Atlantis counting down to Friday launch

Clocks began ticking down from T minus 43 hours at 4 p.m., a half-hour after teams were called to their Launch Control Center stations. The countdown includes seven planned holds ranging from 10 minutes to nearly 14 hours.

Crews are configuring shuttle avionics systems, and Atlantis' payload bay doors are closed around a Russian module and a palette of parts being hauled to the International Space Station.

Atlantis' crew of six had a chance to inspect the payload this morning before the doors were closed.

Mission commander Ken Ham and pilot Tony Antonelli also practiced landings in a Shuttle Training Aircraft. All the crew members had their orange launch-and-entry suits checked for a snug fit.

The crew -- which also includes mission specialists Steve Bowen, Mike Good, Garrett Reisman and Piers Sellers -- also reviewed their plans for launch day, which call for them to board Atlantis at 11 a.m. Friday.

Early Wednesday, crews are scheduled to begin preparations for the loading of fuel cell reactants around 1 p.m., a hazardous operation that will clear launch pad 39A for the afternoon.

The Mission Management Team is scheduled to meet at 9 a.m. to review systems' readiness and give a "go" or "no-go" to proceed toward liftoff. A pre-launch news conference is scheduled for no earlier than 11 a.m. -- watch it live here by clicking the NASA TV box at right.

If everything goes according to schedule, the pad's Rotating Service Structure will swing open to its launch position at 5:30 p.m. Thursday. Fueling of the shuttle would start just before 5 a.m. Friday.

The weather forecast for Friday, and throughout the weekend, is 70 percent "go."

IMAGE: In Firing Room 4 of the Launch Control Center at Kennedy Space Center on May 5, Shuttle Launch Director Mike Leinbach examines a collage created in tribute to space shuttle Atlantis. The three dimensional collection of objects and images was created by Atlantis' processing team. It is being hung on the wall of the firing room in time for the launch of Atlantis' last scheduled mission, STS-132. Collages centering around the processing milestones and missions of the other four shuttles also are in development and are expected to be ready for display in the firing room this summer. Photo credit: NASA/Jim Grossmann.The countdown to Atlantis' 2:20 p.m. Friday launch is officially under way at Kennedy Space Center.