After a busy week at the International Space Station, the six-astronaut crew of NASA's shuttle Endeavour enjoyed some time off Tuesday to rest up at the halfway mark of their long space trek.
The off-duty time gave shuttle commander Mark Kelly, pilot Greg Johnson and mission specialists Greg Chamitoff, Mike Fincke, Andrew Feustel and Roberto Vittori some time to reflect on the milestones of their 16-day mission, which is NASA's final flight of Endeavour before the shuttle is retired this year.
"This is it for Endeavour," Kelly said. "After we land back in Florida, Endeavour will head off to a museum, so it's kind of sad. This mission — we're halfway through it today. Endeavour has to perform really, really well for us. And it has so far. This is an incredible ship."
So far, the shuttle crew has installed a $2 billion astrophysics experiment to the exterior of the station, delivered cargo and supplies, and performed two long and arduous spacewalks. [Photos: Shuttle Endeavour's Final Mission]
The mission's second spacewalk, which was conducted by Feustel and Finke on Sunday, lasted more than eight hours, making it the sixth-longest in history.
On Tuesday, the crew prepared the equipment and procedures for the next spacewalk, which Feustel and Fincke will begin Wednesday at 1:46 a.m. ET. The mission has been running smoothly so far, Fincke said.
"Endeavour is a beautiful bird," Fincke said. "It's taking us through our mission step by step with very few problems, if any. She's doing great and she saved her best for last."
Endeavour's space portrait
The shuttle crew enjoyed some more off-duty time on Monday while three space station residents packed up and returned to Earth.
Russian cosmonaut Dmitry Kondratyev, NASA astronaut Cady Coleman and Italian astronaut Paolo Nespoli landed in Kazakhstan at 10:26 p.m. ET on Monday, after spending more than five months on the International Space Station. [Historic Photo Op: Endeavour and Space Station Together]
It was the first time a Soyuz spacecraft undocked from the space station while one of NASA's space shuttles was also parked at the orbiting outpost. To mark the occasion, and to gather some interesting engineering data, Nespoli photographed the shuttle and the International Space Station from a distance of about 656 feet (200 meters) after the Soyuz initially backed away.
The three returning station residents left behind NASA astronaut Ron Garan and Russian cosmonauts Alexander Samokutyaev and Andrey Borisenko. In a change of command ceremony, outgoing station commander Kondratyev handed the position over to Borisenko, who will now be in command of the new Expedition 28 mission. [Video: Perfect Soyuz Touchdown in Kazakhstan]
Another week ahead
The shuttle astronauts were officially due to begin their day at 8:26 p.m. ET Monday, after the Soyuz undocked, but they were given the option of rising early to witness the undocking. [Space Traffic Jam Means Weird Sleep Patterns for Astronauts]
"What we've communicated to the shuttle crew is that there's no requirement for them to be awake," lead station flight director Derek Hassman explained before the undocking. "There's no expectation or requirement that they be awake, but we did put a message onboard about which windows have good views and cameras. We're leaving it up to their discretion. If it was me, I'd be awake for a couple hours."
NASA expects to release high-resolution images and video of Endeavour and the space station sometime in the next few days.
The space shuttle is slated to return to Earth on June 1 to end its STS-134 mission, which is the 25th and last flight for Endeavour. NASA is retiring all three of its space shuttles after 30 years of service to make way for future deep space exploration of asteroids and, eventually, Mars.
Endeavour, like its sister ships, will eventually be placed on public display at a museum after it flies its final mission.
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