Hubble sees possible water plumes on Europa

Nature : Europa, one of Jupiter’s moons, is believed to have liquid oceans underneath its icy surface. A new image from the Hubble Space Telescope has revealed possible plumes of water spraying from the moon’s southern pole; the plumes are similar to those seen on Saturn’s moon Enceladus . Lorenz Roth of the Southwest Research Institute in San Antonio, Texas, and his colleagues had been unsuccessful when they previously looked for plumes in images of Europa taken by Hubble‘s Advanced Camera for Surveys. But a 2.7-hour exposure taken in December 2012 using Hubble‘s UV camera revealed two blobs of hydrogen and oxygen near the moon’s southern pole. Roth’s team says the blobs are most likely the result of water vapor plumes 200 km high. At the time the image was taken, Europa was at its farthest point from Jupiter. Because of that, the researchers believe that tidal stresses may explain why no previous observations revealed plumes.