The Solar System and the Earth

The Earth is one of eight planets orbiting the sun.

The Planets

From the sun outward: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The first four are rocky; the next four are gas and ice giants.

Rotation

The Earth spins on its axis once every 24 hours. This rotation causes day and night. The side facing the sun has day; the side facing away has night.

Revolution

The Earth orbits the sun once in about 365¼ days. Because its axis is tilted, different parts of the Earth receive more direct sunlight at different times of year, producing the seasons.

Practice

1. List the eight planets in order from the sun.
2. Explain the difference between rotation and revolution.
3. Why does the Earth experience seasons?

Recap

Earth rotates daily for day and night and revolves yearly for seasons, helped by its tilted axis.