Over the 68 years that humans have been launching satellites into space, we have created a whole load of space junk.
Why? Because when a satellite, or other piece of machinery that we have put into space, is no longer useful, we have no way of returning it to Earth. Instead, it just sits, there gradually breaking down in orbit.
Also known as space debris, this comprises not only satellites, but old bits of machinery, the remains of failed rockets, as well as fragments and objects that astronauts have dropped while on space walks.
In the past this might not have seemed like much of a problem: space flight was so rare and satellites were expensive and not a commonplace piece of technology that we relied on.
But now? Not content with our impact on the environment on our own planet, we are littering the environment in space too.
Why is this a problem? Well think about it. All that junk, bits of metal, objects like screwdrivers, floating fuel and other particles are orbiting the earth. And they’re not doing so slowly: space debris is travelling at up to 18,000 miles per hour, held in orbit by the Earth’s gravitational pull.
As more and more space debris accumulates, it poses an increased problem for space travel – as well as for those of us living back on earth.
While the dangers to astronauts are obvious – they could be struck by space debris not only while living on the International Space Station and travelling to and from it, but while on space walks and doing necessary maintenance to the ISS too.
But space junk can also damage our satellites. When impacted by a collision, damage to satellites can affect everything from our GPS to our cell coverage. And that’s before we even consider the damage that lots of orbiting objects can do to our atmosphere and our ozone layer.
That’s why scientists at Kyoto University, Japan, have acted to create a satellite that will leave no space junk in its wake.
How? Well this satellite is made of wood.
Known as LignoSat, this satellite – which has recently been launched into space on an unmanned SpaceX rocket – is built from timber which scientists believe will burn up when it re-enters the atmosphere. This means that instead of floating abandoned for eternity, this satellite will cease to exist when it is rendered no longer useful.
Once it reaches the ISS, the satellite will be prepared for release by astronauts into outer space. It is expected that this will happen in December, after which point scientists back on earth will be able to collect data to measure its success.
Experiments will help researchers to understand the durability of the satellite, including how it responds to the extreme temperatures in space.
Though this is just one satellite for now – and a small one at that, measuring just 10cm in width – the scientists hope that this satellite will be the first in a more eco-friendly range of space technology.
If you think that’s impressive, check out this story about a “goldmine” of lithium that was found in the U.S. that could completely change the EV battery game.