SHUTTLE GROUNDED BY STORMS AGAIN

Nasa said it would try again early on Wednesday evening, after taking a one-day break.

In a scene nearly identical to Sunday, launch managers halted the countdown just minutes before Endeavour and seven astronauts were supposed to blast off.

This time, storms packed with lightning popped up on opposite sides of the launching site, one after the other, close enough to violate Nasa's safety rules.

Endeavour has been grounded for an entire month now, first by leaks, then storms.

"The weather has just bitten us again," launch director Pete Nickolenko informed commander Mark Polansky and his crew aboard Endeavour. "So sorry about that."

"We understand," Mr Polansky replied. "That's the nature of our business, and like I said before, when the time is right, we'll be here, we'll be ready."

If the shuttle is not flying soon, it will have to wait until July 26 in order for Russia to launch supplies to the space station. As it is, Nasa will have to rearrange the astronauts' schedule in orbit if they launch on Wednesday. A final try on Thursday - not yet approved - would mean eliminating one of the five planned spacewalks and shortening the flight.

Endeavour needs to be out of the way before Russia's unmanned cargo ship can dock.

Forecasters expect a 60% chance of favourable weather for Wednesday's try, scheduled for 6.03pm (2303 BST).