1. Lecture 16: Searching for Habitable Planets: Remote Sensing Methods and parameters we can measure Mean density measurements: internal structure Measurements of surface temperature Atmospheric composition and temperatures Mapping of the surface

2. Star-to-planet inequalities: In light: 10 10 (optical) to 10 7 (infrared) In mass: 10 5 to 10 3 In size: 10 2 to 10.

3. HD 209458b: a Hot Jupiter

4. Methods: Mass Determination Newton’s law of universal gravitation & equality of forces: M s a s = M p a p (center of mass)

5. Mass: Radial velocities seen in star HD 209458 - the variation is due to a planet that is less massive than Jupiter. (Mazeh et al. 1999; Marcy et al. 2000)

6. More on Orbits: Angular Momentum Conservation of Angular Momentum

7. Mass: For HD 209458b: M p sin(i) = M s v s P / 2  a p = const. x ( M s / 1.1M Sun ) M jup + 0.018 + 0.1 Transit light curve helps derive the orbit inclination: i = 86 o.7 + 0.2 Both M p and R p determined to better than 5%!

8. What can we learn from transiting extrasolar planets HD 209458b: Dimming of light due to transit, observed with HST. Brown, Charbonneau, Gilliland, Noyes, Burrows (2001) Tells us DIRECTLY: Planet radius, INDIRECTLY: Planet density Planet composition

9. Mass-Radius Diagram: Hot Jupiters Super-Earths

10. Rocky & Water Planets Credit: S. Cundiff

11. Mass (Earth mass) Radius (Earth radius) Transiting Planets on the Mass-Radius Diagram 1020301 1 2 3 4 5 Earth Kepler-10b CoRoT-7b GJ1214b Earth composition 50% H 2 O 20% H/He Uranus Neptune Kepler-4b HAT-P-11b GJ436b

12. Mass [M Earth ] Radius [R Earth ] 1.00.1 10 0.5 1.0 2.0 2.5 E V M Kepler-10b Earth and Super-Earth Mass–Radius Domain Batalha et al (2011) Zeng & Sasselov (2011) 1.5 50.5 10% H/He GJ1214b CoRoT-7b Kepler-11b Kepler-11f

13. Model: Seager & Sasselov 2000 Detection: Charbonneau et al 2002

14. HD 209458b: a Hot Jupiter

15. Atmosphere: What is special about atomic Na and the alkali metals? Seager & Sasselov (2000)

16. Atmosphere: Theoretical Transmission Spectra of HD 209458 b Wavelength (nm) Occulted Area (%) Seager & Sasselov (2000)

17. Atmosphere: The tricks of transmission spectroscopy: Brown (2001)

18. A star and its planet in infrared light (Artist conception)

19. Direct Detection of Thermal Emission Infrared Eclipses of Hot Jupiters: Spitzer Space Telescope

20. First detection of light from planets orbiting other stars D. Charbonneau, & D. Deming et al. March 2005

21. Infrared Eclipses

22. Infrared Eclipses in HD 189733: Measuring the Emitted Heat Time (in fraction of day) Orbital phase Relative Intensity or Brightness Eclipse detection (Feb. 20, 2006) by Deming et al. using the Spitzer Space Telescope - in infrared light (heat)

23. Spectra Observed IR data points vs. models Knutson, Charbonneau, et al. (2007)

24. A study of an extrasolar planet Heather Knutson & Dave Charbonneau (2007)

25. A map of an extrasolar planet Heather Knutson & Dave Charbonneau (2007)

26. Main points to take home: 1) Methods and parameters we can measure 2) Mean density measurements: internal structure 3) Measurements of surface temperature 4) Atmospheric composition and temperatures 5) Mapping of the surface