The Solar System
Our solar system is made up of the Sun and everything that orbits it — eight planets, their moons, and countless smaller objects like asteroids.
Day and night
The Earth spins on its axis once every 24 hours. The side facing the Sun has day; the side facing away has night.
Orbiting the Sun
Earth takes one year (365 days) to orbit the Sun once. Planets closer to the Sun orbit faster and complete their year more quickly than planets further away.
Practice
Put these in order from closest to the Sun: Earth, Mars, Mercury, Venus.