The world’s navigation and communication networks are at risk of being brought down by a “catastrophic avalanche” of space junk, researchers have warned.
The rapid build-up of space junk orbiting Earth is a serious threat to satellites, which are crucial for everything from global positioning systems and mobile phone calls to television broadcasts and weather forecasts.
The International Space Station is the largest object ever constructed by humans in space.
And destructive junk doesn’t need to be big. Chief executive of the Space
Environment Research Centre Ben Greene said a thumbnail-size piece of junk travelling at 10 kilometres a second could take down a satellite.
“The most pessimistic mathematical model says that we are within five years of having a 50-50 chance that a catastrophic avalanche of collisions will occur any day,” Dr Greene said. “The most optimistic model says we’ve got 25 years.”
Dr Green said the avalanche scenario refers to an event which wiped out all satellites – which would compound the problem as it would create yet more space junk.
More than $A1 trillion worth of global space infrastructure currently orbits the Earth, including about 600 working satellites.
Meanwhile, an estimated 170 million pieces of man-made space junk are in orbit. About 300,000 items are larger than 10 centimetres.
This month, British astronaut Tim Peake tweeted a picture of a crack in a window of the International Space Station which was caused by a space-junk strike.
“Glad it is quadruple glazed!” he wrote.
The space junk that caused the damage to the International Space Station is believed to have been a small flake of paint.
Congestion of space is becoming an increasingly urgent problem for international scientific and diplomatic communities.
Up to 30,000 objects are launched into space each year, with the US the biggest contributor.
As the volume of space junk increases, so does the risk of a collision.
“And as you get more collisions, you get more space junk, which increases the possibility of another collision,” Dr Greene said. “It just escalates.”
He said the junk did not degrade and continued orbiting long after its useful life had ended.
Identifying space junk and being able to track objects in orbit as well as predict movements was crucial for protecting vital space infrastructure. Ground-based lasers are among the tools which could manage space junk, Dr Greene said.
Researchers have also floated the idea of attaching lasers to the International Space Station to detect and destroy space junk before a collision occurs.
Read the article at The Sydney Morning Herald.