The discovery is more likely to relate to water vapour "plumes" that Hubble spotted high above the moon in 2012, but which have not been seen again.
If the plumes are shown to be linked to the moon's sub-surface ocean, it would make the job of investigating the habitable potential of Europa much easier. Instead of having to drill through the moon's thick, icy shell, scientists could analyse the chemical content of the plumes.
Jupiter's moon Europa may have an internal ocean of liquid water, along with the chemistry and energy that life requires. In the cold reaches of the outer solar system, the uppermost portion of Europa’s icy shell forms a rock-hard skin which fractures and deforms to create cracks, ridges, and bands.
The 1,900-mile-wide moon is thought to hold two to three times as much water as all the Earth's oceans.
Europa's ocean is believed to be salty, and warmed by powerful tidal forces generated by Jupiter's gravity so that it remains unfrozen.
Along with the chemistry and energy that life requires. In the cold reaches of the outer solar system, the uppermost portion of Europa’s icy shell forms a rock-hard skin which fractures and deforms to create cracks, ridges, and bands.