2. The Nature of Light

3. A Prism “Breaks Up” White Light When white light passes through a prism a spectrum is formed.

4. Adding a Second Prism

5. Three Types of Spectrums

7. Kirchoff-Bunsen Experiment ~ 1855

9. The Sun’s Spectrum The sun has more than 30k dark lines

10. Iron in the Sun

11. The Rosette Nebula The NGC 2363 Nebula Horsehead Nebula The reddish color seen in these pictures comes from an emission line from hydrogen

12. Young’s Double-Slit Experiment ~ 1801

14. Electromagnetic Radiation Light consists of two perpendicular waves. One wave is an electric field, the other is a magnetic field. The wave travels at a speed c, which is orthogonal to both waves.

15. Light Has Wave-Like Properties = Wavelength, measure in meters  = Period, measured in sec/cycle f = Frequency, measured in cycles/sec  = 1/ f c = f

16. Since light is a wave it must have a wavelength, denoted by. Colors and Wavelengths

17. Absorption & Emission Lines

18. Emission Lines for Various Elements Do lines exist below 400  m and above 700  m?

19. The Electromagnetic Spectrum As the wavelength increases the frequency decreases.

20. Gamma rays have the shortest Radio waves have the longest

21. Radiation and the Earth’s Atmosphere High f waves do not make it to the surface, some IR and microwaves are absorbed by water. Low f radio waves are blocked by the Earth’s ionosphere. They all must be observed from space.

24. Blackbody Radiation Curves

25. Wien’s Shift

27. Combine the Star’s Spectrum with it’s Blackbody Curve

29. How Fast Does Light Travel?

31. Why is the Sky Blue?

32. Why is the Setting/Rising Sun Red?

33. The Rutherford Experiment  -particles are shot at a thin film of gold foil. Most of the particles pass straight through foil. Some of the particles bounced back.

34. Bohr Atom

37. Hydrogen

38. The Helium Atom

39. The Origin of the Spectral Lines

40. Creation of Red and Blue Light

41. Ground State and Excited State

42. Lyman, Balmer and Paschen Series of Lines

44. Balmer Lines in a Spectrum of a Star

45. The Doppler Effect

47. Rotating and Revolving Planets

48. Star Cluster NGC 3293 in Carina T = ? UV? Visible?