The robotic Cassini probe detected propylene on the moon marking the first time the chemical has been found in outer space. Titan's atmosphere is brownish and freezing temperatures can plummet to -180°C.
NASA scanned the moon's air using Cassini's Composite Infrared Spectrometer (CIRS) which measures the heat radiation emitted as infrared light. NASA likened the process to "the way our hands feel the warmth of a fire."
Propylene was the first chemical identified using CIRS. It was found at various altitudes throughout the lower levels of the soupy hydrocarbon fog found in the moon's noxious skies.
"This chemical is all around us in everyday life, strung together in long chains to form a plastic called polypropylene," said Conor Nixon, a planetary scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of a paper describing the findings.
"That plastic container at the grocery store with the recycling code 5 on the bottom - that's polypropylene."
Scientists said the success of the findings would boost their "confidence that [they] will find still more chemicals long hidden in Titan's atmosphere."
"I am always excited when scientists discover a molecule that has never been observed before in an atmosphere," said Scott Edgington, Cassini's deputy project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. "This new piece of the puzzle will provide an additional test of how well we understand the chemical zoo that makes up Titan's atmosphere."
The Cassini-Huygens mission is a joint project of NASA, the European Space Agency and the Italian Space Agency.