1. The Planets 5/11/15 n n IN: What objects make up our solar system? 20-1 pgs. 538-548

2. The Sun n The sun is the biggest, brightest, and hottest object in the solar system. n The sun is an ordinary star. n The sun is made of hydrogen and helium.

3. Small Rocky Worlds n n Terrestrial Planets – the small, dense, rocky planets of the inner solar system.  Mercury  Venus  Earth  Mars

4. Terrestrial Planets

5. Mercury n Mercury is solid and is covered with craters. n Mercury has almost no atmosphere. n Has no moon.

6. Venus n Venus is the sixth largest planet. It’s about three-fourths the size of earth. n The surface is rocky and very hot. The atmosphere completely hides the surface and traps the heat. n Also, has no moon.

7. Earth n Earth is the fifth largest planet and the third from the sun. n Liquid covers 71 percent of the Earth’s surface. n The Earth has one moon.

8. Moon

9. Mars nMnMars is the fourth planet from the sun. nMnMars has a thin atmosphere that contains mostly carbon dioxide. nRnRed color comes from oxidation of iron. nMnMars has two small moons.

10. Moons of Mars Phobos Deimos

12. Asteroid Belt

13. Big Gaseous Worlds n n Gas Giants – the large, gaseous planets of the outer solar system.  Jupiter  Saturn  Uranus  Neptune – –All gas giants have rings!

14. Gas Giants

15. Jupiter

17. Jupiter has 67 known moons.

18. Jupiter’s Red Spot nTnThe Great Red Spot, a huge storm of swirling gas that has lasted for hundreds of years.

19. Saturn n Saturn is the second largest planet and the sixth from the sun. n In 2004 we got images of the rings.

21. Rings of Saturn n Saturn’s rings are not solid; they consist of icy particles that range in size from a few centimeters to several meters across. n The rings are very thin. Though they’re 250,000km or more in diameter, they’re less than one kilometer thick.

22. Saturn has 62 known moons.

23. Uranus n Uranus is blue-green because of the methane in its atmosphere. n Its axis is tilted 90 o.

24. Uranus has 27 known moons.

25. Neptune n Like Uranus, the methane gives Neptune its color.

26. Neptune has 13 known moons.

27. Pluto n n Pluto – doesn’t fit either category. Pluto is a small icy world clearly different from either the Terrestrial and Gas Giant worlds.

29. Dwarf Planets n Ceres – discovered on January 1, 1801, 45 years before Neptune. Considered a planet for half a century before reclassification as an asteroid. Accepted as a dwarf planet by the IAU on September 13, 2006. Ceres Neptune Ceres Neptune n Pluto – discovered on February 18, 1930. Classified as a planet for 76 years. Reclassified as a dwarf planet by the IAU on August 24, 2006. Pluto n Haumea – discovered on December 28, 2004. Accepted by the IAU as a dwarf planet on September 17, 2008. Haumea n Makemake – discovered on March 31, 2005. Accepted by the IAU as a dwarf planet on July 11, 2008. Makemake n Eris – discovered on January 5, 2005. Called the "tenth planet" in media reports. Accepted by the IAU as a dwarf planet on September 13, 2006. Eristenth planet Eristenth planet

30. Kuiper Belt

31. Oort Cloud

32. n n OUT: Summarize the difference between terrestrial planets and gas giants. Glue in the diagram