To the astonishment of the project's science team, the robotic asteroid probe,
known as Dawn, was axed on March 2 despite being cleared by an independent review
team investigating cost overruns triggered by technical problems.
Dawn was being designed to explore the two largest known asteroids in the
primary asteroid belt, which lies between Mars and Jupiter.
Scientists want to study the asteroids, which do not resemble each other,
to learn more about how the solar system was created.
NASA had already spent about $200 million of the spacecraft's estimated $289-million
budget when it canceled the project. Another $84 million was allotted for the
probe's launch vehicle and related launch services.
Cancellation costs would have added $14 million. NASA put the project on hold last October and ordered an independent team
to investigate the projected $40-million budget overrun.
NASA said most of the problems centered on the probe's innovative ion engine,
which unlike traditional chemical-burning motors, generates speed by expelling
a stream of electrically-charged particles, or ions, stripped from xenon gas.
The review team recommended NASA spend the extra funds but the agency, which
has been struggling to pay for a myriad of programs, canceled the program on
March 2.
"We had a very gut-wrenching decision and significant management and technical
problems to overcome," said Colleen Hartman, NASA's deputy associate administrator
for science, in a teleconference with reporters on Monday.
Program managers appealed the decision and, on Monday, NASA changed its mind.
Dawn is now scheduled to launch in the summer of next year and it should
reach its first target in 2011.
NASA agreed to reinstate funding and added about $70 million more to cover
the project's overrun as well as additional costs associated with stopping work
on the mission for five months.
"I'm glad there were no fatal technical flaws, and that they were able to
find the money after all," said Mark Sykes, director of the Arizona-based Planetary
Science Institute and member of the Dawn science team. "But this is not a good
way to do business."
