An X-Ray Measurement of Titan’s Atmospheric Extent from Its Transit of the Crab Nebula

  title={An X-Ray Measurement of Titan’s Atmospheric Extent from Its Transit of the Crab Nebula},
  author={Koji Mori and Hiroshi Tsunemi and Haruyoshi Katayama and David N. Burrows and Gordon P. Garmire and Albert E. Metzger},
  journal={The Astrophysical Journal},
  pages={1065 - 1069}
Saturn's largest satellite, Titan, transited the Crab Nebula on 2003 January 5. We observed this astronomical event with the Chandra X-Ray Observatory. An "occultation shadow" has clearly been detected and is found to be larger than the diameter of Titan's solid surface. The difference gives a thickness for Titan's atmosphere of 880 ± 60 km. This is the first measurement of Titan's atmospheric extent at X-ray wavelengths. The value measured is consistent with or slightly larger than those… 

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