"This is the first definitive detection of the
plastic ingredient on any moon or planet,
other than Earth," NASA said.
A small amount of propylene was identified
in Titan's lower atmosphere by Cassini's
composite infrared spectrometer, which
measures heat radiation, the agency reported
in Monday's edition of the Astrophysical
By isolating the same signal at various
altitudes within the lower atmosphere,
researchers identified the chemical's unique
thermal fingerprint with a high degree of
confidence, NASA said.
"This chemical is all around us in everyday
life, strung together in long chains to form a
plastic called polypropylene," said Conor
Nixon, a scientist at NASA's Goddard Space
Flight Center in Greenbelt, Maryland, and
lead author of the paper.
"That plastic container at the grocery store
with the recycling code 5 on the bottom -
The chemical is also used to make car
bumpers and other consumer products.
The discovery could help scientists
understand the "chemical zoo" that makes up
Titan's hazy brownish atmosphere, said Scott
Edgington, Cassini's deputy project scientist
at NASA's Jet Propulsion Laboratory in
The Cassini-Huygens mission is a cooperative
project of NASA, the European Space Agency
and the Italian Space Agency.