Nearly There
Mirror Lab staff finish placing the first layer of glass on GMT mirror 5’s mold.
Checking for Space
Mirror Lab staff review the glass placed in the mold, checking for space for the last pieces of glass for GMT mirror 5.
Still Checking
A staff member takes a closer look at the glass chunks in mirror 5’s mold, checking for space.
The Final Piece
Mirror Lab staffer Linda Warren places the last piece of glass into the mold.
Nearly 20 Tons of Glass
The GMT mirror 5 mold filled with 38,580 lbs. (17,500 kilograms) of glass, ready for the lid to be placed.
Ready for the Lid: Top View
The glass-filled mirror mold, seen from above.
Lowering the Lid
The lid of the furnace for GMT mirror 5 positioned over the furnace, ready to be lowered in place.
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Ready to Cast
The GMT mirror 5 furnace fully assembled and ready to start.
University of Arizona Casting Crew
The University of Arizona casting crew. From left to right: Ray Perry, Damon Jackson, Linda Warren, Stuart Weinberger, Philip Muir, Randy Lutz, Pat Peak, John Martin, Diana Vargas, Britt Kayner.
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Michael Wall is a Senior Space Writer with Space.com and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.