CAPE CANAVERAL, Fla. Shuttle Atlantis will be gassed up at a floodlit launch pad Thursday night as NASA mounts a final push toward a planned sunrise liftoff for the agencys first International Space Station maintenance crew.

The 18-story spaceship and its crew -- which includes six American astronauts and a Russian cosmonaut -- are scheduled to take off from Kennedy Space Center (KSC) during a short 10-minute launch window that extends from 6:07 a.m. to 6:17 a.m. Eastern Daylight Time (10:07 to 10:17 GMT) Friday.

NASA is targeting the launch for 6:12 a.m. EDT (10:12 GMT) and forecasters say there is absolutely no chance that predicted weather will force a delay in the flight, which was cancelled three times in late April due to stiff winds in Florida and at emergency landing sites overseas.

Mission managers, meanwhile, say launch preparations are continuing without problems.

"The shuttle vehicle is ready to go. The flight and ground teams are all ready to go fly," said senior shuttle program manager Bill Gerstenmaier. "There are really no problems that were working. Everything looks really good."

The next big event: A three-hour fuel-loading operation slated to begin at 9:19 p.m. EDT tonight (Friday, 01:19 GMT).

Engineers at that time will begin pumping more than 500,000 gallons (2.3 million liters) of liquid hydrogen and liquid oxygen into the shuttles 15-story external tank, a burnt orange fuel reservoir that will feed Atlantis three main engines during an 8.5-minute climb into orbit.

"The shuttle vehicle is ready to go. The flight and ground teams are allready to go fly... Everything looks really good."

The seven shuttle astronauts, meanwhile, have a long night ahead of them. Led by veteran mission commander Jim Halsell, the astronauts will don their partial pressure flight suits around 1:52 a.m. EDT (05:52 GMT) Friday and then head out to launch pad 39-A about a half-hour later. The astronauts will start boarding Atlantis just before 3 a.m. EDT (07:00 GMT) and the shuttles hatch will be closed for flight about 4:07 a.m. EDT (08:07 GMT).

Once in orbit, the astronauts will head toward a 12:32 a.m. EDT (04:32 GMT) Sunday docking at the International Space Station, which now is made up of an aging Russian space tug and an American docking module.

The job at hand: repairing station electrical systems that have exceeded their warranty, mounting construction cranes outside the outpost and nudging the unfinished lab -- which has been sinking slightly due to increased solar activity -- into a higher orbit.

The 9-day, 20-hour mission is expected to kick off a hectic six months for NASAs space station construction project, stalled now for nearly a year by delays in the long-awaited launch of a crucial Russian command-and-control module that will double as crew living quarters.

The so-called service module, dubbed Zvezda, or "Star" by the Russians, now is slated to blast off from Baikonur Cosmodrome in Kazakhstan on July 12. Its launch will pave the way to at least two more station construction missions and the arrival of the outposts first full-time crew later this year.

"Weve got a busy year ahead of us," said Robert Cabana, NASAs space station project manager for international operations. "This is our year to get a functional space station on orbit with a crew living on board doing science."

An on-time Atlantis launch Friday would lead to a 2:19 a.m. EDT (06:19 GMT) landing back at KSCs 3-mile shuttle runway.