Number 236 (Story #2), August 7, 1995 by Phillip F. Schewe and Ben Stein GENERAL RELATIVITY HAS SURVIVED ANOTHER TEST. Einstein's theory predicts that the light from a distant star will be slightly deflected in the gravitational field of a large body. In 1919 Arthur Eddington observed just such a deflection of starlight as it grazed the sun. The measurement, in agreement with the relativity prediction, helped to make Einstein world famous. Performing a new version of this test, astronomers from Harvard, MIT, and the Haystack Observatory (contact Brian Corey, 508-692-4764) have used antennas in Massachusetts and California to measure the deflection of radio waves coming from the extragalactic object 3C279 as they passed near the sun. The use of coordinated but widely spaced antennas (very long baseline interferometry) produces a much more accurate measurement than is possible with a single radio telescope. The ratio of measured to predicted deflection was 0.9998, with an uncertainty of 0.0008. (D.E. Lebach et al., 21 Aug., 75, 1439 Physical Review Letters.)