Hale Telescope

Hale Telescope
Alternative namespalomar
Location(s)Palomar Mountain, California, United States
Coordinates33°21′23″N 116°51′54″W / 33.35628°N 116.86489°W / 33.35628; -116.86489
Altitude1,713 m (5,620 ft)
First lightJanuary 26, 1949, 10:06 pm PST
DiscoveredCaliban, Sycorax, Jupiter LI, Alcor B
Diameter200 in (5.1 m)
Collecting area31,000 sq in (20 m2)
Focal length16.76 m (55 ft 0 in)
Websitewww.astro.caltech.edu/palomar/about/telescopes/hale.html
Location of Hale Telescope
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The Hale Telescope is a 200-inch (5.1 m), f/3.3 reflecting telescope at the Palomar Observatory in San Diego County, California, US, named after astronomer George Ellery Hale. With funding from the Rockefeller Foundation in 1928, he orchestrated the planning, design, and construction of the observatory, but with the project ending up taking 20 years he did not live to see its commissioning. The Hale was groundbreaking for its time, with double the diameter of the second-largest telescope, and pioneered many new technologies in telescope mount design and in the design and fabrication of its large aluminum coated "honeycomb" low thermal expansion Pyrex mirror. It was completed in 1949 and is still in active use.

The Hale Telescope represented the technological limit in building large optical telescopes for over 30 years. It was the largest telescope in the world from its construction in 1949 until the Soviet BTA-6 was built in 1976, and the second largest until the construction of the Keck Observatory Keck 1 in Hawaii in 1993.