February 20, 2008

Successful Landing for Space Shuttle Atlantis

CAPE CANAVERAL, Fla. -- These are busy times in space. The space shuttle Atlantis glided to a safe landing at the Kennedy Space Center at 9:07a.m. Wednesday, giving the Navy the green light to shoot down a runaway spy satellite before it falls on its own, possibly on a populated area.

Moments after the landing, the Pentagon announced that the window of opportunity now was open for its attempt to hit the low orbiting satellite with a missile, though poor weather at sea might delay the effort until Thursday.

"Really, there wasn't a lot of concern," about debris hitting the shuttle had the attempted shoot down happened while the shuttle was in orbit, Bill Gerstenmaier, associate NASA administrator for space operations, said after Atlantis returned. "It just seemed to be prudent if we could land the shuttle, to have the shuttle down. Then there is no concern at all."

Asked whether debris from the planned shoot down might be a problem for the launch of the space shuttle Endeavour on March 11, Gerstenmaier said: "We don't think it will be a problem, but we will continue to analyze it and make sure it is not a problem or not a concern to us." Atlantis approached the space center on a path that took it over Fort Myers in Southwest Florida.

Preceded by the famed sound of twin sonic booms, the gleaming shuttle sloped through chilly blue skies punctuated with white, puffy clouds, landing from north to south.

As Atlantis rolled to a stop, bringing seven crew members home from their construction mission to the International Space Station, workers at a launch pad just a few miles away continued their own mission -- preparing shuttle Endeavour for the March 11 launch.

That mission is one of about a dozen left to continue building the space station. The Endeavour shuttle crew will transport a Japanese logistics module to the station.

If Endeavour is launched March 11, that will mark one of the briefest periods between shuttle launches in the last decade.

Space officials are excited about getting so many launches off the ground this year.

"I don't consider this a hectic pace or any kind of pressure on us," Gerstenmaier said.

"It feels really good to be having missions back-to-back like this again. It almost feels like the mid-'90s again," said Mike Leinbach, shuttle launch director.

The Atlantis crew blasted off Feb. 7 carrying the European Space Agency's Columbus Laboratory, a 23-foot long module for science research.

Besides commander Steve Frick and pilot Alan Poindexter, the Atlantis crew included American mission specialists Stanley Love, Leland Melvin and Rex Walheim. The crew also included German astronaut Hans Schlegel and French astronaut Leopold Eyharts.

Eyharts stayed behind to serve a stint on the space station and Atlantis brought back U.S. astronaut Daniel Tani, whose mother was killed in a Dec. 19 car accident while he was serving an extended tour aboard the orbiting laboratory.

As for Wednesday evening's activities overhead:

Last week, President Bush approved a military plan to fire a specially modified missile from a Navy ship in the Pacific to knock down the spy satellite, which was launched in December 2006.

The satellite failed shortly after arriving in space. The satellite's fuel tank is filled with 1,000 pounds of hydrazine, a chemical that is potentially toxic.

Though much of the school bus-size satellite would burn up when it reenters the Earth's atmosphere, a big chunk, including the hydrazine fuel tank, would likely make it to the Earth's surface if left to fall on its own, probably early in March.

STS-122 Landing Blog

9:08 a.m. - Wheels stop and the STS-122 mission has ended. Space shuttle Atlantis is sitting on the north end of the Shuttle Landing Facility and a convoy of support vehicles is on its way to the orbiter.

9:07 a.m. - Main gear touchdown!

9:06 a.m. - Atlantis is on final approach to runway 15 from the northeast and will flare just before deploying its landing gear and touching down on the runway.

9:05 a.m. - The space shuttle has been spotted in the skies over Kennedy. A pair of sonic booms will echo over the space center soon and Atlantis will make its final approach to the runway.

9 a.m. - Atlantis is being watched by long-range tracking cameras as it soars over Florida.

8:57 a.m. - Atlantis is over Florida. Less than 200 miles to go for Atlantis to reach the spaceport at Kennedy Space Center.

8:55 a.m. - Atlantis is over Central America and will skirt the coast of the Yucatan Peninsula before heading over the Gulf of Mexico on a heading that will bring it over the west coast of Florida in a few minutes. Commander Steve Frick will steer the shuttle onto an approach to land from the northeast on runway 15 at Kennedy Space Center.

8:50 a.m. - Atlantis and its crew of seven are surrounded by an envelope of supercharged plasma as they ride through thickening layers of the atmosphere. The heat shield is doing its job by insulating the shuttle from the heat and friction of the entry.

The sensation of gravity is also returning to the crew. For NASA astronaut and former International Space Station resident Dan Tani, this is the first weight he has felt in 120 days. He moved onto the station four months ago during the STS-120 mission.

8:40 a.m. "“ Atlantis is in entry interface, which means it is starting to encounter the fringes of the atmosphere. The friction with the thickening air slows Atlantis down before it starts its supersonic glide through the atmosphere on the way to Kennedy Space Center. Atlantis' altitude is about 400,000 feet over the Pacific Ocean. Landing remains scheduled for 9:07 a.m. EST.

The crew has activated the aerodynamic surfaces of Atlantis' wings and body flap and they are reported working and in good shape.

8:15 a.m. - Atlantis remains on schedule to land at NASA's Kennedy Space Center at 9:07 a.m. EST. Atlantis will reach the upper layers of the atmosphere in less than 20 minutes. The flight path will take the shuttle over parts of Central America and the Caribbean Sea before crossing over the west coast of Florida and gliding over Centeral Florida. Atlantis will land from the northeast at the Shuttle Landing Facility, using runway 15.

8:02 a.m. - The de-orbit burn went as planned and space shuttle Atlantis has slowed so it will begin picking up traces of the atmosphere shortly. Commander Steve Frick will align Atlantis so its black-tiled belly will take the brunt of the entry forces.

7:59 a.m. - Mission Control reports that the deorbit burn began on schedule and the engines are firing to slow Atlantis from its orbital speed of about 17,500 mph. Atlantis was near the Philippines when the burn began.

7:48 a.m. - Commander Steve Frick is maneuvering space shuttle Atlantis so he can fire the two orbital maneuvering system engines to slow the spacecraft down in order to enter the atmosphere on its way to Kennedy Space Center. Atlantis will be turned so it is flying backwards and upside down in relation to the Earth. The engines will fire for two minutes and 40 seconds.

The morning at Kennedy Space Center brings a modest layer of thin clouds and very light winds. Atlantis is to make its final approach from the northeast.

The deorbit burn is set to begin at 7:59 a.m.

7:35 a.m. - The seven astronauts onboard Atlantis are seated for the return to Earth. Commander Steve Frick and Pilot Alan Poindexter are in the front two seats on the flight deck where they are surrounded by switches and readouts crucial for flying. Each also has a joystick they will use to fly Atlantis during the entry and glide to Earth.

Mission Specialists Leland Melvin and Rex Walheim are sitting behind the commander and pilot and both act as flight engineers. That means they help the two during the series of maneuvers and approach. They also call out key milestones during the process.

Mission Specialists Stanley Love, Dan Tani and European Space Agency astronaut Hans Schlegel are seated on the middeck, or lower level of the crew compartment. Because Tani is returning after four months in orbit, special considerations are made to help him adjust to the onset of gravity. Typically, space station residents lie down with their feet up during the return to Earth.

7:32 a.m. - Mission Control has given Atlantis and its crew of seven the "go" for de-orbit burn. That will put Atlantis on course to land at Kennedy at 9:07 a.m. EST.

7:30 a.m. - Good morning and welcome to nasa.gov's continuous coverage of the return of space shuttle Atlantis to NASA's Kennedy Space Center. Landing is scheduled for 9:07 a.m. EST. The weather is good this morning and forecasters have given the conditions a "go" to land on the first opportunity.

There are four landing opportunities for Atlantis today, two at Kennedy in Florida and two at NASA's Dryden Flight Research Center in California.

The seven astronauts aboard Atlantis have closed the payload bay doors in preparation for coming home this morning and are waiting for Mission Control to give a "go" for the de-orbit burn, which will slow the shuttle down so it can enter the atmosphere and glide to the runway at Kennedy.

Mission Control is expected to radio a "go-no go" decision in about 10 minutes.


On the Net: