1. Notes: Our Solar System

2. Distances from the Sun:
Measured in astronomical units (AU)
1 AU = 150 million kilometers (93 million mi.)
Average for Earth = 1 AU

3. Terrestrial Planets: 4 planets closest to Sun
Rocky crusts and dense mantles and cores
Crusts shaped by Tectonics, Volcanism, Weathering and Erosion, & Impact Cratering
Smaller than outer planets

4. Mercury:
Surface covered by craters (oldest surface)
No atmosphere

5. Venus: (Earth) Volcanoes and lava plains cover surface
Dense atmosphere causes high temps (470*C)
(Earth)

6. Mars:
Thin atmosphere
Temperatures range from 20*C to -90*C

7. The Gas Giants (Jovian Planets):
4 largest planets, farthest from Sun
Made of hydrogen, helium, and other gases
Extremely dense atmospheres
Have rings and many moons

8. Jupiter: Largest planet Fast winds and stormy weather
The Great Red Spot - storm larger than Earth, 100 years

9. Saturn: Large rings made of chunks of water ice
Outer ring is 3 times as wide as the planet

10. Uranus:
Axis of rotation
is almost in the
plane of its orbit

11. Neptune:
Appears a deep blue due to methane gas

12. Smaller Objects in the Solar System:
Bodies formed near the center are mostly rock and metal (asteroids, meteors)
Bodies formed far from the center are mostly ice with some rock and metal (comets, dwarf planets)

13. Solar System Formation
Began as a rotating ball of dust and gasses
Gravity caused the ball to flatten into a disk shape
Dust and gasses within the disk were merged through gravitational force to become planets and other objects

14. Stars
A large sphere of hydrogen gas hot enough for nuclear reactions to occur in its core
A star and the planets that orbit it make up a solar system