Space Shuttle Discovery Reaches Launch Pad

CAPE CANAVERAL - Shuttle Discovery rolled out to its Kennedy Space Center launch pad Sunday, marking the start of a final push to the planned Oct. 23 launch of an International Space Station assembly mission.

The schedule, however, is extremely tight.

NASA has but one day of leeway, so any significant technical problems could force the agency to readjust the launch schedule.

"It's not a lot of extra time. But you have to take things one step at a time," KSC spokesman Allard Beutel said. "If something else crops up that we have to deal with, then we'll have to deal with it."

NASA is facing a presidential deadline to finish the station and retire its shuttle fleet by Sept. 30, 2010.

So Sunday marked three years and counting for 13 more station assembly flights and a Hubble Space Telescope servicing mission.

NASA had hoped to fly five station assembly missions this year, but a hailstorm in February damaged a shuttle external
tank on the pad, delaying the first 2007 flight to June.

The upcoming Discovery launch will be the third this year, and NASA will have just a seven-day window between Dec. 6 and Dec. 13 to send up a fourth and final 2007 flight.

After that, the sun angle on the station would be such that its solar wings could not generate enough electricity to power both the outpost and a docked shuttle orbiter.

In addition, radiators on the linked spacecraft would not be able to shed enough of the heat generated during docked operations. The next launch opportunity would be about Jan. 2.

Discovery rolled up onto its oceanfront launch pad about six hours after it emerged from the KSC Vehicle Assembly Building.

A tracked crawler-transporter built for the Apollo moon-landing project lifted the shuttle and its mobile launcher platform -- an 11 million-pound load -- and started moving at 6:47 a.m.

Top speed during the 3.5 mile trek: 0.9 mph.

The prime payload for the Discovery mission -- the U.S. Harmony module -- already is at the pad and will be installed in the shuttle's 60-foot-long cargo bay later this week.

Equipped with six hatches, the cylindrical element will serve as a pressurized gateway to still-to-be-launched European and Japanese science laboratories.

Coming up next week: a launch-day dress rehearsal.

A crew led by veteran astronaut Pam Melroy, who will become only the second woman to command a shuttle mission, will board Discovery at the pad and take part in the final hours of a two-day practice countdown.

The astronauts will arrive at KSC next Sunday and also will go through emergency training at the pad.

Shuttle program managers also will meet at KSC next week for a two-day technical review. A first, the review will provide a forum for managers to discuss technical issues before briefing top agency executives during a traditional flight readiness review.

A firm launch date for Discovery will be set at the latter review, scheduled for Oct. 16 at KSC.

Published under license from FLORIDA TODAY. Copyright: 2007 FLORIDA TODAY. No portion of this material may be reproduced in any way without the written consent of FLORIDA TODAY. 

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