Meteoroids are rocks still in space, and vary in size from grains of dust to small asteroids.

Meteors are meteoroids that enter Earth's atmosphere.

They enter at high speed and burn up. The fireballs are nicknamed shooting stars.

And meteorites are meteoroids that survive their journey through the atmosphere and hits the ground.

Nasa said an estimated 48.5 tons of meteoritic material falls on Earth each day - almost all of it burns up in the atmosphere.