satellite, GGSE-4, raining debris in Earth’s orbit, according to leading space expert Dr Brad Tucker from The Australian National University (ANU).

The potentially collision will take place around 11am AEDT Thursday.

“This is a really close encounter, as these two big hunks of space junk are expected to come within 15 to 30 metres of each other. According to LeoLabs, which tracks space debris, the current prediction is a one in 100 chance of a collision,” said Dr Tucker from the ANU Research School of Astronomy and Astrophysics.

“If they collide, they could produce tens of thousands of pieces of debris. LeoLabs predicts they could smash into each other over Pittsburgh in the United States.

“In 2009, an old Russian Cosmos satellite crashed into an Iridium phone satellite.

“Currently, the US air force and other groups track objects up to about 10–15 centimetres wide.”

The Space Environment Research Centre (SERC), which has its headquarters at ANU Mount Stromlo campus, is working on tracking objects down to about one centimetre – of which there are hundreds of thousands currently orbiting the Earth.

SERC involves ANU, RMIT University and industry partners EOS Space Systems, Lockheed Martin, among other institutions.

“The centre is also working on using high-powered infrared lasers to push these small bits out of their current orbit and prevent future collisions,” Dr Tucker said.

ANU researchers, including Professor Céline d’Orgeville, are working on a technology called laser guide star adaptive optics to help make it safer to navigate around space junk.

“A laser guide star creates an artificial star in a part of the sky where there is no bright star and allows astronomers and space scientists to make scientific measurements,” said Professor d’Orgeville, Adaptive Optics Group Manager at the ANU Research School of Astronomy and Astrophysics.

“In addition to laser guide stars, we use lasers to measure where the satellite or the debris is in space, and predict where they’re going to be in future.

“Laser guide star adaptive optics were developed initially for ground-based astronomy, but it was realised the same technology can be used to address the problem of space debris.”