Large Binocular Telescope

Large Binocular Telescope

Alternative names	First Light
Part of	Mount Graham International Observatory Steward Observatory
Location(s)	Mount Graham, Graham County, Arizona
Coordinates	32°42′05″N 109°53′21″W / 32.701308°N 109.889064°W / 32.701308; -109.889064
Observatory code	G83
Altitude	3,221 m (10,568 ft)
First light	12 October 2005
Telescope style	optical telescope double telescope
Diameter	8.4 m (27 ft 7 in)
Collecting area	111 m2 (1,190 sq ft)
Focal length	9.6 m (31 ft 6 in)
Mounting	altazimuth mount
Website	www.lbto.org
Location of Large Binocular Telescope
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[edit on Wikidata]

The Large Binocular Telescope (LBT) is an optical telescope for astronomy located on 10,700-foot (3,300 m) Mount Graham, in the Pinaleno Mountains of southeastern Arizona, United States. It is a part of the Mount Graham International Observatory.

When using both 8.4 m (330 inch) wide mirrors, with centres 14.4 m apart, the LBT has the same light-gathering ability as an 11.8 m (464 inch) wide single circular telescope and the resolution of a 22.8 m (897 inch) wide one.^[1]

The LBT mirrors individually are the joint second-largest optical telescope in continental North America, next to the Hobby–Eberly Telescope in West Texas. It has the largest monolithic, or non-segmented, mirror in an optical telescope.

Strehl ratios of 60–90% in the infrared H band and 95% in the infrared M band have been achieved by the LBT.^[2]