article_snippet.sent: Jim Green, director of planetary science at Nasa, noted that a recent study of the Martian atmosphere found 50 per cent of the planet's northern hemisphere once had oceans a mile deep.
article_snippet.sent: Scientists using the Hubble recently provided powerful evidence that Jupiter's moon Ganymede (pictured) has a saltwater, sub-surface ocean, likely sandwiched between two layers of ice .
article_snippet.sent: a recent study of the Martian atmosphere found that water had been present on the planet for up to 1.2 billion year. '
article_snippet.sent: Scientists using the Hubble recently provided powerful evidence that Jupiter's moon Ganymede has a saltwater, sub-surface ocean, likely sandwiched between two layers of ice.
article_snippet.sent: Jupiter's moon Europa and Saturn's satellite Enceladus are also thought to have an ocean of liquid water beneath Jupiter's moon Europa and Saturn's satellite Enceladus surface in contact with mineral-rich rock.
article_snippet.sent: This, according to Nasa, means Jupiter's moon Europa and Saturn's satellite Enceladus may have the three ingredients needed for life as we know it. '
article_snippet.sent: Europa rising above Jupiter's cloud tops. 
highlights_snippet.sent: Signs of water have been found on some of Jupiter and Saturn's moons .