NASA Looking To Launch Discovery As Early As Feb. 24

NASA is evaluating late February launch dates for shuttle Discovery, and its stalled mission to the International Space Station could set sail as early as Feb. 24, officials said today.

A robotic European space freighter would need to dock at the international outpost a few days earlier than planned to clear the way for a Feb. 24 shuttle launch. Liftoff time that day would be targeted for 4:50 p.m. EST.

Discovery and six astronauts had been slated to blast off in November but inspectors discovered small cracks in support beams that link the upper and lower sections of the shuttle's 15-story external tank.

Technicians now are shoring up 32 of 108 so-called "stringers," which each are 21 feet long.

NASA had been targeting a launch window between Feb. 3 and Feb. 10, but managers decided Thursday that all repair work, analyses and testing could not be completed in time to make a launch attempt during that period.

The next available opportunity at this point is a window that would stretch from Feb. 27 to March 6. Targeted liftoff times during that period would be:

++ 3:36 p.m. Feb. 27.

++3:13 p.m. Feb. 28.

++ 2:48 p.m. March 1.

++ 2:25 p.m. March 2.

++ 1:59 p.m. March 3.

++ 1:37 p.m. March 4.

++ 1:11 p.m. March 5.

++ 12:49 p.m. March 6.

The opening of that window is based on a planned Feb. 26 docking of the European Space Agency's second Automated Transfer Vehicle, a robotic cargo carrier dubbed "Johannes Kepler." The ATV is to be launched Feb. 15 aboard an Ariane V rocket at Guiana Space Center in Kourou, French Guiana, South America.

A series of maneuvers are scheduled during the spacecraft's rendezvous with the station, including a test of a collision avoidance maneuver that would be commanded by ground controllers, astronauts on the outpost, or the spacecraft itself in a docking emergency.

Mission managers are trying to determine whether the timeline for the on-orbit tests can be compressed. A docking on Feb. 23 would clear the way for shuttle Discovery to launch on Feb. 24.

Senior NASA managers, meanwhile, will meet early next week to decide whether additional support beam modifications are required to ensure the shuttle's external tank is safe to fly.

Potential launch dates will be discussed at a program review board meeting on Thursday.

ABOUT THE IMAGES: Click to enlarge the NASA images of shuttle Discovery in the Kennedy Space Center Vehicle Assembly Building. You can also click on the enlarged images to get a bigger, more detailed view. The top photo shows the 15-story tank in High Bay 1 of the assembly building. The second shows a technician shoring up support beams with small brackets. Photo credits: NASA/Frank Michaux (top) and NASA/Jack Pfaller.