CAPE CANAVERAL, Fla. - The space shuttle Discovery is in near pristine condition after a flawless Monday landing under a cloud-covered Florida sky.
But while Discovery's return to Earth completed NASA's second shuttle test flight since the 2003 Columbia accident, the mission's end is just the beginning of the agency's long haul to finish the half-built International Space Station (ISS) without compromising astronaut safety.
"Yes, I think the conclusion is that the shuttle is back," NASA's shuttle program chief Wayne Hale said. He added that NASA's Atlantis orbiter is slated to launch one of the most complicated ISS construction missions in just six week's time. "We have the team that is now practiced and battle-hardened ready to go to that with the proper requisite experience to make sure that we will not let any stone go unturned."
Discovery's wheels touched down here at NASA's Kennedy Space Center (KSC) at 9:14 a.m. EDT (1314 GMT) after a 13-day mission to deliver a new crewmember to the ISS, resupply and repair the station, as well as test new concepts for shuttle heat shield safety.
The successful mission - commanded by veteran NASA shuttle flyer Steven Lindsey - opens the gate for the no less than 15 future orbiter missions to build out the ISS by Sept. 30, 2010.
NASA chief Michael Griffin said today that external tank modifications aimed at increasing shuttle flight safety following the Columbia accident, as well as improved heat shield inspection techniques, appear to have been a stunning success. But NASA engineers will have to complete a comprehensive analysis before a final evaluation can be made, he added.
"This is the cleanest orbiter anybody remembers seeing," Griffin said. "What's behind that, we've got to dig in and look. Honestly, when we know, we'll tell you."
A perfect day
While engineers study the results of Discovery's spaceflight, the STS-121 astronauts themselves are meeting with their families after a hectic spaceflight.
Aside from some thick clouds, a finicky air data probe, and a nicked heat-resistant tile near Discovery's nose landing gear door, the spacecraft's Earth return surpassed all expectations, NASA officials said.
"I would give Steve a perfect 10 today," NASA reentry flight director Steve Stitch said of STS-121 commander Steven Lindsey's landing. "He did a superb job putting Discovery right down exactly where we thought with our analysis that he would land. It was a perfect landing."
For NASA launch director Michael Leinbach, Discovery's smooth landing provided a closure of sorts. The touchdown marked the first successful KSC shuttle landing since the loss of Columbia, which was heading towards the Shuttle Landing Facility here when it broke apart over Texas.
"Columbia's landing day was a horrible day," Leinbach said. "Today was a great day."
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