Cassini Mission


    Descent Imager/Spectral Radiometer (DISR)

    The DISR instrument, designed at LPL by a team led by Research Professor Martin Tomasko, made a range of imaging and spectral observations using several sensors and fields of view. By measuring the upward and downward flow of radiation, the radiation balance (or imbalance) of the thick Titan atmosphere was measured. Solar sensors measured the light intensity around the Sun due to scattering by aerosols in the atmosphere. This permitted the calculation of the size and number density of the suspended particles. Two imagers (one visible, one infrared) observed the surface during the latter stages of the descent and, as the probe slowly rotated, built up a mosaic of pictures around the landing site. There was also a side-view visible imager that obtained a horizontal view of the horizon and the underside of the cloud deck. For spectral measurements of the surface, a lamp switched on shortly before landing that augmented the weak sunlight.

    Huygens Scientists Hold Final Science Meeting at UA | November 15, 2004
    UA Scientists Prepare for Huygens Descent on Titan - December 26, 2004
    Huygens Probe Lands with a 'Splat'; Mission Gets Off to a Bang | January 18, 2005
    Huygens Team Releases First Enhanced Mosaics of Titan | May 19, 2005
    Landing on Titan: The Movies | April 20, 2006
    UA Scientist Who Led Huygens Imaging to Give Public Lecture on 2nd Anniversary of Titan Landing | January 16, 2007

    Visual and Infrared Mapping Spectrometer

    The VIMS instrument on the Cassini spacecraft had several unique capabilities. It was able to identify the chemical composition of a surface, atmosphere, or Saturn’s rings by measuring the visible and infrared energy. VIMS was, in essence, a color camera that took pictures in 352 different wavelengths between 300 nm and 5100 nm. This range, coupled with the ability to discern different wavelengths (called spectral resolution), allowed the VIMS instrument to be able to very accurately quantify the light it detected. Do you know which wavelengths of light we can see? The visible spectrum falls between 400 nm and 700 nm, a small portion of the light that the VIMS instrument gathered. The VIMS instrument was operated from LPL by a team led by Professor Robert Brown.

    Map of Titan created by LPL Cassini VIMS Team
    VIMS Instrument Records at UArizona Special Collections
    UA's Cassini Scientists at First Close Titan Flyby - October 19, 2004
    Cassini Spies the Brightest Infrared Spot on Titan - May 17, 2005
    Titan's Enigmatic Infrared-Bright Spot Is Surface Make-Up - October 5, 2005
    Cassini's VIMS Detects Vast Polar Ethane Cloud on Titan - September 11, 2006
    Cassini Image Shows Saturn Draped in a String of Pearls - October 11, 2006
    Cassini's Infrared Camera Sees Tall Mountains on Saturn's Moon Titan - December 11, 2006
    Cassini Instrument Confirms Liquid Surface Lake on Titan - July 30, 2008
    Water Geysers on Saturn’s Moon - July 31, 2013
    After Farewell Kiss, Cassini Takes the Plunge - September 12, 2017
    Gas Giants’ Energy Crisis Solved After 50 Years | June 22, 2021