CAPECANAVERAL, Fla. - The clock is ticking for NASA's shuttleDiscovery as launch controllers began counting down towards the spacecraft'splanned Dec. 7 launch late Monday.
NASAcontrollers reported to their consoles in Firing Room 4 at the Launch Control Center here at the Kennedy Space Center (KSC) at 10:30 p.m. EST(0330 Dec. 5 GMT) today and countdown clock began ticking towards liftoff 30minutes later.
"Five,four, three, two, one, and the clock is rolling," said NASA commentatorBruce Buckingham. "Countdown has begun for NASA's first night time launchin four years."
Discoveryis slated to blast off on Thursday, Dec. 7 at 9:35:47 p.m. EST (0235:47 Dec. 8GMT). The T-43 hour countdown includes 27 hours, 36 minutes of built-in holdtime.
Current weatherforecasts predict a 80 percent chance that launch will proceed as scheduled,although there are some concerns of low clouds and isolated showers.
Thefive-man, two-woman STS-116crew flewinto KSC from Houston yesterday afternoon. In these final days leading upto the launch, they will be performing final inspection of the hardware andtools they will use during their 12-day construction mission on the International SpaceStation (ISS).
Discoverycommander MarkPolansky and pilot WilliamOefelein are also practicing shuttle landing, said NASA spokesperson KylieClem.
"Therest of the time is studying the mission and free time," Clem told SPACE.com.
Riding withPolansky and Oefelein will be mission specialists NicholasPatrick, RobertCurbeam, JoanHigginbotham, SunitaWilliams and ChristerFuglesang, a European Space Agency (ESA) astronaut who is also the firstSwede to fly in space.
The STS-116crew is tasked with rewiringthe electrical grid of the ISS and delivering a new $11million portside piece of the orbital laboratory. Williams will alsorelieve ESA astronaut ThomasReiter who has been aboard the station since July.
ISS flightcontrollers also successfully performed a 23-minuterocket burn to boost the orbital laboratory to a higher orbit Mondayafternoon in preparation for docking with the shuttle on Dec. 9. Attempts to doso last week were cut short due to an unexpected shift in the station'sorientation caused by the installation of new ISS components in September.
A failureto raise the station's orbit would have cut into the shuttle's launch window,which currently runs from Dec. 7 to 17 and possibly later if shuttle missionmanagers approve Discovery for flight over the end-of-yearrollover.
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