An Australian radio astronomy observatory located 20 kilometres 12 miles north of Parkes, New South Wales. The instrument is an altazimuth mounted, prime-focus, 64-metre 210-foot single dish. It was commissioned in 1961 and operated by the Commonwealth Scientific and Industrial Research Organization CSIRO Division of Radiophysics as the Australian National Radio Astronomy Observatory. In 1988 it became a unit of the Australia Telescope. It can serve as a stand-alone telescope or as a member of a long-baseline array. The Parkes dish was the first to be built in the southern hemisphere. It was used for the identification of the first quasar in 1963, and to discover many interstellar molecules and over half the known pulsars. It has also been used as an additional element in the Deep Space Network for tracking spacecraft, for example during the Voyager 2 encounters with Uranus and Neptune and the Giotto mission to Halley’s Comet.