Giant Telescope Mirror for Future Observatory to Be Cast Saturday

[Judi Lynn]

Giant Telescope Mirror for Future Observatory to Be Cast Saturday
By Mike Wall, Senior Writer | August 23, 2013 01:00pm ET

An enormous mirror will be cast inside a scorching-hot furnace Saturday (Aug. 24), marking a key milestone in the development of a future telescope that will collect more light than any instrument built to date.

The Giant Magellan Telescope mirror, the third of the seven primary mirrors planned for the observatory, will be 27 feet (8.4 meters) across and weigh 20 tons when complete. It will be forged from chunks of borosilicate glass subjected to temperatures of 2,140 degrees Fahrenheit (1,170 degrees Celsius) inside a rotating furnace Saturday at the University of Arizona's Steward Observatory Mirror Lab in Tucson.

Once cast and polished, these seven mirrors will be arranged to function as a single mirror 80 feet (24.5 m) in diameter, giving the $700 million GMT a resolving power 10 times greater than that of NASA's famous Hubble Space Telescope once the new instrument is up and running in northern Chile in 2020. (See more images of the Giant Magellan Telescope (Gallery))

http://www.space.com/22494-giant-magellan-telescope-mirror-casting.html

[jakeXT]

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