Astronomy 100, Exam #4 BName____________________________________ ID #__________________________No notes, No books; You can use calculatorsThe letter at the top of the test needs to correspond to letter at top of the answer sheet.Constants that you may need to know:•c = 3 x 108 m/s•G = 6.67 x 10-11 m3/(kg-s2)•h = 6.626 x 10-34 J-s•g = 9.8 m/s2•σ = 5.7 x 10-8 W/(m2-K4)•Solar Luminosity = 3.8 x 1026 W•1 parsec = 3.26 light years•Hubble’s constant = 71 km/s/Megaparsec•1 Megaparsec = one million parsecs 1) The Drake equation is a simple way of trying to calculate …A) The age of the universeB) The dimensions of the universe C) The number of civilizations that are capable of interstellar communication that are currently existing in our galaxy D) how much longer life will exist on EarthE) The probability a supernova will explode near Earth and cause life to become extinct2) What type of galaxy is the galaxy we reside in?A) LenticularB) SpiralC) Irregular D) EllipticalE) Dwarf elliptical3) The reciprocal of Hubble’s constant (1/Hubble’s constant) gives an estimate of the____________ the universe. A) size right after the Big Bang ofB) critical density of C) time before civilizations arose inD) number of Galaxies inAstronomy 100, Exam #4 BE) age ofAstronomy 100, Exam #4 B4) The two most abundant elements in our Galaxy are? A) oxygen and carbon. B) hydrogen and helium. C) iron and hydrogen. D) carbon and iron. E) iron and helium.5) The two most abundant elements in the Universe are? A) oxygen and carbon. B) iron and hydrogen. C) hydrogen and helium. D) carbon and iron. E) iron and helium.6) What is ALH 84001 (Allan Hills 84001)?a. Largest supernova every recordedb. Brightest quasar in the skyc. Meteorite from Mars that was thought to contain evidence for life on Marsd. Closest galaxy to our galaxye. The black hole at the center of our galaxy7) Why are Cepheid Variables important for determining astronomical distances?A) Cepheid Variables are all at approximately the same distance from Earth B) All Cepheid Variables have approximately the same apparent brightness C) The period of their variability is proportional to their luminosityD) All Cepheid Variables have approximately the same luminosityE) Their age is proportional to their distance from the center of our galaxy.Astronomy 100, Exam #4 B8) What is produced when a proton and an antiproton come into contact? A) 2 neutronsB) 2 photonsC) 2 quarksD) 2 neutrinos E) 2 electrons9) Based on our current understanding of physics, it would seem that we can understandthe conditions that prevailed in the early universe as far back in time as ______.A) 3 minutes after the Big Bang.B) 380,000 years after the Big Bang. C) 10-89 seconds after the Big BangD) 10-3 seconds after the Big BangE) 10-43 seconds after the Big Bang10) What is the main way that we determine the mass distribution of a spiral galaxy? A) Counting the number of stars we can see at different distances from the galaxy's center. B) Measuring its mass-to-light ratio. C) Constructing its rotation curveD) Measuring the frequency of supernovasE) Determining the luminosity of O and B stars in the disk 11) What galaxy do we reside in?F) Small Magellanic CloudG) Milky WayH) WhirlpoolI) Cartwheel J) AndromedaAstronomy 100, Exam #4 B12) A standard candle is ______. A) another name for a barred-spiral galaxy. B) another name for a main-sequence star. C) a black hole that emits light at a specific wavelengthD) another name for a pulsar E) a light source of known luminosity.13) What does Hubble's law tell us? A) The larger the mass of a star, the more light it emits. B) The more distant a galaxy, the faster it is moving away from us. C) The faster a spiral galaxy's rotation speed, the more luminous it is. D) The number of stars in a cluster is proportional to its apparent brightnessE) The number of supernovas in a galaxy is proportional to the mass of that galaxy 14) Current estimates of the age of the universe is that the universe is about___________ old. A) 14 million years B) 140 billion years C) 140 million years D) 1.4 billion yearsE) 14 billion yearsAstronomy 100, Exam #4 B15) Which of the following best summarizes what is meant by dark matter?A) Matter that we have identified from its gravitational effects but that we cannot see from Earth in any wavelength of light.B) Matter that is only apparent from Earth in radio wavelengthsC) Matter that is only apparent from Earth in ultraviolet wavelengthsD) Matter that only gives off neutrinosE) Matter that only gives off positrons16) What is the Tully-Fisher Relation? A) The larger the mass of a star, the more light it emits B) The more distant a galaxy, the faster it is moving away from us. C) The faster a spiral galaxy's rotation speed, the more luminous it is. D) The number of stars in a cluster is proportional to its apparent brightnessE) The number of supernovas in a galaxy is proportional to the mass of that galaxy 17) Which galaxy may collide with our galaxy in approximately 5 billion years?A) Pegasus Dwarf GalaxyB) Lost GalaxyC) Cartwheel GalaxyD) Sombrero GalaxyE) Andromeda Galaxy 18) A galaxy is moving away from us at a speed of 7,100 km/s. How far is this galaxy away from us? A) 10 MegaparsecsB) 100 MegaparsecsC) 1,000 MegaparsecsD) 10,000 MegaparsecsE) 100,0000 MegaparsecsAstronomy 100, Exam #4 B19) Who claimed to see canals on the surface of Mars?A) Fritz ZwickyB) Albert EinsteinC) Edwin HubbleD) Jocelyn BellE) Percival Lowell20) What is SETI short for? A) supernovas that explode at specific time intervalsB) search for the equation that predicts the universe’s increase in diameterC) stars emit light in the infraredD) seasonal expansion in the thermal infraredE) search for extraterrestrial intelligence21) Which of these is the least important factor in determining the number of civilizations capable of interstellar communication that are currently residing in our galaxy?A) the number