Chamber A in Building 32 at the Johnson Space Center is a steel vacuum vessel 90 feet tall and 55 feet across, built so a whole Apollo spacecraft, with its crew aboard, could be put through the conditions of space without leaving Houston. Construction started in late 1963, and after a structural failure in 1964 the chamber passed acceptance in April 1965. Its pumps could simulate the vacuum 130 miles up, its walls could be chilled to minus 230 degrees Fahrenheit, and banks of carbon-arc lamps stood in for the sun. People lived in it. In 1966 three test subjects spent eight days sealed inside an Apollo command module in the chamber, and a second test that autumn carried astronauts Joseph Kerwin and Edward Givens with engineer Joseph Gagliano. In June 1968 Kerwin, Vance Brand and Joe Engle finished an eight-day run that certified the redesigned Block II spacecraft for Apollo 7, the first crewed Apollo flight.
Half a century later the chamber took on its largest job. Upgraded with a helium-cooled shroud reaching 11 degrees above absolute zero, it held the optics and science instruments of the James Webb Space Telescope, tested together for the first time, from 10 July to 18 November 2017. Hurricane Harvey made landfall on 25 August, partway through, and dropped more than 50 inches of rain on parts of the Houston area. Engineers worked overnight shifts through the storm and the test kept going.
The Space Environment Simulation Laboratory was listed as a National Historic Landmark in 1985.
Getting there
29.5607, -95.0882
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