1. Ch.20 The Solar System Section 3: The Inner Planets

2. Section 3 Earth – The four inner planets are small and dense and have rocky surfaces – Terrestrial planets: meaning “Earth” – Water Earth is unique in our solar system in having liquid water at its surface – Atmosphere

3. Section 3 Mercury – Mercury The smallest terrestrial planet and the planet closest to the sun – Exploring Mercury – Mercury’s Atmosphere

4. Section 3 Venus – Venus’s density and internal structure are similar to Earth’s. But, in the other ways, Venus and Earth are very difficult – Venus’s Atmosphere Greenhouse effect – Exploring Venus

5. Section 3 Mars – Mars’s Atmosphere – Water on Mars Scientists think that a large amount of liquid water flowed on Mars’s surface in the distant past – Seasons on Mars – Exploring Mars