The INMS instrument detected mostly water vapor, as well as traces of molecular nitrogen, carbon dioxide, and trace amounts of simple hydrocarbons such as methane, propane, acetylene and formaldehyde. The plumes' composition, as measured by the INMS, is similar to that seen at most comets. "Cassini" also found traces of simple organic compounds in some dust grains, as well as larger organics such as benzene (), and complex macromolecular organics as large as 200 atomic mass units, and at least 15 carbon atoms in size.