The countdown to Endeavour's 5:40 a.m. Wednesday launch from Kennedy Space Center has officially picked up again, after a nearly four-day pause. At 1:15 p.m., clocks at KSC started ticking down from T minus 11 hours (though it's hard to see in the cell phone photo at left). This link takes you to a replica clock showing the official time.
The countdown includes preset holds along the way to give managers time to catch up on work or troubleshoot problems.
A short time ago, workers at Kennedy Space Center rolled back the Rotating Service Structure at launch pad 39A to its launch position, revealing Endeavour.
By 3 p.m., workers expect to finish final tests and closeouts of a repaired launch pad vent line that was the source of Saturday's scrubbed launch attempt during fueling operations.
The line routes excess gaseous hydrogen from Endeavour's external tank to a flare stack where it is burned off safely. Technicians replaced a quick disconnect valve that connects the line to the external tank, and seals on either side of it.
The same procedure solved a similar problem during Discovery's March launch.
The test of its success this time will come with the loading of a half-million gallons of super-cold liquid hydrogen and liquid oxygen into the 15-story external tank starting at 8:15 p.m.
The forecast for fueling and launch is 80-percent "go."
As posted earlier: You can watch live NASA TV coverage of the tanking operation tonight right here in The Flame Trench. Simply click the NASA TV box on the righthand side of this page to launch our NASA TV viewer, and be sure to refresh this page for periodic updates.
Live NASA TV coverage of the final countdown and launch will begin at 12:30 a.m., and then join us out on our home page -- www.floridatoday.com -- for live countdown status reports and interviews beginning at 5 a.m.
At 5 a.m., we'll chat with Joe Oliva, a senior program manager at ATK, about plans for the first test-flight of the new Ares I rocket, which is being developed to send American astronauts back to the moon by 2020.
At 6 a.m., Matthew Fields of The Boeing Co., will be live with us to talk about the Endeavour crew's plans to perform an unprecedented change-out of high-voltage batteries that have been powering station systems for almost 10 years.
Six of the $3.6 million batteries, each of which weigh 375 pounds and are the size of a small dining room buffet, will be swapped out during two of five spacewalks the astronauts aim to accomplish during what promises to be the longest station assembly mission to date.
At 6:30 a.m., Andrea Farmer of the Kennedy Space Center Visitor Complex will tell us how we all can get an up-close view of this week's planned launch of an Atlas V rocket from Launch Complex 41 at Cape Canaveral Air Force Station.
The 20-story Atlas V is slated to blast off with NASA's Lunar Reconnaissance Orbiter and a piggyback payload -- as early as 5:12 p.m. Thursday.
An Atlas V launch on Thursday is probably only possible if Endeavour's launch scrubs before midnight tonight. Should it slip until Friday, three one-second launch opportunities would come at 6:41 p.m., 6:51 p.m. and 7:01 p.m.
A shuttle slip Wednesday would push the Endeavour mission back to no earlier than July 11. The sun angle on the station between June 21 and July 10 would be such that the outpost would not be able to generate enough power, or dispel enough heat, to support a docked shuttle mission.
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