Have you got any idea what might have damaged this piece of metal?

A bullet? A bomb blast? A car accident? No - none of those. Believe it or not, it could have been caused by this tiny speck of paint. But how on earth could something so small create so much damage?

Well, on earth, it couldn't! But in space, it could. That's because everything travelling around the earth risks being hit by a lot of rubbish called space debris.

Space debris travels between 11,000 and 35,000 miles per hour. If something travelling that fast hits something else, it does a lot of damage - no matter how small, and what the debris is made from.

Scientists use complicated machinery to demonstrate how things travelling at very high speeds cause so much damage.

It's a problem because there's loads and loads of rubbish in space. Most of it is bits of old spacecraft. Also in space are lots of satellites, which we rely on for communications - telephone calls, TV pictures and so on. If a satellite is hit, it can be badly damaged.

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NASA estimates that there are 9,000 pieces of space debris bigger than the item Fearne is holding orbiting the earth. And millions more smaller pieces too. So that's a lot of accidents, just waiting to happen.

To demonstrate how objects travelling at very high speed cause a lot of damage, a studio demonstration - the first of its kind on TV. Here's a ordinary household candle. It's very easily broken and normally won't do any damage.

And here's Steve, a special effects expert, who's going to fire the candle at the door, at a speed of around 700mph.

It's impossible to make a candle travel as fast on earth as it would in space because the air around us creates friction which slows things down.

In space there's no air, so no friction, so things go very fast. Here's the door - ready for Steven to fire the candle.

Success! Just look at the damage done to this wooden door with only a candle! Proving that something travelling very fast can cause a lot of damage.

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