Jupiter's largest moons don't go completely dark when the giant planet blocks their sunlight, astronomers have found.
The discovery could reveal more about Jupiter's mysterious upper atmosphere, which the researchers suspect is responsible for keeping the moons lit when they are not directly illuminated by the sun. This research could also help scientists better understand the atmospheres of alien planets, study team members said.
The NASA/ESA Hubble Space Telescope has discovered water vapour erupting from the frigid surface of Jupiter's moon Europa, in one or more localised plumes near its south pole.
Europa is already thought to harbour a liquid ocean beneath its icy crust, making the moon one of the main targets in the search for habitable worlds away from Earth. This new finding is the first observational evidence of water vapour being ejected off the moon's surface.