An asteroid is an extra terrestrial body made of rock or metal… or both.

They come in all sizes. Some are as small as a potato; others are like mini planets, as big as a whole country.

Most of them orbit the sun between Mars and Jupiter and form a ring called the “asteroid belt”.

Where do they come from?

The solar system was formed out of a swirl of gas, dust and ice particles.

These tiny particles joined together bit by bit to form bigger and bigger rocks, until they became planets.

Rocks that didn’t manage to stick together are called asteroids, which means “starlike”.

We know there are thousands of them. The brightest, Vesta, is sometimes visible with the naked eye. To see others, you need a telescope.

Probes have even been sent into space to study them close-up to find out their origins.

When asteroids collide, pieces of rock fly into space, and sometimes land on Earth.

Most of them burn up as they cross our atmosphere. They are shooting stars.

The bits that don’t burn… smash into the ground: we call them “meteorites”.

These are the only extraterrestrial rocks that scientists can really observe to learn more about how the solar system was formed. Precious stones!