Though it's five times farther from the Sun than Earth, and therefore so cold that ice becomes as hard as rock, Jupiter's moon Europa may be the first place to go to look for extraterrestrial life. Ever since the moon, which superficially resembles a cracked eggshell, was photographed close-up by the Voyager space probe, scientists have been intrigued by its potential as a niche for life.
For over the past 30 years it has been hypothesized that the icy crust covers a subsurface ocean. Where there is water there could be life. Now NASA's Hubble Space Telescope has found something the Jovian probes... Read more