If you’re asked the question “What is orbiting the Earth?”, the first answer to come to your mind might be “The Moon”. Another answer could be “The International Space Station” or a number of other television or GPS satellites. If you stop for a moment and think about it, you will realise that for people to be able to have global network coverage, there must be a very large number of satellites surrounding the Earth, careful moving around each other. But these aren’t the only things bouncing around in our exosphere. The current count of trackable “space junk”, the term for assorted space debris, is over 500,000, and this is creating a massive negative impact on the future of space travel.
Space junk is mainly artificial, caused by leftover bits of rockets and space stations that have fulfilled their purpose and are abandoned above the planet, but some is natural, such as broken bits of meteoroids that never escaped Earth’s gravitational pull. Over 20,000 pieces of space debris are larger than a cricket ball and can travel up to 17,500 miles per hour, which causes serious threats to the important machines and people in space. Even the 500,000 pieces of marble-sized junk have been known to seriously damage strong satellites. The smallest fleck of paint, travelling at extreme high speeds in space can smash the window on a space station. On top of all the trackable debris, NASA is aware of millions more microscopic leftovers.
The current count of trackable “space junk”, the term for assorted space debris, is over 500,000, and this is creating a massive negative impact on the future of space travel.
This is not a new threat. We have been aware of the dangers of space debris since satellites were first sent into space. NASA has listed a few examples of times when abandoned equipment, or failed experiments have worsened the problem:
“In 1996, a French satellite was hit and damaged by debris from a French rocket that had exploded a decade earlier.
On Feb. 10, 2009, a defunct Russian satellite collided with and destroyed a functioning U.S. Iridium commercial satellite. The collision added more than 2,000 pieces of trackable debris to the inventory of space junk.
China’s 2007 anti-satellite test, which used a missile to destroy an old weather satellite, added more than 3,000 pieces to the debris problem.”
So what can be done to clean up the exosphere and renew the safety of space exploration? The first step is more advanced tracking. NASA and the Department of Defence are working together to create a better tracking mechanism in order to accurately predict impending crashes. Currently, though, the only option to avoid these predicted crashes is to literally move out the way in a “debris avoidance maneuver”. If a space station is going to get hit and isn’t able to move out of the way, the crew is moved into the Soyuz spacecraft, used to move humans to and from the station, which would then become a lifeboat in the case that the collision seriously damaged the station or any of the life support systems.
Locally, the Surrey Space Centre at the University of Surrey is working on a spacecraft, RemoveDebris, which is designed to test methods of netting and harpooning space junk. It will be launched from the International Space Station and release its own debris, which it will then clean up. It has also been designed to burn up on reentry into the atmosphere, to prevent the craft itself from becoming a problem. While this may help remove some of the larger, more critical pieces of debris, the millions of microscopic remains will continue to remain in orbit with no plan or clear way of removing them.