SOLAR SYSTEMS

1. SOLAR SYSTEMS CHAPTER 21

2. definition • Objects that revolve around a star • Major members • Planets • Moons • Minor members • Dwarf planets • Asteroids • Comets • meteoroids

3. What is a planet?(as of Aug. 2006) • The IAU said that the definition for a planet is now officially known as "a celestial body that • (a) is in orbit around a star • (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a (nearly round) shape and • (c) has cleared the neighborhood around its orbit." (not in a swarm of rocks)

4. Our solar system scoreboard • Planets= 8 • Moons= 167 • Dwarf planets= 5 • Asteroids= 536,000+ • Comets= 3,062

5. Exosolarsystems • Other solar systems • 661 new solar systems confirmed! • Over 3000 planets (exoplanets) First discovered in 1995 Estimated over 50 BILLION

6. Earth like planets(habitable zone) • Maybe 2? • Gliese D • 6x more massive than earth “superearth” • In Libra • 20 lya • HD 85512 b • In Vela • 26 lya

7. How do astronomers find new planets???????

8. Radial Velocity • Planets are detected by studying light shifts due to star wobbles • Uses Doppler Effect • Red light moves AWAY • Blue light moves TOWARDS

9. Astrometry • Measures star wobbles from geometry

10. Transit method • Planet blocks star (eclipse) • Light from star is lessen • Kepler mission

11. Optical detection • Block star’s light out using a chronograph

12. List of exoplanets • http://exoplanet.eu/catalog/

13. Exoplanet missions • Kepler- launched 2009 • Has found 77 planets so far

15. METHODS to find a new planet • http://planetquest.jpl.nasa.gov/Planet_Finder/planetfinder.html

16. Other research • LBT (large binocular telescope) • Keck telescopes (Hawaii) • Spitzer Space Telescope • Infrared telescope

17. OUR SOLAR SYSTEM

18. Our solar system

20. The planets drawn to scale

21. INNER PLANETS

22. INNER PLANETS • Terrestrial • Rocky • No rings • Smaller compared to Outer planets

23. MERCURY • No atmosphere • Temperatures fluctuate wildly • MESSANGER is currently orbiting Mercury- has completed 282 orbits (so far!)

24. Sept. 29, 2009MESSANGER

25. Messenger 9/21/11 • Mapping surface of Mercury

26. MESSANGER IMAGEAug. 23. 2012

27. VENUS • THICK atmosphere • Hot! • Crushing pressure • Rotation is retrograde • Sun rise in west; set in east

28. Pancake volcanoes

30. MARS • Thin atm. • Windy • Surface similar to Earth • Volcanoes • Old river valleys- where’s the water? • Best chance to find fossil (life?) in SS

32. Opportunity and Spirit • http://marsrovers.jpl.nasa.gov/home/

33. CURIOSITYlanded Aug. 6, 2012

34. CURIOSITY CONFIRMS WATER ONCE FLOWED!!

35. Phobos Deimos Mars Moons

37. Jovian Planets • Outer planets • Large • Many moons • all have rings • Made of gas

38. JUPITER • Often captures comets/asteroids • Shoemaker/Levy comet (1994)

39. Jupiter’s Ring systemFeb. 2007

40. Jupiter’s New Moons • Jupiter now has 63 known moons • 23 moons were discovered in 2002-3 by Earth-based telescopes http://solarsystem.nasa.gov/planets/profile.cfm?Object=Jupiter&Display=Moons

41. Saturn’s Rings • Made of Water ice and dust • Sheppard moons keep rings in place

43. Uranian Weirdness

44. A few of Uranus’s moons MIRANDA PUCK ARIEL OBERON

45. Neptune • Very active weather

46. Triton- • Liquid nitrogen volcanoes • Cantaloupe terrain • Underground oceans? • Alien life?

48. 2003 UB313 Renamed Eris (Xena) Planet ?

49. What is a planet?(as of Aug. 2006) • The IAU said that the definition for a planet is now officially known as "a celestial body that • (a) is in orbit around a star • (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a (nearly round) shape and • (c) has cleared the neighborhood around its orbit." (not in a swarm of rocks)

50. Pluto • Dwarf planet