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Largest single optical telescope

Largest single optical telescope
Who
Gran Telescopio Canarias (GTC)
Where
Spain (La Palma,Canary Islands)
When
13 July 2007

The Gran Telescopio Canarias (GTC) achieved 'first light' on 13 July 2007. Located on the island of La Palma, Canary Islands, Spain, the GTC has a main mirror made up of 36 hexagonal segments giving it a total diameter of 10.4 m (34 ft). The huge telescope and its 35-m (114-ft) dome cost 130 million euros to construct over seven years.