1. Inner Planets

2. Vocabulary
Terrestrial Planet – the four small, dense, rocky planets that orbit closest to the sun
Astronomical Unit – equals the average distance between the sun and Earth

3. Sun – Mercury – Venus – Earth - Mars
Order of Inner Planets
Sun – Mercury – Venus – Earth - Mars

4. Why do temperatures on Mercury vary so much?
Slow rotation
Close to the sun
No atmosphere

5. Why is Venus’s surface temperature so high?
Carbon dioxide in the atmosphere traps energy
Volcanoes

6. What are three factors that support life on Earth?
Water
Oxygen
Energy source

7. What makes up the surface of Mars?
Covered lava flow in the northern hemisphere
Heavily cratered in the southern hemisphere

8. Interesting Facts The largest terrestrial planet is Earth.
Venus has clouds that rain sulfuric acid on the planet.
Huge dust storms sweep across the surface of Mars.
Earth is the most geologically active of the terrestrial planets.
Mercury has the thinnest atmosphere of the terrestrial planets.

9. Rotation vs. Revolution
Rotation is one turn on its axis
Revolution is one rotation around the sun