The Detection and Properties of Planetary Systems Prof. Dr. Artie Hatzes

1. The Detection and Properties of Planetary Systems Prof. Dr. Artie Hatzes

2. Artie Hatzes Tel:036427-863-51 Email: artie@tls-tautenburg.de www.tls-tautenburg.de→Lehre→Vorlesungen→Jena

3. The Detection and Properties of Planetary Systems: Wed. 14-16 h Hörsaal 2, Physik, Helmholz 5 Prof. Dr. Artie Hatzes The Formation and Evolution of Planetary Systems: Thurs. 14-16 h Hörsaal 2, Physik, Helmholz 5 Prof. Dr. Alexander Krivov Exercises Wed. 12-14 and Thurs. 16-18 h Seminarraum AIU, Schillergässchen 2 Dr. Torsten Löhne

4. Detection and Properties of Planetary Systems 15. April Introduction 22. April The Doppler Method 29. April Results from Doppler Surveys I. 29. April Results from Doppler Surveys II 06. May The Transit Method from the Ground 13. May The Transit Method from Space: Kepler and CoRoT 13. May The Characterization of Planets 20. May CoRoT-7: The first transiting terrestrial planet 27. May Astrometry 27. May Microlensing 03. June Terrestrial Planets in the Habitable Zone 10. June Future Space Missions or Direct Imaging 17. June Guest (TBD) 24. June Guest (TBD) Preliminary Program, subject to change, particularly on „double“ lectures

5. Literature Planet Quest, Ken Croswell (popular) Extrasolar Planets, Stuart Clark (popular) Extasolar Planets, eds. P. Cassen. T. Guillot, A. Quirrenbach (advanced) Planetary Systems: Formation, Evolution, and Detection, F. Burke, J. Rahe, and E. Roettger (eds) (1992: Pre-51 Peg)

6. Introduction Outline • Early Models of the Solar System • Geocentric • Heliocentric • Tour of Our Solar System • Extrasolar Planets • Our expectations • How do we find them?

7. The Geocentric Solar System

8. The Geocentric Solar System: Eudoxus Eudoxus of Cnidus (410 -355 B.C.) developed the two sphere model, a spherical Earth and a spherical heavenly realm. Each planet had its own concentric sphere that rotated at a different rate. Problem: Could not predict planet motions

9. Apollonius of Perga (262-190 B.C.): Epicycles To account for the true motion of planets and to explain retrograde motion Apollonius introduced epicyles This could also explain the changing brightness of planets

10. Claudius Ptolemy (90-168 AD): The Ptolemaic System In the Almagest he extended the concepts of the ancient Greeks and Babylonians The Ptolemaic System dominated astronomical thought until well into the Renaissance

11. Capellan Geocentic Model • Martianus Capella (5th century) • Paul Wittich (1546-1586) In the Capellan model Mercury and Venus orbit the Sun, but the Sun and outer planets orbit the stationary Earth

12. Tycho Brahe (1546-1601): The Tychonic Model Proposed a more radical form of the Capellan system where all the other planets orbit the sun, but the sun orbits the stationary earth. Reason: if the earth moved one should observer stellar parallax, which he did not. In a sense, this combined the Copernican and Ptolemaic systems

13. The Heliocentric Solar System

14. Aristarchus (310 – 230 B.C.) • Believed that stars were infinitely far away and thus would show no parallax • Determined the diameter of the moon was about 4400 km (actual 3500 km) • Estimated the distance and size of the Sun (incorrectly, but due to poor data) • Proposed Heliocentric Model of the solar system

15. Copernicus (1473-1543) First proposed a modern version of the heliocentric model. He published this just before his death. Given the hostility of the church, this was probably a good idea!

16. Because Copernicus only used circular orbits he could not reproduce the motion of the planets • The Tychonic (Ptolemaic) System could because it had more degrees of freedom. • Purely on the basis of reproducing the observations one would have to choose the Tychonic System over the Copernican system

17. Support for the Copernican Model: Galileo (1564-1642) Note: phases of Venus still compatible with Capellan model Galileo observed the phases of Venus which showed the full set of phases. According to the Ptolemaic system, only crescent phases could be observed. Strong support of the geocentric model, but what about planet motion?

18. Kepler (1571-1630): Orbits Explained Kepler was an assistant to Tycho and used his observations to devise his three laws that could explain all the orbital motions of the planets.

19. The orbit of every planet is an ellipse and the sun is at one focus

20. 2. A line joining the planet and the sun sweeps out equal areas during equal intervals of time (conservation of angular momentum)

21. 3. P2 = a3

22. Retrograde Motion Explained

23. Our Solar System Today

24. A quick tour of our solar system A good source for this is: www.nineplanets.org and solarsystem.nasa.gov

25. Mercury Distance: 0.38 AU Period: 0.23 years Radius: 0.38 RE Mass: 0.055 ME Density 5.43 gm/cm3 (second densest) Satellites: None Structure: Iron Core (~1900 km), silicate mantle (~500 km) Temperature: 90K – 700 K Magnetic Field: 1% Earth Atmosphere: Thin, bombarded by Solar Wind and constantly replenished

27. Venus Distance: 0.72 AU Period: 0.61 years Radius: 0.94 RE Mass: 0.82 ME Density 5.4 gm/cm3 Satellites: None (1672 Cassini reported a companion) Structure: Similar to Earth Iron Core (~3000 km), rocky mantle Temperature: 400 – 700 K (Greenhouse effect) Magnetic Field: None (due to slow rotation) Atmosphere: Mostly Carbon Dioxide

28. Pancake volcanoes Magellan Radar Imaging Sif Mons

29. Earth Distance: 1.0 AU (1.5 ×1013 cm) Period: 1 year Radius: 1 RE (6378 km) Mass: 1 ME (5.97 ×1027 gm) Density 5.50 gm/cm3 (densest) Satellites: Moon (Sodium atmosphere) Structure: Iron/Nickel Core (~5000 km), rocky mantle Temperature: -85 to 58 C (mild Greenhouse effect) Magnetic Field: Modest Atmosphere: 77% Nitrogen, 21 % Oxygen , CO2, water

31. Mars Distance: 1.5 AU Period: 1.87 years Radius: 0.53 RE Mass: 0.11 ME Density: 4.0 gm/cm3 Satellites: Phobos and Deimos Structure: Dense Core (~1700 km), rocky mantle, thin crust Temperature: -87 to -5 C Magnetic Field: Weak and variable (some parts strong) Atmosphere: 95% CO2, 3% Nitrogen, argon, traces of oxygen

33. Phobos Deimos Are believed To be captured asteroids

34. Jupiter Distance: 5.2 AU Period: 11.9 years Diameter: 11.2 RE (equatorial) Mass: 318 ME Density 1.24 gm/cm3 Satellites: > 20 Structure: Rocky Core of 10-13 ME, surrounded by liquid metallic hydrogen Temperature: -148 C Magnetic Field: Huge Atmosphere: 90% Hydrogen, 10% Helium

36. The Oscillating Brown Oval (Hatzes et al. 1981)

37. Saturn Distance: 9.54 AU Period: 29.47 years Radius: 9.45 RE (equatorial) = 0.84 RJ Mass: 95 ME (0.3 MJ) Density 0.62 gm/cm3 (least dense) Satellites: > 20 Structure: Similar to Jupiter Temperature: -178 C Magnetic Field: Large Atmosphere: 75% Hydrogen, 25% Helium

39. Uranus Distance: 19.2 AU Period: 84 years Radius: 4.0 RE (equatorial) = 0.36 RJ Mass: 14.5 ME (0.05 MJ) Density: 1.25 gm/cm3 Satellites: > 20 Structure: Rocky Core, Similar to Jupiter but without metallic hydrogen Temperature: -216 C Magnetic Field: Large and decentered Atmosphere: 85% Hydrogen, 13% Helium, 2% Methane

40. HST Image Voyager

41. Neptune Distance: 30.06 AU Period: 164 years Radius: 3.88 RE (equatorial) = 0.35 RJ Mass: 17 ME (0.05 MJ) Density: 1.6 gm/cm3 (second densest) Satellites: 7 Structure: Rocky Core, no metallic Hydrogen (like Uranus) Temperature: -214 C Magnetic Field: Large Atmosphere: Hydrogen and Helium

43. 2006 IAU Definition of a Planet • is in orbit around the Sun, • has sufficient mass to assume hydrostatic equlibrium (a nearly round shape), and • has „cleared the neighborhood" around its orbit. If a non-satellite body fulfills the first two criteria it is termed a „dwarf planet“. Originally, the IAU wanted to consider all dwarf planets as planets. Under the new definition Pluto is no longer a planet, but rather a dwarf planet.

44. 9

45. Pluto before 2006 Pluto at the IAU 2006 Pluto today

46. Completing the Census: Satellites 8

47. Europa

48. Titan

49. Io

50. Triton