National Science Academy Urges NASA to Launch Astronauts to Hubble

National Science Academy Urges NASA to Launch Astronauts to Hubble
Ref: http://abcnews.go.com/US/wireStory?id=311613


CAPE CANAVERAL, Fla. Dec 8, 2004 -- NASA should use astronauts,
not a robot, to try a crucial life-prolonging mission to the acclaimed
Hubble Space Telescope one last time, a National Academy of Sciences
panel concluded Wednesday.

Using a robot would be highly uncertain, costly and could take too
long, the committee of scientists, engineers and astronauts said. But
NASA's chief has vowed that as long as he is in charge, he will not
risk astronauts just to keep the 14-year-old telescope beaming back
breathtaking snapshots of the cosmos for another five years.

NASA Administrator Sean O'Keefe has repeatedly contended that a Hubble
mission would be riskier to the astronauts than a shuttle flight to the
international space station. However, the National Academy of Sciences
committee found little difference in risk.

"The committee finds that the difference between the risk faced by the
crew of a single shuttle mission to ISS already accepted by NASA and
the nation and the risk faced by the crew of a single shuttle servicing
mission to HST, is very small," the committee wrote in its 135-page
congressionally requested report.

"Given the intrinsic value of a serviced Hubble, and the high
likelihood of success for a shuttle servicing mission, the committee
judges that such a mission is worth the risk."

George Washington University's John Logsdon, a member of the board that
investigated the Columbia accident that killed seven astronauts, said
"there is a pretty clear-cut answer" to all of this based on the
academy's findings and an Aerospace Corp. study due out any day that
also dismisses a robotic mission as a viable option.

The answer, Logsdon said, is to immediately cancel the robot plan,
proceed toward a shuttle mission while continuing to assess its safety,
and wait as long as possible before deciding whether to launch
astronauts a fifth and final time to the Hubble.

"Whatever else you can draw from it, it makes a pretty strong case
against investing over a billion dollars in a robotic servicing mission
or more," Logsdon said. The Aerospace Corp. has estimated a robotic
effort could cost $2 billion, about the same as the cost of sending
astronauts and would have only a 50-50 chance of success.

NASA had no immediate comment on the academy's findings, but on Tuesday
reiterated in a statement it would press ahead toward a possible
robotic mission and make a final decision next summer.

In its report, based on six months of analysis, the 21-member National
Academy of Sciences committee recommended that a shuttle servicing
mission occur as soon as possible once the grounded fleet is back in
operation possibly as early as the seventh post-Columbia flight. At
that point, critical shuttle missions for maintaining the space station
will have been accomplished, the panel said.

The committee expressed concern that some of the telescope's equipment
could degrade so much over the next few years that the observatory
would be impossible to fix or could not be safely steered into an ocean
grave. NASA's own estimates put the end of scientific observations at
2007 or 2008, barring any intervention.

It's also possible that a robot wouldn't be ready in time to save
Hubble. Or the two-armed metalman might not be able to latch onto
Hubble and perform all the necessary repairs, the committee said. It
could even wreck the observatory.

Such activities "have no precedent in the history of the space program"
and have a low chance of success, the group noted.

The committee expressed skepticism that such a complicated robotic
mission could be launched within the 3 1/2 years proposed by NASA.

"The design of such a mission, as well as the immaturity of the
technology involved and the inability to respond to unforeseen
failures, make it highly unlikely that NASA will be able to extend the
scientific lifetime of the telescope through robotic servicing," said
committee chairman Louis Lanzerotti, a solar-terrestrial research
professor at the New Jersey Institute of Technology.

There is about a 30 percent chance of mission risk for a shuttle
servicing mission, given the objective of at least three extra years of
Hubble observations, versus 80 percent for a robotic mission, the
committee said.

The goal of any repair mission would be to install fresh batteries,
gyroscopes, fine-guidance sensors, and two powerful new cameras that
could make Hubble more productive than ever.

"Hubble's promise for future discoveries following a fifth servicing
mission would be comparable to the telescope's promise when first
launched," in 1990 by shuttle Discovery, the committee concluded.

The committee stressed that a robotic mission should be pursued solely
to bring Hubble down at the end of its scientific life which it noted
will be longer if astronauts intervene.

NASA has agreed that failing all else, it will use a robotic spacecraft
to steer Hubble into the ocean by 2013.