On October 28, 2015, NASA steered their Cassini spacecraft past the south pole of Saturn's moon Enceladus. The idea was to use Cassini's dust analyzer to sample the plumes of water that regularly erupt from the south polar region (above) and see if anything could be learned about Enceladus' buried ocean. NASA cautioned at the time that Cassini's equipment was not designed for this task, so it might not work very well, plus the spacecraft's speed at closest approach would be about 17.7 kilometers/second (39,000 mph), not exactly ideal for sampling. They also warned that it might take "some time" for results to be made available.
They weren't kidding about the long wait. The first serious study of this study was finally published yesterday in Nature astronomy.
The results are interesting but not mind-blowing. Besides the small organic molecules everyone expected (methane, ethane), there were some larger finds: benzene or aryl rings, and what appeared to be compounds that also included Oxygen or Nitrogen; they especially think they may have found Benzyl methyl ether.
The discovery of these molecules, if that is indeed what Cassini found (again, the instrument was not designed for this), shows that the ocean contains organic molecules and has some interesting chemistry. But none of this points toward living organisms.
Again, though, this sample was collected in space by a spacecraft moving very fast and analyzed by an instrument not designed to look for larger organic molecules. So these findings in no way rule out life. But they don't make me believe.
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