The Twenty-Five-Foot Space Simulator is an 85ft stainless-steel cylinder at the Jet Propulsion Laboratory in Pasadena, California, that is 27ft in diameter.It was declared a National Historic Landmark in 1985 and is on the National Register of Historic Places.It is used for testing spacecrafts in space-like conditions of extreme cold, near-vacuum pressure, and high radiation. Ranger, Surveyor, Mariner, and Voyager spacecraft were all tested in this facility.
