Shuttle launch moved to Saturday

Cape Canaveral -- NASA called off Thursday's launch of space shuttle Atlantis after a pair of fuel gauges in its big external tank failed to work properly, a recurring problem ever since the Columbia disaster. Now managers are hoping to launch the shuttle on Saturday.

Preliminary indications were that the problem might be with an open circuit rather than the gauges themselves perhaps a spliced line or bad connector which would be easier to fix. Mission managers spent several hours in meetings discussing how to best proceed with the countdown. They decided to forgo a Friday launch attempt to give engineers more time to figure out what was wrong and resolve the trouble.

Launch director Doug Lyons said he was hopeful the launch team would get another crack at getting Atlantis off the pad before the end of next week. If the shuttle can't launch by next Thursday or Friday, NASA would have to wait until early January to launch Atlantis.

The fuel tank sensors are part of a critical backup system to ensure that the shuttle's three main engines don't shut down too soon or too late during liftoff, a potentially catastrophic problem.