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The spacecraft set to provide the closest look ever at a comet nucleus was shipped today from The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland — where it was designed and built — to NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for its next round of prelaunch testing.

Scheduled to launch July 1 from Cape Canaveral Air Force Station, Florida, the Comet Nucleus Tour (CONTOUR) spacecraft spent the past 10 days in an APL vibration test lab, where engineers checked the structural integrity of the eight-sided, 6-by-6 foot craft aboard a large shake table.

“The vibration tests at APL went very well,” says CONTOUR Project Manager Mary C. Chiu of the Applied Physics Lab. “The spacecraft is in great shape and we’re ready to move on to the next stage.”

At Goddard the spacecraft will undergo spin tests; acoustic tests, designed to simulate the noise-induced vibrations of launch; and thermal vacuum tests, which replicate the harsh conditions of deep space. In late April, CONTOUR will be transported to Kennedy Space Center/Cape Canaveral and prepared for launch aboard a three-stage, Boeing Delta II launch vehicle.

“By the time CONTOUR launches it will have been thoroughly tested,” says Michael J. Colby, CONTOUR lead integration and test engineer at APL. “You have to be extremely confident that the spacecraft will be OK when it’s mounted on that Delta.”

After launch, the solar-powered CONTOUR will visit at least two comets as they travel through the inner solar system. From as close as 60 miles (100 kilometers), the spacecraft will take the most detailed pictures ever of a comet’s nucleus; map the types of rock and ice on the nucleus; and analyze the composition of the surrounding gas and dust. CONTOUR’s targets include comet Encke in November 2003 and Schwassmann-Wachmann 3 in June 2006, though the spacecraft can also be sent toward an as-yet-undiscovered comet. The data will provide clues into the similarities and differences between comets.

CONTOUR is the next launch in NASA’s of low-cost, scientifically focused missions. The Applied Physics Laboratory manages the mission for NASA and will operate the spacecraft. Dr. Joseph I. Veverka of Cornell University, Ithaca, New York, is CONTOUR’s principal investigator and heads a science team of experts from institutions around the globe. APL, Goddard Space Flight Center and von Hoerner & Sulger, Schwetzingen, Germany, built CONTOUR’s scientific instruments; NASA’s Jet Propulsion Laboratory, Pasadena, California, will provide navigation support.

For more information, visit the CONTOUR Web site at .