The falling NASA satellite passed by Australia late Friday afternoon, said astronomers who have been keeping track of its descent.

NASA expects the Upper Atmosphere Research Satellite to crash back to Earth within the next 24 hours but hasn't been able to pinpoint where it will land. So far the possible landing area covers all continents but Antarctica.

Astronomical Society of Victoria spokesman Perry Vlahos said the satellite made a direct pass over Melbourne just before 4 p.m., according to tracking Web sites and information from NASA. The satellite, which is about the size of a bus, was not visible to the human eye since it was still 100 km above the ground.

"It's a little difficult to ascertain where it will come down because there are so many variables involved, but it will definitely come down in some part of the world," Vlahos said.

"You couldn't see anything. It's still not quite ready to enter the atmosphere in a big way, but it isn't a long way up, probably 100 kilometers above us."

The UARS is now falling back to Earth after it was decommissioned in 2005 after 14 years in service. NASA scientists are expecting the satellite to break into pieces when it re-enters the atmosphere, leaving only 26 fragments to survive. The surviving pieces could include the titanium fuel tanks, beryllium housing and stainless steel batteries and wheel rims.

NASA has assured the public that there is little chance of the debris hitting anyone. There has never been a confirmed report of an injury from falling space junk.

Meanwhile, an Australian town that survived falling debris from a NASA spacecraft decades ago believes lightning could strike twice.

The town of Esperance in Western Australia was hit with debris from the Skylab in 1979. The town fined the U.S. for $400 for littering which was eventually paid for after 30 years by a U.S. radio station.

Esperance Shire chief executive Malcolm Osborne said the town council wouldn't fine the U.S. this time if any space junk lands on their town again.

"It was a lot of fun at the time and it gave the whole thing a bit of a human element," Osborne told the Sydney Morning Herald.

"It probably put Esperance on the map a bit as well."