HOUSTON - The astronauts aboard the Discovery orbiter and International Space Station (ISS) are hard at work shifting supplies between the two spacecraft and looking forward to an extra day in space together.

Discovery's STS-114 crew and the station's two Expedition 11 astronauts have a full day of cargo transfer ahead of them, and are commending what has been a successful flight.

"Having the space shuttle back in orbit after a number of years an accomplishment," Discovery's STS-114 commander Eileen Collins told Fox News during a series of interviews from space Sunday. "The second thing is getting the International Space Station resupplied and built, and we're working on that."

Discovery is delivering about 15 tons of material - which includes the weight of a cargo pod - to the ISS, and will return about 13 tons of unneeded equipment and trash back to Earth. The resupply is vital for the space station, which has not seen a shuttle dock at its ports since NASA grounded its shuttle fleet in 2003 after the Columbia disaster.

"We're really looking forward to having these guys stay with us an extra day," said astronaut John Phillips, flight engineer for ISS Expedition 11, told CNN, adding that the shuttle crew will help stow the cargo the they brought to the station. "After we transfer this stuff, it's a little bit of a mess and the more workforce we have here to help put it away the better."

After Discovery's launch, NASA found evidence of unacceptable foam loss from the orbiter's external tank - the same type of debris shedding that critically wounded the Columbia shuttle - and announced it would not launch another shuttle mission until the problem was solved.

Columbia was struck by a 1.67-pound chunk of foam during its 2003 launch that pierced its heat shield and allowed hot gases in during reentry which destroyed the orbiter. During Discovery's July 26 launch Discovery launch, a 0.9-pound piece of foam fell from a protective ramp, but did not strike the orbiter. However, it was a disappointment to NASA after more than two years of work and $1.4 billion to lower risk and increase shuttle flight safety.

The news of the falling foam from Discovery's external tank also disappointed the shuttle's crew, but they agreed that halting future flights until the problem is addressed is a proper course of action.

"We were of a single mind up here that it was necessary to stop flying until we've fixed this," STS-114 mission specialist Andrew Thomas told Fox News. "That's what you do in a situation like this."

Phillips said that that he and Expedition 11 commander Sergei Krikalev were somewhat disappointed when they heard the news of a potential delay in shuttle flights. The ISS crew anticipated the Atlantis orbiter and its STS-121 crew to deliver twice as much science equipment to the space station, as well as a third crewmember - European Space Agency astronaut Thomas Reiter - which would return the station to its full, three-person crew.

"But we're still on track, maybe a little but slower, to resume construction of the station," Phillips told CNN.

To prepare for a potentially extended period between the STS-114 crew's arrival and the next shuttle delivery, ISS and shuttle astronauts will spend their extra day together transferring surplus items, such as like laptop computers, tools, pens, paper, printers and about 20 gallons of water, from Discovery and into the orbital laboratory.

There are also some components inside the Raffaello cargo pod, known as a Multi-Purpose Logistics Module (MPLM) that could be pulled out and pressed into work aboard the space station.

"There are a bunch of lights from the MPLM we could use," Phillips said.

Later today, Thomas and STS-114 mission specialists Stephen Robinson and Soichi Noguchi will go over plans for the second of three spacewalks planned for their mission. That spacewalk, set to begin at 4:14 a.m. EDT (0814 GMT) on Aug. 1, is targeted at replacing an attitude control moment gyroscope that failed on the space station in 2002. Noguchi and Robinson completed their first spacewalk on July 30, testing out a pair of heat shield repair methods for future shuttle flights and performing a series of other ISS maintenance tasks.

Despite their busy schedule, Discovery's crew does anticipate their return to Earth on Aug. 8, when they are scheduled to land at Kennedy Space Center in Cape Canaveral, Florida.

"I'm looking forward to seeing my kids again," Collins told ABC's "Good Morning America". "I miss them a lot."

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