First eight-meter Gemini mirror blank is fused

Corning Incorporated (Canton, NY) recently made the first of two mirror blanks for the Gemini Telescopes Project, which will use two 8-m mirrors in tandem. The 8.1-m-diameter mirror blank was made by fusing 55 hexagonal pieces of ultralow-expansion (ULE) glass in a 1700°C furnace.

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