A broken satellite might sound harmless. After all, it is hundreds of kilometres above our heads.
Imagine a motorway on which every abandoned car keeps moving at thousands of kilometres an hour. Nobody can stop them, and every crash scatters dangerous fragments across more lanes. It is an imperfect image, but it captures a growing risk above Earth: orbital debris.
Space junk includes satellites that no longer work, spent rocket bodies and fragments from explosions or collisions. Unlike litter on a beach, this debris travels at orbital speeds. NASA notes that even very small impacts can seriously damage spacecraft. The danger matters on Earth too: operational satellites provide communication, navigation, Earth observation and weather information.
The European Space Agency's September 2026 report shows how quickly orbital traffic is expanding. In 2025, over 300 launches delivered more than 4,000 new payloads. These were mostly intended for productive use, not immediate disposal. Yet every launch brings responsibility for what happens when equipment fails or reaches the end of its mission.
The issue is not limited to visible wreckage. Some debris is too small to track reliably, while larger fragments can force satellite operators to plan evasive manoeuvres. A collision may generate thousands of pieces, increasing the chance of further collisions. This is the logic behind the Kessler syndrome: a self-reinforcing chain reaction that could eventually make some orbital regions difficult to use.
There is no single solution. Satellites can be designed to re-enter the atmosphere safely after their missions. Rocket stages can be emptied of remaining fuel and energy to reduce the risk of explosions. Better tracking and coordination can help active spacecraft avoid danger. Engineers are also investigating robotic ways to remove large abandoned objects, although such missions are complicated and costly.
The deeper question is political and ethical. Who owns abandoned equipment in orbit, and who has permission to touch it? Should launch licences require companies to pay for future disposal? Space may seem limitless when we look at the stars, but the useful orbital highways around Earth are not. Perhaps the biggest challenge is persuading today's users to protect a shared resource for tomorrow's explorers.
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