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]

• 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 viewer · Orbit parameters · Physical parameters