Space junk such as broken spacecraft and inactive satellites (illustration) adds to mounting congestion in Earth’s orbit. Credit: European Space Agency/SPL
There’s an awful lot of stuff orbiting Earth, with more arriving all the time. More than 29,000 satellites, pieces of rockets and other bits of debris large enough to track from the ground are circling the planet. Smaller items number in the millions. The Californian company SpaceX alone has launched some 1,700 satellites over the past 2 years as part of its Starlink network, which provides broadband Internet, with thousands more planned. Other companies are also planning such megaconstellations, and more and more nations are launching or plan to launch satellites.
This growing congestion is drastically increasing the risk of collisions in space. At the European Space Agency’s operations centre in Darmstadt, Germany, which controls key research spacecraft, hundreds of e-mail alerts arrive each day warning of potential space smash-ups. And, in May, NASA engineers spotted a 5-millimetre-wide hole in one of the International Space Station’s robotic arms, created by a collision with an unknown piece of space junk.
These close calls highlight not only the need to be more thoughtful about what we put into space, but also that it’s well past time the global space community developed a sustainable framework for managing space traffic. Such a move would benefit both the scientists who rely on observations from orbit and humanity as a whole, because satellites are crucial for modern communication and navigation.