1. Our Solar System

2. Objectives Essential Question Objectives
What would life be like on another planet?
Objectives
Describe conditions on other planets in our solar system
Explain why the planets have different conditions (Inner vs. Outer)

3. Retrograde Motion Retrograde motion
A planet’s apparent backward motion in the sky
Similar to passing a slower car

4. Measuring Distance in Space
Astronomical Unit (AU)
A planets average distance to the Sun
Sun to Earth = 1 AU = 1.496x108 km

5. Kepler’s First Law
Perihelion – When a planet is closest to the sun in its orbit
Aphelion – When a planet is farthest away from the sun in its orbit
Eccentricity – The shape of a planets elliptical orbit

6. Terrestrial Planets
Inner Planets

7. Mercury
No Moons
1/3 size of Earth
Mercury has essentially NO atmosphere

8. Surface covered with craters and plains Nickel Iron core
Mercury
Temp ranges from 700 K to 100 K
Due to slow rotation and proximity to the sun
Surface covered with craters and plains
Nickel Iron core
Molten Zone in the interior

9. Venus No Moons Average temp: 737 K (Runaway Greenhouse Effect)
Almost 90 times greater pressure
Retrograde Rotation

10. Venus
Atmosphere has Carbon Dioxide and Nitrogen
Surface smoothed by volcanic lava flows, few impact craters
Interior similar to Earths

11. Earth
One Moon
Water on Surface
Atmosphere 78% N and 21% O

12. Mars
Two Moons
Thin Atmosphere with constant wind

13. Mars Southern Mars is heavily cratered and high lands
Northern Mars dominated by plains with few craters
4 Shield Volcanoes – Olympus Mons
Large because there are no moving tectonic plates
Polar Ice caps – dry ice over water ice
Interior – Solid Nickel Iron Core

14. Gas Giant Planets
Outer Planets

15. Jupiter Eleven times larger than Earth Atmosphere contains H and He
Great Red Spot – Atmospheric Storm that has been rotating for more than 300 years.

16. Jupiter
Four Galilean (Satellites)Moons: Io, Europa, Ganymede, Callisto
Moons are composed of Ice and Rock mixtures
Jupiter has a Ring

17. Saturn
Atmosphere composed of Hydrogen, Helium and Ammonia Ice near top of clouds

18. Saturn
Rings composed of pieces of rock and ice (Range in size from microscopic to the size of a house)
Seven Major rings made up of narrower rings
Gravity of Saturn keeps the rings from coming together to form a moon
18 Satellites, largest is Titan

19. Uranus
Atmosphere contains Hydrogen, Helium and Methane Gas
Methane gives planet its bluish color

20. Rotational Axis is tipped 18 Moon and 10 rings
Uranus
Rotational Axis is tipped
Possibly caused by a collision
18 Moon and 10 rings
Rings are dark in color and hard to see
Temperature avg C

21. Neptune Atmosphere contains Hydrogen, Helium and Methane Has clouds
Great Dark Spot – Storm disappeared in 1994

22. Eight moons – Largest Triton
Neptune
Eight moons – Largest Triton
Triton has a retrograde orbit
Neptune has 6 rings composed of microscopic dust particles

23. Pluto Has a solid Surface
Not a Terrestrial Planet or a Gas Giant Planet
Half Ice and Half Rock
Pluto has a Moon – Charon
Past Kuiper Belt
Status recently changed – No longer a planet : (