The same storm system that sank an oil tanker off the coast of Spain grounded space shuttle Endeavour on Friday.

NASA halted the countdown nine minutes before launch because weather had not improved at either of the two emergency landing strips in Spain. Conditions were ideal in Florida with a picture-perfect, nearly full moon shining over the launch pad.

Launch managers said they would try again Saturday night, despite forecasts calling for more rain, wind, thick clouds and turbulence across the Atlantic.

"Appreciate the effort," launch director Mike Leinbach told the seven astronauts and his team. "But we're just not going to make it tonight."

It was the latest delay for a space station mission that already is nearly two weeks late because of an oxygen leak and a damaged robot arm. Friday night's postponement alone cost $750,000.

In 21 years of space shuttle flight, NASA has had to postpone launches only a few times because of bad weather at the overseas landing sites. The two military air bases in Spain would be used only if the shuttle developed engine trouble or some other emergency in the minutes following liftoff.

Endeavour should have departed for the international space station on Nov. 11, but an oxygen leak cropped up in the astronauts' oxygen supply system shortly before liftoff.

The leak was traced to a cracked hose. During the repairs, technicians accidentally rammed scaffolding into the shuttle's robot arm, causing minor damage.

Engineers concluded the arm would be sturdy enough to lift a 14-ton girder from the shuttle's payload bay for installation on the space station. Two of Endeavour's crew will go out on three spacewalks to hook up the structure.

One of the designated spacewalkers, John Herrington, will become the first American Indian in space. About 200 members of his tribe, the Chickasaw Nation, traveled to Cape Canaveral for the previous launch attempt, but could not return and held a ceremony back home in Ada, Okla., on Friday night.

Besides the $390 million girder, Endeavour will deliver a fresh three-man crew to the space station. The current residents have been on board since June.

One of the astronauts who will be moving in, Donald Pettit, was assigned to the mission just four months ago. He was originally the backup for Donald Thomas. But on Friday, NASA said Thomas was removed from the flight because of concerns about the amount of radiation he would have received.

"It was an assessment of the radiation exposure he would have gotten on a long-duration mission," said NASA spokesman Doug Peterson. Peterson said such assessments are based on the individual, his spaceflight experience and his personal background.

Thomas has flown four times in space for a total of 43 days. Astronaut Kenneth Bowersox has logged 50 days over four previous space flights but was not pulled from the mission. And their Russian crewmate, Nikolai Budarin, has spent 9 months in space, aboard his country's old Mir space station.

Cosmic radiation has always been a major medical concern facing astronauts who spend prolonged periods in space; it can raise the risk of cancer and other illnesses. It is believed to be one of the limiting factors for a mission to Mars.

Pettit, Bowersox and Budarin will remain on the space station for at least four months. They will replace astronaut Peggy Whitson and cosmonauts Valery Korzun and Sergei Treschev, who marked their 170th day in orbit Friday.

Whitson informed Mission Control on Friday night that all of the American food was gone — except for the vegetables.