At NASA's Kennedy Space Center in Florida, the six STS-129 crew members will climb aboard space shuttle Atlantis on Launch Pad 39A. They will go through a complete launch countdown simulation right up to the point of liftoff.
This is part of the Terminal Countdown Demonstration Test, or TCDT, typically conducted during a 3-day period about two weeks prior to launch. But this practice session was postponed because of a scheduling conflict with the launch of NASA's Ares I-X test rocket.
After the launch simulation and emergency pad escape training, the astronauts will inspect the cargo that they'll fly to the International Space Station before returning to NASA's Johnson Space Center in Houston this afternoon.
Atlantis is scheduled to launch on its 11-day supply mission to the space station on Nov. 16 at 2:28 p.m. EST.