Chapter 6

1. Chapter 6 The Solar System

2. Planet Comparisons Property Terrestrial Planets Jovian Planets Distance Close Far from the Sun Size Small Large Mass Small Large Composition Rocky Solar-like Density High Low

4. Relative Sizes

5. JUPITER 3 4 5 6 7 8 9 10 11 1 2 Earths 11 Earths can fit across Jupiter’s equator.

9. Formation of the Solar System • The solar system formed from a cloud of gas and dust in a process known as accretion.

11. During the first few million years, matter in the accretion disk of our proto-sun coalesced into larger objects called planetesimals, with diameters of about 100 km.

14. Some resources compliments of Mcgraw-Hill http://www.dushkin.com/powerweb Username: astro Password: mars

15. We see evidence of accretion disk around other stars. • For example, b Pictoris.

16. Collisions of planetesimals dominated the early solar system and these objects combined to form our planets. • We see evidence of early collisions in our solar system in the form of impact craters on the planets and their moons.

18. In addition to the 9 major planets, there are at least 65 moons in our solar system. • While some of these moons are spherical, most look roughly like potatoes. • There is still minor debris left over from the formation of the solar system: asteroids and comets.

19. Bode’s Law • a simple rule that gives the distances of the planets from the Sun where N=0, 3, 6, 12, 24…for Mercury, Venus, Earth, Mars, etc.

20. Planet N Bode’s Law Radii True Orbital Radii Mercury 0 (0+4)/10 = 0.4 AU 0.39 AU Venus 3 (3+4)/10 = 0.7 AU 0.72 AU Earth 6 (6+4)/10 = 1.0 AU 1.00 AU Mars 12 (12+4)/10 = 1.6 AU 1.52 AU ____ 24 (24+4)/10 = 2.8 AU _______ Ceres 24 2.88 AU Jupiter 48 (48+4)/10 = 5.2 AU 5.2 AU Saturn 96 (96+4)/10 = 10.0 AU 9.5 AU Uranus 192 (192+4)/10 = 19.6 AU 19.2 AU Neptune ? ? 30.1 AU Pluto 384 (384+4)/10 = 38.8 AU 39.5 AU

22. What does Bode’s Law tell us? • Bode's Law predicted that there should be a planet between the orbits of Mars and Jupiter. • The "missing planet" turned out to be the asteroid belt.

23. Arizona Meteor Crater Approximately 1 mile across

24. Arizona Meteor crater superimposed over a map of NYC

25. Odessa, Texas

26. 500 ft wide

27. Exploration of the Solar System

28. Mariner Missions 1973- 1975 Exploration of Mercury and Venus

31. The Viking Lander – Mojave Desert prior to launch

32. View of the Martian Surface by Viking I

33. More recently, the Mars rover “Sojourner” analyzes a Martian rock in 1997.

34. Voyager Missions –Explore the Outer Planets

35. Photograph of Jupiter’s Red spot taken by Voyager I

36. Galileo was another probe that studied Juipiter extensively. Go To videos – Galileo flybys from JLP

37. Planets outside of our solar system have been found recently using Doppler shifts in the spectra of some stars.

39. End of Section. The End.

40. 1. Reddish color of Mars 2. Red-orange color of Jupiter's belts 3. Venus' yellowish clouds 4. Blue-green color of the surface of Uranus and Neptune 5. The yellow and orange color of Io a. ammonia clouds b. sulfur powder c. sulfuric acid clouds d. methane clouds e. iron Matching

41. 6. Has an almost featureless surface 7. The brightest planet seen from Earth 8. The most distant planet in 1996 9. Last planet in our solar system to be discovered 10. A possible fossil of single-cell life was found on a meteorite from this planet a. Sun b. Mercury c. Venus d. Earth e. Mars f. Jupiter g. Saturn h. Uranus i. Neptune j. Pluto Matching