KENNEDY SPACE CENTER, Fla. - Thunderstorms threatened last-minute preparations for Friday's final shuttle launch, and NASA said there was only a 30 percent chance that the shuttle Atlantis would blast off as scheduled.
Pouring rain dampened the spirits of hundreds of thousands of people gathered in central Florida to watch the last shuttle go into space. Local media reports estimated that as many as 1 million people would try to see Friday's launch, scheduled for 11:30 a.m.
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Lightning struck near the launchpad several times, delaying the retraction of the rotating scaffolding that surrounds the shuttle and its launch rockets on the launchpad, NASA said. Thick clouds darkened the sky.
"Weather is not looking good for launch," shuttle weather officer Kathy Winters told reporters. There is only a 10-minute window for the launch Friday.
If the launch is scrubbed, it could be rescheduled for 11:04 a.m. Saturday or 10:38 a.m. Sunday. After that, the next available date is July 15.
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Hotels in the area were full, and some sightseers were camping at prime viewing spots for the launch, which can usually been seen as far as 60 miles away along the coast.