Shuttle Endeavour mission delayed again by weather

By Irene Klotz

CAPE CANAVERAL, Florida (Reuters) - Lightning strikes and thunderstorms near the seaside launch pad forced NASA on Monday to delay yet again the launch of shuttle Endeavour on a mission to the International Space Station.

"The weather has just bitten us again," launch director Pete Nickolenko radioed to the Endeavour crew, as the spaceship's liftoff was postponed for the fifth time in about a month.

Endeavour had been scheduled to blast off at 6:51 p.m. EDT

(2251 GMT) on a mission to install a Japanese-built outdoor research platform at the space station. The launch was rescheduled for 6:03 p.m. EDT (2203 GMT) on Wednesday.

Two launch attempts last month were scuttled by hydrogen fuel leaks. A third attempt ended on Saturday when NASA ordered checks of the shuttle's electrical systems following a spate of lightning strikes and Sunday's launch was canceled due to poor weather.

NASA is trying to complete construction of the $100 billion orbital outpost, a project of 16 nations, by September 30, 2010, so it can retire the shuttle fleet and ramp up development of replacement ships that can journey to the moon and other destinations farther from Earth.

Endeavour's cargo includes the Japanese-built platform that is to be mounted to the front of the $2.4-billion Kibo lab where it will serve as an outdoor perch for science experiments that need to be exposed to the open environment of space.

Experiments on the platform can be installed and retrieved remotely with a robotic arm, eliminating the need for time-consuming and potentially risky spacewalks by station crewmembers. The first two sections of Kibo were attached to the station in 2008.