2. Answers to all homework questions will be posted on the class website First exam: Monday, October 3.

4. If the wavelength of an electromagnetic wave increases, its velocity (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

5. If the wavelength of an electromagnetic wave increases, its velocity (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

6. If the wavelength of an electromagnetic wave increases, its frequency (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

7. If the wavelength of an electromagnetic wave increases, its frequency (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

8. If the wavelength of an electromagnetic wave increases, its energy (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

9. If the wavelength of an electromagnetic wave increases, its energy (red) Decreases (yellow) Increases (blue) Remains the same (green) Not enough information

10. You are an astronaut taking a spacewalk to fix your spacecraft with a hammer. Your lifeline breaks and the jets on your back pack are out of fuel. To return safely to your spacecraft (without the help of someone else), you should a) throw the hammer at the space ship to get someone's attention. b) throw the hammer away from the space ship. c) use a swimming motion with your arms. d) kiss your ship good bye.

11. You are an astronaut taking a spacewalk to fix your spacecraft with a hammer. Your lifeline breaks and the jets on your back pack are out of fuel. To return safely to your spacecraft (without the help of someone else), you should a) throw the hammer at the space ship to get someone's attention. b) throw the hammer away from the space ship. c) use a swimming motion with your arms. d) kiss your ship good bye.

12. The Doppler Shift: A shift in wavelength due to a wave emitter moving towards (shorter wavelength) or away (longer wavelength) from an observer.  v c =

13. The Doppler Effect 1. Light emitted from an object moving towards you will have its wavelength shortened. 2. Light emitted from an object moving away from you will have its wavelength lengthened. 3. Light emitted from an object moving perpendicular to your line-of-sight will not change its wavelength. BLUESHIFT REDSHIFT

14. Measuring Radial Velocity ● We can measure the Doppler shift of emission or absorption lines in the spectrum of an astronomical object. ● We can then calculate the velocity of the object in the direction either towards or away from Earth. (radial velocity)  v c =

15. Measuring Rotational Velocity

16. In conducting a search for life, we must understand how planets are formed and what determines their habitability.

17. What does any theory of the formation and evolution of the solar System have to account for, i.e., what are the “observed facts”?

18. The Sun: A central star Predominately H and He Most of the mass in the solar system. Rotates in same sense that planets orbit.

19. TerrestrialJovian Two “flavors” of planets

20.  Size: smalllarge  Location:closer to Sunmore distant  Composition: rocky/metallicgaseous/icy  Temperature:hotter colder  Rings:noneubiquitous  Rotation rate:slowrapid  Surface:solid not solid  Atmosphere:minimalsubstantial  Moons:few to none many Terrestrial Planets Jovian Planets

21. Planetary orbits: 1) Prograde 2) approximately coplanar 3) approximately circular Rotation: 1) Mostly Prograde 2) Includes sun 3) Includes large moons

22. There are large numbers of smaller objects in the Solar System  moons: both rocky & icy  asteroids: rocky  comets: icy

23. Craters are ubiquitous on solid objects

24. small Rocky Odd-shapes nearly circular orbits orbit planes are near Ecliptic Plane orbits in inner part of solar system Asteroids

25. The “asteroid belt”

26. small nucleus “dirty snow ball” very large tails highly eccentric orbits all orbit inclinations Comets

27. Comets are found mainly in two regions of the solar system

28. Largest Known Kuiper Belt Objects