NASA's Cassini spacecraft has found signs of an ocean at least as big as Lake Superior under a thick layer of ice on one of Saturn's moon.
The results were published in the journal Science and support past signs that the moon has liquid water, providing the possibility that it can host life, according to CNN.
The moon, called Enceladus, is Saturn's sixth-biggest moon. The discovery adds Enceladus to a group of extraterrestrial worlds that feature a subsurface water ocean. The group includes Europa, Jupiter's moon, and Titan, another one of Saturn's moons. Two of Jupiter's other moons, Callisto and Ganymede, could possibly have ice-covered oceans.
"As far as whether one should go first to Europa or Enceladus, I look at this as a kind of a cornucopia of habitable environments in the outer solar system," said Jonathan Lunine, study co-author of Cornell University.
The ocean is located at Enceladus's South Pole, and can surround most, perhaps all of, the moon, which is almost 310 miles across, AOL reported.
Luciano less, lead researcher of Sapienza University of Rome, said the data does not show if the ocean reaches the North Pole. The sea reaches at least 25 miles deep under the ice, which is miles thick. If the ocean was on Earth, it would extend at least from Earth's South Pole up to New Zealand.
Cassini discovered fractures on Enceladus in 2005 called "tiger stripes" in the South Polar area, which discharge jets of water vapor that are rich in salt, CNN reported. The spacecraft also found organic molecules close to the tiger stripes and in regional dust grains.
Researchers believe the ocean is packed between miles of surface ice and a rocky core, AOL reported.
"It's extraordinary what Cassini has been able to do for this small moon," said David Stevenson, researcher from the California Institute of Technology. He added, however, "this is not like mapping the surface of the Earth or mapping the surface of the moon, it's nothing like that. It's much cruder, and it's amazing that we've been able to do as much as we can."
Cassini is already going over its life expectancy, and is set to pass by Enceladus three more times before 2017, when the mission will end.
