English: Most space projects live nine lives on the test bench before they are allowed one life in flight.”* The Mariner Mars mission was on a tight schedule in 1964, so testing was not quite as extensive as it was for other missions. A full-size temperature-control model and a proof-test model went through a series of environmental and vibration tests in the 25-foot space simulator at NASA’s Jet Propulsion Laboratory and other test facilities. This photo was taken in June 1964, outside of the Spacecraft Assembly Facility at JPL. In this unusual outdoor setting, the solar panel test took place in a large plastic tent.