http://space.newscientist.com/article/dn13938-gravity-probe-b-scores-f-in-nasa-review.html The noisy data meant that GPB could not measure the effects as precisely as astronomers had by firing laser beams at mirrors left on the Moon by the Apollo astronauts. GPB managers had asked for additional funding to March 2010 to try to extract more information from the data, but the review panel doubted they could reach their goals. It warned that the reduction in noise needed to test rigorously for a deviation from general relativity "is so large that any effort ultimately detected by this experiment will have to overcome considerable (and in our opinion, well justified) scepticism in the scientific community". Gravity Probe B's principal investigator, Stanford University physicist Francis Everitt, could not be reached for comment. The panel gave top ranking to SWIFT, which launched in 2004 to study fleeting cosmic explosions called gamma-ray bursts.