spacetoday.net: Salt on Europa's icy surface provides new evidence for water ocean below

Posted: Fri, Mar 8, 2013, 6:49 AM ET (1149 GMT)
Europa cutaway salt illustration (NASA/JPL-Caltech)

Planetary scientists reported this week the discovery of a mineral salt on the icy surface of Jupiter's moon Europa that provides them with new evidence that the moon has an ocean of liquid water below its surface. Scientists discovered the presence of magnesium sulfate salt, also known as epsomite, in infrared spectra of the moon taken at the Keck Observatory. The magnesium, they report, could only have come from a salty liquid water ocean below the surface, which would also explain the presence of sodium and potassium atoms detected in a tenuous atmosphere around the moon. The finding indicates that Europa's surface ice and subsurface ocean interact, meaning that energy from the surface may make its way down into the ocean and enhance the prospects for life there.