Viewers of NASA's television channel watched parts of the last few minutes of the flight via a camera mounted behind the shuttle's windshield as commander Steven Lindsey, assisted by pilot Mark Kelly and the onboard set of computers, brought Discovery down.

"It was a really great mission and we enjoyed the entry and the landing," Lindsey said.

The mission, STS-121, included a successful test of shuttle safety improvements, such as thousands of high-resolution video images taken of Discovery from the moment it lifted off until the day before it undocked with the International Space Station, and the shakedown of a 50-foot extension to the orbiter's robotic arm.

After Discovery rolled to a stop and the crew performed their required post-landing chores, they conducted the traditional walk-around inspection.

"I have been on four flights, and this is the cleanest vehicle I've ever seen," Lindsey said. "We had two major objectives and we accomplished both of those, and we're ready to assemble the space station."

At the post-landing news conference, NASA officials seemed pleased with Discovery's performance, saying the flight verified the safety of the biggest aerodynamic change to date to the external fuel tank. Engineers had removed features called protuberance air-load ramps after a one-pound piece of insulating foam had detached from one of the PALs during Discovery's flight in July 2005.

During the visit to the station, mission specialists Mike Fossum and Piers Sellers, with the help of crewmates, completed three spacewalks. The third spacewalk was confirmed after mission managers determined there was enough electrical power to add another day to the flight.

The astronauts tested the shuttle's 50-foot robotic arm boom extension as a work platform. They removed and replaced a cable that provides power, command and data and video connections to the station's mobile transporter rail car. The transporter is used to move a platform containing the station's robotic arm along the truss of the complex.

During the third spacewalk, the astronauts tested techniques for inspecting and repairing the reinforced carbon-carbon segments that protect the shuttle's nose cone and leading edge of the wings.

Discovery also delivered more than 28,000 pounds of equipment and supplies to the station, as well as ESA astronaut Thomas Reiter, who joined Russian Pavel Vinogradov and American Jeff Williams as a member of the station crew - the first time since May 2003 the ISS has hosted three crewmembers.

NASA officials convened the news conference at Kennedy about two hours after the landing.

Responding to a question about NASA's next move regarding shuttle flights, Administrator Michael Griffin said completing the station and the remaining 16 shuttle missions planned comprise the agency's first steps in the new Vision for Space Exploration.

"Our schedule is tight and we don't have any slack - we can't afford to mess up," Griffin acknowledged, but added that the Discovery and station crews and NASA engineers had mounted an unprecedented effort to make the shuttle program as safe as possible.

"Discovery is in outstanding condition," said Mike Leinbach, NASA's launch director. "We had to search for dings to the tiles, and the couple we saw were very, very minor."

Later in the day, Discovery was towed to the Orbiter Processing Facility where it will be readied for its next flight on mission STS-116.

Meanwhile, NASA has begun preparations for the launch of shuttle Atlantis, currently scheduled for late August or early September.

That mission, STS-115, is set to deliver additional truss segments to the station. Atlantis is expected to be moved to the launch pad early next month, and NASA managers plan to meet shortly thereafter to clear the shuttle for its first mission since October 2002.

Related Links
Shuttle at NASA

Memory Foam Mattress Review

SPACE MEDIA NETWORK PROMOTIONS Solar Energy Solutions Tempur-Pedic Mattress Comparison ... Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News