Saturn moon ‘may contain liquid water’

SCIENTISTS say supersonic plumes of gas and dust shooting off one of Saturn’s moons suggest it has liquid water, a key building block of life.

Their research, appearing in tomorrow’s issue of the journal Nature, adds to the growing push to explore further the moon Enceladus, as one of the solar system’s most compelling places for potential life.

Using images from Nasa’s Cassini probe, astronomers had already discovered that the mysterious plumes shooting from Enceladus’ icy terrain contain water vapour. New calculations suggesting the gas and dust spew at supersonic speeds make the case for liquid, said study lead author Candice Hansen of Nasa’s Jet Propulsion Lab in California. Her team calculated the plumes travel at more than 1,360 mph (2,188kph).

Reaching that speed “is hard to do without liquids”, she said. While her paper offers more evidence building on what others have found, she added that her research is not the final proof of liquid water on Enceladus.

Other planetary scientists, such as Andrew Ingersoll at the California Institute of Technology, said the research is good, but that it is possible to achieve such speeds with ice particles and at cooler temperatures.

Carolyn Porco, the head of the Cassini camera team and an astronomer who didn’t take part in the research, said “the evidence in my mind is building on liquid water”. That moon, one of 60 circling Saturn, “has become the go-to place” for exploration in the outer planets, she said.