1. 8 Exoplanets Worlds Without End Copyright Lynette Cook, used with permission

2. 8 Goals Are there planets around other stars? How do we know? Are they systems like ours? Copyright Lynette Cook, used with permission

3. 8 Copyright – Tyler Nordgren Are there other Earths?

4. 8 Putting it all together Copyright Lynette Cook, used with permission

5. 8 1. Thermal Emission and Spectral lines A star like our Sun has absorption lines. HOT COOL You

6. 8 2. Reflex Motion The Moon doesn’t orbit the Earth. The Earth doesn’t orbit the Sun. What do they do? They each orbit their combined center of mass. X

7. 8 Wobble

8. 8 3. Doppler Shifts Movement towards or away yields Doppler shifts. http://www.howstuffworks.com/planet-hunting2.htm You X

9. 8 4. Doppler Velocity From Doppler shifts we get a velocity and period.

10. 8 5. Kepler Kepler’s Second Law: Kepler’s Third Law:

11. 8 Result: 51 Pegasi Mayor and Queloz a = 0.052 AU Copyright Lynette Cook, used with permission

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14. 8 Worlds without End? Known Planets: –In our Solar System: 9 –Outside our Solar System: 133 Known Planetary Systems: –Prior Sept. 1995: 1 (ours) –As of Sept. 2004: 14 Copyright Lynette Cook, used with permission

15. 8 Upsilon Andromedae

16. 8 But Are They Real? Copyright Lynette Cook, used with permission

17. 8 Planet Shadows

18. 8 HD 209458 Based on Doppler curve, knew when planet might pass in front of its star. Greg Henry (Tennessee State Univ.)

19. 8 Copyright Lynette Cook, used with permission

20. 8 Savage et al. 2001 Hubble Space Telescope

21. 8 Hot Jupiters Atmosphere evaporation

22. 8 51 Peg