Part I: Multiple Choice Questions. There are 30 multiple choice questions worth 2 points each. Choose the best answer and record it on the scan sheet. 1. Main sequence stars obey a relation between A. age and spectral type. B. composition and surface temperature. C. mass and luminosity. D. none of these. 2. The Hertzsprung-Russell (H-R) diagram is a plot of stellar A. temperature vs. mass. B. mass vs. age. C. luminosity vs. temperature. D. spectral type vs. color. 3. Why are the terrestrial planets so much smaller than the Jovian ones? A. They spin so fast they flung off most of their original matter which has ended up in the comet cloud. B. Near the Sun, only hard to melt substances which are rare compared to hydrogen could condense. Thus, there was less material to build them. C. They are formed from highly compressible material such as hydrogen and helium so they could be squeezed to a very small size. D. The Sun has pulled material off of them. 4. The Hubble Space Telescope (HST) is more powerful than ground-based telescopes for many astronomical studies because A. its images are not blurred by the earth's atmosphere B. it uses electronic detectors, not photographic film C. it has a larger mirror than any ground-based telescope D. it can go close to the stars 5. An optical spectrum of a star it would be a(n) _______ spectrum. A. absorption B. filtergram C. emission D. continuous 6. The mass of a main-sequence star determines all of the following properties EXCEPT A. luminosity. B. lifetime. C. composition. D. radius. 7. What is the primary energy transport mechanism in stars? A. A combination of radiation and convection. B. A combination of convection and conduction. C. Convection. D. Radiation. 8. The main sequence is primarily a sequence in stellar A. composition. B. mass. C. size. D. age. 9. Which statement below concerning the Jovian planets is INCORRECT? A. The Jovian planets have more satellites than the terrestrial planets. B. The Jovian planets are composed primarily of hydrogen and helium. C. All the Jovian planets have rings encircling them. D. The Jovian planets have shorter orbital periods than terrestrial planets. 10. As the solar nebula collapsed, A. the amount of angular momentum remained the same. B. the bulk of the gas ended up in the Sun. C. it gradually flattened to a disk-shaped cloud. D. all of the other answers. 11. The map of solar system in order of distance from the sun would read A. jovian planets, asteroid belt, terrestrial planets, Kuiper belt. B. terrestrial planets, asteroid belt, jovian planets, Kuiper belt. C. terrestrial planets, asteroid belt, Kuiper belt, jovian planets. D. terrestrial planets, jovian planets, asteroid belt, Kuiper belt. 12. Wien's law relates A. an object's speed to its mass. B. the shape of an orbit to its distance from the Sun. C. the wavelength of light to its velocity. D. the color of radiation to the temperature of the body emitting it. 13. Most of the stars in our galaxy (about 90%) are now on the main sequence in the HR diagram. That is because A. it is the longest lived phase of life for most stars. B. red giants only form from the relatively rare highly massive stars. C. there are no old stars in our galaxy. D. it is the only stable configuration for a star. 14. Fusion reactions can occur in A. stars with masses exceeding 8% of the sun's mass. B. Jupiter mass exoplanets. C. brown dwarfs. D. test tube mixtures of palladium and heavy water. 15. Comets differ from asteroids in that A. they do not have cratered surfaces. B. they have low densities. C. there are not many of them. D. they are composed of ice as well as rock. 16. Stars twinkle more than planets because A. of an optical illusion that makes all dim light sources flicker. B. refraction of light by irregularities in our atmosphere affects small sources more than large ones. C. starlight scatters differently from atmospheric dust particles than light from planets. D. the light output from stars are intrinsically more variable than from planets. 17. The composition of solid objects in the outer solar system differs from those inside the frost line in that A. they are composed of rock. B. they are composed of ices as well as rocks and metals. C. they are composed of ices instead of rock. D. there is no difference. 18. Which of the following is NOT one of Kirchoff's Laws? A. Hot, dense objects emit a continuous spectrum. B. Hot, diffuse gas produces an emission line spectrum. C. The peak wavelength of light emitted by a thermal source decreases with increasing temperature. D. A cool medium obscuring a continuum source results in an absorption line spectrum. 19. Close up images of asteroids obtained by space probes show that asteroids have A. spherical shapes. B. volcanic activity. C. cratered surfaces. D. atmospheres. 20. Globular clusters are A. diffuse stellar systems held together by unseen dark matter. B. loose associations of young stars. C. gravitationally bound aggregates of millions of stars. D. dark patches ("globules") of dust in interstellar space. 21. Electromagnetic radiation can be described A. only as a particle. B. only as a wave. C. both as a wave and as a particle. D. only as what our eyes can see. 22. As a star like the Sun evolves into a red giant, its core A. contracts and heats. B. contracts and cools. C. expands and cools. D. expands and heats. 23. If all the asteroids in the asteroid belt were assembled into a planet, it would have a mass A. Much greater than Jupiter's mass. B. Much less than that of the Earth. C. About the same mass as the Earth. D. About the same mass as Jupiter. 24. Which of the following types of observations must be done above the Earth's atmosphere? A. All of these can be done on the earth. B. X-ray C. Radio D. Optical 25. Which of the following main-sequence stars would have the highest surface temperature? A. G2 B. B5 C. M1 D. A0 26. In order from the hottest to the coolest stars, the order of the stellar spectral sequence is A. OBAFGKM B. ABFGKMO C. MKGFABO D. OBFGAMK 27. What is a star's source of energy during its main-sequence phase? A. Gravitational contraction B. Convection C. Uranium fission D. Hydrogen fusion 28. The two main reasons we use large telescopes for observations in astronomy are: A. Magnification and resolution. B. Magnfication and optical quality. C. Light gathering power and resolution. D. Magnification and clarity. 29. What is the energy source of brown dwarfs? A. Convection B. Gravitational contraction C. Hydrogen fusion D. Uranium fission 30. In order to begin nuclear fusion, a high temperature is required in the center of a star to overcome the A. gravitational force between particles. B. nuclear force between neutrons. C. electrical repulsion between protons. D. nuclear force between protons. 31. (Extra credit) Jupiter has been near opposition for much of the semester. Does this mean it has been moving A. prograde, or B. retrograde? 1. C. 2. C. 3. B. 4. A. 5. A. 6. C. 7. A. 8. B. 9. D. 10. D. 11. B. 12. D. 13. A. 14. A. 15. D. 16. B. 17. B. 18. C. 19. C. 20. C. 21. C. 22. A. 23. B. 24. B. 25. B. 26. A. 27. D. 28. C. 29. B. 30. C. 31. B.