| Discovery [1] | |
|---|---|
| Discovered by | S. J. Bus |
| Discovery site | Siding Spring Obs. |
| Discovery date | 2 March 1981 |
| Designations | |
| (9524) O'Rourke | |
Named after | Laurence O'Rourke (ESAC researcher) [2] |
| 1981 EJ5 ·1975 NU | |
| main-belt ·(inner) | |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 41.90 yr (15,305 days) |
| Aphelion | 2.6928 AU |
| Perihelion | 1.7027 AU |
| 2.1978 AU | |
| Eccentricity | 0.2253 |
| 3.26 yr (1,190 days) | |
| 335.52° | |
| 0° 18m 9s / day | |
| Inclination | 4.9414° |
| 286.97° | |
| 9.9334° | |
| Physical characteristics | |
| Dimensions | 2.920±0.662 km [3] |
| 0.273±0.087 [3] | |
| 14.7 [1] | |
9524 O'Rourke, provisionally designated 1981 EJ5, is an asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered on 2 March 1981, by American astronomer Schelte Bus at the Siding Spring Observatory in New South Wales, Australia. The asteroid was named after Laurence O'Rourke, a researcher at the European Space Astronomy Centre. [2]
O'Rourke orbits the Sun in the inner main-belt at a distance of 1.7–2.7 AU once every 3 years and 3 months (1,190 days). Its orbit has an eccentricity of 0.23 and an inclination of 5° with respect to the ecliptic. [1] It was first observed as 1975 NU at Crimea–Nauchnij in 1975, extending the asteroid's observation arc by 6 years prior to its official discovery observation. [2]
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 2.920 kilometers in diameter and its surface has an albedo of 0.273. [3]
As of 2017, O'Rourke's spectral type, as well as its rotation period and shape remain unknown. [1] [4]
This minor planet was named after Laurence O'Rourke (born 1970), a researcher at the European Space Astronomy Centre in Madrid, Spain, and a coordinator of ESA's Rosetta mission. [2] [5] The approved naming citation was published by the Minor Planet Center on 12 July 2014 ( M.P.C. 89078). [6]
