Onsala Space Observatory

The Onsala Space Observatory ( Onsala Swedish rymdobservatorium, known internationally as the Onsala Space Observatory OSO ) is the Swedish government institution for Radio Astronomy, 45 km south of Gothenburg in Onsala. The observatory is part of the Institute of Space and Earth Sciences Chalmers University of Technology.

The Observatory operates two radio telescopes, one with 20 m diameter reflector (built 1975-1976 ), in the centimeter and millimeter range up to a minimum of three millimeters wavelength working and a 25-meter reflector diameter ( built in 1963 ). This works in the centimeter range and is also used for Very Long Baseline Interferometry. The observatory formerly operated a millimeter Telescope ( SEST ) at La Silla Observatory and is at the Atacama Pathfinder Experiment (APEX) involved.