Dominion Astrophysical Observatory

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For the Dominion Observatory in Ottawa, see Dominion Observatory.

Front of the Plaskett Telescope

Dominion Astrophysical Observatory, located on Little Saanich Mountain, in Saanich, British Columbia, was completed in 1918 by the Canadian Government. Proposed and designed by John S. Plaskett in 1910 with the support of the International Union for Cooperation in Solar Research, when the 72" aperture telescope was constructed, it was very briefly the largest telescope in the world.

The building that houses the telescope was built by McAlpine-Robertson Company of Vancouver for a price of $75,000. Both the building and dome, made by Warner and Swasey Co, are double walled.

The mirror weighs 1,960 pounds and was made by the St. Gobain in their Charleroi glass works in Antwerp, Belgium and shipped only a week before the start of World War I. It was then ground in the United States at the John A. Brashear company in Pittsburgh. The mirror had to be reground twice, once due to a mysterious scratch and the 2nd time due to a flaw in the grinding. This added 2 years to the completion time of the telescope, pushing the date back to 1918. The completed mirror was hauled up Little Saanich Mountain by horse and wagon.

Following completion, Plaskett remained the head of the observatory until 1935.

A spectrograph is fitted to the Cassegrain focus and an imaging CCD is attached to the Newtonian focus.

In 1962, a 48" optical telescope was added to the observatory. The telescope, ordered in 1957, was made by Grubb Parsons of Newcastle-upon-Tyne, England. Its Coude focus is used with a room sized specrograph.

In 1995, the observatory was made the headquarters of the Herzberg Institute of Astrophysics, which operates several Canadian telescopes, both optical and radio, as well as shares in international telescopes, such as the Canada-France-Hawaii Telescope.

The telescopes are in constant use today and are open for visitors year round. An interpretive centre called the Centre of the Universe was recently opened.

As of 2005, the current director was Dr James E Hesser.