South African Astronomical Observatory (SAAO) 0.5 metre telescope dome, with a full Moon to its left. The building is enclosed by silvered blinds, which reduce the amount of heat taken in during the day. If the air inside the building is too warm, it can take a long time to equalise with the cool air outside. Mixing air of different temperatures causes local turbulence, which impairs the viewing conditions. This observatory is based at Sutherland, South Africa. This site has an altitude of 1800 metres, which places it above much of the cloud and far away from light pollution. The observatory was opened in the early 1970s.