Space agency managers worried that the storm would move toward Houston and force them to evacuate to a smaller-staffed makeshift control center at Cape Canaveral, Florida.

The Endeavour crew prepared to land on Tuesday as a precaution.

"Endeavour departed," space station commander Fyodor Yurchikhin said as the shuttle pulled away.

The shuttle crew had been at the orbiting outpost since 10th August.

In that time, they attached a new truss segment to the station, delivered cargo and replaced a failed gyroscope, which controls the station's orientation.

They have had to compress their schedule to get ready for the early undocking.

Teacher-turned-astronaut Barbara Morgan, who was Christa McAuliffe's backup on the tragic 1986 Challenger mission, was scheduled to talk to students in Massachusetts on Sunday, but that event was canceled.

A spacewalk on Saturday was shortened so the astronauts could wrap up their work at the station.

During that jaunt, the spacewalkers saw the eye of the enormous hurricane swirling in the Caribbean.

The astronauts also skipped flying around the station after undocking to take pictures of the complex, an exercise NASA likes shuttles to do if the schedule and fuel supply permit.

Although it was uncertain whether Dean, a Category 4 storm, might strike the Texas coastline later this week, NASA managers said it would be irresponsible not to cut the mission short, especially since most of the tasks had been completed. - DDNEWS