NASA satellite
Australia will work with other nations to develop an international code of conduct for behavior in outer space backing a proposal by the European Union. NASA

A NASA defunct six-ton satellite the size of a bus is heading towards earth and is expected to crash within the next 24 hours, but experts have no idea where it will land as its orbit is slowly decaying until gravity finally pulls it down as a fiery meteor.

Reports seem to indicate that 26 large pieces of the NASA Upper Atmosphere Research Satellite (Uars), the heaviest about 330 pounds, are expected to survive all the way and hit the surface.

However NASA has pointed out that satellites as large as Uars re-enter Earth's atmosphere about once a year and there have been as of yet, no reports of any deaths or injuries to people from falling debris.

The agency has thus assured the odds of a piece of the Uars debris striking a person is about one in 3,200.

The agency has instead insisted that it expects most of the probe to burn up in the atmosphere and say the debris are likely to fall into an ocean or land in an uninhabited region of Earth.

Moreover, the probe is being tracked by radar stations and experts around the world so its course can be pre-empted.

Flight Lieutenant Mike Farrington who had been monitoring the 35ft long satellite since its launch however warned that due to its shape, size and speed, the probe has proven difficult to track.

"There's a great deal of uncertainty over where it will re-enter. Due to the irregular size and shape of this object it's impossible to say.

"These things move at about 7.5 kilometres (4.6 miles) per second in space and something moving at that speed is very difficult to predict.

"We've got some world class analysts here who've been working round the clock.

"But it's impossible for anyone using any of the resources anywhere across the globe to actually predict when and where this object will land."

The satellite was first launched in 1991, and has been monitoring chemicals in the atmosphere, slowly losing altitude since completing its mission in 2005.

It is not the first time the satellite has caused a stir as in 2010 it forced the International Space Station into a collision avoiding manoeuvre.

Despite reassurance from NASA and optimistic odds, cosmic junk debris can still potentially be dangerous so watch this space-literally.