NASA's Gravity Probe B (GP-B) Relativity Mission science payload has been mated to the spacecraft bus by Lockheed Martin in Sunnyvale, California. Due for launch late this year, the GP-B is expected to provide precise tests of two predictions of Albert Einstein's theory of general relativity. Operating in polar orbit and using its cryogenically cooled gyros, GP-B will measure how space and time are warped by the presence of the Earth and how the Earth's rotation drags space-time around with it.
Source: Flight International
