The Comet Nucleus Tour (CONTOUR) was a NASA Discovery-class space probe that failed shortly after its July 2002 launch. It was the only Discovery mission to fail.
Artist impression of CONTOUR approaching a comet.
The CONTOUR spacecraft at the Kennedy Space Center in May 2002, being prepared for launch.
Long-exposure photograph of the launch of CONTOUR from Cape Canaveral on July 3, 2002.
The Discovery Program is a series of Solar System exploration missions funded by the U.S. National Aeronautics and Space Administration (NASA) through its Planetary Missions Program Office. The cost of each mission is capped at a lower level than missions from NASA's New Frontiers or Flagship Programs. As a result, Discovery missions tend to be more focused on a specific scientific goal rather than serving a general purpose.
Depictions of the Lucy and Psyche missions
Asteroid Eros regolith, as viewed by Discovery's NEAR Shoemaker mission
Asteroid 253 Mathilde
Mars Pathfinder's view of Ares Vallis