With 60 percent chance of good weather forecast by meteorologists, and the four days behind-scheduled Discovery launch now scheduled for liftoff at 11:59 p. m. EDT (0359 GMT on Saturday), NASA Friday night filled the space shuttle's fuel tank with more than 500,000 gallons, or 1.9 million liters, of liquid oxygen and liquid hydrogen.

Earlier this week, launch delays, one after the other, resulted from a malfunctioning 8-inch liquid hydrogen valve. However, during the Friday fueling, the valve worked normally, thereby averting a waiver from the engineers.

While it was Discovery's initially-scheduled Tuesday launch try was marred by stormy weather as well, near the launch pad, the second attempt was called off during fueling Tuesday night for a Wednesday morning launch, mainly due to the valve trouble.

The Discovery space shuttle, on a 13-day flight to deliver new laboratory equipment, supplies and spare parts to the International Space Station, has a seven-astronaut crew, including commander Frederick Sturckow, pilot Kevin Ford, flight engineer Jose Hernandez, Patrick Forrester, John "Danny" Olivas, European Space Agency astronaut Christer Fuglesang, and space station flight engineer Nicole Stott.

The space station - nearing completion late next year or early 2011, almost after a decade of work - will have had the US, Russia, Europe, Japan and Canada spent nearly $100 billion on the outpost; with seven more visits to go, including the current Discovery mission!