Environment
Space debris to be cleared using lasers, Australian scientists say
Australian scientists have started working on a project to ‘zap’ space debris floating in orbit using lasers positioned on Earth. They hope this will reduce the threat to astronauts and satellite networks.
The scientists say that there are more than 300,000 pieces of debris in space, including screws and bolts, large parts of rockets, spatulas and gloves. It is estimated that there are about 29,000 objects that are 10cm or larger.
Although the project sounds like science fiction, the Australian team say it is necessary as the threat posed by space junk is growing.
“There are hundreds of thousands of pieces of space junk in orbit that are big enough to do serious damage to a satellite or space station”, said Matthew Colless, director of Australian National University’s Research School of Astronomy and Astrophysics.
“Everywhere humans have been in space, we leave some trash behind. We now want to clean up space to avoid the growing risks of collisions and to make sure we don’t have the kind of event portrayed in [2013 film] Gravity.”
Australia is now working with NASA to track space debris using an infrared laser at Mount Stromlo Observatory. Some $20m (£10.9m) from the Australian government and $40m (£21.7m) in private investment will be used to set up a Co-operative Research Centre (CRC) and develop stronger lasers.
The projects ultimate aim will be producing accurate technology that can slow object’s orbit, allowing the space junk to fall back into the atmosphere, where it would burn up harmlessly. Colless said the lasers are likely to be operational in 10 years.
“There is now so much debris that it is colliding with itself, making an already big problem even bigger”, said CRC chief executive Dr Ben Greene.
“A catastrophic avalanche of collisions that would quickly destroy all satellites is now possible.”
These satellites provide essential services, such as communication, television and navigation. It is estimated that to replace all of them would cost around €100 billion (£83 billion). The financial impact on the global economy of losing such services would be even higher.
There have already been four major collisions in low-Earth orbit. The most serious was in 2009, when an Iridium Communications satellite collided with a defunct Russian Space Forces satellite at over 25,000 miles per hour.
Meanwhile in April 2012, a $690m (£412m) NASA telescope only narrowly avoided a collision with another dead Russian satellite when NASA engineers pulled off an emergency evasive manoeuvre.
Heiner Klinkrad, head of the European Space Agency’s (ESA) space debris office, said in April last year, “Our understanding of the growing space debris problem can be compared with our understanding of the need to address Earth’s changing climate some 20 years ago.
“While measures against further debris creation and actively deorbiting defunct satellites are technically demanding and potentially costly, there is no alternative to protect space as a valuable resource for our critical satellite infrastructure.”
Further reading:
Space junk: the abuse of the abyss