When you look into the night sky to marvel at the stars and ponder the vast, unknown chasm that is our universe, you may not spare a thought for what else is up there. Not UFOs, of course — space debris.
Yes — there are currently around 20,000 fragments of space junk orbiting the Earth. Pieces of old satellites, used rocket stages and fragments from collision, erosion and disintegration — they’re all floating up there.
Closer to Earth, below 2000km, there are around 300,000 pieces, made up of rocket motors, paint flakes, frozen coolant and more.
Now, Stuart Grey, a lecturer at University College London, has created a video to show how this junk has accumulated. Starting in 1957, when Sputnik first flew, the video shows how collisions and increased space traffic have caused a rapid increase in space debris.
These loose items don’t just look messy, however. Travelling around the Earth at around 17,000mph, they pose serious risk to astronauts and satellites also in orbit. Most unmanned orbits are protected by shields, preventing major damage, but low-mass impacts can cause serious damage by crafts powered by solar panels.
You may not be safe down on land, either — according to Nasa, around one piece of debris has fallen to Earth everyday for the last fifty years.