Malcolm Hartley is an English-born astronomer, discoverer of minor planets and comets, who works at the Siding Spring Observatory in Australia.
He's best known for his discovery and co-discovery of 10 comets since the 1980s, among them 79P/du Toit-Hartley, 80P/Peters–Hartley, 100P/Hartley, 110P/Hartley, and C/1984 W2. Unfortunately for Hartley, in 2002, "the Anglo-Australian Observatory retrofitted its Schmidt to perform multi-object spectroscopy, essentially halting all astrophotography with the telescope and ending any future possibility for comet discovery". In November 2010, he visited NASA's Jet Propulsion Laboratory facility in California to witness the EPOXI mission flyby of comet 103P/Hartley on 4 November 2010.
Hartley is credited by the Minor Planet Center with the discovery of 3 asteroids made at the Siding Spring Observatory between 1996 and 1998, with (21374) 1997 WS22 and (65674) 1988 SM being near-Earth objects of the Amor group of asteroids.
The outer main-belt asteroid 4768 Hartley was named in his honour, being deputy astronomer of the U.K. Schmidt telescope at Siding Spring, with which this minor planet was discovered. Naming citation was published on 27 June 1991 (M.P.C. 18464).