Space shuttle launch delayed

Lightning forced Nasa to delay the space shuttle Endeavour's planned launch yesterday by at least a day, the latest blow to the seven-astronaut mission.

Nasa announced the delay with just nine hours to go before liftoff, citing 11 lightning strikes near the Cape Canaveral launch site during a powerful electrical storm on Friday evening.

"The launch is scrubbed for at least 24 hours," Nasa spokesman George Diller said.

"This delay will give technical teams additional time to evaluate lightning strikes at Launch Pad 39A that occurred during Friday's thunderstorm."

There was "no damage found on the shuttle or on the pad systems," Diller said, although scientists are now examining whether the inclement weather could have caused other problems.

Nasa said the lightning strikes were within 0.3 nautical miles of the pad, with several of them striking the wiring system designed to protect the shuttle from taking direct lightning hits.

The hold-up spells more tension for Endeavour's seven-member crew and the Nasa boffins who have now been forced to abandon the shuttle's launch three times.

Two previous launch attempts were scuttled by potentially hazardous fuel leaks, apparently caused by a misaligned plate linking a hydrogen gas vent line with the external fuel tank.

Yesterday's delay came before Nasa could begin the process of pouring two million litres of liquid hydrogen into the tanks at very low temperatures, which engineers would have eagerly monitored for more leaks.

But the bad weather had been expected. Shuttle weather officer Kathy Winters earlier warned that showers, thunderstorms and icy clouds could interfere with the final countdown.

There had been 60 per cent chance of inclement weather conditions "prohibiting" the shuttle's latest launch attempt, she said.

Despite the warnings, Nasa late on Friday removed the shuttle's giant scaffolding-flanked shroud, heralding the final preparations for the beginning of Endeavour's voyage to the International Space Station.

The crew - including six Americans and one Canadian - had been expected to leave Cape Canaveral for a 16-day voyage to the ISS.

There they were expected to install a platform for astronauts to conduct experiments in the vacuum of space, 350 km above Earth's surface.