Weather Looks Good for Wednesday Space Shuttle Launch

The crew of mission STS-115 stop to talk to the media after arriving at NASA Kennedy Space Center's Shuttle Landing Facility to prepare for a second launch attempt on Sept. 6 to the International Space Station. Seen here, left to right, are mission specialists Steven MacLean and Joseph Tanner, commander Brent Jett, pilot Christopher Ferguson, and mission specialists Heidemarie Stefanyshyn-Piper and Daniel Burbank. CREDIT: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. - The weather odds are in NASA's favor for its planned Wednesday launch of the space shuttle Atlantis.

Atlantis and its six-astronaut crew have an 80 percent chance of clear skies at 12:29 p.m. EDT (1629 GMT) Wednesday, when they expect to rocket spaceward towards the International Space Station (ISS), shuttle weather officials said here at NASA's Kennedy Space Center (KSC). Subsequent launch opportunities on Thursday and Friday offer a 70 percent chance of favorable conditions, they added.

"Overall, the weather looks good for launch day and we're looking forward to it," shuttle weather officer Kathy Winters said Monday in a status briefing.

Commanded by veteran shuttle flyer Brent Jett, Atlantis' STS-115 crew will deliver a $371.8 million set of new solar arrays and massive trusses to the ISS in what will mark NASA's first space station construction mission since late 2002.

The shuttle mission is NASA's third since the 2003 Columbia tragedy and has been delayed several times from its Aug. 27 target by poor weather, first due to a launch pad lightning strike and related spacecraft checks and then by Tropical Storm Ernesto. Atlantis now has several final opportunities to fly during a three-day window from Sept. 6-8 to avoid conflicts with an upcoming Russian Soyuz launch on Sept. 18.

"Atlantis and her crew have been waiting for years to complete this mission, and thanks to Ernesto they've had to wait a week longer or so," said Jeff Spaulding, NASA test director, during the briefing, adding that aside from some cosmetic damage to Atlantis' foam-covered external tank the spacecraft weather Ernesto well. "That wait's nearly over."

Spaulding said analysis is still underway to determine whether shuttle officials will actually target three consecutive launch attempts should it become necessary.

Meanwhile, pad crews have completed loading the cryogenic liquid oxygen and liquid hydrogen used to power Atlantis' fuel cells aboard the orbiter. Engine checks are scheduled for later this evening.

Atlantis' 17.5-ton payload - the Port 3/Port4 (P3/P4) truss segment and its solar arrays - remain in fine condition tucked in the shuttle's cargo bay. The payload's batteries will not have to be recharged since their Aug. 24 boost, shuttle officials said, though experiment packages containing yeast and microbes will be loaded into Atlantis' middeck lockers Tuesday afternoon.

"We're tracking no issues at this time and we're right on track with our timelines," Spaulding said.

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• Gallery: Prepping Atlantis
• Complete Space Shuttle Mission Coverage
• NASA's STS-115: Shuttle Atlantis to Jump Start ISS Construction
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