On Wednesday, NASA confirmed that Saturn’s sixth largest moon Enceladus may host a global ocean beneath its icy surface. The assumption is based on data gathered by NASA/ESA’s Cassini mission and a new interpretation of that data.
NASA scientist said that if the global ocean theory is correct, Enceladus is our solar system’s most habitable candidate after Earth. Chris McKay form the California-based NASA’s Ames Research Center noted that the moon holds liquid water, nitrogen and organic carbon which are elements essential to life along with a source of heat.
All these elements were detected around Enceladus’ south pole during several close flybys performed by Cassini orbiter. Nevertheless, the 18-year-old spacecraft does not have the necessary instruments to detect more complex molecules, so it resumed to simple particles found in the gases and water vapors ejected into space by the geologically active moon.
Larry Esposito of the University of Colorado said that the 300-mile-wide moon’s vast ocean is a welcoming environment to basic life forms that could use hydrogen to generate methane from carbon dioxide just like several types of bacteria known as methanogens do on Earth because their environments lack oxygen.
Ronald Oremland of the US Geological Survey thinks that Enceladus microorganisms could better feast on acetylene, a compound believed to be present in the moon’s ocean and serve as fast-food for microorganisms.
But NASA team is now more interested in the active geysers in the moon’s southern polar region and the recent data that suggest Enceladus my hide a global ocean underneath its surface rather than a regional one as previously thought.
Following a 7-year-long research, NASA scientists reached a consensus that the violent jets of gas and vapors are produced by a liquid layer of water between the moon’s core and icy surface.
In a recently published research paper, NASA scientists wrote that they were able to detect a hidden global ocean on Enceladus from the data gathered by Cassini over the course of more than a decade.
“This was a hard problem that required years of observations, and calculations involving a diverse collection of disciplines, but we are confident we finally got it right,”
Peter Thomas, one of the authors of the study, wrote on NASA’s blogsite.
Thomas explained that his colleagues detected a wobble in the moon’s orbit that could be triggered only by a vast ocean hidden under its surface. Researchers explained that if the moon was rock solid from its core throughout its crust the wobble would be a lot smaller. As a follow-up, the Cassini mission team plans to learn why the subsurface remained in liquid state despite frigid temperatures.
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