Twenty-Five-Foot Space Simulator

The Twenty-Five-Foot Space Simulator is an 85 ft stainless-steel cylinder at the Jet Propulsion Laboratory in Pasadena, California, that is 27 ft 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 spacecraft 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.