Cassini mission scientists have more support for the existence of an underground ocean on Enceladus, in the form of negatively-charged ions present in the moon’s southern ice geysers.

In a report released February 8, 2009, the Cassini Science League announced that researchers have identified these ions using the spacecraft’s plasma spectrometer data from recent flybys of the moon. Negative ions are present on Earth wherever there is liquid water, especially in aerosol form, such as where waves break and near waterfalls. Negative oxygen ions have also been found high in our atmosphere.

Enceladus now joins the short list with Earth, Titan, and comets as places in our solar system where negative ions have been confirmed.

The presence of liquid water beneath Enceladus’ icy crust – and the heat required to keep it liquid – make the little moon a logical place to look for signs of extraterrestrial life having evolved in some form. And while it’s highly improbable that we’d find Enceladian fish swimming in a dark, icy ocean, with the basic ingredients for life present (and enough time) it’s anyone’s guess as to what might exist a microbial level.

“While it’s no surprise that there is water there, these short-lived ions are extra evidence for sub-surface water and where there’s water, carbon and energy, some of the major ingredients for life are present.”

– Andrew Coates, University College London’s Mullard Space Science Laboratory.

Enceladus’ geysers were first discovered by the Cassini spacecraft in 2005.

Read more in Ian O’Neill’s article on Discovery.

Image: NASA/JPL/SSI