Last autumn, when NASA's famous Cassini spacecraft was spiraled against its final, deadly descent in Saturn's cloud, astronaut Morgan Cable could not help tearing a school bus size scale, which became a victim of his own success.
Early in his mission, Cassini discovered that he moved over Saturn's ice-covered moon Enceladus, discovered rays of ice and saltwater from cracks in the southern pole – a sign that the body contained an underground sea that could end life. When the orbite began to run on fuel, it entered Saturn instead of risking an obscure obscurity that could contaminate the potentially inhabited world.
Now, from space to space, spacecraft has offered even a prize for researchers. New analysis of Cassini data suggests that the oily plums shoot into space containing complex organic compounds ̵
That an aging orbiter not intended for life detection could recognize these molecules – which are among the largest and most complex organic substances found in the solar system make the icy moon an even more exciting goal in the search for outer life, says Cable , a researcher at the Jet Propulsion Laboratory who was not involved in the new research.  "This is a powerful study with a powerful result," she said.
The results published in the Nature journal are based on data collected by two Cassini instruments – Cosmic Dust Analyzer and Ion and Neutral Mass Spectrometer – as spacecraft flew through Saturn's outermost ring and Enceladus plumes (pronounced "en-SELL-a -dus ").
Previous research using these instruments has ected small organic molecules like methane, which consists of four hydrogen atoms bound to a single carbon. INMS has also detected molecular hydrogen – a chemical characteristic of hydrothermal activity that provides vital fuel for microbes living around sea-level valves.
The molecules reported in the new Nature Paper are "magnitudes" larger than seen earlier, according to leading author Frank Postberg, a planet scientist at the Heidelberg University in Germany. There were stable carbon structures called aromatic substances as well as chains of carbon atoms linked to hydrogen, oxygen, perhaps even nitrogen.
Some of the molecules detected by CDA were so large that the instrument could not analyze them. This suggests that the organic Cassini found only are fragments of even larger compounds, Postberg said. It may well be large polymers – many segmented molecules like those that make up DNA and proteins – are still waiting to be detected.
"We astrobiologists are excited about larger molecules and the kind of things because it means something is based on itself and getting more complicated," said Kate Craft, a planet scientist at Johns Hopkins University Applied Physics Laboratory, who was not involved in the research.
The molecules Cassini has discovered can be produced abiotic – without the involvement of life. But they are also the types of compounds that microbes on Earth like to eat, and they can even be byproducts of microbial metabolism.
"Put that way if they did all these tests and did not see these larger molecules, (Enceladus) does not seem to be habitable," said Craft. "But these findings … are reason to say," Hi, we have to go back there and take a lot more data. ""
Researchers believe that Saturn's gravity affects and bends the porous rocky material at Enceladus's core that generates heat. That heat allows for chemical interactions between the salty sea and the seabed. On earth, such water-glass interactions provide fuel for chemical groups – organisms that get energy by breaking down chemicals in their environments – and supporting large ecosystems in the deepest, darkest depths of the ocean.
Postberg and his colleagues suggest that the organic molecules generated in the Enceladus sea depth will eventually flow to the surface, forming a thin film just below the ice crust of the planet.
Earth's oceans are covered in a similar film, they note – a millimeter thick blanket of small microbes and organic substances that serve as an important interface between sea and sky. Research shows that this layer helps to drive weather; As bubbles break from breaking waves, particles from the film are lifted into the air, giving them a core around which water can condense to form clouds and fog.
A similar process on the surface of Enceladus ocean can form ice crystals with organic cores, Postberg said. These grains are then sucked up through cracks in the moonstone called "tiger strips" and then thrown into the vacuum in space.
The Enceladus plumes are extremely thin – more like a thin veil than a beam from a fire hose – and researchers have questioned whether a spacecraft flying through the spray could gather enough organic substances to draw conclusions about their origin.
This result, Postberg, shows that Enceladus "is kind to us and delivers its organic inventory in high concentrations in space."
Cable is a deputy project scientist for a concept called Enceladus Life Finder, who would use more advanced instruments than those on Cassini to try the plume during a series of airfields. The mission has not been funded by NASA, and the space agency has no development projects to return to Enceladus.
She, Postberg and Craft expressed hope that the latest result would give interest in a new mission to the ugly moon. 19659002] "Enceladus shouts at us that it has all the ingredients for life as we know it: water, chemistry, organic," said Cable. "We have to go back."