File:Plaskett telescope Dominion Astrophysical Observatory Canada 1920.jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Original file (481 × 692 pixels, file size: 65 KB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents

Summary

[edit]
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.
Date
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

Licensing

[edit]
Public domain
Public domain
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.
United States
United States
This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current20:19, 30 October 2014Thumbnail for version as of 20:19, 30 October 2014481 × 692 (65 KB)Chetvorno (talk | contribs)User created page with UploadWizard

You cannot overwrite this file.

There are no pages that use this file.

File usage on other wikis

The following other wikis use this file:

Retrieved from "https://commons.wikimedia.org/w/index.php?title=File:Plaskett_telescope_Dominion_Astrophysical_Observatory_Canada_1920.jpg&oldid=424397068"