File:Plaskett telescope Dominion Astrophysical Observatory Canada 1920.jpg
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Summary
| Description |
English: The 72 inch (1.83 meter) Plaskett telescope at the Dominion Astrophysical Observatory, Victoria, British Columbia, Canada, in 1920. The instrument was the second largest telescope in the world and narrowly missed being the largest; it was completed and saw "first light" on May 6, 1918, only 6 months after the 100 inch Hooker telescope at Mount Wilson Observatory, California. The glass primary mirror is 73 inches in diameter and 12 inches (30 cm) thick, weighs 4340 lbs (1970 kg), and has a 10 1/8 inch hole in the center for the Cassegrain focus. The main tube is 31 feet (9.4 meters) long and weighs 12 tons. It is still in active use. |
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| Source | Retrieved October 28, 2014 from Floyd K. Darrow, "The Giant Canadian Reflector" in Electrical Experimenter magazine, Vol. 7, No. 10, February 1920, p. 1011 on American Radio History website |
| Author | Floyd K. Darrow |
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This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
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| current | 20:19, 30 October 2014 |  | 481 × 692 (65 KB) | Chetvorno | User created page with UploadWizard |
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