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The first 'last flight'

Matt Stroshane / Getty Images file
The space shuttle Atlantis sits on its Florida launch pad after its April 22 rollout.

NASA today gave the green light for what's likely to be the space shuttle Atlantis' last launch, opening the final chapter in the orbiter fleet's 29-year history. Atlantis' solid-fuel rockets are due to fire up for a final time at 2:20 p.m. ET on May 14. But mission managers say they're not letting that finality sink in fully just yet.

"There's this ability to stay focused and compartmentalize," Bill Gerstenmaier, NASA's associate administrator for space operations, told reporters today at the end of a flight readiness review for Atlantis' 12-day mission to the International Space Station.

"I have not spent a lot of time thinking about 'last this' or 'last that,'" said John Shannon, NASA's space shuttle program manager.

Launch director Mike Leinbach said shuttle workers have been preparing for this STS-132 flight just as they have for the 131 others in the program. "Probably a lot of hugs at the end of the day - but when they're working on the vehicle, it's the standard flow," he said.

Of course, the more than 15,000 workers at Kennedy Space Center in Florida can't help but think about this final scheduled round of three flights for the three remaining orbiters - Atlantis, Discovery, Endeavour. And they can't help but wonder about what will happen when the last shuttle rolls to a stop.

"We've gotten past the denial stage of the change," Leinbach said, "and we're into the exploration and acceptance stage." He said the reflections on Atlantis' flight would be "bittersweet, to be sure."

Last month, President Barack Obama visited the space center, seeking to reassure agency employees as well as contractors that they'd still be playing a vital role in the post-shuttle era. Over the weekend, the White House announced the appointment of a task force to oversee a $40 million program for workforce training and economic development on Florida's Space Coast.

That part of the economic endgame will play out over the months and years to come. But for now, the focus is on the first of the last shuttle flights.

What Atlantis will do
Atlantis' six-man crew, led by commander Ken Ham, will deliver Russia's 17,000-pound, 23-foot-long Rassvet ("Dawn") module to the International Space Station. Rassvet, which is also known as the Mini Research Module 1, has been packed with supplies and equipment for the station. A European robotic arm, radiator and airlock are attached to Rassvet's exterior.

During Atlantis' visit, Rassvet will be hooked up to the station's Zarya control and cargo module during Atlantis' visit, and in 2012 a full-blown Russian orbital laboratory (known as Nauka or "Science") will be added on. Atlantis' trip marks the first time (and almost certainly the last time) that a Russian module has been flown up on a space shuttle. The arrangement follows through on a barter deal for U.S.-Russian space transport.

The shuttle will also carry a pallet containing six fresh batteries for the station's power-generating truss, a new Ku-band communication antenna and a tool platform for the station's Canadian-built Dextre robotic arm. Atlantis' astronauts will install the antenna, add the platform and swap out the batteries during a series of three spacewalks.

Atlantis' history
It's fitting that Atlantis is bringing up the last pressurized module designed from the get-go to be permanently attached to the space station. (In September, Discovery is due to deliver the Italian-built Leonardo logistics module, which has been carried back and forth several times but is now being modified to become a permanent fixture.)

The 25-year-old orbiter carried up the station's U.S-built Destiny laboratory and Quest air lock as well as the European-built Columbus lab. It has also sent up the Magellan probe to Venus, the Galileo probe to Jupiter and the now-defunct Compton Gamma-Ray Observatory, which was once one of NASA's "Great Observatories."

Atlantis will also go down in history as the first shuttle to dock with Russia's Mir space station (in 1995) and the last shuttle to hook up with the Hubble Space Telescope (a year ago).

"She's been around a long time, and a lot of us have known that ship for 25 years," Leinbach said today.

Retired astronaut Jerry Ross, who holds the record for the most shuttle flights (in a tie with Franklin Chang-Diaz), took five of his seven trips to space aboard Atlantis. "Personally, I think it's the best one in the fleet," he half-jokingly told reporters earlier this week.

Is there really a difference in the way Atlantis handles itself in space? The astronauts say the significant differences between flights really have more to do with the payload distribution rather than the characteristics of the particular orbiter. But STS-132 pilot Dominic Antonelli noted that Atlantis lacked something that the other two shuttles have: an extension cord that lets the shuttle tap into the space station's power supply.

"That will limit the duration of our stay," Antonelli said. There's only so much power that will be available to Atlantis while it's docked to the station.

Never say never again
Eventually, all three shuttles are destined to be placed in museums, and the job of transporting payloads to the station will fall to the Russians and commercial launch providers.

But when Atlantis comes back home, it won't be packed up right away. Instead, it will be put through the regular processing routine to serve as a backup rescue vessel, just in case something goes wrong during what is expected to be the final shuttle flight. The current schedule calls for Endeavour to take on that program-ending mission to the International Space Station no earlier than November.

If Endeavour were to suffer so much damage during that last scheduled flight that it couldn't return safely to Earth, Atlantis would be launched with a skeleton crew to bring the marooned astronauts home.

There's yet one more scenario for Atlantis to fly again: If the money is available for yet another flight beyond the three currently planned, Atlantis could conceivably be sent to the space station with a crew of four, to deliver a last load of supplies to the station. That STS-135 flight would have to come sometime next year.

Mission managers say they aren't counting on that STS-135 flight - but they aren't counting it out just yet, either.

The lead shuttle flight director for the upcoming mission, Mike Sarafin, likened this last go-around to the final season of a champion athlete. "We are in the ninth inning," he told reporters. "Atlantis may go into extra innings. We don't know."

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