This story was updated at 9:25 p.m. EDT.
HOUSTON - While
spacewalking astronauts struggled with a stuck bolt on the Hubble Space
Telescope Thursday, scientists on Earth were on edge as it seemed that years of
preparation to make the observatory more powerful than ever might slip away.
The Atlantis
shuttle astronauts were eventually victorious in their battle against the bolt and
left the 19-year-old Hubble with a powerful
new camera eye, but the glitch kept scientists on edge until the very end.
"I can tell you that I'm five years older now than when I came to work this
morning," said a relieved Dave Leckrone, Hubble's senior project scientist, after
the spacewalk.
A
recalcitrant bolt
That the
orbital drama unfolded around the storied Wide Field Planetary Camera 2, an accomplished
instrument that has produced the bulk of Hubble's most
recognized images of the universe since its 1993 installation, made it that
much more frustrating. That camera is destined to come back to Earth and be
celebrated in a museum.
But a bolt
used to latch the camera down refused to budge and it almost looked like the instrument
- which still works fine - might have to stay put. Its long-awaited replacement
- the new $132 million Wide Field Camera 3 - would then have to return home
before it had a chance to shine.
In the end,
after all other backup tools failed, it came down to an astronaut's brute
strength and delicate touch.
Spacewalker
Andrew Feustel put a little extra oomph in his ratchet to loosen the bolt, but
was careful not to overdo it and shear it off. He and fellow spacewalker John
Grunsfeld then seamlessly went on to install the new camera, which scientists
hope will allow Hubble to see baby galaxies forming 500 million years after the
birth of the universe. The universe is 13.7 billion years old. The astronauts also
replaced a vital computer data unit among other tasks.
"There was
just a huge outburst, a rush of elation and emotion when that came loose,"
Leckrone told reporters here at NASA's Johnson Space Center. "I just hope the
rest of the mission is a bit smoother."
And,
Leckrone added, there's a lot more mission to go.
Ambitious
work ahead
Thursday's
successful spacewalk marked the first in a marathon of five back-to-back excursions by the
seven astronauts aboard Atlantis. The once-canceled mission is the fifth and final
shuttle flight to overhaul Hubble
before NASA retires its three-orbiter fleet next year.
Working in
two-man teams on alternating days, the shuttle's four spacewalkers hope to
install two new instruments, perform delicate maintenance work and attempt
unprecedented repairs on two instruments that were never designed to be fixed
in space.
For the
repairs in particular, there are no guarantees, NASA has said. Everything
required just to attempt them - including 116
new tools invented from scratch - is completely new.
"We had a
few rough spots today and we had some emotional ups and downs," said Hubble program
manager Preston Burch, of NASA's Goddard Space Flight Center in Greenbelt, Md.,
that oversees the telescope. But Burch said he's confident Atlantis' crew will
have a full five spacewalks in which to upgrade Hubble.
The mission
was ambitious to begin with, and with the intricate and uncertain repair
attempts still ahead, it should only get harder, mission managers said.
On Friday, astronauts
will attempt the delicate work of replacing Hubble's gyroscopes, which keep the
telescope pointed properly, and batteries. A spacewalker will have to go inside
Hubble with only a few inches of clearance.
On Saturday,
astronauts will try to fix Hubble's broken main camera - the Advanced Camera
for Surveys. It has been broken since 2007 and astronauts will try to revive by
removing 32 screws and replacing faulty electronics cards while clad in bulky
spacesuits.
Then one
day later, on Sunday, spacewalkers will attempt the unprecedented fix of a
powerful spectrograph that will require the removal of 111 fasteners and the
replacement of an electronics card. The last spacewalk on Monday will give Hubble
another fresh set of batteries, extra thermal insulation and a new guidance
sensor.
"Today was
a speed bump, but two days from now is going to be the hold your breath time
for most of the day," Leckrone said.
SPACE.com
is providing continuous coverage of NASA's last mission to the Hubble Space
Telescope with senior editor Tariq Malik in Houston and reporter Clara
Moskowitz in New York. Click
here for mission updates, live spacewalk coverage and SPACE.com's
live NASA TV video feed.
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