Science: NASA, ESA, and W. Sparks (STScI); Image: NASA, ESA, W. Sparks (STScI), and the USGS Astrogeology Science Center
These composite images show a suspected plume of material erupting two years apart from the same location on Jupiter's icy moon Europa. The images bolster evidence that the plumes are a real phenomenon, flaring up intermittently in the
same region on the satellite. Both plumes, photographed in ultraviolet light by NASA's Hubble's Space
Telescope Imaging Spectrograph, were seen in silhouette as the moon passed in
front of Jupiter.
The newly imaged plume, shown at right, rises about 62 miles above Europa's
frozen surface. The image was taken Feb. 22, 2016. The plume in the image at left, observed by Hubble on March 17, 2014, originates from the same location. It
is estimated to be about 30 miles high. The snapshot of Europa, superimposed
on the Hubble image, was assembled from data from NASA's Galileo mission to
The plumes correspond to the location of an unusually warm spot on the moon's icy crust, seen in the late 1990s by the Galileo spacecraft. Researchers
speculate that this might be circumstantial evidence for water venting from the moon's subsurface. The material could be associated with the global ocean that is believed to be present beneath the frozen crust.