Asteroids

Asteroids are small, rocky worlds that travel around the Sun. They are sometimes called minor planets. Most asteroids are lumpy and have funny shapes, not round like Earth. They come in many sizes. Some are as tiny as a pebble. Others are hundreds of miles wide. Millions of asteroids zoom through our solar system.

Where Asteroids Live

Most asteroids live in a place called the asteroid belt. The belt is a big ring between Mars and Jupiter. It has millions of rocks floating in it. But the belt is not crowded like in the movies. The rocks are very far apart. Some asteroids live in other parts of space too. A few even fly close to Earth.

What They Are Made Of

Asteroids are made of rock, metal, and dust. Some have iron and nickel inside them. Others are more like clumps of dirt and stone. Scientists think asteroids are leftover bits from when our solar system was born. That was about 4.6 billion years ago. Studying them helps us learn how the planets formed.

Fun Facts

• The biggest asteroid is named Ceres, and it is so big it is also called a dwarf planet.
• A space rock that falls to Earth is called a meteorite.
• Some asteroids have their own tiny moons that orbit around them.

Did You Know?

A huge asteroid hit Earth about 66 million years ago and helped make the dinosaurs go extinct!