(AP) -- NASA's orbiting astronauts detached a huge storage bin full of trash from the International Space Station on Monday and loaded it aboard Atlantis for the last shuttle ride back to Earth.
The astronauts used a hefty robotic arm to move the bus-size canister, stuffed with nearly 3 tons of packing foam and other space station refuse.
It was the last job shared by the shuttle and station crews, numbering 10 astronauts altogether. Coming up fast was the closing of the hatches between the two spacecraft in preparation for Tuesday's undocking.
The astronauts steeled themselves for what was expected to be a heartfelt goodbye, given that a space shuttle will never fly again.
Emotions already were welling up, down at Mission Control.
Lead flight director Kwatsi Alibaruho has one more shift remaining before signing off forever from shuttle Mission Control in Houston. He said he and his team vacillate "between intense pride at how well this mission has gone, and sometimes being somewhat freaked out, for lack of a more technical term."
Whenever he pauses to think about the finality of it all, "I get kind of freaked out and have this sinking feeling in my stomach that lasts about five or 10 seconds, and then I go back to doing an impersonation of a steely-eyed missile man." he told reporters Monday.
Atlantis will pull away from the space station early Tuesday and aim for a pre-dawn touchdown Thursday. Then it will be retired.
As a final salute, the space station will rotate 90 degrees to provide a new angle for pictures.
It will be some time before there are so many people aboard the space station again. The Russian Soyuz capsules - the only way to get astronauts to the space station for at least the next few years - carry no more than three.
Most of the new commercial spacecraft under development also would seat three, although a few may hold four or more. These are still three to five years away from flying.
The 21-foot-long storage canister - named Raffaello, given its Italian roots - was launched aboard Atlantis back on July 8. It carried up nearly 5 tons of food, clothes and other household goods - enough to keep the space station going for another year.
NASA wanted to stockpile the orbiting lab in case private companies get delayed in launching their own cargo ships. The first such supply run is expected by year's end.
The retirement of NASA's three remaining shuttles has been in the works since 2004, barely a year after the Columbia disaster. Then, President George W. Bush announced a new exploration vision aimed at returning astronauts to the moon. President Barack Obama nixed the moon in favor of an asteroid and Mars. The target launch dates: 2025 for an asteroid and the mid-2030s for the red planet.
Atlantis will remain at Kennedy Space Center for retirement, going on public display. Discovery and Endeavour will be transported to museums in suburban Washington and Los Angeles, respectively.
While many will descend on Kennedy for Thursday's 5:57 a.m. touchdown - and all the shuttle tributes - Alibaruho will remain in Houston. He debated whether to be attend the final landing by a space shuttle, but decided to observe it from Mission Control - "entirely appropriate because that's, of course, how I've lived."
"It's home, so that's where I'll be."
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More information: NASA: http://www.nasa.gov/shuttle