New Problem Will Add New Tasks To Already Complicated
Mission
NASA will delay its mission to the Hubble Space Telescope until
next year, after the orbiting observatory suffered a failure of its
command and data-handling system Saturday night.
The New York Times reports the problem lies with a transmission
channel on the Hubble Control Unit/Science Data Formatter, one of
many such systems used to relay data from Hubble to the ground,
where it is assembled into images. That channel failed, causing the
telescope to revert to a safe mode... stopping all further data
collection.
That failure has stopped the flow of Hubble's stunning
deep-space images. While NASA hopes to have a backup channel up and
running later this week, a permanent repair will require a new
series of tasks for which the Atlantis crew has not been
trained.
Early Monday afternoon, NASA announced that the launch has been
moved from October 14 to sometime in 2009, possibly as early as
February. The delay will be needed to test replacement parts, and
train the crew for the installation.
The planned STS-125 mission was already one of the most
complicated and potentially dangerous in the history of the shuttle
program. The crew has already been training for two years to swap
out worn circuit boards inside the telescope's Advanced Camera for
Surveys and the Space Telescope Imaging Spectrograph. When Hubble
was launched 18 years ago, designers didn't envision it remaining
in use this long, and the circuits being replaced were not designed
for replacement in orbit.
Fortunately, the repair itself may not be so complicated -- at
least, relative to other tasks already on the STS-125 crew's
massive "to-do" list. The faulty part is attached to the inside of
a bay the astronauts will need to access anyway, and it's attached
by just 10 bolts.
"We think it's a relatively straightforward activity," said
Preston Burch, who manages the Hubble program at NASA's Goddard
Space Flight Center. He added discussions are now underway as to
whether or not the channel repair will bump other tasks from the
Hubble repair mission. It's possible a camera repair planned for
two spacewalks may be accomplished in one, which would free up that
slot for the relay fix.
"This may be a doable thing, that we can have our cake and eat
it too," Burch said.
It's possible that, on paper anyway, the on-orbit repair may be
less complicated than the process NASA must undergo to activate the
backup channel. Instructions on how to accomplish that are buried
deep in the Hubble's owner's manual, so to speak... and the
hardware used for the channel backup on Hubble has sat dormant for
almost two decades.