astro.wikisort.org - Asteroid

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]

9524 O'Rourke

Discovery [1]
Discovered by	S. J. Bus
Discovery site	Siding Spring Obs.
Discovery date	2 March 1981
Designations
MPC designation	(9524) O'Rourke
Named after	Laurence O'Rourke (ESAC researcher)[2]
Alternative designations	1981 EJ5 · 1975 NU
Minor planet category	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
Semi-major axis	2.1978 AU
Eccentricity	0.2253
Orbital period (sidereal)	3.26 yr (1,190 days)
Mean anomaly	335.52°
Mean motion	0° 18m 9s / day
Inclination	4.9414°
Longitude of ascending node	286.97°
Argument of perihelion	9.9334°
Physical characteristics
Dimensions	2.920±0.662 km[3]
Geometric albedo	0.273±0.087[3]
Absolute magnitude (H)	14.7[1]

Orbit and classification

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]

Physical characteristics

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]

Naming

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]

References

External links

• Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
• Dictionary of Minor Planet Names, Google books
• Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
• Discovery Circumstances: Numbered Minor Planets (5001)-(10000) – Minor Planet Center
• 9524 O'Rourke at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• 9524 O'Rourke at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

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