CAPE CANAVERAL, Fla. -- NASA has set May 31st for the next space shuttle launch.

Senior NASA managers have agreed to proceed as planned with Discovery's two-week trip to deliver a Japanese lab to the international space station.

A Russian Soyuz ship is always docked at the space station as an emergency "lifeboat" in case the crew needs it. But the last Soyuz that flew made an off-course, steeper-than-usual descent on April 19th.

One of the three astronauts returning in it ended up in the hospital with back pain. The Russian Space Agency is investigating.

NASA astronaut Gregory Chamitoff is flying up on Discovery and is supposed to remain at the space station for six months. He will replace another American, Garrett Reisman, who was dropped off in March.

Mission Control is at Johnson Space Center in Houston.

NOTE: Texas A&M graduate Michael Fossum will be aboard Discovery for this mission. His first mission to space was also on Discovery in July 2006.