OtterKnow Kids EncyclopediaA planet is a very big, round object in space that travels around a star. Our Earth is a planet, and it travels around the Sun! Planets are round because they are so big that gravity pulls them into a ball shape.
There are eight planets in our solar system. The four planets closest to the Sun are made of rock. They are Mercury, Venus, Earth, and Mars. The four planets farther away are much bigger and made of gas and ice. They are Jupiter, Saturn, Uranus, and Neptune. Each planet is unique and special in its own way!
- To be called a planet, an object has to go around the Sun, be round, and be big enough to clear away other space stuff in its path.
- Jupiter is the biggest planet and Mercury is the smallest.
- Scientists have found thousands of planets orbiting other stars far, far away!
