Hurricane Threat Could Force Early Space Shuttle Landing

This story was updated at 8:08 p.m. EDT.

HOUSTON -- The looming threat of Hurricane Dean could force NASA's shuttle Endeavour to land Tuesday, one day earlier than planned, mission managers said Friday.

Endeavour is currently slated to land Wednesday after a 14-day construction mission to the International Space Station (ISS), but the approach of Hurricane Dean has prompted concerns that affect NASA's Houston-based shuttle and space station control centers here at the Johnson Space Center (JSC).

"We'd really like to protect an option to end the mission on Tuesday," said NASA mission management chair LeRoy Cain late Friday.

Endeavour's STS-118 crew is currently scheduled to land at NASA's Kennedy Space Center (KSC) in Cape Canaveral, Florida at 12:52 p.m. EDT (1652 GMT) Wednesday. NASA has two landing opportunities at that site on Tuesday, beginning at 12:30 p.m. EDT (1630 GMT) with the second window opening about 30 minutes later.

For a Tuesday landing, Endeavour astronauts would have to undock from the ISS late Sunday to complete their construction flight to the orbital laboratory.

Cain said mission managers are also studying options to cut short a planned Saturday spacewalk outside the ISS for Endeavour's STS-118 crew.

"It's not ideal," shuttle commander Scott Kelly told reporters Friday of a possible early return. "We could potentially undock the day after the spacewalk and come home a day early."

Alternate landing sites

Hurricane Dean is currently in the Caribbean Sea on course for the Yucatan Peninsula, with National Hurricane Center forecasts predicting its arrival in the Gulf of Mexico on Wednesday -- when Endeavour is slated to land -- and potentially impact the Texas coast.

"The center will have to make a decision in the mid-Sunday to mid-Monday on whether or not to close," Cain said of JSC. But the decision to land Endeavour early would have to be made well before that, he added.

If NASA's mission control operations are forced to close here at JSC, the space agency would send about two dozen critical flight controllers to a backup Mission Control site at KSC, Matt Abbott, NASA's lead shuttle flight director, told reporters in an afternoon briefing.

Space station flight controllers, too, are reviewing their procedures should the hurricane force an evacuation of Houston and Mission Control. In September 2005, the NASA closed its ISS Mission Control during Hurricane Rita, transferring primary control of the station to its Russian Federal Space Agency mission operations center near Moscow, with a backup team of U.S. flight controllers primed outside Houston.

But NASA hopes none of those contingencies will be required, since its Mission Control centers in Houston are the best equipped to oversee spacecraft in Earth orbit.

"Our objective is really to get the mission completed, first and foremost, from here in Houston," Abbott said.

To prepare for a possible Tuesday landing, Cain said mission managers are preparing to call up two additional landing sites for Endeavour in the event of an early return.

Support teams are expected to ready NASA's backup shuttle landing sites at California's Edwards Air Force Base and the White Sands Space Harbor in New Mexico for the possibility of a Tuesday return for Endeavour, he added.

"It's really important that we keep our options open as long as it's practical," Abbott said. "We've been watching this storm kind of brewing for a couple of days and everyone has been aware that it's developing ? we need to be prepared to respond."

NASA is broadcasting Endeavour's STS-118 mission live on NASA TV. Click here for mission updates and SPACE.com's NASA TV feed.

• VIDEO: STS-118 Mission Profile: SPACEHAB
• VIDEO: Endeavour Shuttle Tile Damage
• Complete Space Shuttle Mission Coverage