This graph shows data acquired by Cassini as it flew by Titan at an altitude of 1,200 kilometers (745 miles) on Oct. 26, 2004 - its closet approach yet to the hazy moon. The data is from Cassini's ion and neutral mass spectrometer, which detects charged and neutral particles in the atmosphere. The graph shows that the amount of light nitrogen in the atmosphere of Titan is much less than that around other planets. Scientists believe this nitrogen was lost over large geologic times scales for reasons that remain unknown.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The ion and neutral mass spectrometer team is based at University of Michigan, Ann Arbor.