Francis Everitt gave an interesting talk yesterday at the departmental colloquium about the experimental mission - Gravity Probe B, which completed earlier this year, over forty years after its original conception. The aim of the mission was to verify Einstein's Theory of General Relativity, by investigating two extraordinary phenomena predicted by Einstein: the geodesic effect (warping of spacetime due to the Earth) and the frame dragging effect (the extent to which the earth drags its spacetime round with it). The project is a fantastic story of human vision, tenacity and imagination.