The astronauts on the United States' final space shuttle mission will get one extra day in space.
Using the International Space Station's robot arm, the Atlantis astronauts pulled a bus-size cargo module from the shuttle's payload bay today and attached it to the lab's forward Harmony module to clear the way for a busy week of logistics transfers. The Italian-built Raffaello module is loaded with 9,403 pounds of supplies and equipment, including 2,677 pounds of food, that will help keep the station crew supplied through 2012.
Becausewith a full load of hydrogen and oxygen for its electricity-generating fuel cells, NASA's mission management team today approved a one-day mission extension to give the combined shuttle-station crew an extra docked day to fully unload Raffaello and to repack it with trash and no-longer-needed equipment for return to Earth aboard the shuttle.
"Guys, I wanted to let you know that the [team] has voted and you're now officially a 13-day mission," astronaut Megan McArthur radioed from mission control in Houston.
"Great news," commander Christopher Ferguson replied from the shuttle-station complex. "I'm sure we will fill it up in a very useful fashion for the station folks."
"And that's great news from the station side as well," added station flight engineer Ronald Garan. "These guys have been outstanding house guests. We'd like them to stay as long as they want."
The revised flight plan calls for Atlantis to undock from the space station at 12:56 a.m. ET on Tuesday, July 19, setting up a pre-dawn landing back at the Kennedy Space Center on July 21.
Thanks in part to power conservation measures, Atlantis currently has six hours of margin above the additional day and not counting the two days that are always held in reserve in case of weather-related landing delays.
"That margin is expected to continue to grow, somewhere on the order of one to two hours a day for the remainder of the docked period," said LeRoy Cain, chairman of the mission management team. "This is exactly the right thing to do on this mission, there's a lot of good work we can help the space station program with."
NASA's Damage Assessment Team, meanwhile, is wrapping up its post-launch analysis of Atlantis' heat shield. So far, only one tile ding has been found, Cain said, along with four areas of minor damage to insulating blankets. While the analysis is not yet complete, Atlantis appears to be chalking up the most trouble-free performance of any post-Columbia shuttle mission.
"At this point there are no areas of concern...but per the standard process, the DAT is finishing up with the data review and will report out...tomorrow," the mission management team said in an afternoon update to the crew.
Atlantis docked with the space station yesterday after a flawless two-day rendezvous that began with a launch from the Kennedy Space Center Friday.
Pilot Douglas Hurley and Sandra Magnus, operating the space station's robot arm, began Raffaello's unberthing from Atlantis' payload bay around 5:47 a.m. today. The multipurpose logistics module, or MPLM, was carefully maneuvered to the Earth-facing port of the station's forward Harmony module and locked in place with 16 motor-driven bolts in the port's common berthing mechanism.
The attachment was completed at 6:45 a.m. Five-and-a-half hours later, Raffaello's main hatch was opened and the astronauts, running more than an hour and a half ahead of schedule, floated inside.
Atlantis' mission was added to NASA's shuttle manifest to deliver enough supplies, spare parts, and other gear--in concert with Russian, European, and Japanese cargo ships--to support the station's six-person crew through 2012 even if new commercial cargo carriers designed to take over resupply duties from the shuttle run into problems.
Raffaello is packed with one year's worth of food. "We're taking about 2,000 pounds of science equipment, we're taking hygiene items, we're taking clothing, we're taking thousands of pounds of spare parts for the different systems, life support system, the electrical system, the computer system, and so forth," Magnus said in a NASA interview. "We're trying to supply the station for a whole year, and that hedges our bets against when the commercial follow-on cargo contracts will be up and running."
It will take the combined shuttle-station crew a full week to unload Raffaello and to reload it with 5,660 pounds of trash, packing material, and other equipment that will be sent back to Earth aboard Atlantis.
"It is pretty much an all-hands-on-deck (process)...so it's going to be a very busy time period," said Flight Director Jerry Jason. "That's what this mission's for."
Garan and fellow station flight engineer Michael Fossum plan to stage a six-and-a-half-hour spacewalk tomorrow, the only excursion planned during Atlantis' visit. The primary goals are to move a failed ammonia coolant pump to the shuttle for return to Earth and to install an experimental robotic refueling experiment on the station.
"The most important [objective] is getting the pump module back into the payload bay to return it home so we can do [an] evaluation of why the pump module failed," Jason said. "Getting that back and understanding what the cause of that failure is will help us in the long run."