Astronomy Name______________________________ Chapters 24 - 31 Period______________________________ Review Date_______________________________ ___________________________________________________________________________________ Stars Star Color and Temperature 1. Stars give off _____ wavelengths of electromagnetic radiation. 2. What is the peak wavelength of a star? 3. A star that is _____ in color is hotter than a yellow star. This means that stars with _____ have a hotter temperature. 4. Stars are referred to as _____ because they are considered nearly perfect absorbers and emitters of electromagnetic radiation. 5. In Wein's law, what happens to the peak wavelength (or color) of a star, if it's Temperature increases? 6. If Star A has a Temperature of 10,000 K and a wavelength twice that of Star B, what is Star B's Temperature? 7. What are the colors of the visible spectrum? What is the acronym associated with these colors? 8. Write the equation associated with the Stephan-Boltzmann law. What does the Stephan-Boltzmann law compare? 9. If a star's temperature doubles, how much more energy will it be giving off? Explain how you got your answer. The Bohr Model 10. What are the dark lines that appear in the continuous rainbow spectrum of the Sun called? 11. Explain the inner workings of the Bohr Model of the atom. Include a diagram in your discussion. Quantum Mechanics 12. What does quantum mechanics state? 13. What is a quanta? Give an example to aid your explanation. 14. What is the lowest energy state of an atom called? What is the ionization potential? 15. What is plasma? Atomic Spectra 16. How can we tell how much energy is absorbed or emitted by an atom? 17. Compare and contrast emission lines with absorption lines. The Hydrogen Spectrum 18. What are Hydrogen lines 19. Compare and contrast the Balmer series with the Lyman series. Spectral Types 20. List the spectral classes of stars from hottest to coolest. Write an acronym to help you remember them in order. 21. Describe how each spectral type is further broken down into divisions. 22. What specific spectral type is our Sun? Apparent Magnitude 23. What is apparent magnitude? 24. How does the apparent magnitude scale work? 25. What is the apparent magnitude of the following objects? Faintest star that can be seen with the naked eye: Sirius: Venus: Full Moon: The Sun: Absolute Magnitude 26. What is absolute magnitude? 27. What is the difference between absolute magnitude and luminosity? H-R Diagram 28. Describe what aspects of stars the H-R Diagram compares. 29. Where do most stars fall in the H-R Diagram? 30. Describe the temperature, spectral class, luminosity, and absolute magnitude of the following: Supergiant stars: Giant stars: Main Sequence Blue stars: Our Sun: Stellar Distance 31. What is parallax? 32. Explain how a parsec is determined. 33. If a star has a parallax angle of ¼ (or 0.25) arc seconds, how many parsecs is it away from the Sun? Show your work. 34. How many cm are there in one light year? in one A.U.? 35. How many light years are there in one parsec? 36. How wide is our Solar System? the Milky Way? our local cluster of galaxies? 37. How far is it in light years to the nearest star? galaxy? Stellar Motion 38. What is proper motion? 39. Name the star with the greatest proper motion and tell how fast it moves across the celestial sphere. 40. Name and describe the two components in space velocity, and tell how we to determine each. 41. How fast does the typical star move through space? Doubles, Binaries, Variables, and Clusters 42. Define: a. optical doubles b. double star / binary star c. spectroscopic binary 43. How could you recognize an eclipsing binary? 44. About what percent of all stars are members of a double star system? 45. What is a variable star? 46. Of what spectral type are Mira variables, and how big are they relative to the Sun? 47. Explain why Cepheid variables vary in luminosity. 48. What can we use Cepheid and RR Lyrae variables for? 49. Compare and contrast galactic clusters with globular clusters. 50. Where and when can the Pleiades be found? 51. Compare and contrast stellar Population I with stellar Population II. Do the stars in the galactic cluster Pleiades belong to stellar Population I or II? Energy Production in Stars 52. Stars are at enormous distances, yet we can see thousands in our night sky; they are extremely luminous!!! What is the source of their enormous energy? 53. Why does nuclear fusion produce so much energy? 54. Explain why stars favor fusion reactions over fission reactions. 55. Describe what conditions are necessary for two nuclei to fuse. 56. Briefly describe the density and processes involved in each of the layers of a star. Include a diagram of the interior of a star with labeled layers. Star Birth and Life 57. Describe the steps involved in the birth of a star. 58. At about what temperature does nuclear fusion begin? 59. What are the two forces that work against one another in a star throughout it's life? The Beginning of the End 60. List the events that occur from the time a star the size of our Sun runs out of Hydrogen in it's core to it's white dwarf stage. 61. Why doesn't a white dwarf explode? 62. What eventually happens to a white dwarf? The Fate of Massive Stars 63. Describe what happens in the core of a star that is 3 or more times the mass of our Sun from the time it becomes a red supergiant to the time fusion ceases. 64. Describe how a supernova occurs. 65. Describe what happens to a star after a supernova occurs, if it is 3 to 5 times the mass of our Sun. 66. Describe what happens to a star after a supernova occurs if it is 5 or more times the mass of our Sun. 67. Draw a diagram contrasting the life of a star 4 times greater that the size of our Sun & the life of a star 8 times greater than the mass of our Sun. Neutron Stars 68. Describe the size, shape, gravitational field, and magnetic field of a neutron star. 69. Describe what a pulsar is, and what is responsible for the "pulse". Black Holes 70. What is a black hole? Describe in detail the two types of black holes.