (9478) Caldeyro
- (10579) Diluca
- (10590) Ragazzoni
- (12470) Pinotti
- (14919) Robertohaver
- (14964) Robertobacci
- (16996) Dahir
- (19224) Orosei
All asteroids named after someone called Roberto