Spacewalk success: space station gets new walk-in closet, Robonaut included
On Monday and Tuesday, spacewalking astronauts installed a new Italian-built cargo carrier that will provide storage for the International Space Station, after it is unpacked in coming weeks.
Houston — Welcome to your new home, Leonardo.
With a deft touch, astronauts Nicole Stott and Michael Barratt used the space station's robotic arm Tuesday morning to gingerly lift a 21-foot-long module from the orbiter's cargo bay and attach it to the International Space Station. For 10 years, the Italian-built module, dubbed Leonardo, has ferried goods to and from the space station; it is now the Permanent Multipurpose Module – a new walk-in storehouse for the orbiting outpost.
The space station was high over Turin, Italy, when controllers in Houston drove the final bolts home that joined the Italian-made module to the station. Fully loaded with station-bound cargo, the module tipped the scales at 13.5 tons.
The module, modified to survive the rigors of long-term exposure to space, will give the space-station crew nearly 2,500 cubic feet of additional, pressurized space for storage as well as for racks of science gear. For now, the silvery cylinder also is home to Robonaut 2, the upper half of a humanoid robot that designers hope will ultimately become a mobile, silent partner to the station's crew.
On Monday, the mission-management teams for the station and shuttle approved adding a day to Discovery's mission to allow the orbiter's crew to help unload the module and help stow supples throughout the rest of the station. The extra hands also will speed the process of getting rid of the packing material – now trash – that protected the module's contents from the intense vibrations of launch.
Astronauts will put the refuse in a Japanese unmanned cargo craft, known by its initials HTV. The craft is slated to leave the station shortly after Discovery does. The HTV and its trash will be destroyed as the craft reenters the atmosphere.
The installation of the module comes fresh on the heels of a successful spacewalk on Monday.
The tasks were all the more challenging because Bowen was a last-minute replacement for Tim Kopra, who was injured in a bicycle accident in January and so was scratched from the crew.
Bowen, no stranger to maneuvering in space, has taken part in five previous spacewalks, most recently during a shuttle mission last May. But he had only about a month to prepare for this mission's spacewalks, which the shuttle crew had spent some 10 months perfecting.
During training, astronauts who will perform the spacewalks – called "extra-vehicular activity," or EVAs, in NASA lingo – refine procedures to fit their particular work styles, explained Art Thomason, the lead spacewalk officer, during a briefing Monday evening.
"In this case, Tim helped develop those EVAs all along the way," he said. "With Steve coming in late, he really had to rely on Tim and his expertise to explain how he performed each task specifically."
Kopra was at the capsule-communicator console during Monday's spacewalk, to advise Bowen as the work progressed.
As if to make Monday's spacewalk even more interesting for Bowen, a software glitch in the station's robotic arm controls left the veteran space walker perched at the end of the arm – while he gripped an 800-pound, dryer-sized coolant pump.
The pump mysteriously failed last July, the station crew replaced it with a spare, and Bowen was moving the balky unit to a spot on the station's exterior where another shuttle crew can pluck it off and return it to Earth for evaluation.
At one point, controllers asked him how he was holding up. "I'm fine as long as it's not too much longer," Bowen replied.
Since the software glitch was localized to one work station – located in the cupola astronauts installed in February 2010 – the robotic-arm team shifted to a work station in the US Destiny laboratory.
The arm, Bowen, and the pump were soon moving again, having been stuck for less than half an hour altogether.
In addition to the pump-relocation job, Bowen and Drew added a foot of extra track to a mini rail line along one of the station's support trusses. The track allows space-walking astronauts to use a cart to move tools and parts along the truss when repairs are needed.
Dubbed "Message in a Bottle," the final task prompted controllers to inflict a musical pun on the space walkers: The classic-rock hit "Message in a Bottle," by the group Police, accompanied the astronauts as they moved along the station toward the spot where they snagged the sample, then ducked inside an air lock and shut the hatch.
In the end, Bowen and Drew – a space-walk rookie who became the 200th human to take part in an EVA – spent 6 hours and 34 minutes outside the station, a scant four minutes longer than planned.
Despite the glitches, the duo finished all of the tasks, including two so-called "get-ahead tasks" designed to lighten the load for future spacewalks. The space station's lead flight director Royce Renfrew pronounced Monday's effort "an excellent EVA day."