Findings from NASA’s Cassini spacecraft suggest that one of Saturn’s moons, Enceladus, could potentially support organic life. The complex organic molecules detected by the craft represent the clearest evidence yet for life beyond Earth. The findings were published in the journal Nature, and were reported by Reuters yesterday. Cassini passed Saturn’s moon in 2005, and researchers are still analyzing its data, and likely will be for years. The analysis was conducted by a team led by Frank Postberg and Nozair Khawaja from Germany’s University of Heidelberg.
The researchers discovered fragments of complex organic molecules that had emerged from geysers on the moon’s ice-covered surface. They contained chains and rings consisting of hundreds of atoms.
The data was gathered during flybys between 2004 and 2008. At that point, there was very little contamination from dust coming from elsewhere in the solar system, suggesting the new findings are reliable. About ten thousand dust particles were analyzed, with complex organic matter found in about one percent of them.
“It is the first ever detection of complex organics coming from an extraterrestrial waterworld,” according to Postberg.
“It was kind of a needle in a haystack problem,” he noted.
While data from Cassini has turned up organic matter before, the current findings show much larger fragments that could only have come from chemical processes such as those that occur with organic life, according to the European Space Agency (ESA). They may have come from hydrothermal processes occurring deep slow the surface of the moon, according to Postberg.
“In my opinion the fragments we found are of hydrothermal origin, having been processed inside the hydrothermally active core of Enceladus: in the high pressures and warm temperatures we expect there, it is possible that complex organic molecules can arise,” Postberg explained.
However, there is a possibility they could have come from another source, such as meteorites.
“We cannot decide this hundred-million-dollar question, but it certainly shows that something is going on there, that complex organic chemistry is happening and that we can probe it from space,” he added.
The ESA noted:
“This is the most recent in a long series of discoveries made by Cassini that have been painting Enceladus as a potentially habitable water-world.”
The mission, which was a joint venture between NASA, ESA, and Italy’s space agency, ended last year, when the craft descended into Saturn’s atmosphere.