Storm worries force early shuttle return

HOUSTON (Reuters) - Space shuttle Endeavour will come back to Earth a day earlier than scheduled because of worries about powerful Hurricane Dean, NASA said on Saturday.

Endeavour will undock from the International Space Station on Sunday and aim for a Tuesday landing at Kennedy Space Center in Florida, mission management team chairman Leroy Cain said. It had been set to return on Wednesday.

Dean was roaring through the Caribbean Sea with 150 mile per hour winds (240 kph) and expected to enter the Gulf of Mexico early next week.

Forecasters predict it will hit northeastern Mexico, but Cain said NASA could not take the chance it would turn north and force the evacuation of Johnson Space Center in Houston, where Mission Control is located.

"It would have been irresponsible for us not to take seriously this storm. It's a big storm and it's a serious storm," he said.

"We're trying to put ourselves in a posture to be able to get out of harm's way, with the people and the assets, in the event we get unlucky," said Cain.

He said landing could be postponed to as late as Thursday if weather is bad at Kennedy or alternate landing sites in California and New Mexico. Kennedy is not expected to be affected by Dean and forecasters expect good weather there, Cain said.

SHORTENED SPACEWALK

NASA's decision followed a day of preparations that included an abbreviated spacewalk by astronauts Dave Williams and Clay Anderson who performed chores to ready the space station for future additions.

The spacewalkers paused from their work as the spacecraft flew over Dean 200 miles below.

Television shots from space showed the storm's massive swirl of clouds, with the eye clearly visible.

"Holy smoke," Anderson said.

"Man, that's impressive," said Williams.

"Very. They're only impressive when they're not coming to you," Anderson said.

They finished up in about five hours, more than an hour ahead of the original schedule. Afterward, crews from the shuttle and space station bid each other farewell with hugs and handshakes, then closed the hatches between the two spacecraft to prepare for Sunday's departure.

The shuttle took off from Florida on August 8 and arrived at the station on August 10, carrying a metal beam that astronauts installed on the space complex in the first of four spacewalks.

NASA spent much of the mission considering whether a gouge in Endeavour's heat shield, caused by loose fuel tank insulation foam that struck the ship's belly at launch, needed to be repaired before the shuttle's fiery return to Earth.

After six days of deliberations, it decided on Thursday the 3-inch (7.6-cm) gash posed no threat and no fix was needed.

Shuttle Columbia was destroyed and seven astronauts killed in 2003 because of a heat shield break caused when a piece of flying tank foam hit the ship's wing at liftoff. The damage was not detected and Columbia disintegrated shortly before it was to land.

NASA wants to complete space station construction by 2010 when the shuttle fleet is to be retired.

Laboratories from Europe and Japan are scheduled to be installed on the $100 billion international project in December and in early 2008.