Is there life on Saturn? Nasa’s Cassini probe could be about to find out…

A spacecraft will this week be sent plunging deep through a fountain of icy spray erupting from an extraterrestrial ocean that could harbour life. The historic fly-by will mark the most exciting attempt yet to unlock the hidden secrets of Saturn’s water-world moon Enceladus. Scientists confirmed last month that the small satellite - which at 310 miles across is a seventh of the size of Earth’s Moon - has a global ocean covered by an icy shell. At 3.22 pm, UK time, on Wednesday, the Cassini probe will shoot through the plume above the moon’s south polar region at an altitude of 30 miles.

This incredible plunge through the Enceladus plume is an amazing opportunity for NASA and its international partners on the Cassini mission to ask, ‘can an icy ocean world host the ingredients for life?

Dr Curt Niebur, Cassini program scientist

The plume is fed by icy geysers which blast 250kg (551lb) of water vapour, ice grains and volatile chemicals into space at 1,360 mph and are thought to have a fiery origin deep beneath the moon’s surface. They have been compared with hydrothermal vents on Earth - volcanic fissures on the ocean floor where sea water percolating through fractures in the bedrock is heated to high temperatures. The complex chemistry around hydrothermal vents gives rise to oases of teeming life in some of the deepest, coldest and darkest corners of the world’s oceans. The plume was first spotted by Cassini in 2005, a year after it arrived in the Saturnian system.