Thisstory was updated at 2:00 p.m. EDT.
CAPECANAVERAL, Fla. - NASA is watching the weather for Tuesday?s planned launch ofthe space shuttle Discovery.
Rainshowers and thick clouds are the chief hurdles facing Discovery?supcoming space shot, with current forecasts predicting a 60 percent chanceof favorable launch conditions. The clock began counting down to the shuttle?s plannedlaunch at 2:00 p.m. EDT (1800 GMT) today.
?We haveseveral concerns for launch day,? said NASA shuttle weather officer KathyWinters in a mission update here at the Kennedy Space Center (KSC).
Winterssaid a frontal boundary of weather will bring rain showers over Discovery?slaunch site today and throughout early next week, but should steer clear byTuesday. Only remaining rain showers and thick clouds may post a threat toDiscovery?s launch, she added.
Commandedby veteranshuttle astronaut Pamela Melroy, Discovery?s seven-astronaut crew is set tolaunch on Oct. 23 at 11:38 a.m. EDT (1538 GMT) to begin a 14-day constructionflight to the International Space Station (ISS). Discovery will deliver thevital connecting node Harmony and ferry a new crewmember to the station as partof NASA?sSTS-120 mission.
?We aretracking no issues in our preparations at this point," NASA test directorCharlie Blackwell-Thompson told reporters.
Shuttleworkers are expected to begin loading the super-cold liquid hydrogen and liquidoxygen used to power Discovery?s three fuel cells at 10:00 a.m. EDT (1400 GMT)on Sunday, but could delay the operation should poor weather intervene, saidBlackwell-Thompson, adding that there is plenty of time to make up any delayedwork in time for Tuesday?s launch.
NASA hasuntil Dec. 11 to launch Discovery?s STS-120 mission, but plans to make up tofour attempts within five days, beginning with the Oct. 23 opportunity. Shouldweather prevent Tuesday?s planned launch, the weather outlook remains the same- 60 percent chance of favorable launch conditions - for Wednesday andThursday, Winters said.
Meanwhile,the 31,400-pound Harmony connecting node and a trio of spare space stationparts are stowed inside Discovery payload bay and ready for their trip to theISS. With its multiple attachment points, Harmony will serve as a hubfor future international laboratories to be launched to the space station.The first new laboratory - the European Space Agency?s Columbus module - isslated to launch aboard the shuttle Atlantis on Dec. 6.
?We areready to go," said NASA?s STS-120 payload manager Glen Chin.
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