Utah rocket boosters derailed

Last Friday, two axles on one car came off the tracks for unknown reasons about 60 miles west of Salina, Kan., while the train was traveling at less than 20 mph, Herring said. The train was back on the tracks after several hours, the spokesman said.

A spokesman for the manufacturer, Bryce Hallowell, said the rocket company had two employees and a contractor on the train Wednesday, and they suffered non-life-threatening injuries. The other three apparently worked for the rail company.

The train was with Union Pacific when it left Utah but was believed to have transferred to Meridian and Bigbee of Meridian, Miss., before the derailment. A call to Bigbee headquarters was not immediately returned.

"It's our understanding the motors are stable," Hallowell said. After an inspection, he said, the company will work with the railroad to safely remove them.

NASA officials said two locomotives, a train car behind them, and one car with a shuttle booster overturned. The fuel in the rocket, aluminum perchlorate, has the consistency of a rubber eraser and there was no danger of it igniting, according to NASA.

Hallowell said the train was taking the same route to the Kennedy Space Center that has been used for 30 years or more. The train trip can take more than a week.

The accident was the latest in a run of bad luck for the space agency.

In February, astronaut Lisa Nowak was arrested on charges of trying to kidnap a romantic rival. Later that month, a freak hail storm caused thousands of dents in space shuttle Atlantis' external tank as it sat on the launch pad, delaying the flight for months.

Last month, a worker at NASA's Johnson Space Center in Houston shot a colleague to death and then killed himself.