It's down to the wire for space shuttle launch
Cape Canaveral (Fla.), Sept 9: Hoping for good weather and better luck, NASA started fueling the space shuttle Atlantis today for a last-ditch attempt to launch a mission to resume construction of the International Space Station.
Liftoff is targeted for 11:15 am (1515 GMT) from the Kennedy Space Center in Florida on the final day of the shuttle's two-week launch window. Weather conditions are forecast to be favorable for liftoff.
NASA has been trying to get the shuttle and its six-member crew off the launch pad since August 27.
Another launch delay would force NASA to put off additional launch attempts until Russia completes a mission to the station that is scheduled to begin next week.
Weather issues bedeviled the US space agency during its first week of launch attempts. A massive bolt of lightning struck the launch pad, prompting a two-day review to check the shuttle and ground equipment. Then the spacecraft was temporarily removed from the seaside pad because of threatening winds from a tropical storm.
This week's delays were caused by technical concerns: an unusual voltage spike in one of the shuttle's onboard electricity generators and the unwelcome return yesterday of a mysterious fuel sensor problem that dogged NASA last year as it attempted to fly the first shuttle mission since the 2003 Columbia disaster.
The sensor is one of four that serve as a backup system to make sure the shuttle's engines shut down before the tank runs out of fuel, avoiding a potentially catastrophic situation.
A half-million gallons of cryogenic propellants began flowing into the shuttle's 47-metre-tall fuel tank around 1:15 am (0515 GMT).
With Atlantis' flight, NASA plans to restart construction of the International Space Station, which has been on hold since the Columbia accident. The crew is to deliver and install a 2 million solar power module.
About half of the 0 billion orbital outpost remains in pieces at the Kennedy Space Center awaiting rides on the shuttles.
NASA plans to stop flying the space shuttles by 2010 as the United States moves to a new spacecraft to fly crews to the space station and the moon.
The station components were all designed, however, to be launched only on the shuttle, putting pressure on NASA to operate its three-ship fleet consistently and safely so the station can be finished.