BROCK UNIVERSITY. Return both the exam script and your scantron sheet when you leave the exam room.

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1 BROCK UNIVERSITY Page 1 of 18 Final Exam: April 2016 Number of pages: 18 Course: ASTR 1P02 Number of students: 952 Examination date: 19 April 2016 Time limit: 2 hours Time of Examination: 14:00 16:00 Instructor: S. D Agostino Answer all questions on the scantron sheet provided. No aids are permitted except for a non-programmable calculator. Use or possession of unauthorized materials will automatically result in the award of a zero grade for this examination. Return both the exam script and your scantron sheet when you leave the exam room. Each question is worth 1 mark. Total number of marks: The upper-left corner of the H-R diagram contains (a) hot stars that are very luminous. (b) hot stars that are NOT very luminous. (c) cool stars that are very luminous. (d) cool stars that are NOT very luminous. 2. The upper-right corner of the H-R diagram contains (a) hot stars that are very luminous. (b) hot stars that are NOT very luminous. (c) cool stars that are very luminous. (d) cool stars that are NOT very luminous. 3. The lower-left corner of the H-R diagram contains (a) hot stars that are very luminous. (b) hot stars that are NOT very luminous. (c) cool stars that are very luminous. (d) cool stars that are NOT very luminous. 4. The lower-right corner of the H-R diagram contains (a) hot stars that are very luminous. (b) hot stars that are NOT very luminous. (c) cool stars that are very luminous. (d) cool stars that are NOT very luminous.

2 ASTR 1P02 April 2016 Page 2 of If the mass of Star A is significantly greater than the mass of Star B, then (a) Star A is ridiculed far more often on TMZ. (b) the lifetime of Star A is greater than the lifetime of Star B. (c) the lifetime of Star A is less than the lifetime of Star B. (d) the two stars have the same lifetimes. 6. A cloud of gas and dust that is observable at visible wavelengths is called (a) the interstellar medium. (b) a stellar spectrum. (c) a protostar. (d) a nebula. 7. Nebulae that are bluish in colour are called (a) reflection nebulae. (b) blue nebulae. (c) emission nebulae. (d) giant molecular clouds. 8. Nebulae that are reddish in colour are called (a) reflection nebulae. (b) red nebulae. (c) emission nebulae. (d) giant molecular clouds. 9. If a clump in a giant molecular cloud is massive enough, it will begin to contract; as a result, it becomes hotter because (a) the pressure of the contraction squeezes heat out of molecules, much as dementors squeeze the souls out of their victims. (b) as it contracts, the clump gathers more light from nearby stars. (c) mini black holes evaporate in the contraction process. (d) some of the contracting clump s gravitational potential energy is converted to thermal energy. 10. As a contracting protostar heats up, if the core temperature reaches then fusion of hydrogen into helium begins and the protostar becomes a main-sequence star. (a) 10 thousand degrees K (b) 10 million degrees K (c) 10 billion degrees K (d) 10 trillion degrees K

3 ASTR 1P02 April 2016 Page 3 of The evolution of a main-sequence star is influenced primarily by (a) how often it appears on the front page of the Galactic Enquirer. (b) its core temperature. (c) its core density. (d) its core pressure. (e) its mass. 12. Stars with masses of less than about 0.08 solar masses never get hot enough to fuse hydrogen into helium, and are called (a) contestants on Dancing with the Stars. (b) white dwarfs. (c) red dwarfs. (d) brown dwarfs. (e) black dwarfs. 13. Low-mass stars, with masses less than about 0.5 solar masses, tend to be dim and cool, and are called (a) Kim Kardashian. (b) white dwarfs. (c) red dwarfs. (d) brown dwarfs. (e) black dwarfs. 14. Hydrostatic equilibrium is a balance between a star s (a) hydro force and static force. (b) hydroelectric force and magnetic force. (c) neutrino flux and magnetic dynamo. (d) internal pressure and gravity. 15. As fusion proceeds in the core of a star, the number of particles, and so the temperature of the core must to maintain core pressure. (a) increases, increase (b) increases, decrease (c) decreases, increase (d) decreases, decrease

4 ASTR 1P02 April 2016 Page 4 of The luminosity of a star is nearly constant while it stays on the main sequence, but in the long run there is (a) a very gradual decrease in luminosity. (b) a very gradual increase in luminosity. (c) a periodic change in luminosity. (d) [It depends on the size of the molecules that make up the star.] 17. The non-fusing core that remains immediately at the end of the lifetime of a mediummass star is called a (a) white dwarf. (b) red dwarf. (c) brown dwarf. (d) black dwarf. 18. A planetary nebula is (a) a huge cloud of gas and dust spewed forth when an idiot like Donald Trump opens his mouth. (b) a remnant of a high-mass star. (c) a remnant of a medium-mass star. (d) a remnant of a very low-mass star. 19. The spherical shell of material that forms a planetary nebula is pushed out by (a) the thermal and radiation pressure of the star s final red-giant stage. (b) the extremely energetic neutrino flux of the star s final red-giant stage. (c) the violent supernova explosion that follows the star s final red-giant stage. (d) the gamma-rays produced when matter falls into the black hole that results from the star s final red-giant stage. 20. Although planetary nebulae are typically approximately spherical, they appear to us to be shaped somewhat like a (a) ring. (b) parabola. (c) cone. (d) didgeridoo. (e) didgeridon t.

5 ASTR 1P02 April 2016 Page 5 of If a collapsing star has a mass greater than the Chandrasekhar limit, then it (a) usually spends a night in jail, with a stern warning not to do it again. (b) fails to leave the main sequence. (c) stops collapsing and becomes a pulsating green giant. (d) becomes a neutron star or black hole. 22. The range of observed radii of white dwarfs is approximately between (a) the radius of the Moon and the radius of the Earth. (b) the radius of the Earth and twice the radius of the Earth. (c) the radius of the Earth and ten times the radius of the Earth. (d) the radius of the Earth and twenty times the radius of the Earth. 23. Eventually, a white dwarf will stop emitting light, but this takes (a) several thousand years. (b) several million years. (c) several billion years. (d) a period of time comparable to the age of the universe. 24. The surface temperatures of white dwarfs are approximately (a) tens of thousands of degrees. (b) hundreds of thousands of degrees. (c) millions of degrees. (d) tens of millions of degrees. 25. Planetary nebulae emit light because (a) they are very hot. (b) they absorb ultraviolet light from a central white dwarf and then emit visible light. (c) they are full of degenerate electrons. (d) they are bombarded by numerous comets, which cause visible explosions. 26. A type Ia supernova occurs because of (a) the core collapse of a medium-mass star. (b) the core collapse of a high-mass star. (c) matter from a nearby star falling onto the surface of a white dwarf, becoming compressed and heated, and eventually resulting in an explosion. (d) matter from a nearby star falling onto the surface of a neutron star, becoming compressed and heated, and eventually resulting in an explosion.

6 ASTR 1P02 April 2016 Page 6 of A type II supernova occurs because of (a) the core collapse of a medium-mass star. (b) the core collapse of a high-mass star. (c) matter from a nearby star falling onto the surface of a white dwarf, becoming compressed and heated, and eventually resulting in an explosion. (d) matter from a nearby star falling onto the surface of a neutron star, becoming compressed and heated, and eventually resulting in an explosion. 28. The result of a type II supernova is, and an expanding cloud of gas and dust. (a) a white dwarf or neutron star (b) a neutron star or black hole (c) a white dwarf or black hole (d) a white dwarf, neutron star, or black hole 29. The helium flash is the onset of fusion of in the core of a star. (a) helium into carbon (b) hydrogen into helium (c) helium into boron (d) helium into beryllium 30. Distances to the most distant galaxies are determined using (a) the method of standard candelabras. (b) Type Ia supernovae. (c) Type II supernovae. (d) the method of planetary nebulae. 31. Observations by first showed that the Milky Way consists of many faint stars. (a) Aristarchus in 241 BC. (b) Brahe in (c) Galileo in (d) Hubble in established our location in the Milky Way by measuring the distances to. (a) Jacques Cousteau, starfish (b) Harlow Shapley, globular clusters (c) Fritz Zwicky, spherical bastions (d) Jocelyn Bell, LGMs

7 ASTR 1P02 April 2016 Page 7 of The diameter of the Milky Way is approximately (a) 100 light years. (b) 1,000 light years. (c) 10,000 light years. (d) 100,000 light years. (e) 1,000,000 light years. 34. Henrietta Swan Leavitt observed that there is a relationship between for the variable stars that she studied. (a) luminosity and mass (b) mass and temperature (c) period and luminosity (d) temperature and radius 35. The disk of the Milky Way contains (a) stars, star clusters, gas and dust. (b) stars, star clusters, but no gas and dust. (c) stars, gas and dust, but no star clusters. (d) stars, no gas and dust, and no star clusters. (e) gas and dust, but no stars or star clusters. 36. The halo of the Milky Way contains (a) stars, star clusters, gas and dust. (b) stars, star clusters, but no gas and dust. (c) stars, gas and dust, but no star clusters. (d) stars, no gas and dust, and no star clusters. (e) gas and dust, but no stars or star clusters. 37. The stars in the bulge of the Milky Way are similar to the stars in the halo, but the bulge also contains (a) some hot, luminous stars. (b) no very massive stars. (c) spiral arms. (d) no very young stars.

8 ASTR 1P02 April 2016 Page 8 of Dark matter was discovered by observing that (a) some unknown substances were exorcising regions of space haunted by ghostalinos. (b) there needs to be an opposite to balance light matter, and heavy matter has not been discovered. (c) some areas of space appear to be completely empty, but there must be something there, because nature abhors a vacuum. (d) the motions of disk stars (i.e., rotation curves) in spiral galaxies differed from those expected by applying Kepler s third law. 39. Dark matter consists of (a) TRUMPs (terribly repulsive, ugly megalomaniac pinheads). (b) WISHs (wildly improbable speculative hypotheses). (c) HIPHOPs (high-intensity powerful heliospherical oscillating particles) (d) [It is currently not known what dark matter consists of.] 40. The composition of the universe is currently inferred to be approximately (a) 5% ordinary matter, 25% dark matter, 70% dark energy. (b) 15% ordinary matter, 25% dark matter, 60% dark energy. (c) 25% ordinary matter, 25% dark matter, 50% dark energy. (d) 35% ordinary matter, 25% dark matter, 40% dark energy. 41. The Milky Way galaxy is (a) primarily made up of a certain brand of chocolate bars. (b) a spiral galaxy. (c) an elliptical galaxy. (d) an irregular galaxy. 42. About of the mass of the solar system is contained in the Sun. (a) 50% (b) 65% (c) 80% (d) 99.9% 43. The diameter of the Sun is about times the diameter of the Earth. (a) 10 (b) 100 (c) 1,000 (d) 1,000,000

9 ASTR 1P02 April 2016 Page 9 of The planet closest in size to Earth is (a) Mercury. (b) Venus. (c) Mars. (d) Neptune. 45. The distance of Jupiter from the Sun is about AU (Astronomical Units). (a) 1.5 (b) 5 (c) 10 (d) Pluto is now considered to be (a) an exoplanet. (b) a Jovian planet. (c) a retro planet. (d) a dwarf planet. 47. The only planets in the solar system that do not have any known satellites (i.e., moons) are (a) Mercury and Venus. (b) Mars and Neptune. (c) Jupiter and Saturn. (d) Uranus and Mercury. (e) Venus and Mars. 48. Jovian planets have longer rotation periods (days) than terrestrial planets. (a) True. (b) False. 49. Most asteroids are located (a) in the Kuiper belt. (b) along the orbit of Jupiter. (c) in the Oort cloud. (d) between the orbits of Mars and Jupiter.

10 ASTR 1P02 April 2016 Page 10 of Comets are (a) cars that were driven on the planet Mercury in the 1960s. (b) snowballs ejected from the underworld. (c) chunks of frozen gases with solid particles mixed in. (d) rocks that have broken off from planets. 51. Meteoroids are (a) muscular solar-system inhabitants who spend too much time in weight rooms and take performance-enhancing drugs. (b) small chunks of rock that leave a streak of light as they fly through Earth s atmosphere. (c) small chunks of rock that have landed on Earth after coming from outer space. (d) small chunks of rock that fly through the solar system. 52. The planet in our solar system with the largest diameter is (a) Jupiter. (b) Saturn. (c) Uranus. (d) Neptune. 53. Meteors are (a) a brand of automobile produced by General Motors from the late 1940s until the mid 1970s. (b) small chunks of rock that leave a streak of light as they fly through Earth s atmosphere. (c) small chunks of rock that have landed on Earth after coming from outer space. (d) small chunks of rock that fly through the solar system. 54. Meteorites are (a) a tribe of people who rivalled the Hittites in Anatolia in the 14th century BC. (b) small chunks of rock that leave a streak of light as they fly through Earth s atmosphere. (c) small chunks of rock that have landed on Earth after coming from outer space. (d) small chunks of rock that fly through the solar system.

11 ASTR 1P02 April 2016 Page 11 of As seen from above the Earth s north pole, (a) all planets orbit the Sun clockwise. (b) all planets orbit the Sun counterclockwise. (c) some planets orbit the Sun clockwise, and others counterclockwise. (d) [Some planets change their direction of motion around the Sun at various times in their orbits, sometimes moving clockwise and sometimes moving counterclockwise.] 56. Planets move around the Sun in orbits with the Sun at one focus. (a) hysterical (b) hyperbolic (c) elliptical (d) parabolic 57. As viewed from above the Earth s north pole, all planets spin counterclockwise except for (a) Venus and Uranus. (b) Jupiter and Saturn. (c) Mars and Neptune. (d) Mercury and Earth. 58. The two moons of Mars, Phobos and Deimos, are most likely captured (a) asteroids. (b) comets. (c) meteors. (d) meteorites. (e) meteoroids. 59. Kepler s third law relates a planet s to its. (a) distance from the Sun, orbital period (b) diameter, orbital period (c) distance from the Sun, rotational period (d) diameter, rotational period 60. The planet in our solar system with the smallest density is (a) Jupiter. (b) Saturn. (c) Uranus. (d) Neptune.

12 ASTR 1P02 April 2016 Page 12 of The best current theory we have for the formation of the solar system hypothesizes that the solar system formed because of (a) the collapse of a spinning cloud of gas and dust. (b) the explosion of a protostar. (c) the explosion of a protoplanet. (d) the explosion of a T-Tauri star. 62. A MACHO is (a) an overly-aggressive dude who is full of himself and has no empathy. (b) a satellite deployed to detect giant black holes. (c) a multiple-aperture confocal holistic observatory. (d) a massive astrophysical compact halo object. 63. A WIMP is (a) a cowardly dude who doesn t stand up for himself. (b) a satellite deployed to detect cosmic rays from the galactic nucleus. (c) a well-tempered interferometric molecular probe. (d) a weakly-interacting massive particle. 64. The spiral arms of the Milky Way contain (a) no gas and dust. (b) a lot of gas and dust. (c) a lot of gas, but no dust. (d) a lot of dust, but no gas. 65. On average, disk stars in the Milky Way contain percentage of heavy elements than stars in the bulge and halo. (a) a greater (b) a lesser 66. The Milky Way galaxy makes one rotation in about (a) 230 years. (b) 230 thousand years. (c) 230 million years. (d) 230 billion years.

13 ASTR 1P02 April 2016 Page 13 of To determine distances to nearby galaxies, up to 100 million light years away, astronomers use (a) the method of stellar parallax. (b) the method of Cepheid variables. (c) the method of globular clusters. (d) the method of superconducting supercolliders. 68. To determine distances to galaxies farther than 100 million light years, astronomers use (a) the method of stellar parallax. (b) the method of Cepheid variables. (c) the method of globular clusters. (d) the method of superconducting supercolliders. 69. Collisions between galaxies (a) are much more probable than collisions between stars. (b) are about equally probable as collisions between stars. (c) are much less probable than collisions between stars. (d) [Collisions between galaxies never occur.] 70. Radio galaxies are galaxies that (a) prefer radio advertising to TV advertising. (b) contain a large number of radio receivers. (c) emit intense radio waves. (d) contain so much dust that they disturb radio transmissions, especially in the evenings. 71. Quasars are (a) galaxies that emit a very large number of quasalinos. (b) black holes that emit intense gamma rays. (c) star-like objects that emit an intense amount of energy, and also emit an intense amount of radio waves. (d) neutron stars that emit intense pulses of radiation. 72. Hubble s law describes a relationship between (a) the distance of a galaxy and its recession speed. (b) the size of a galaxy and its rotational speed. (c) the mass of a galaxy and its pulsation rate. (d) the colour of a galaxy and its average parallax.

14 ASTR 1P02 April 2016 Page 14 of From Hubble s law, one can conclude that (a) the universe is pulsating. (b) the universe is rotating. (c) the universe is contracting. (d) the universe is expanding. 74. One can infer whether a galaxy is receding from us, or approaching us, and its relative speed, by analyzing its spectral (a) heliogram. (b) energy density. (c) parallax. (d) redshift. 75. Galaxies typically occur (a) in clusters. (b) isolated far from each other. (c) in beehive-like patterns. (d) in crystal-like patterns. 76. If the universe were infinite, existed for a very long time, and was uniformly filled with stars, then you could conclude that (a) the night sky should not be dark. (b) the Sun should have died long ago. (c) the solar system should be considerably smaller. (d) the Milky Way should contain much more dust than it actually has. 77. The observation that the night sky is dark implies that (a) there are a lot fewer stars than astronomers say there are, an obvious error that mainstream astronomers will not admit to making. (b) interstellar dust blocks light from distant stars. (c) the age of the universe is finite. (d) light from very distant stars gradually loses energy over its long journey (the tired-light hypothesis).

15 ASTR 1P02 April 2016 Page 15 of Observations of cosmic microwave background radiation provide strong evidence for (a) the Shaq-Kobe theory for how to win an NBA championship while feuding. (b) the Penzias-Wilson theory for the operation of radio telescopes. (c) the Slipher-Hubble theory for the recession of distant galaxies. (d) the Big Bang theory for the evolution of the early universe. 79. The cosmic microwave background radiation was first observed by (a) Robert Cousy and William Russell of the Cosmic Microwave Oven Corporation. (b) Tyson Chandler and Wilson Chandler of the Alley Oop Superstar Observatory. (c) Vesto Slipher and Edwin Hubble of the Mount Wilson Observatory. (d) Arno Penzias and Robert Wilson of Bell Laboratories. (e) Alexander Graham Bell of Wilson Laboratories. 80. An estimate for the age of the universe can be obtained (a) from the Big Band theory of Duke Ellington and Louis Armstrong. (b) by multiplying the speed of light by the average baryonic density of galaxies. (c) by taking the reciprocal of the Hubble constant. (d) by dividing the number of galaxies by the average time needed to form a galaxy. 81. At the beginning of the recombination era, about 400,000 years after the Big Bang, the universe had cooled enough that (a) central air conditioning was no longer required at the Hades offices of FIFA. (b) electrons and positrons could recombine into photons. (c) quarks could recombine into protons and neutrons. (d) protons and electrons could recombine into hydrogen atoms. (e) carbon and oxygen atoms could recombine into various molecules. 82. The ultimate fate of the universe depends on (a) the Toronto Maple Leafs hockey team winning a Stanley Cup in our lifetimes. (b) the rate of production of dark energy in black holes. (c) the average rate of supernova explosions per galaxy. (d) the average density of matter and energy in the universe. 83. The cosmological constant is (a) the rate at which protostars form in clouds of gas and dust. (b) the rate at which stars emit neutrinos. (c) the rate at which spiral galaxies evolve into elliptical galaxies. (d) the constant in Einstein s equation that corresponds to dark energy.

16 ASTR 1P02 April 2016 Page 16 of If the average density of the universe is large enough, then the universe (a) will be able to kick sand in the faces of those other universes that have been bullying it in the past. (b) will experience accelerated expansion. (c) will expand indefinitely. (d) will eventually stop expanding and re-collapse into a highly compact state. 85. If the average density of the universe is small enough, then the universe (a) will be able to get a job advertising weight-loss products. (b) will slow its expansion. (c) will expand indefinitely. (d) will eventually stop expanding and re-collapse into a highly compact state. 86. The latest observations on the overall curvature of the universe suggest that it (a) is nearly flat. (b) is very strongly positively curved, like a sphere or egg. (c) is very strongly negatively curved, like a hyperboloid. (d) has a large number of wormholes. 87. There is plenty of very good evidence for the Big Bang theory, including (a) energy production in stars. (b) crater formation in the early solar system. (c) collisions between galaxies. (d) cosmic microwave background radiation. 88. Astronomers made a startling observation in 1998, that about 4 billion to 5 billion years ago (a) the rate of energy production in stars began to decrease. (b) the emission of radio waves from Seyfert galaxies began to increase. (c) the average temperature of the universe suddenly decreased. (d) the expansion of the universe began to accelerate. 89. Strong evidence for the Big Bang theory of the origin of the universe is the (a) abundance of wealthy ignoramuses wishing to be U.S. president. (b) abundance of hydrogen and helium in the universe. (c) abundance of heavy metals in young stars. (d) abundance of organic molecules in the interstellar medium.

17 ASTR 1P02 April 2016 Page 17 of Measurements of recession speeds of distant galaxies suggest that (a) we must be near the centre of the universe, otherwise we wouldn t see the distant galaxies all receding away from us. (b) we might be anywhere in the universe, because all observers would see distant galaxies all receding away from them in about the same way. (c) [Distant galaxies are not receding from us.] 91. The largest asteroid in our solar system, called Ceres, has a diameter of about (a) 10 km. (b) 1,000 km. (c) 100,000 km. (d) 1,000,000 km. 92. Most of the asteroids in our solar system are located in (a) the Kuiper belt. (b) the Oort cloud. (c) the region between the orbits of Mars and Jupiter. (d) the Cassini gap. 93. Most asteroids in the main asteroid location of the solar system have orbits that are (a) prograde, nearly circular, and near the ecliptic. (b) prograde, highly elliptical, and near the ecliptic. (c) retrograde, nearly circular, and near the ecliptic. (d) retrograde, highly elliptical, and might be near or far from the ecliptic. 94. The average spacing between asteroids in the main asteroid location of the solar system is about (a) 10 m. (b) 1 km. (c) 1 thousand km. (d) 1 million km. 95. The Kirkwood gaps (a) are gaps in the front teeth of famous late-night comedian David Jimmy-Bob Kirkwood. (b) are zones in the main asteroid location of the solar system where there are relatively few asteroids. (c) are zones of weak magnetic field in sunspots. (d) are zones of the solar system where there are missing planets, according to the Titus-Bode law.

18 ASTR 1P02 April 2016 Page 18 of Meteoroids (a) are generally larger than asteroids. (b) are generally about the same size as asteroids. (c) are generally smaller than asteroids. (d) could be larger than, about the same size as, or smaller than asteroids. 97. Meteoroids are (a) made of green cheese, like the Moon. (b) solid, like asteroids. (c) loose clusters, like comets. (d) honey-comb-like, like honeycombs. 98. Most meteorites that strike the Earth are (a) irons. (b) woods. (c) stones. (d) stony-irons. (e) ironic stoners. 99. The nucleus of a comet resembles (a) a harbinger of doom. (b) a muddy baseball. (c) a sticky tarball. (d) a dirty snowball Most comets originate (a) in the Kuiper belt if they have short periods and in the Oort cloud if they have long periods. (b) in the Oort cloud if they have short periods and in the Kuiper belt if they have long periods. (c) in the asteroid belt if they have short periods and in the Costa del Sol if they have long periods. (d) in the Costa del Sol if they have short periods and in the asteroid belt if they have long periods.