1. The Inner planets
Section 28.2

2. Main idea
Mercury, Venus, and Earth, and Mars have high densities and rocky surfaces
This is why we call them the terrestrial planets

3. mercury Closest to the Sun making it difficult to see from Earth
1/3 the size of Earth
Has no moons
Atmosphere is replenished by the Sun
Atmosphere composed of oxygen and sodium
Surface covered with craters and plains

4. Scarps: planetwide system of cliffs

6. Venus 2nd closest to the Sun Has no moons
The brightest planet in the sky
Often called the evening star

7. Rotates very slowly
1 day on Venus = 243 Earth days
Venus rotates clockwise (opposite to most)
Very similar to Earth in diameter, mass, and density
Clouds on Venus consist of sulfuric acid
Greenhouse effect causes the high concentration carbon dioxide in the atmosphere to keep Venus’ surface temperature hot enough to melt lead.
Venus is the hottest planet

8. Earth

9. It’s distance from the Sun and nearly circular orbit are perfect for life which allow water to exist in all three states
It’s mild greenhouse effect and moderately dense atmosphere of Nitrogen and Oxygen are also perfect conditions for life
Most tectonically active terrestrial planet
Has one moon

10. Mars Called the ‘red planet’ because of its reddish surface
Smaller than Earth and less dense
Has two moons: Phobos and Deimos
Thin atmosphere
Constant wind and dust storms

11. Surface Northern hemisphere: cratered plains
Southern hemisphere: cratered highlands
Four gigantic volcanoes near equator
Largest: Olympus Mons
Ice caps on both poles

12. Tectonics Valles Marineris: 10 times the length of the Grand Canyon
There is currently NO plate movement. The volcanoes and canyons were caused by hot spots of volcanic activity
Erosion patterns suggest that water once existed on Mars

13. Mars curiosity