Astronomy--Homework I Dr. Petersen The Museum of Space and Time, and The Story from Earth's Perspective (Read related chs.) 1. (T or F) A kiloparsec is a million parsecs. 2. (T or F) When we look out into space we look backward in time. 3. (T or F) 'Fixed stars' never move. 4. (T or F) 0 hours of right ascension is marked off on the celestial equator. 5. If you are a called a Capricorn, the sun at birth may not have been in the Capricorn constellation but could have been (for 2/3rds of the cases) in the constellation: A. Aquarius, B. Saggitarius, C. Aries, D.Taurus. 6. The seasons are caused by A. The sun's varying distance to the earth, B. The rotation of the earth, C. The tilt of the earth's axis, D. varying cloud cover. 7. Name an object that does not retrograde (turn around in its path seen from earth): A. Venus, B. Neptune, C. Mars, D. the Moon. 8. The reason the same side of the moon is always pointing toward the earth is A. chance, B. tidal locking, C. a different surface density on either side, D. a collision. 9. Ancients predating 1,000 BC evidently knew about A. the planet Uranus, B. telescopes, C. the precession cycle of the equinoxes, D. tidal forces. 10. Venus and Mercury never vary by more than a certain angle from the sun. The reason is A. they orbit the earth, B. they are planets with smaller orbital size, C. They have satellites. The Story From The Sun's Perspective: 11. (T or F) Copernicus' theory of planetary motion was more complex but better than Ptolemy's. 12. (T or F) Planets move in strictly circular orbits about the sun. 13. (T or F) The planet Pluto is moving fastest when it is farthest from the sun. 14. (T or F) Outer planets have smaller orbital periods than inner planets. 15. Who was the first in recorded history to realize that stars are actually like our sun? A. Giordano Bruno, B. Nicolas Copernicus, C. Claudius Ptolemy, D. Pythagoras. 16. Distance between foci of an ellipse divided by the widest diameter is called the A. mean diameter, B. eccentricity, C. radius, D. apothem. 17. The eccentricity of an ellipse is a measure of A. circularity, B. deviation from circularity (flatness), C. beauty, D. strangeness of the shape. 18. A comet moves slowest A. away from the sun, B. near the sun, C. near another planet. 19. Tycho Brahe was noted most for his A. telescope observations, B naked eye observations, C. calculations, D. theories of the solar system's motion. 20. Which of the following did Copernicus not assert A. Pythagoras was right about the size of the sphere of the stars, B. planets orbit the sun, C. Earth was interior in orbit to Mars, D. planets move on spheres. A Matter of Gravity: 21. (T or F) The greater the steepness of an inclined plane the slower a ball rolls down it. 22. (T or F) Motion is relative to the observer. 23. (T or F) Mass is the ratio of the net force on an object divided by its associated acceleration. 24. (T or F) The gravity between two objects depends more on one of their masses than the distance between them. I -2- 25. In considering motion, the perspective of a coordinate system tied to an observer is A. the x factor, B. the frame of reference, C. coordinated motion, D. not a basis for relativity. 26. An astronaut, after pushing off from the outside of a spacecraft will A. eventually fall back to the craft due to its gravity, B. speed up as she becomes free of the craft's gravity, C. Go very close to a constant velocity as she speeds away from the craft. 27. A skier pushes backward with the ski poles. The law responsible for the skier consequently accelerating forward is Newton's A. 1^st , B. 2^nd , C. 3^rd , D. a combination of 3^rd and 2^nd Law 28. Galileo discovered the first feature similar to earth's on an extraterrestrial body. What was it? A. riverbed on Mars, B. mountains on the Moon, C. ice on Pluto, D. rocks on Venus. 29. A rocket with twice the force of thrust, but half the mass will have A. half the acceleration, B. the same acceleration, C. twice the acceleration, D. 4 times the acceleration. 30. The mathematician who gave us the curved space idea Einstein used in his gravity theory was A. Euclid, B. Mach, C. Riemann, D. Emmy Noether. What is Light? 31. (T or F) Light is an electromagnetic wave. 32. (T or F) Light has rest mass. 33. (T or F) Light has a wavelength and a frequency which are related. 34. (T or F) The spectrum of light from a star has no gaps. It is truly continuous. 35. If we could bend it, how many times would light go around the earth in a minute? A. once, B. about eight times, C. about 480 times, D. about 64,000 times. 36. A wave communicates: A. Energy, B. Information, C. both A & B. 37. When we heat up a single element gas like hydrogen in a tube on earth we get off A. A continuous spectrum, B. a dark line (absorption) spectrum, C. a bright line (emission) spectrum. 38. A photon is A. a nuclear particle, B. a bundle of light energy, C. a planetesimal. 39. A blackbody curve's most important revelation is A. a limiting frequency, B. a limiting wavelength, C. a common or 'surface' temperature. 40. Doppler shifting toward lower frequency is a A. red shift, B. blue shift, C. yellow shift. Telescopes--Astronomy's Eyes. 41. (T or F) A refractor has mirrors. 42. (T or F) As you come closer to a distant object with a telescope, the rays become less parallel. 43. (T or F) Two stars less in angular distance than the resolution are not seen as separate. 44. (T or F) A lunar radio telescope (& earth's) could make an effective aperture the size of its orbit. 45. To effectively see x rays from space we need what type of telescope? A. Earth-based, B. Satellite. 46. A lens uses the following to focus rays: A. reflection, B. refraction, C. absorption. 47. In a city near a major observatory, using a street lamp with a smaller wavelength spread will help reduce, A. glare, B. light pollution, C. atmospheric turbulence, D. cost for telescopes. 48. Refractors have the following major disadvantages: A. chromatic aberration, B. its hard to build large ones, C. A & B. 49. The name of the satellite that discovered the first black hole means 'freedom' in Swahili. Its name was A. Nambo, B. Uhuru, C. Spaak, D. Dombo Tutu. 50. Light bends entering at an angle an interface between glass and water. The principle is A. reflection, B. refraction, C. specular reflection, D. absorption. Astronomy--Homework on Solar System (II) Dr. Petersen The Moon & Eclipses (read in notes and book) 1. (T or F) Ptolemy found the distance to the moon in earth diameters by observing its parallax. 2. (T or F) The moon's perigee is about 42,000 km different from its apogee. 3. (T or F) An eclipse occurs every time the moon and sun line up. 4. (T or F) The moon was formed by a collision of an asteroid with earth. 5. Solar eclipses have a cycle of about 18.6 years from total eclipse to total eclipse called: A. cycle of precession, B. Saros cycle, C. lunation cycle, D. eclipse cycle. 6. The points where the moon's orbit crosses the ecliptic plane is called A. Lagrangian points, B. lunar nodes, C. Roche limit. 7. The maria were formed before: A. the highlands, B. the regolith, C. the large craters, 8. We have evidence of past lunar volcanism in the A. maria, B. rills, C. floor of craters, D. A, B, & C. 9. The moon is A. a perfect sphere, B. a sphere with a bulge, C. oval shaped. 10. Volcanism on the moon ended about A. 4.6 million years ago, B. 3.9 billion years ago, C. 3.1 billion years ago. The Earth (read associated sections in notes and book): 11. (T or F) Oxygen is the molecule with the largest percentage of the atmosphere by weight. 12. (T or F) Astronauts can easily orbit within the Van Allen Belts. 13. (T or F) The solar wind is caused by the sun heating the air. 14. (T or F) The continents once composed one large continent called Pangea. 15. The combination of earth's crust and part of the mantle which makes up the techtonic plates is called the A. core, B. upper mantle, C. lithosphere, D. bathosphere. 16. The earth's core A. was always composed of iron, B. had iron settle into it in a molten state, C. is totally solid. 17. Major winds on earth are created by the rotation of the earth by means of a force called: A Coriolis, B. Magnetic, C. Gravitational, E. Electric. 18. The display of color in the north due to the solar wind particles orbiting earth's magnetic field is called: A. the Aurora Australialis, B. the Aurora Borealis, C. both A and B. 19. The age of the earth is also the: A. age of the galaxy, B. the age of the universe, C. the age of the moon, D. the age of the solar system, E. both C & D. 20. The age of the earth is A. 2.5 billion years, B. 4.6 billion years, C. 12 billion years. The Solar System (read related sections): 21. (T or F) The nebular theory of solar system origin seems to fit the facts more than other theories. 22. (T or F) Gravity and spin alone cannot account for the fact the planets formed in a disc-shaped region. 23. (T or F) A theory has been developed to explain why the planets are spaced as in Bode's Law. 24. We can measure the distance to planets from the earth using: A. measuring tape, B. spacecraft, C. radar ranging, D. sound waves. 25. Jupiter is roughly how many times the diameter of earth? A. 0.5, B. 6, C. 10, D. 36. 26. The sun is roughly how many times the diameter of Jupiter? A. 0.5, B. 6, C. 10, D. 36. II -2- 27. The dominant mode of rotation of the planets is called A. prograde, B. retrograde, C. clockwise. 28. Protoplanets are composed of A. protons, B. planetesimals, C. dust, D. hydrogen. 29. The mass of a planet is found by using the mass of the sun and A. Kepler's 1^st Law, B. Kepler's 3^rd Law, C. Newton's 2^nd Law. 30. Planetary atmospheric content depends on A. planetary surface gravity, B. surface temperature, C. A and B. The Inner Planets (read) 31. (T or F) Mercury's day is about twice the orbital period. 32. (T or F) All of Mercury has been mapped. 33. (T or F) You could survive on the surface of Venus with a lunar astronaut's spacesuit. 34. (T or F) Venus has intense acid rain. 35. The following molecule is not in Venus' atmosphere: A. carbon dioxide, B. Nitrogen, C. Oxygen. 36. The reason for Mercury's semiperiodic tidal locking may be a large crater called. A. Oreintale Basin, B. Caloris Basin, C. Tycho, D. Copernicus. 37. The person who theorized the greenhouse effect as responsible for the high temperature of Venus was A. Galileo, B. Carl Sagan, C. Fred Whipple, D. Bill Nye, the science guy. 38. Venus is surmised to have been hit by something large and flipped because of her A. prograde motion, B. retrograde motion, C. large crater. 39. Venus' atmospheric pressure is A. the same as earth's, B. ten times earth's, C. 90 times earth's. 40. What spacecraft landed on Venus? A. Mariner, B. Magellan, C. Venera. The Outer Planets, Comets, Asteroids, and Meteors (read): 41. (T or F) The radiation around Jupiter is very intense. 42. (T or F) We think life may reside on the outer portion of the ice crust of Europa, Jupiter's moon. 43. (T or F) Comets are as large as the average satellite. 44. (T or F) All asteroids are in orbit between Mars and Jupiter. 45. The land rover which landed on an ancient Martian lake bed is called A. Viking, B. Pathfinder, C. Surveyor, D. Voyager. 46. The Martian lake bed mentioned above is much like which lake on earth? A. Mono lake, B. Lake Superior, C. Dollar Lake, D. Lake Tahoe. 47. The Martian Olympus Mons, the largest volcanic cone in the solar system is: A. less tall than Mount Everest, B. equal to the height of Everest, C. several times higher than Everest. 48. Organic molecules made from methane may exist on the surface of which satellite? A. Io, B. Titan, C. Triton, C. Phobos. 49. The moon with the longest orbital period of any satellite is A. Miranda, B. Charon, C. Neried. 50. The asteroids that follow and precede Jupiter in a gravitational pit are called: A. Trojans, B. Amors, C. Achilles, D. Apollos. Astronomy--Homework on Sun and Stars (III) Dr. Petersen The Sun (read in notes and book) 1. (T or F) Over a hundred earths could be placed across the diameter of the sun, and the sun's mass is over 300,000 times that of earth. 2. (T or F) To run 28 100 watt light bulbs, it would take at least 2 square meters of solar panel. 3. (T or F) The hottest place in the sun is the corona. 4. (T or F) We get the expected amount of neutrinos reaching the earth from the sun. 5. The dominant process in solar energy production in the sun is A. nuclear fission, B. the p-p process, C. the CNO process. 6. It takes how long for energy from the core of the sun to reach the surface? A. a few seconds, B. 5 minutes, C. 1,000 years, D. 10 million years. 7. The sun's magnetic poles flip A. never, B. once every 12 hours, C. once every 11 years. 8. The extended period where there were no sunspots is called: A. the solar cycle, B. the Maunder Minimum, C. solar minimum. 9. The reason high temperatures are necessary to fuse hydrogen in the sun is A. need to cook to provide chemical change, B. to overcome electric repulsion of p's, C. to accelerate electrons. 10. The solar wind reaches earth: A. in a few seconds, B. at the speed of light, C. in a few days. Properties of Stars (read associated sections in notes and book): 11. (T or F) A star of 1.8 apparent magnitude is brighter than one at 3.6 magnitude. 12. (T or F) Flux is not related to the distance from the source. 13. (T or F) A G star is hotter than an M star. 14. (T or F) Parallax is a good method to find the distance to a star say 1300 LY away. 15. The power output at the source is A. Flux, B. Luminosity, C. Apparent brightness. 16. Flux from a source depends on A. its luminosity, B. the area over which the observer receives, C. both A and B. 17. The distance at which a star's parallax is one arc second is called A. a parsec, B. a Light Year, C. stellax. 18. The light flowing through the surface of a star is related to A. its surface temperature, B. its mass, C. its age, D. all of the above. 19. The continuous spectrum peak wavelength gives us the surface temperature by A. Boltzmann's Law, B. Wien's Law, C. the Law of Temperature. 20. The sun's temperature-color (spectral) classification A. O, B. A, C. G, D. M. The Formation and Structure of Stars (read related sections): 21. (T or F) An optical double is not a real binary. 22. (T or F) Mass is not the determining factor in stellar evolution. 23. (T or F) Cepheid variable stars vary with a period of 1-50 days and that helps yield their distance. 24. (T or F) Interstellar dust reddens light for the same reason the sky is blue. 25. O I is what ionization state of Oxygen? A. neutral, B. singly ionized, C. doubly ionized. 26. How many dips occur in the light curve of an eclipsing binary? A. one, B. two, C. none. 27. An example of a stellar nursery is A. The Orion Nebula, B. Population II stars, C. the solar system. III -2- 28. A protostar has not yet kindled nuclear fusion but glows: A. in the ultraviolet, B. in the infrared, C. with gamma ray emission. 29. A star just too small to kindle fusion, but glowing in the infrared is called A. a white dwarf, B. a brown dwarf, C. a black dwarf. 30. Large, hot young stars ionize an HII region (singly ionized) region around them called A. HI region, B. 'The zone', C. a Stormgren Sphere. Lives and Deaths of Stars (read) 31. (T or F) The heavier a star, the longer it lives. 32. (T or F) A star no longer burning H in the core is no longer on the main sequence. 33. (T or F) The earth's demise will happen by being engulfed in a Red Giant. 34. (T or F) A white dwarf is hotter on the surface than its surface on the main sequence. 35. The complete destruction of the white dwarf companion of a red giant is called A. a nova, B. a supernova type I, C. a supernova type II. 36. The light element Lithium (lighter than iron) was formed A. by fusion in a star, B. in a Supernova explosion, C. in a planet's core. 37. In the triple alpha process, three He nuclei make A. Lithium, B. Carbon, C. iron, D. mud. 38. Elements lighter than iron not formed in the triple alpha process are formed by what process? A. CNO, B. p-p, C. s and p, C. pasteurized process. 39. A white dwarf is A. still fusing elements, B. not fusing, but cooling off, C. larger than the sun. 40. A star with 1.1 solar masses in its remnant is a A. White Dwarf, B. Neutron Star, C. Black Hole. Neutron Stars and Black Holes (read): 41. (T or F) All neutron stars are pulsars. 42. (T or F) Pulsars may have 1 second between pulses. 43. (T or F) Black holes cannot be detected. 44. (T or F) The Pleiades is a Population I Open Cluster. Therefore it is gravitationally bound together. 45. The limit for a stellar remnant to form a black hole is how many solar masses or more? A. 1, B. 1.3, C. 3, D. 10. 46. Older stars are found in A. open clusters, B. globular clusters, C. stellar nurseries. 47. Whirling electrons produce radio radiation we call what type of radiation? A. synchrotron, B. cyclotron, C. radio jets. 48. You cannot return to the same place and time if you cross what boundary on a black hole? A. the ergosphere, B. the singularity, C. the event horizon, D. the accretion disk. 49. As you fall into a black hole, to a distant observer you appear to A. fall in normally, B. freeze and fade, C. turn blue. 50. The age of globular clusters is about how many billions of years? A. 1, B. 10, C. 12, D. 20.