Space shuttle Endeavour stands ready on launch pad 39A as final preparations for it's launch are finalized at the Kennedy Space Center in Cape Canaveral, Fla., Thursday, Feb. 4, 2010. Endeavour, with a crew of six astronauts, is set for an early morning launch Feb. 7, on a mission to the International Space Station.(AP Photo/Terry Renna)

(AP) -- NASA has cleared space shuttle Endeavour for liftoff Sunday.

Mission managers gave the go-ahead Friday, as forecasters offered up an improved forecast. The chance of good launch is now 80 percent.

Shuttle managers acknowledged that many at NASA are still in shock over this week's space exploration shake-up. But they said the work force remains focused on a safe flight for Endeavour.

President Barack Obama has ordered a new course for NASA, ditching the back-to-the-moon program of the previous administration. Instead, Obama is proposing more research that could have heading to the asteroids or Mars.

Endeavour is delivering a new room and observation deck to the .