Enceladus' Potential Ocean May Be Salty

According to new study results, it would appear that the ocean Saturn's largest moon Enceladus is concealing under a thick layer of ice may be salty. This puts an interesting twist in experts' propositions that the ocean might in fact be inhabitable and inhabited.

Enceladus is now considered to be the most likely candidate for a life-supporting body in the solar system. Scientists consider it the next best thing after Earth, in spite of the fact that its ice crust is miles thick, and that average temperatures there are hundreds of degrees below zero.

All that is theoretically needed for life to have evolved on that moon is a brief period – a few tens of millions of years at most – during which the body is warm. If life managed to grab a foothold there, then it's highly unlikely it was all destroyed.

Measurements conducted using the NASA Cassini orbiter have indicated that a liquid ocean may exist beneath Enceladus' icy crust. The waters within the moon may be kept liquid by the heat of its core.

Other processes may be allowing the water to remain liquid as well, experts say, including the strong interactions that the moon has with its gas giant parent. At its south poles, the moon features cracks in its surface, through which massive plumes of ice are ejected.

These plumes contain ice particles, water vapors and organic molecules, which is what led experts to believe that Enceladus can support life in the first place. But that enthusiasm has somewhat subdued following the release of the new study.

Some of the newest data from Cassini indicate that the geysers the moon ejects from its tiger stripe-like features carry very large concentrations of salt. This is a remarkable finding, since salt is known to lower the point at which water freezes.

But the discovery also has significant implications on how likely the survival of even the most basic lifeforms is on Enceladus. The study was led by scientists at the University of Heidelberg, who were led by expert Frank Postber.

The Cosmic Dust Analyzer instrument on Cassini was used to analyze the vapor plumes during three separate flybys the orbiter did around Enceladus, which is Saturn's sixth-largest moon, Space reports.

“The salt-rich ice grains are, on average, heavier than the salt-poor ice grains. Only a relatively small fraction of the salty particles escape into the E ring,” Postberg says. Some of the particles Enceladus emits are known to contribute to sustaining the Saturnine E ring.