Pictured here are Jupiter's northern lights (aurora borealis) which measure twice the size of Earth. Taken by the Hubble Space Telescope, the ultraviolet data is in blue. The magenta flash is a powerful x-ray source taken by the Chandra X-ray observatory. See the animation of a rotating Jupiter on the left. It emits radiation every 45 minutes and was first detected in 1979 by the Einstein x-ray satellite, although the location of the source was unknown. Scientists still don't have an explanation for the emission. It is one of the mysteries of the jovian planet that may take a while to solve.