The great blues singer Etta James’ signature song begins, “At laaasst, my love has come along . . . .” This may have been the feeling on May 4th when NASA announced the long-awaited results of Gravity Probe B [1], which are appearing now in Physical Review Letters[2]. Over 47 years and 750 million dollars in the making, Gravity Probe B was an orbiting physics experiment, designed to test two fu...