Space junk

Space junk is a major problem. It can collide with satellites and disable them, as happened to the French Cerise spacecraft in 1996.

Some of the debris is very large, such as burnt-out rocket stages and dead spacecraft. However, most of it is much smaller.

Today, telescopes and radar are monitoring 8500 pieces of junk down to 10 cm in size. Many millions of pieces are even smaller, including flecks of paint and dust.

Normally, these would not be a threat, but in space, debris travels at high speed. Even dust particles act like tiny bullets.

Pieces more than 10 cm across can disable or destroy a spacecraft or threaten a spacewalking astronaut.

The European Space Operations Centre (ESOC) watches this debris very closely. It uses a 1 metre telescope in the Canary Islands and a radar system based in Germany. ESA’s Proba satellite also monitors microscopic debris.

This information allows ESOC to give advice about when a spacecraft should be moved to a safer orbit. It also provides early warning of large objects that are about to re-enter the atmosphere.