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When built, the GMT will be the largest optical telescope in existence. At the heart of the giant observatory are seven off-axis mirrors, each spanning 28 feet, produced in the UA's Richard F. Caris Mirror Lab.
When built, the GMT will be the largest optical telescope in existence. At the heart of the giant observatory are seven off-axis mirrors, each spanning 28 feet, produced in the UA's Richard F. Caris Mirror Lab. (Artists' concept: GMTO)