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Space debris

Human-made objects in orbit that no longer serve a purpose - dead satellites, spent rocket stages, and fragments from collisions and explosions.

Why it matters

Debris matters because orbital speeds turn small objects into weapons: a centimetre-scale fragment carries the energy of a hand grenade. The concern is not any single object but the cascade - each collision creates thousands of new fragments, each capable of causing the next. The band where the problem is worst is also the band where almost everything now launches. Every operator flying there is both a contributor to the risk and exposed to it.

In our data

Debris is one of the most persistent themes in our coverage, and the reason is visible in the launch data: 144 of 350 tracked missions go to low Earth orbit, plus 47 to polar and 36 to sun-synchronous orbits, concentrating traffic into exactly the altitudes where debris already accumulates.

Where we use it

Not to be confused with

Meteoroids and other natural material, which pose a different and much smaller risk to satellites, and which no policy can reduce.