Discovery readies for final countdown

CAPE CANAVERAL, Fla. – After 143 million miles and nearly a year all told in orbit, space shuttle Discovery is poised to blast off today one last time.

It promises to be a sentimental journey for the six astronauts assigned to the mission as well as the supporting cast of thousands who have painstakingly prepped the world’s most traveled rocketship.

Once more, NASA’s fleet leader is paving a new road, one that leads to shuttle retirement and an uncertain future for America’s space program.

When Discovery returns from the International Space Station, it will be the first of the three surviving shuttles to be decommissioned this year and shipped off to a museum. The Smithsonian Institution has first dibs on this one.

But the end of the 30-year shuttle program is still months down the road. For now, NASA prefers to focus on Discovery’s last hurrah, an 11-day mission to deliver a bundle of space station supplies and an experimental humanoid robot that will become the first of its kind in space.

“Discovery is the most flown spacecraft in history,” NASA Administrator Charles Bolden said. “People don’t understand. They say it matter-of-factly. There is no other multi-flown spacecraft than the shuttle.”

It’s been an uncharacteristically bumpy exit for Discovery.

Fuel tank cracks – one of the most challenging problems to strike the shuttles – cropped up during the initial countdown in early November. It took until January for NASA to understand the cracking in the center portion of the tank that holds instruments, and to be assured the repairs would work. Then last month, the lead spacewalker was injured in a bicycle crash and had to be replaced on the crew.

Launch director Mike Leinbach said Discovery has been “a great ship … an amazing machine.”

“This is her 39th mission,” he said Wednesday. “We’d have quite a few left in her had the program been extended, but it wasn’t.”

“Landing day is going to be tough,” he noted, as will landing day be for shuttle Endeavour in the spring and especially for shuttle Atlantis in the summer.

The oldest of the surviving shuttles that first flew in 1984, Discovery carried the Hubble Space Telescope into orbit in 1990, returned Mercury astronaut John Glenn to space at age 77, and got NASA flying again after the Challenger and Columbia shuttle disasters.

“No small feat,” Leinbach observed.

To mark the historic nature of the flight, the six astronauts are taking up a medallion from Britain’s Royal Society that was struck in honor of 18th century British explorer James Cook. His ships included the Discovery, one of the exploring vessels after which the shuttle was named.

Discovery’s planned liftoff at 1:50 p.m. PST– as convenient as it gets – is expected to pack in the crowds. NASA is anticipating 40,000 guests, including 15 members of Congress.