NASA is targeting March for the next Space Shuttle mission (STS-121). The mission will be the second test flight to the International Space Station in the Shuttle Return to Flight sequence.
NASA Administrator Michael Griffin and Associate Administrator for Space Operations Bill Gerstenmaier made the announcement today at a news conference at the agency's headquarters in Washington.
"We are giving ourselves what we hope is plenty of time to evaluate where we are," said Administrator Griffin. "We don't see the tasks remaining before us being as difficult as the path behind us."
Based on NASA's self-imposed optimum lighting requirements, the earliest possible launch opportunity for the STS-121 mission is March 4, 2006. The Space Shuttle Discovery will be used for the mission, instead of Space Shuttle Atlantis.
Moving toward a no earlier than March launch for STS-121 will allow engineering teams more time to properly evaluate the issue of large pieces of insulating foam that came off Discovery's external fuel tank during launch last month.
Targeting March also allows the Space Shuttle Program to put itself into a better posture for future Shuttle missions to the Space Station. Changing Orbiters for the STS-121 mission enables use of Atlantis for the following mission, STS-115, which will resume assembly of the Station.
The switch frees Atlantis to fly the remaining Space Station truss segments, which are too heavy for Discovery, in 2006. By changing the Orbiter line up, the Shuttle program will not have to do two back-to-back missions with Atlantis, as previously scheduled.
"It really makes sense to move to the March timeframe," Gerstenmaier said. "We're looking at the Shuttle missions to support the most robust flight sequence for the Space Station and to make the whole sequence flow better. This extra time helps us make sure that all the work we need to do fits and that there are no other issues."
Discovery's recent mission, STS-114, and the STS-121 mission are test flights. They will enable NASA to evaluate new safety procedures and equipment, giving the agency greater confidence that the Shuttle can be flown safely through its planned retirement date of 2010.
The external fuel tanks at NASA's Kennedy Space Center in Florida will be shipped back to the Michoud Assembly Facility in Louisiana for tests and potential modifications.
For information about the STS-114 Return to Flight mission and future Shuttle flights, visit:
http://www.nasa.gov/returntoflight
For information about NASA and agency programs on the Web, visit:
http://www.nasa.gov/home/index.html
