(10501) Ardmacha Main-belt Asteroid
Discovered on 19 July 1987 by E. F. Helin at Palomar.
The city of Armagh is steeped in history. It is the ecclesiastical capital of Ireland and home of the venerable Armagh Observatory. Tradition relates that St. Patrick chose what used to be called Ard Macha as the center of his mission in Ireland, building his main church on one of the seven hills of Armagh in 445.Naming citation (20010109/MPCPages.arc), IAU / Minor Planet Center, via NASA/JPL
Where Ardmacha is today
Seen from above the solar system on 2026-10-14: Ardmacha is 2.77 au from the Sun and 3.74 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 10501 |
| Provisional designation | 1987 OT |
| Orbit class | Main-belt Asteroid |
| Diameter | 5.88 km (#9,116 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.204 |
| Absolute magnitude (H) | 13.82 |
| Orbital period | 4.48 years |
| Semi-major axis | 2.72 au |
| Perihelion – aphelion | 1.99 – 3.44 au |
| Eccentricity | 0.266 |
| Inclination | 8.70° |
| Closest distance between its orbit and Earth's (MOID) | 0.994 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.