”NASA's new space plan, unveiled in February as part of President Obama's 2011 budget proposal, calls for the cancellation of the agency's Constellation program in charge of building new rockets and spaceships to replace the aging space shuttle fleet. NASA plans just four more shuttle missions – one of which is under way now – before the fleet is retired in the fall.”

http://www.space.com/news/nasa-centers-new-assignments-100408.html