Discovery Launch Set For 8:47 PM EST

After having its hopes for a Thursday night launch dashed by a stubborn cold-front, NASA will try again Saturday to send the space shuttle Discovery on its way to the International Space Station. Launch time is set for December 9, at 8:47 pm EST.

If Thursday night was a heartbreaker for ground controllers at NASA -- the launch was scrubbed at the exact 9:35 pm EST scheduled launch time, after a countdown hold for weather lapsed past the launch window -- it came as a notable letdown to the the crew of six astronauts onboard Discovery, who had been strapped in to the orbiter for several hours.

"With a little bit of luck hopefully we'll get off and get a great start to the holiday season for everybody," Commander Mark Polansky said, when informed the launch decision was going to go down to the last moment.

When told the mission was officially postponed, Polansky remained upbeat. "We understand. We'll be ready to support the next time we get a chance," he told mission control in Houston.

Clouds also blanketed emergency landing sites in Zaragoza and Moron, Spain, as well as near Istres, France. Had a post-launch emergency caused problems that forced the shuttle to abort its ascent into space, those clouds could have caused significant problems.

In such scenarios, the shuttle's pilot is required to fly a largely visual landing approach... and in the unpowered orbiter, go-arounds aren't an option.

"The weather is the weather," NASA Administrator Michael Griffin told the Houston Chronicle. "The shuttle is a difficult, fragile machine. It has enormous capabilities, but it's fragile."

"We know it can be operated safely with the utmost of care," he added. "The guys are providing that."

Unfortunately for NASA, conditions for Saturday don't look much better for launch... as clouds and rain are once again forecast. The weather really doesn't clear up until Tuesday.

NASA has until December 17 to launch the mission, in order to have the orbiter back on earth in time for Christmas. As a worst-case scenario, NASA could launch as late as December 26, which may require the mission to be cut short in order to have the orbiter back on Earth before the New Year.

As Aero-News reported, the computers onboard the Discovery aren't calibrated to handle the switchover to the New Year while in orbit. The glitch could lead to a loss of calibration between the shuttle, and computers on the ground. NASA has a fix in the works, but engineers are reluctant to implement it as it could lead to other problems.

FMI: www.nasa.gov