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Photo Friday: Opening fusion’s 48-ton door (1979)

This 1979 photo is of a woman at the U.S. Department of Energy’s Lawrence Livermore National Laboratory (LLNL) opening a 97,000 pound (48.5 ton) door.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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This 1979 photo is of a woman at the U.S. Department of Energy's Lawrence Livermore National Laboratory (LLNL) opening a 97,000 pound (48.5 ton) door. Eight feet thick and nearly twelve feet wide, this concrete-filled door included a special bearing in the hinge that allowed a single person to open or close it. The door was used to shield the Rotating Target Neutron Source-II (RTNS-II), which scientists used to study the properties of metals and other materials that could be used inside theoretical fusion power plants.

Photo credit: U.S. Department of Energy, Lawrence Livermore National Laboratory.