• Introduction



      The Comet Nucleus Tour, or CONTOUR, mission was to study two very different comets as they made their periodic visits to the inner solar system.  It was the first mission designed to study both the physical and chemical properties of comets.

      At each comet flyby, the spacecraft was to get as close as 60 miles to the comet nucleus to capture high resolution pictures, perform detailed compositional analyses of gas and dust, and determine the comet's precise orbit.  This information would dramatically improve our knowledge of comet nuclei and their diversity.



      Mission Management

      The CONTOUR mission was managed for NASA and built by The Johns Hopkins University Applied Physics Laboratory in Laurel, MD.  The Principal Investigator was Dr. Joseph Veverka of Cornell University.

      Dr. Joseph Veverka
      Dr. Joseph Veverka
      Principal Investigator

  • Science Objectives
    • CONTOUR's targets were comets Encke and Schwassmann-Wachmann-3. Encke is very old, giving off little gas and dust; it is one of the most studied comets.  "SW3" split into pieces when it passed close by the Sun in 1995 so fresh, new surfaces were expected. CONTOUR's main objectives were to:

      Assess the diversity of comets

      Study in unprecedented detail the processes by which comet nuclei work

      Determine for the first time the differences between Kuiper Belt and Oort Cloud comets


      Boeing Delta II rocket
      The Boeing Delta II rocket carrying CONTOUR streaks across the night sky above launch pad 17-A, Cape Canaveral Air Force Station, Florida.


  • Details
    • CONTOUR spacecraft
      Two objects possibly belonging to the CONTOUR spacecraft.

      ©2002 The Spacewatch Project, Lunar and Planetary Laboratory, The University of Arizona.

      CONTOUR launched from Cape Canaveral Air Force Station, Florida, on July 3, 2002. Unfortunately, six weeks after launch, on August 15, 2002, contact with the spacecraft was lost after a planned maneuver that was intended to propel it out of Earth orbit and into its comet-chasing solar orbit. Limited ground-based evidence at the time suggested the spacecraft split into several pieces.  Attempts to contact CONTOUR were made through December 20, 2002, when NASA and The Johns Hopkins University Applied Physics Laboratory concluded the spacecraft was lost.

      NASA convened a Mishap Investigation Board to examine the processes, data, and actions surrounding the events of August 15; search for proximate and root causes; and develop recommendations that may be applicable to future missions.

      After an extensive investigation, the board identified four possible causes for the failure but concluded the probable proximate cause was structural failure of the spacecraft due to plume heating during the embedded solid-rocket motor burn.

      For more details on the mission profile, spacecraft, and subsystems, go to the National Space Science Data Center CONTOUR page.