Astronomy 1504/1514 Section 10 FINAL EXAM, Version 1 December 17, 2002

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1 Astronomy 1504/1514 Section 10 FINAL EXAM, Version 1 December 17, 2002 Choose the answer that best completes the question. Read each problem carefully and read through all the answers. Take your time. If a question is unclear, ask for clarification during the exam. Mark your answers on the scantron sheet and on your copy of the exam. Keep your copy of the exam and check your grade with the posted answers and the grade posted on WebCT. In order for corrections to be made before your transcript comes out on Dec 27 you MUST ask for corrections BEFORE the University shuts down on Dec 20, 2002! I will of course entertain reasonable requests for corrections for the first few weeks of the spring semester. 1. The sun passes through the summer solstice on: (a) the first day of summer (b) the first day autumn (c) the last day of summer (d) the last day of winter (e) the first day of winter 2. Today, Dec 17, 2002, the moon is very near a full moon. Which is true about the phase and moonrise in Norman on Christmas day (December 25, 2002)? (a) It is just past first quarter and it rises around 12:00pm (b) It is just past third quarter and it rises around 11:30pm (c) It is a waning gibbous and it rises around 9:00pm (d) It is a waxing crescent and it rises around 1:30am 3. Which of the following is NOT a fundamental property of a black hole? (a) mass (b) electrical charge (c) temperature (d) baryon number

2 4. Hubble s law may be expressed as: (a) v = H 0 d (b) v = H 0 /d (c) v = H 0 d 2 (d) v = H 0 /d 2 (e) a very complicated formula 5. The diameter of the Galaxy is about: (a) 1 kpc (b) 2 kpc (c) 4 kpc (d) 8 kpc (e) 30 kpc 6. The distance of the sun from the center of the Galaxy is about: (a) 1 kpc (b) 2 kpc (c) 4 kpc (d) 8 kpc (e) 30 kpc 7. The Hubble constant is related to the of the universe: (a) size (b) mass (c) age (d) luminosity 8. The speed of a planet in its orbit about the sun: (a) is constant (b) rapidly decreases, due to friction (c) depends on the planet s distance from the sun (d) depends on the planet s mass 9. Ray Davis was awarded the Nobel Prize on Dec. 10, 2002 for: (a) Detecting neutrinos from the sun (b) Detecting muons from the sun (c) Detecting light from the sun (d) Detecting protons from the sun 2

3 10. Which type of star is the most massive? (a) red giants (b) main sequence O stars (c) white dwarfs (d) main sequence M stars 11. We measure the distances to nearby ( < 10 Mpc) galaxies by using: (a) Hubble s law (b) the apparent brightness of standard candles (c) parallaxes (d) the speeds of the outermost stars in them 12. At redshifts z > 0.1, redshift can be used as a measure of: (a) brightness (b) distance (c) parallaxes 13. Standard Candles of choice for doing cosmology are (a) RR Lyra stars (b) Type Ia Supernovae (c) M dwarf stars (d) Extra solar giant planets (e) Ozzie Osborne 14. In 1998, two teams of researchers using Type Ia supernovae discovered that: (a) The universe is expanding (b) The universe is decelerating (c) The universe is accelerating (d) The universe is static 15. Which of the following objects or techniques is most useful to determine the distance to the most distant objects in the Galaxy? (a) solar type stars (b) Cepheid variables (c) RR Lyrae variables (d) main sequence fitting methods (e) white dwarf stars 3

4 16. The cosmological constant was introduced by Einstein to: (a) Keep the universe from expanding (b) Make his equations stable (c) Explain Hubble s Law (d) Make his equations pleasing to the eye 17. The percentage of stars thought to be binary is per cent. (a) 10% (b) 30% (c) 50% (d) 75% (e) 95% 18. The dark energy is: (a) Required by the distance measurements using Type Ia supernovae (b) Responsible for the accelerating universe (c) Also called the cosmological constant, quintessence, or the fifth essence 19. From the Cosmological Principle it follows that: I. The universe is expanding II. The universe has no center III The universe has no edge (a) I and II (b) I and III (c) II and III (d) I, II, and III 20. The solution to Olber s paradox requires that: (a) The universe is expanding (b) The universe has no center (c) The universe has no edge (d) The universe had a beginning 21. The first person to correctly suggest a solution to Olber s paradox was: (a) Albert Einstein (b) Immanuel Kant (c) Edgar Allen Poe (d) Olber 4

5 22. The Cosmic Background Radiation: I. Was discovered by Penzias and Wilson at Bell Labs II. Was predicted by Gamow, Alpher, and Hermann III. Is nearly a perfect blackbody (a) I (b) I and II (c) I and III (d) I, II, and III 23. The fact that the universe is flat (or very nearly so) is determined from: (a) measuring the distance to Type Ia supernovae (b) measuring the cosmic background radiation (c) The cosmological principle (d) The general theory of relativity 24. In the Big Bang the following elements were produced: (a) Carbon, Nitrogen, Oxygen (b) Argon and Helium (c) Hydrogen and Helium (d) Iron 25. The Horizon Problem and the Flatness Problem are solved by: (a) The theory of inflation (b) Olber s paradox (c) dark energy (d) dark matter 26. What process is important on all terrestrial planets, regardless of whether they have an atmosphere? (a) erosion (b) storms (c) lightening (d) volcanism 27. It is thought that Jupiter played an important role in the formation of the solar system because: (a) there is life on Europa (b) gravitational slingshoting helps to clear the solar nebula (c) it kept hydrogen away from the earth 5

6 28. The age of the solar system is best determined by: (a) radioactive dating of moon rocks brought back by the Apollo astronauts (b) radioactive dating of the oldest rocks on earth (c) models of the sun (d) none of the above 29. The total number of stars which around which planets have been detected orbiting them is about: (a) one (b) two (c) five (d) ninety 30. Extra solar giant planets are discovered by: (a) actually seeing them in images (b) measuring the Doppler wobble they induce on their parent stars (c) measuring changes in the colors of the stars 31. Scientists are worried about increases in the amount of CO 2 in the earth s atmosphere due to the burning of fossil fuels because: (a) CO 2 is a greenhouse gas (b) it could lead to global warming (c) it could lead to melting of the ice in Antarctica 32. Astronomers believe that the Earth was spared a runaway greenhouse effect like that which occurs on Venus due to: (a) There was little CO 2 present in the early earth atmosphere (b) CO 2 was dissolved in the earth s oceans and turned to limestone (c) The density of Earth s atmosphere is much lower than that on Venus 33. The condensation sequence suggests that should condense farthest from the sun: (a) Terrestrial Planets (b) metals and metal oxides (c) silicates (d) ices of water, methane, and ammonia 6

7 34. The earth s moon likely formed via: (a) impact of a mars sized body with the earth (b) fission of the proto-earth (c) capture of the moon by the earth (d) the earth and moon formed together 35. Liquid water is important for life because: (a) Water expands when it freezes (b) Water has a large latent heat (c) Water has a large temperature range where it stays liquid 36. Silicon is unlikely to be the basis of extraterrestrial life because: (a) It forms far fewer compounds than carbon (b) The bond between two silicon atoms is weaker than that between two carbon atoms (c) SiH 4 (silane) has not been detected on Jupiter 37. The most likely region of the electromagnetic spectrum for communication with other civilizations is: (a) UV (b) Gamma-rays (c) the water hole (d) Optical 38. The high abundance of oxygen in Earth s current atmosphere is due to: (a) Volcanism (b) Cometary impacts (c) Photosynthesis from plants (d) all of these (e) none of these 39. Earth s original atmosphere is thought to have been: (a) highly reducing like in the Miller Urey experiment (b) moderately reducing (c) as dense as that on Venus (d) as dense as that on Mars 7

8 40. It is unlikely that habitable planets will form around M dwarf stars because: (a) They don t live long enough (b) They live too long (c) They are too hot (d) The life zone is so close that the planet s rotation period would be tidally locked to it s orbital period 41. Most short period comets probably originate in: (a) the asteroid belt (b) the Oort cloud (c) the Kuiper belt (d) none of the above 42. The sun does not now collapse because of a balance between what two forces? (a) density and temperature (b) pressure and radiation (c) temperature and radiation (d) gravity and gas pressure 43. The material in Saturn s rings could not have been primordial because: (a) the ices don t form in the same region as Saturn (b) the rings tend to spread out with time (c) no terrestrial planet has rings (d) the ices would have melted due to the heat of formation of Saturn 44. Some astronomers want to stop calling Pluto a planet because: (a) Pluto is dramatically different than its Jovian neighbors (b) Pluto is similar to a class of objects called Kuiper belt objects (c) Pluto s orbit is tilted with respect to the plane of the ecliptic (e) none of the above 45. The sun passes through the vernal equinox on the first day of: (a) summer (b) autumn (c) winter (d) spring 8

9 46. It is unlikely that habitable planets will form around O stars because: (a) They don t live long enough (b) They live too long (c) They are too hot (d) The life zone is so close that the planet s rotation period would be tidally locked to it s orbital period (e) none of the above 47. On Jupiter hydrogen is primarily in the form of: (a) di-hydrogen monoxide (b) H 2 O (c) liquid metallic hydrogen 48. One of the most important difference between the terrestrial planets and the Jovian planets is: (a) the number of moons (b) the existence of rings (c) the presence of liquid water (d) their uncompressed densities 49. The Drake Equation: (a) is an extension of Newton s laws (b) is an extension of general relativity (c) expresses the number of technological civilizations per galaxy (d) is incomprehensible to General Astronomy students 50. Which of these is not responsible to making summers hot in the northern hemisphere? (a) the length of the day (b) the height of the sun in the sky (c) the distance between the earth and the sun (d) they all play a role HAPPY HOLIDAYS -END OF TEST- 9