Space, Einstein & Technology: The NASA-Stanford Gravity Probe B mission

C.W. Francis Everitt, W.W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA

Gravity Probe B (GP-B) was launched from Vandenberg Air Force Base on 20 April and entered its science phase 27 August 2004. It will perform two highly accurate tests of two effects in General Relativity, Einstein's theory of gravitation, by means of orbiting gyroscopes: 1) the 6.6 arc-s/year geodetic effect due to the motion of the gyroscope through the curved space-time around the Earth; 2) the 0.042 arc-s/year frame-dragging effect due to the 'dragging around' of space and time by the rotating Earth. In addition to describing GP-B science and the many new technologies developed for the experiment, a few comments will be offered on the management challenges of developing a space mission and the real-life experience of running a physics experiment on-orbit.