Onsala Space Observatory

Founded in 1949, hosted by Chalmers University of Technology and operated on behalf of the Swedish research council, Onsala Space Observatory is the Swedish national facility for radio astronomy. The observatory provides scientists with equipment to study the Earth and the rest of the Universe. Several radio telescopes are operated in Onsala and these take part in international projects. The observatory is also a geodetic fundamental station.

Examples of facilities and activities are:

• The 20 m and 25 m telescopes used for studies of the birth and death of stars
• The LOFAR station which is one part of an international network of antennas for studies of, e.g., the early history of the Universe
• The VLBI telescopes which are linked to telescopes in different countries for better resolution ("sharper images") and for measurements of the Earth
• Space geodesy activities including VLBI, GPS/GNSS, gravimeters and tide gauges to measure e.g. Earth's rotation, movements in Earth's crust, sea level height, and water vapor in the atmosphere
• Time keeping by two hydrogen maser clocks and one cesium clock contribute to establishing the official Swedish time and international time.

The presentation will provide a review of the history of the observatory as well as an introduction to the facilities and some of the current activities and results. The presentation will be given by Dr. Jan Johansson who has worked with space geodesy and geodynamics at Onsala Space Observatory for more than 30 years.