W. M. Keck Observatory

W. M. Keck Observatory
The Keck observatory domes atop Mauna Kea
Alternative namesKeck telescope
Location(s)Hawaii
Coordinates19°49′35″N 155°28′28″W / 19.8263°N 155.47441°W / 19.8263; -155.47441
Altitude4,145 m (13,599 ft)
First lightNovember 24, 1990 (1990-11-24), October 23, 1996 (1996-10-23)
Diameter10 m (32 ft 10 in)
Collecting area76 m2 (820 sq ft)
Focal length17.5 m (57 ft 5 in)
Websitekeckobservatory.org
Location of W. M. Keck Observatory
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The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have 10 m (33 ft) aperture primary mirrors, and, when completed in 1993 (Keck I) and 1996 (Keck II), they were the largest optical reflecting telescopes in the world. They have been the third and fourth largest since 2006.