Europa May Not Be a Possible Candidate for Alien Life After All

Friday, 08 May 2015 - 11:11AM
Astrobiology
Europa
Alien Life
Friday, 08 May 2015 - 11:11AM
Europa May Not Be a Possible Candidate for Alien Life After All
Two years ago, observations from NASA's Hubble telescope showed that Europa likely ejected a plume of water vapor, indicating the presence of a subsurface ocean beneath the moon's icy shell. As a result of this phenomenon, scientists declared Europa to be one of the most likely candidates for extraterrestrial life, prompting NASA to plan a landing on Europa specifically to search for alien life. But the scientific community may have jumped the gun, as a new study claims that the Hubble observations were misinterpreted, and Europa is likely dry and lifeless.

"Analysis of far ultraviolet spectra from exposures on Europa leads to the conclusion that earlier reported atmospheric measurements have been misinterpreted," the authors wrote in their paper. "No evidence for the direct injection of H2O into the Europa atmosphere or from Europa into the magnetosphere system, as has been observed at Enceladus in the Saturn system, is obtained in the present investigation."

In 2013, NASA scientists discovered evidence that a plume of water vapor was venting from Europa, which led many researchers to believe that Europa was covered in cracks and fissures that would allow water vapor to vent from the subsurface ocean and create a habitable environment. The authors of the new study point out three problems with the original conclusion: first, the plume is the only direct evidence of water ejection from Europa, the results have yet to be replicated, and nothing unusual was detected on the surface at the time of the proposed ejection.

An analysis of the plasma in Europa's atmosphere led to the conclusion that any ejections may have come from Io. Researchers assumed that the plasma vented from the cracks in Europa's surface, but we now have more information about the composition of the plasma. If it came from Europa, we would expect to find molecular and atomic hydrogen, but instead the researchers found sulfur dioxide ions, which would come from volcanic activity on Io. 

"Our conclusion was that almost everything we were seeing was plasma from Io," said lead author Don Shemansky. "This points to very little output from Europa."

If this is true, then it would seem that there are few cracks or fissures in the surface of Europa, meaning that even if there is a subsurface ocean, there would be no way for it to make contact with the surface. They concluded that the original water plume may have been an anomaly from a crack in in the surface caused by a meteorite crash that subsequently healed, or that it came from Io. Either way, if these results are accurate, the search for alien life would suffer a major setback.

Via Business Insider.
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Space
Astrobiology
Europa
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