Shuttle Atlantis Launch Delayed

NASA called off Thursday's launch of space shuttle Atlantis after detecting problems with a pair of fuel gauges in the shuttle's external tank.

Shuttle managers said they would try again Friday—if the problem can be solved before then.

Engineers were testing the four engine-cutoff sensors in Atlantis's liquid hydrogen tank, and two of them failed.

Even though they were commanded to indicate the tank was empty, the two kept showing the tank was full, said NASA spokesman Paul Foerman.

At least three of the sensors must work properly to proceed with a launch.

Officials said the problem might be related to wiring and connectors, rather than the sensors themselves. It was not immediately clear how any repairs might be made.

The sensors are critical to ensure that the shuttle's three main engines don't shut down too soon or too late during liftoff. Problems with the sensors have delayed shuttle launches before, most recently in September 2006. The trouble began cropping up following the 2003 Columbia disaster.

NASA had been hoping for an on-time takeoff. Each of the year's three previous shuttle countdowns had ended with an on-the-dot departure.

Atlantis is loaded with Europe's long-awaited space station lab, named Columbus.

The seven astronauts had yet to board their spaceship when the delay was announced.

About 750 Europeans connected to the scientific laboratory—a 2 billion U.S. dollar project begun nearly a quarter-century ago—were in town for the launch and had begun gathering at the space center.

It was yet another disappointing flight delay for the European Space Agency, which has been working on Columbus for more than 22 years.

Columbus is "our cornerstone, our baby, our module, our laboratory," Alan Thirkettle, the European Space Agency's station program manager, said Wednesday.

Columbus will be the second laboratory added to the international space station. NASA's Destiny lab made its debut in 2001, and Japan's huge lab Kibo—which means "hope"—will go up in three sections beginning on the next shuttle mission in February.

Once Columbus arrives at the space station, scientific work can start almost immediately inside the lab, which is essentially packaged and ready to go.

Aside from the interruption caused by the 2003 Columbia tragedy, the actual building of the space station in orbit has gone well, NASA Administrator Michael Griffin said.

That's in stark contrast to the space station's planning and development, which dragged on for years and contributed to Columbus' prolonged grounding.

"We the United States, as the senior partner in the space station coalition, did not plan it well," NASA Administrator Michael Griffin said Thursday, on the eve of Columbus' originally scheduled launch. "It has taken far too long, and I'll just leave it at that."

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