The Hartebeesthoek Radio Astronomy Observatory is a radio astronomy observatory, located in a natural bowl of hills at Hartebeesthoek just south of the Magaliesberg mountain range, Gauteng, South Africa, about 50 km west of Johannesburg. It is a National Research Facility run by South Africa's National Research Foundation. HartRAO was the only major radio astronomy observatory in Africa until the construction of the KAT-7 test bed for the future MeerKAT array.HistoryThe observatory was originally named Deep Space Station 51 and was built in 1961 by the National Aeronautics and Space Administration (NASA). In this role the station assisted in tracking many unmanned United States space missions, including the Ranger, Surveyor and Lunar Orbiter spacecraft (which landed on the Moon or mapped it from orbit), the Mariner missions (which explored the planets Venus and Mars) and the Pioneer missions (which measured the Sun's winds).The first Mars surface images from Mariner 4 were received at DSS 51.
