Anisotropy in blackbody radiation shows Earth's motion

Soon after the 3‐K cosmic blackbody radiation was discovered, many wondered how isotropic the all‐pervading radiation in fact was. Now a Princeton group reports that the radiation is isotropic to within 1 part in 1000 and a Berkeley group reports isotropy to 1 part in 3000. Furthermore, they both observe the motion of the Earth with respect to the radiation, so that one can tell how fast the Earth (or the Milky Way) is moving with respect to distant matter in the universe.