The Algonquin Radio Observatory is a radio observatory located in Algonquin Provincial Park in Ontario, Canada. It opened in 1959 in order to host a number of the National Research Council of Canada's ongoing experiments in a more radio-quiet location than Ottawa.In 1962 it was selected as the site for the Algonquin 46m radio telescope, which has been the site's primary instrument through most of its history. An earlier 10 m instrument was set up in 1961 though was not equipped with a drive mechanism until 1964. The site also hosts a hydrogen maser, a standard feature for radio telescopes that can also serve to receive telemetry from deep space missions. Other instruments formerly at the site included a solar-observing array of thirty-two 10 ft dishes, and a single 1.8 m solar flux monitor observing at 10.7 cm wavelength, and a 18 m radio telescope from the University of Toronto.In the late 1980s, as a part of an ongoing shift of operations from the NRC, operations of the ARO were passed to the Center for Research in Earth and Space Technology . The multi-dish solar observatory was sold in the early 2000s, and the second solar observatory antenna was moved to the Dominion Radio Astrophysical Observatory in British Columbia. The Observatory's main uses today are in very long baseline interferometry experiments mostly in geodesy, a primary global positioning system site, some use for satellite downlink, and other general experiments. Since 2007, the site has been operated by Thoth Technology Inc.
