Ion Neutral Mass Spectrometer Results from the First Flyby of Titan

The Cassini Ion Neutral Mass Spectrometer (INMS) has obtained the first in situ composition measurements of the neutral densities of molecular nitrogen, methane, molecular hydrogen, argon, and a host of stable carbon-nitrile compounds in Titan's upper atmosphere. INMS in situ mass spectrometry has also provided evidence for atmospheric waves in the upper atmosphere and the first direct measurements of isotopes of nitrogen, carbon, and argon, which reveal interesting clues about the evolution of the atmosphere. The bulk composition and thermal structure of the moon's upper atmosphere do not appear to have changed considerably since the Voyager 1 flyby.

[1]  Andrew Wilson.  Huygens : science, payload and mission , 1997 .

[2]  T. Owen,et al.  Millimeter and Submillimeter Heterodyne Observations of Titan: Retrieval of the Vertical Profile of HCN and the12C/13C Ratio , 1997 .

[3]  S. Atreya,et al.  Evolution of a Nitrogen Atmosphere on Titan , 1978, Science.

[4]  Thomas J. Ahrens,et al.  Global earth physics a handbook of physical constants , 1995 .

[5]  P. J. Schinder,et al.  Titan's Atmospheric Temperatures, Winds, and Composition , 2005, Science.

[6]  A. Coustenis,et al.  Titan's atmosphere from voyager infrared observations: I. The gas composition of Titan's equatorial region , 1989 .

[7]  C. McKay,et al.  High-temperature shock formation of N2 and organics on primordial Titan , 1988, Nature.

[8]  J. Lunine,et al.  Thermodynamics of clathrate hydrate at low and high pressures with application to the outer solar system , 1985 .

[9]  Michael J. Whiticar,et al.  Carbon and hydrogen isotope systematics of bacterial formation and oxidation of methane , 1999 .

[10]  Y. Yung,et al.  Isotopic fractionation of stratospheric nitrous oxide , 1997, Science.

[11]  William H. Press,et al.  Numerical recipes , 1990 .

[12]  J. Lunine,et al.  Clathrate and Ammonia Hydrates at High Pressure: Application to the Origin of Methane on Titan , 1987 .

[13]  D. Strobel,et al.  New perspectives on Titan's upper atmosphere from a reanalysis of the Voyager 1 UVS solar occultations , 2004 .

[14]  Bruce Fegley,et al.  The Planetary Scientist's Companion , 1998 .

[15]  E. Herbst,et al.  The possibility of nitrogen isotopic fractionation in interstellar clouds , 2000 .

[16]  R. Kallenbach,et al.  Isotopic Composition of Solar Wind Nitrogen: First In Situ Determination with the CELIAS/MTOF Spectrometer on board SOHO , 1998 .