NASA delays repair mission to
Hubble telescope
By MARCIA DUNN
AP Aerospace Writer
CAPE CANAVERAL, Fla. (AP) -- NASA said Monday it is delaying its
mission to the Hubble Space Telescope until next year because of a serious
breakdown of the observatory in orbit.
Space shuttle Atlantis had been scheduled to blast off in just two weeks,
but an unexpected problem with the Hubble appeared on Saturday night when
the telescope stopped sending science data.
That potentially means a new repair issue for the astronauts to confront -
one that they haven't trained for and never anticipated.
The abrupt, mysterious failure of the command and data-handling system for
Hubble's science instruments means that the telescope is unable to capture
and beam down the data needed to produce its stunning deep space images.
Early Monday afternoon, NASA announced that the Oct. 14 launch had been
postponed until at least early next year, possibly February. Each month's
delay will cost the Hubble program about $10 million.
It could have been far worse, said NASA's science chief, Ed Weiler.
"Think about if this failure had occurred two weeks after the servicing
mission, we had just put two brand new instruments in and thought we
extended the lifetime for five, 10 years and this thing failed after the
last shuttle mission to Hubble," Weiler told reporters Monday evening.
"So in some sense, if this had to happen, it couldn't have happened at a
better time."
Hubble manager Preston Burch said the first step is to try to fix the
telescope by switching to a backup channel for the science instruments'
command and data-handling system, and allowing observations to resume. That
should take a week or two. Even if the effort succeeds as engineers suspect
it will, Burch and other officials still want to send up a replacement part
for the bad component.
That's because there would be no other options if that one last working
channel malfunctioned.
"Our plan right now is to take the delay and put up the new hardware ... so
that we can keep Hubble going for as long as possible," Weiler said. "If
we're going to spend the money and take all the risk involved in a shuttle
mission, we want to be sure that we leave Hubble as healthy as we possibly
can and potentially lasting for five or 10 more years."
It will take time to qualify the old replacement part; it was last used for
testing in 2001. The equipment won't be ready before January, which would
most likely mean a February launch, Burch said.
The replacement job would be relatively straightforward for the astronauts,
who have trained two years to carry out five Hubble repair spacewalks. The
work would take less than two hours and could be squeezed into one of the
already planned spacewalks.
Work already has begun to switch the telescope to the backup channel. It is
a complicated process; the backup channels on the various modules that must
be switched over have not been turned on since the late 1980s or early 1990,
right before Hubble was launched. Managers also want to assess all the
risks.
"This is a major event for Hubble," Burch said.
NASA officials stressed that the telescope is not in trouble; it's just that
it cannot send science information to ground controllers. That means NASA is
unable to receive the dramatic pictures Hubble is known for.
The mission by Atlantis and a seven-person crew - whenever it is - will be
the fifth and final servicing mission to Hubble.
Weiler said the latest problem is nothing compared with the flawed mirror
that left the telescope with blurred vision back in 1990. That trouble was
overcome by an astronaut repair team in 1993.
"Hubble has a habit of coming back from adversity, and the Hubble team ...
works miracles," Weiler said. "I'm not too concerned about this. We'll find
a way to get this fixed. Luckily, we've got a spare."
Now, Endeavour will be the next shuttle up, on a trip to the international
space station in mid-November. Endeavour is already at the launch pad; it
was supposed to serve as a rescue ship for Atlantis in case of trouble.
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