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NASA's COLBERT Treadmill

Looming thunderstorms forced NASA to scrub plans to launch the space shuttle Endeavour early Tuesday. The space agency said it would try again early Wednesday at 1:10 a.m.

NASA said there was a 70% chance of favorable conditions for a launch tonight from Florida's Kennedy Space Center. "The primary concern is cumulus clouds and showers within 20 nautical miles of the shuttle landing facility at the time of launch," NASA officials said in a statement.

Teams are set to meet at 3pm to decide on "go- no go" for tanking operations.

The COLBERT treadmill is among the numerous pieces of equipment that will be on board Discovery when it lifts off. The exercise device is named after comedian Stephen Colbert. Discovery also will carry to the ISS the Leonardo supply module, which features refrigerator-size storage racks.

STS-128, as the mission is called, will be commanded by veteran astronaut Rick "C.J." Sturckow. Joining him are six other space goers, including pilot Kevin Ford and mission specialists Patrick Forester, Jose Hernandez, Nicole Stott, and John Olivas. Christer Fuglesang will represent his native Sweden on the mission.

The crew arrived at Kennedy last week for prelaunch preparations.

"It's great to be here for the launch," said Sturckow. "We've been studying and training hard, and we're ready to go accomplish this mission."

NASA officials anticipate a successful mission.

"I can't say enough about the quality of the review we had over the past day and a half," said Bill Gerstenmaier, associate administrator for Space Operations, at a news conference last week. "It was a very effective review; I think we're ready to go fly," he said.

Gerstenmaier added that preparations were a group effort. "It's a real tribute to be here with the team that's done a great job with engineering, the Kennedy team that's gotten us this far in the process," he said.