Space Shuttle Discovery's Final Launch Date Still Unclear

NASA has yet to set a firm launch date for the final flight of space shuttle Discovery, after an hours-long meeting today to review technical issues that have grounded the orbiter for over a month.

Top shuttle program mangers met today (Dec. 2) to evaluate the repairs that were made to Discovery's massive external fuel tank.

Engineering teams at NASA's Kennedy Space Center in Cape Canaveral, Fla. have been compiling data in order to determine the root cause of cracks that were found on the metal ribs of the shuttle's external tank. From today's discussion, officials held off on assigning a firm launch date for Discovery's final mission to the International Space Station.

"They came out of the meeting saying, 'we need to gather more information and we need more analysis,'" NASA spokesman Allard Beutel told SPACE.com. "They're still working on the initial cause. This was a status update meeting rather than decision-making meeting."

NASA had been aiming for a Dec. 17 launch for Discovery, but Beutel said shuttle mission managers are making decisions driven by data rather than a timeline.

"We really don't have a new target launch yet ? we have not had one since Nov. 5," Beutel said. "Here at Kennedy, we're doing things to maintain Discovery's launch readiness to support a Dec. 17 liftoff, but that's really just the first available launch opportunity."

NASA has a short window in which to try and launch Discovery this month.

The mid-December launch window for Discovery opens on Dec. 17 and runs through Dec. 20. With some coordination, shuttle managers may be able to extend the December launch window, Beutel said, but would want to avoid having the orbiter in flight over the transition into the new year. [INFOGRAPHIC: NASA's Space Shuttle from Top to Bottom]

At the end of this month, the computers onboard the shuttle need to be reconfigured to reflect the year change, and typically, NASA has preferred to do this while the shuttle is safely on the ground or docked to the space station.

Discovery's STS-133 mission has already been delayed since early November due to technical and weather-related issues. The shuttle's planned 11-day mission will deliver a storage room and Robonaut 2, a humanoid robot, to the International Space Station. Two spacewalks are also planned.

The mission will be the 39th and last flight for Discovery and is one of NASA's two final scheduled shuttle flights before the orbiter fleet is retired in 2011. NASA is hoping to launch an additional shuttle flight around June, but is still awaiting final funding approval from a congressional appropriations committee.

Still, Beutel emphasized that there are a lot of variables that could influence the decision-making process, and ultimately, the next launch attempt will be set when managers are fully confident they understand what caused the problems with the shuttle's external tank. ?

"It's not a clear cut process, but management is making smart decisions," Beutel said. "They're not being pressured by the schedule. It's all about when the data supports a launch."

• Gallery: Building Space Shuttle Discovery
• Video ? Space Shuttle Discovery: A Retrospective, Part 2, Part 3
• Space Shuttle Discovery's Retirement Plan in Limbo

You can follow SPACE.com Staff Writer Denise Chow on Twitter @denisechow.