Space Shuttle Discovery to Land Today

Space shuttle Discovery and its crew of seven astronauts are poised to come home today after a nearly two-week flight that boosted the International Space Station to full power by adding the outpost?s final pair of solar wings.

Discovery is slated to land at NASA?s Kennedy Space Center in Florida at 1:39 p.m. EDT (1739 GMT) to complete a 13-day flight to the space station. Favorable weather conditions are expected at the shuttle?s Cape Canaveral, Fla., runway were the 100-ton spacecraft is expected to glide in for a landing.

?We?ll keep our fingers crossed,? shuttle commander Lee Archambault told Mission Control Friday.

Archambault and his crew spent eight days docked at the space station, where they performed three spacewalks to install the new expansive solar arrays - the outpost?s fourth and final set - and unfurl them to their 240-foot (72-meter) wingspan.

The shuttle astronauts left the space station on Wednesday to clear the way for a new crew and space tourist Charles Simonyi, who launched toward the orbiting lab a day later aboard a Russian Soyuz spacecraft. The Soyuz is due to dock at the station at 9:14 a.m. EDT (1314 GMT) today.

?This is the calm before the storm,? station commander Michael Fincke told Mission Control Friday. ?The hurricane is coming, the next crew?s on its way.?

Full power to space station

The $298 million solar arrays delivered by Discovery balanced out the space station?s look, giving it eight wings total (two per side), and increased its power grid by 25 percent. They also completed its backbone-like main truss, which is now longer than a football field in length.

With all four arrays in place, the station is designed to generate enough electricity to feed a neighborhood of 42 average size homes, power that is vitally needed if the station is to double its crew size to six later this year and increase its science output. The shuttle crew also helped repair the space station?s water recycling system, which converts astronaut urine and sweat back into pure drinking water to support larger crews.

?Deploying the solar arrays was one of the high points of this flight,? mission specialist John Phillips told students in Hawaii Thursday. ?We?re all really proud to bring that extra power to the station.?

Phillips and his crewmates were speaking with students from Punahou School in Honolulu, President Barack Obama's high school alma mater, just days after receiving a phone call from the president himself praising their mission.

Set to return to Earth aboard Discovery with Archambault and Phillips are shuttle pilot Dominic ?Tony? Antonelli and mission specialists Joseph Acaba, Steven Swanson, Richard Arnold II and Sandra Magnus. Acaba and Arnold are former schoolteachers and making their first spaceflight along with Antonelli.

Magnus is retuning home after spending 134 days in space. She arrived at the outpost last November and was replaced by Japanese astronaut Koichi Wakata - Japan?s first long-term station resident - who launched with Discovery?s crew on March 15.

?It was a lot of fun on the space station,? Magnus told Mission Control this week. ?A truly unique adventure.?

Magnus told reporters she will miss the views from space - especially the colors of the waters around the Caribbean - but is looking forward to being outside for the first time in months, and perhaps a chocolate milkshake, some sushi and a cheesy pizza.

About five months? worth of experiment samples, including blood, biological samples in a freezer and cold storage bags, as well as four of five liters of recycled water from the station?s urine recycler, are also packed aboard Discovery.

Landing options

Before flight, Archambault told reporters he was looking forward to guide Discovery home.

?I?m looking forward to flying this thing for real,? he told reporters before flight. ?You don?t have any engines. It is a 200,000-pound glider and you?ve got one chance to do it right.?

The shuttle actually has two chances to land today at the Kennedy Space Center. If weather does not cooperate for the first window, the shuttle can skip that one and try again at 3:13 p.m. EDT (1913 GMT).

Shuttle entry flight director Richard Jones told reporters Friday that he intends to only aim for a Florida landing today and, if needed, on Sunday because of favorable weather. NASA typically prefers to land shuttles at the Florida spaceport to avoid the extra time and cost of ferrying orbiters from a backup runway in California. Discovery has enough supplies to stay in space until Tuesday, he added.

Jones said shuttle engineers will be watching Discovery?s landing extra closely today because of a special heat-resistant tile attached to its underbelly near the rear of its left wing. The tile has a slight ?speed bump? to disturb the hypersonic flow of 3,000 degree Fahrenheit (1,649-Celsius) gases around Discovery while it flies at Mach 15 during landing. Nearby sensors will measure any temperature increases from the bump.

The tile is part of an experiment to that may aid heat shield design for NASA?s new Orion spacecraft and poses no risk to Discovery and its crew, the agency has said. A Navy plane will fly beneath Discovery during its approach to observe it with a long-range infrared camera.

Jones said everything was in place for both the experiment and the shuttle?s landing. ?

?The vehicle is healthy and the crew is ready to come home,? Jones said.

SPACE.com is providing continuous coverage of Discovery?s STS-119 mission with reporter Clara Moskowitz and senior editor Tariq Malik in New York. Click here for mission updates and SPACE.com's live NASA TV video feed. LIVE landing coverage begins at 10:00 a.m. EDT (1400 GMT).

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