This
story was updated at 2:03 a.m. EST.
CAPE
CANAVERAL, Fla. - Astronauts aboard NASA's shuttle Atlantis are converting their
spacecraft back into a 100-ton glider today as they gear up for a planned
Wednesday landing.
Shuttle
commander Stephen Frick and pilot Alan Poindexter will fire Atlantis' thrusters
and test vital systems to ensure their spacecraft is ready to once again fly
through the Earth's atmosphere.
"We're
looking forward to getting home, and we're headed home now," Frick said after
Atlantis undocked
from the space station early Monday.
Atlantis'
seven-astronaut crew is due to land at 9:07 a.m. EST (1407 GMT) on a runway at
NASA's Kennedy Space Center in Cape Canaveral, Fla., here to conclude a successful
13-day mission to the International Space Station (ISS). The astronauts delivered the European Space Agency's (ESA) 1.4 billion
euro ($2 billion) Columbus laboratory to the ISS and swapped out one member of
the station's three-person crew.
"This
mission has gone extremely well," said Mike Sarafin, NASA's lead shuttle flight
director for Atlantis' spaceflight.
Engineers did
tackle a glitch overnight with heaters for four of Atlantis' aft-mounted
vernier thrusters used for attitude control. The heaters appeared to have
failed, but the glitch does not pose a safety concern for the shuttle crew's
landing, NASA officials said. The shuttle has a total of 44 thrusters that make
up its reaction control system.
"They are small
attitude control jets and they are not used during deorbit maneuvers," said
NASA mission commentator Lynette Madison. "There are no power or propellant
concerns."
Mission Control
radioed the Atlantis astronauts early today with an update on the glitch, adding that the crew may fly some unplanned maneuvers to keep the unheated thrusters from growing too cold.
"Thanks a lot for
those words," said Frick, whose crew awoke to the song "Always Look on the
Bright Side of Life" from the musical "Spamalot" - a tune chosen especially for
him - this morning. "We kind of figured we would be down [vernier jets] from now on but it is
good to hear we don't have any power or prop concerns."
Sarafin
said the shuttle astronauts and Mission Control accomplished all of their goals
despite some major changes, including the unexpected
illness of German astronaut Hans Schlegel, of the ESA, that kept him from
participating in one of the mission's
three spacewalks and added a day to the spaceflight.
"I couldn't
be prouder of them," Sarafin
said of the Atlantis crew and flight controllers on Earth. "We learned that we
had a good process in place."
Atlantis
has four landing opportunities on Feb. 20; two at KSC and two others at a
backup runway at California's Edwards Air Force Base. NASA hopes to land
Wednesday to give the U.S. military more time to shoot
down an ailing spy satellite laden with a half-ton of toxic hydrazine
rocket fuel.
"Generally,
the weather looks favorable at the Kennedy Space Center," Sarafin said, adding that mission
managers were drawing up a landing strategy on Monday.
Engineers
were also analyzing imagery from the Atlantis crew's final inspection of their
spacecraft's heat shield late to seek out any new damage from micrometeorites
or orbital debris during the mission. The orbiter was already cleared of any
concerns related to launch debris last week.
Gravity's
embrace
Atlantis astronauts
will spend time stowing away final bits of cargo and setting up a recumbent
seat for their newest crewmember - U.S. astronaut Dan Tani - who is returning
to Earth after a four-month flight to the ISS.
Tani joined
the station's Expedition 16 crew during NASA's last shuttle flight in late
October and originally hoped to return home in mid-December. But delays to
Atlantis' current mission added an extra two months to his orbital trek.
The
recumbent seat, which will allow Tani to weather Atlantis' landing in a
reclining position, is designed to ease his return to Earth's gravity after
months of weightlessness.
"I've been
working out on the treadmill quite a bit," Tani said of his preparations,
adding that past long-duration crewmembers have found the exercise regime
helpful. "Other than that, there's not really a lot much more preparation that
I can really do."
Tani's
replacement, ESA astronaut Leopold
Eyharts of France, launched aboard Atlantis on Feb. 7 and stayed aboard the
station to continue the commissioning of the Columbus laboratory until late
March.
"I'd like
to say that Dan is a great guy," Eyharts said before Tani left the station. "I
hope that in a few weeks, we'll be able to do 1/100th of what he is able to do
today."
NASA is
broadcasting Atlantis' STS-122 mission live on NASA TV. Click here for SPACE.com's
shuttle mission coverage and NASA TV feed.
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