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Algonquin Radio Observatory

"Welcome to Algonquin Radio Observatory! Join us on our journey as we explore the universe using the electromagnetic spectrum."

    a message from the director, Dr. Brendan Quine.

The Algonquin Radio Observatory (ARO) is Canada’s national radio observatory featuring Canada's premiere Earth station facility. ARO is a division of space technology company Thoth Technology Inc.

Completed and commissioned in the 1965, ARO’s 46m antenna is the largest antenna in Canada and one of the largest in North America. The observatory is situated on a 100 acre wild and breathtakingly beautiful site in the North of Algonquin park on Lake Travers, deep inside the park. The observatory hosts a suite of state-of-the-art scientific equipment including its own atomic clock and still operates with a state-of-the-art technical capability.

ARO is the official ground station for Northern Light, Canada's mission to Mars.

The observatory was founded by Arthur Covington who directed the Observatory until 1978. Covington was also responsible for the expansion of the site and the construction of the 46m antenna. Operating at radio frequency, the giant parabolic dish focuses electromagnetic radiation towards the focus cabin mounted on four legs above the surface. The efficiency gained by the large reflecting surface enables the telescope to receive signals from Mars and to determine precisely the location of the telescope with respect to Pulsars in neighboring star systems. The construction and operation of the observatory was reported in Solar Physics by Arthur Covington in 1969. 

Historical Highlights

ARO was  the first telescope system to demonstrate Very Long Baseline Interferometry (VLBI) a technique that surpasses the accuracy of GPS and now enables the measurement of phenomena such as continental drift. The team comprised the National Research Council of Canada, Dominion Radio Astronomical Observatory, Penticton, the University of Toronto and Queen's University. The technique was reported by N. W. Broten in the Journal Science in 1967. The team was awarded the Rumford Medal for their achievement. Observations reported in Nature by Andrew and Purton provided an upper limit for the radio emission of supernova Delphini 1967.  The telescope was used to observe emission lines from large molecules including HC5N, HC7N, HC9N and HC11N. This work is credited with the discovery of cyanodiacetylene in the interstaller medium. The observatory was also utilised to study the emissions of H2O, HN3 and OH in the gaseous nebulae in the milky way and other galaxies. Other work included the study of planetary nebulae, the black hole source Cyg X-1, pulsar 0329+54, the Sun, variable extra-galactic sources including B1 Lac, and the development of a database of 2.8 cm flux measurements for a wide range of objects.

Wikipedia provides further historical accounts of the Observatory's activities. The antenna is currently used for pulsar research,  space tracking and Deep Space Network communications. The antenna recently hosted York University's space engineering field school for students in their final year of a BaSc in Space Engineering. Students developed and executed tracking software to point the antenna and also helped in the revitalization project. 

The Observatory is operated by Thoth Technology, a company that provides specialist space-tracking and communications services with near-Earth and interplanetary spacecraft, using the 46m antenna. For information regarding the observatory's technical services including deep space network, antenna time and other research activities at the observatory please visit Thoth's website or contact Thoth directly. Thoth now also offers site access and comfortable accommodation for educators, research users and visitors. 


Our Observatory House offers comfortable accommodation surrounded by the natural beauty of Algonquin Park and a chance to see Canada's largest radio telescope. Take a tour of the radio observatory for a behind the scenes view of one of Canada's engineering marvels. Packages include full meal plan, accommodation and use of the observatory's facilities.


Catch ARO coverage on Discovery Channel's Daily Planet