Falling Wrench Hits Solar Panel, No Cells Broken

NASA is investigating a minor mishap affecting the delay-plagued Dawn spacecraft, although the target launch date of July 7 is unaffected.

On June 11, during a procedure to prepare the spacecraft for spin-balance testing, the back of a solar array panel was slightly damaged by a technician's tool. Media reports indicate the unspecified tool fell from a platform suspended above the probe.

Fortunatelt, no solar cells were broken, and NASA says the necessary minor repairs will be made this weekend.

Loading of xenon for the ion propulsion system was completed last week. Hydrazine, used for spacecraft control and maneuvering, was loaded aboard June 10. The spacecraft was then weighed and placed on a spin table for a series of spin tests that are currently under way.

Dawn will be mated to its associated upper-stage booster on June 21 and transported to Pad 17-B for mating to the Delta II on June 26.

At Pad 17-B, the operations to attach the Delta II solid rocket boosters to the first stage are complete. The second stage is planned to be hoisted atop the first stage on Friday.

This isn't the first glitch the Dawn team has suffered through this month. As ANN reported, a crane used to stack segments of the Delta II booster broke down, forcing NASA to bump Dawn's scheduled June 30 launch date by one week.

Frustrated mission planners may take some comfort, at least, that Dawn has come this far... as NASA cancelled the program outright in early 2006, before granting Dawn a reprieve weeks later after scientists protested.

Once it is eventually launched, Dawn will visit the asteroids Ceres and Vesta, contained in an asteroid belt between Mars and Jupiter. They are two of the largest such bodies in the solar system, and scientists hope the two heavenly bodies will reveal clues about the formation of the solar system.

FMI: http://dawn.jpl.nasa.gov/