Vacuum spheres. These spheres are used in conjunction with a hypersonic wind tunnel (not seen). When the wind tunnel is in use, the vacuum in the sphe

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Vacuum spheres. These spheres are used in conjunction with a hypersonic wind tunnel (not seen). When the wind tunnel is in use, the vacuum in the spheres allows the air to flow through the tunnel at supersonic speeds. Photographed at the National Physical Laboratory, Teddington, UK, in the 1940s.

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Size: 4244px × 3960px
Photo credit: © NATIONAL PHYSICAL LABORATORY © CROWN COPYRIGHT/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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