Discovery's astronauts swarmed through the International Space Station on Saturday, pitching in with repairs and upgrades to life support systems, un-packing supplies from the Permanent Multipurpose Module they delivered and cleaning up the mess created by a visit that was rapidly drawing to a close.
Hatches between Discovery and the International Space Station are to be closed on Sunday, shortly before 4 p.m. EST.
The six shuttle astronauts plan to undock on Monday at 7 a.m. EST, bidding the station's U. S., Russian and Italian crew farewell after a productive nine-day visit.
All 12 members of the two crews made the most of Saturday’s part of a two-day Discovery mission extension.
“You are so far ahead of us, we are playing catch up,” Mission Control told the shuttle astronauts several hours after they went to work on the many tasks.
“Good to hear,” said Discovery skipper Steve Lindsey. “We’re sort of lost in the details.”
Discovery astronaut Steve Bowen, left, and pilot Eric Boe unpack and remove unwanted packing materials from the Permanent Multipurpose Module. Photo Credit/NASA TV
Station commander Scott Kelly led the installation of a new filtration system -- delivered aboard Discovery -- in the Tranquility module's Oxygen Generation Assembly, a life support apparatus that converts recycled urine and atmospheric condensate into oxygen for breathing.
The developmental device, which could play a role in NASA's future deep-space exploration strategies, has been used sporadically for weeks because of a mineral build up and inadequate pH regulation.
Flight controllers took over the overnight OGA re-activation.
Meanwhile, Discovery astronaut Mike Barratt joined European Space Agency astronaut Paulo Nespoli for repairs to one of two Carbon Dioxide Removal Assemblies, which filters the station breathing air of the waste gas. The device, located in the station's U. S. Destiny lab, experienced an elusive short circuit on Feb. 28. Using a multi-meter, the two men traced through the electrical wiring of a heater element to fashion a bypass
A second CDRA in Tranquility, which was also upgraded by the shuttle crew earlier in the week, has been handling most of the CO2 removal in the station's U. S. segment.
In the station's Russian segment, cosmonauts restored operations of the Elektron oxygen generator.
Discovery's astronauts delivered five tons of internal cargo, including new research equipment. Most was delivered inside the new PMM. While Robonaut 2 and a new science rack were offloaded to Destiny, much of the new equipment was unpacked and re-stowed in the new module.
The unwanted packing materials were stripped free and placed as trash in Japan's Kounotori HTV-2 unmanned cargo carrier, Kounotori, which arrived in late January, will be prepared to depart the station on March 28 for a destructive re-entry into the Earth's atmosphere.
Discovery's crew is scheduled to descend to Earth on Wednesday, touching down at NASA's Kennedy Space Center just before noon EST. The 13-day voyage will mark the 39th and final flight for NASA's fleet leading orbiter.