ASTR1102 002 Practice Questions for Final Exam 1 The typical mass of a normal spiral galaxy is fill in the blank a 1000 solar masses b 10 9 solar masses c 1011 solar masses d 1022 solar masses 2 How many stars are in a typical normal spiral galaxy a 1000 stars b 10 9 stars c 1011 stars d 1022 stars 3 Most stars found in Elliptical galaxies are young Population I stars True or False 4 Most catalogued galaxies are classified as Irregular galaxies True or False 5 Our Milky Way Galaxy is classified as a galaxy Fill in the blank a Spiral b Elliptical c Dwarf Elliptical d S0 e Irregular 6 The Large Magellanic Cloud is classified as a galaxy Fill in the blank a Spiral b Elliptical c Dwarf Elliptical d S0 e Irregular 7 Type II supernovae are usually found in Elliptical galaxies True or False 8 What is the approximate diameter of our Milky Way Galaxy a 50 AU b 50 parsecs c 50 kpc d 50 Mpc e 50 km s Mpc 9 Compare Population I and Population II stars Specifically identify 3 characteristics that distinguish whether or not a star belongs to Pop I or Pop II 10 The stars in the disk of our Milky Way Galaxy are predominantly Population II stars True or False 11 The Sun orbits the center of our Milky Way Galaxy in an approximately circular orbit whose radius is approximately Fill in the blank a 8 AU b 8 parsecs c 8 kpc d 8 Mpc e 8 km s Mpc 12 The stars in the globular clusters of our Milky Way Galaxy are predominantly Population II stars True or False 13 The Sun is a Pop III star True or False 14 The interstellar dust in our Galaxy lies primarily in the of the Galaxy Fill in the blank a Disk b Airplane c Halo d Center e Globular Clusters 15 If you want to map out the distribution of hydrogen gas in our Galaxy what type of telescope should you use a The Hubble Space Telescope HST b The space based Infrared Spitzer Telescope c A ground based radio telescope with a receiver sensitive to 21 cm radiation d A space based X ray telescope e A ground based micro wave antenna 16 Explain why Type Ia supernovae are good standard candles to use when studying cosmology 17 What standard candle did Shapley use to measure the distances to Globular Clusters in our Galaxy a The Sun b Pop I stars c Population I Cepheid variable stars d RR Lyrae variable stars e Type Ia supernovae 18 Describe the difference between Herschel s map of our Galaxy and Shapley s map of our Galaxy Explain how and why Shapley was able to obtain a more faithful representation of the size of our Galaxy and a more faithful representation of the Sun s location in our Galaxy 19 An RR Lyrae star with an apparent magnitude m 15 has been found in a globular cluster How far away from us is this globular cluster Is this cluster in our Galaxy or well outside of our Galaxy 20 Why did Edwin Hubble use Population I Cepheid variable stars instead of Population II RR Lyrae stars to measure the distance to the Andromeda galaxy 21 An astronomer discovers a variable star in our Galaxy that has a pulsation period of 20 days Is this an RR Lyrae variable or a Cepheid variable 22 Generally speaking Pop I stars are younger than Pop II stars True or False 23 Generally speaking Pop I stars are more metal rich than Pop II stars True or False 24 Stars orbiting in the disk of the Andromeda galaxy are predominantly Pop II stars True or False 25 Generally speaking Pop I stars are younger than Pop II stars True or False 26 By carefully studying the motions of various stars near the center of our Galaxy astronomers have determined that these stars are orbiting a that is located at the center of our Galaxy Fill in the blank a Large globular cluster b Large open cluster c Massive pulsar d Supermassive black hole e Dwarf elliptical galaxy 27 The universe contains approximately 10 million galaxies True or False 28 Edwin Hubble discovered that the universe is expanding by measuring the proper motions of numerous nearby galaxies True or False 29 Edwin Hubble discovered that the universe is expanding by measuring the radial velocities of numerous nearby galaxies True or False 30 Hubble discovered that approximately half of all galaxies in our region of the universe are moving toward us and approximately half are moving away from us True or False 31 Hubble discovered that virtually all galaxies in our region of the universe are moving toward us True or False 32 Hubble discovered that virtually all galaxies in our region of the universe are moving away us True or False 33 The slope of the best fit line through the data in Hubble s velocity versus distance diagram is H0 73 km s Mpc What property of the universe is revealed by the measured slope of this line 34 A galaxy in Cluster A has a measured radial velocity of 10 000 km s while a galaxy in Cluster B has a measured radial velocity of 61 000 km s According to the Hubble Law which cluster of galaxies is farther from us 35 How were the distances determined to all of the galaxies in the so called 2dF galaxy survey See the textbook discussion associated with figure 24 24a 36 According to the Hubble Law diagram what is the approximate age of the universe a 73 km s b 73 Mpc c 13 4 billion years d 4 billion parsecs e 6000 years 37 The surface of an expanding balloon serves as a good analogy for our expanding universe if our universe Fill in the blank a Is geometrically flat b Has positive curvature c Has negative curvature 38 The surface of an expanding balloon serves as a good analogy for our expanding universe if our universe Fill in the blank a Is flat b Is open c Is closed 39 Explain what we can learn about the universe by measuring the density parameter 0 40 Explain how the discovery of Cosmic Microwave Background CMB radiation by Penzias and Wilson provided very strong support for the Big Bang theory of the origin of the universe 41 At the time of recombination in the early universe what was the radiation temperature of the universe See Figure 1 42 At the present time what is the measured radiation temperature of the universe 43 If you want to measure the present radiation temperature of the universe what type of telescope should you use a The Hubble Space Telescope HST b The space based Infrared Spitzer Telescope c A ground based radio telescope with a receiver sensitive to 21 cm radiation d A space based X ray telescope e A ground based and or space based micro wave antenna 44 What features of the present day universe developed from the very low amplitude …