Delta II - Experiment testing Einstein's theory

VANDENBERG AIR FORCE BASE, Calif.—A Delta II rocket launched from here April 20. The rocket carried the Gravity Probe-B experiment, a project between NASA and Stanford University to test Einstein’s theory of relativity. The experiment will check tiny changes in four gyroscopes on a satellite orbiting 400 miles directly above Earth’s poles. Scientists will use the experiment to measure how space and time are warped by Earth’s presence. (U.S. Air Force photo by Airman 1st Class Craig Cisek)