Inside a moon of Saturn, beneath its icy veneer and above its rocky core, is a sea of water the size of Lake Superior, scientists announced on Thursday.
The findings, published in the journal science, confirm what planetary scientists have suspected about the moon, Enceladus, ever since they were astonished in 2005 by photographs showing geysers of ice crystals shooting out of its south pole. For many researchers, this tiny, shiny cue ball of a moon, just over 300 miles wide, is now the most promising place to look for life elsewhere in the solar system, even more than Mars. Enceladus (pronounced en-SELL-a-dus) is caught in a gravitational tug of war between Saturn and another moon, Dione, which bends its icy outer layer, creating friction and heat. In the years since discovering the geysers, NASA’s Cassini spacecraft has made repeated flybys of Enceladus, photographing the fissures (nicknamed tiger stripes) where the geysers originate, measuring temperatures and identifying carbon-based organic molecules that could serve as building blocks for life. The discussion on the possibility of extraterrestrial life in the solar system centers on four bodies: Mars; Enceladus; Europa, a moon of Jupiter; and Titan, another moon of Saturn. Dr. McKay, who was not involved with gravity measurements, noted that only Enceladus was known to possess the four essential ingredients for life, at least as it exists on Earth: liquid water, energy, carbon and nitrogen. Still, life on Enceladus is perhaps a long shot. The sea is at freezing temperature and in continual darkness. And the water may have been liquid only in the recent past, a few tens of millions of years, a blink in the 4.5-billion-year history of the solar system. But scientists also do not know how long it takes life to get started, and some think it could happen quickly.
http://mobile.nytimes.com/2014/04/04/science/space/a-moon-of-saturn-has-a-sea-scientists-say.html?from=science
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