52246 Donaldjohanson
Donaldjohanson photographed by the Lucy spacecraft on 20 April 2025 | |
| Discovery | |
|---|---|
| Discovered by | S. J. Bus |
| Discovery site | Siding Spring Obs. |
| Discovery date | 2 March 1981 |
| Designations | |
| (52246) Donaldjohanson | |
Named after | Donald Johanson (paleoanthropologist) |
| 1981 EQ5 · 1998 YF26 | |
| main-belt · (inner) Erigone | |
| Orbital characteristics | |
| Epoch 25 February 2023 (JD 2460000.5) | |
| Uncertainty parameter 0 | |
| Earliest precovery date | 14 February 1981 |
| Aphelion | 2.830 AU |
| Perihelion | 1.936 AU |
| 2.383 AU | |
| Eccentricity | 0.1876 |
| 3.68 yr (1,343 d) | |
| 186.269° | |
| 0° 16m 4.79s / day | |
| Inclination | 4.424° |
| 262.809° | |
| 213.016° | |
| Physical characteristics | |
| Dimensions | 8 km × 3.5 km |
| 3.895±0.013 km | |
| 251±1 hr | |
| 0.103±0.019 | |
| C | |
| 15.69 | |
52246 Donaldjohanson (provisional designation 1981 EQ5) is a carbonaceous asteroid from the inner regions of the asteroid belt, approximately 8 kilometers (5.0 miles) long and 3.5 kilometers (2.2 miles) at its widest point. It was discovered on 2 March 1981, by American astronomer Schelte Bus at the Siding Spring Observatory in Australia. The C-type asteroid was the 2nd target of the Lucy mission, with the spacecraft flying 960 km (600 mi) from the surface on 20 April 2025, revealing the asteroid to be a contact binary. It was named after American paleoanthropologist Donald Johanson, the discoverer of the "Lucy" hominid fossil.