(20139) Marianeschi Main-belt Asteroid
Discovered on 19 August 1996 by A. Vagnozzi at Stroncone.
Edmondo Marianeschi (1922-2010) was one of the most important Italian metallurgists. He wrote important books and obtained several international patents on steel manufacturing. An amateur astronomer, he designed, among others, the Montecitorio square sundial in Rome.Naming citation (MPC batch dated 2018-04-30), IAU / Minor Planet Center, via NASA/JPL
Where Marianeschi is today
Seen from above the solar system on 2026-10-14: Marianeschi is 2.82 au from the Sun and 3.77 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 20139 |
| Provisional designation | 1996 QU |
| Orbit class | Main-belt Asteroid |
| Diameter | 2.94 km (#15,353 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.213 |
| Absolute magnitude (H) | 14.58 |
| Orbital period | 3.52 years |
| Semi-major axis | 2.32 au |
| Perihelion – aphelion | 1.72 – 2.92 au |
| Eccentricity | 0.259 |
| Inclination | 22.5° |
| Closest distance between its orbit and Earth's (MOID) | 0.869 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.