Onsala Space Observatory (OSO) is a Swedish national facility for radio astronomy, operated by Chalmers University of Technology. The observatory is located in Onsala, just south of Gothenburg. OSO hosts a range of instrumentation for both single-dish and interferometric observations at centimetre and millimetre wavelengths. It is also home to the Swedish LOFAR station, Onsala85.
The first radio telescope at Onsala was built in 1946, making it one of the oldestsites in the world dedicated to radio astronomy. Since then, a number of different telescopes have been constructed at the observatory, most notably the 25-metre telescope which was inaugurated in 1964. This dish is still in regular use today for single-dish observations with a variety of receivers. In addition to its astronomical work, OSO has also been involved in several satellite tracking projects over the years.
The focus of research at OSO is currently on star formation and evolution, cosmology, astrochemistry and planetary science. Recent highlights include the detection of water vapour on Jupiter’s moon Europa using the Atacama Large Millimeter/submillimeter Array (ALMA), and the discoveryof an extrasolar planet through pulsar timing measurements made with the Nançay Radio Telescope.
Looking to the future, OSO will continue to play a key role in cutting-edge astronomical research as we explore our Universe like never before.