Despitefacing looming technical problems with a launch vehicle and assembly crane,NASA officials said in a telephone conference today that they are intent on aJuly 7 launch of the Dawn mission.
If thelaunch vehicle and assembly crane aren?t repaired, however, the U.S. space agency faces a ?traffic jam? into space that could cost around $25 million.
Roughweather caused mechanical difficulties in components attached to the launchvehicle during its transportation, a NASA official said.
Todd May,the deputy associate administrator for programs at NASA headquarters in Washington, said both the asteroid-belt-exploring Dawn and Mars-boundPhoenix missions are very sensitive to launch changes. To reach theirtargets, eachmust leave Earth within a defined window of time.
?They?reboth planetary, so they have limited launch windows,? May said. ?It?s a hardwindow constraint to get (Phoenix) off by Aug. 25,? he continued, so anymovement of the Dawn launch window could also interfere with Phoenix?slaunch?as well as the STS-118shuttle mission, expected to launch on Aug. 7.
Inaddition to the launch problems, one of Dawn?s solar panels was damaged whileat NASA?s Kennedy Space Center during processing. On June 18, NASA saidtechnicians repaired damage, which was caused by an ?errant tool.?
The Dawnmission team will decide on July 2 whether they will launch Dawn July 7. Mayexplained that scrubbing the launch would cost around $25 million, but said theteam is moving ?full steam ahead? for a launch next Saturday.
?To someextent there?s no looking back,? he said of an agreement to launch. ?We will bewatching the weather closely and by that time have the launch vehicle issuesout of the way.?
NASA hopesto use Dawn to investigate twoleftover chunks of the early solar system. Ceres was once called thelargest asteroid and is now re-labled as a dwarf planet. The other target:asteroid Vesta. Both objects reside in the asteroid belt between Mars andJupiter.
The twobodies share similar properties with Earth, and astronomers believe Ceres, atabout 590 miles wide, might harborice beneath its dusty shell. Vesta is a mostly dry rock roughly 330 milesin diameter.
If all goesas planned, the spacecraft will first orbit Vesta in 2011 and then Ceres in2015. At each stop, Dawn will collect detailed information and photographs ofeach rock, such as their shape, size, composition and even clues to theirinternal histories. Scientists think such information about Earth?sasteroid-belt cousins could reveal clues as to how the solar system formed.