AY 101-002 TEST #2 Spring 2009 Answer each of the following on a computer-gradeable answer sheet. Be sure to fill in your name and CWID number (and blacken their circles as well. Note the color of this test and turn in your answer sheet to the matching pile. 1. We know the sizes of some planets around other stars, measured from a) their infrared brightness. b) changes in the stars' Doppler shifts. C) HOW MUCH STARLIGHT THEY BLOCK WHEN SEEN IN FRONT. d) how big their images are on photographs. 2. The chemical building blocks of the solar system are broadly classified as a) earth, air, fire, and water. b) hydrogen, helium, lithium, beryllium. C) HYDROGEN/HELIUM, ICES, ROCK, AND METALS. d) terrestrial, Jovian, and cometary. 3. Which is not a result of the Earth's magnetic field? a) the Van Allen belts. c) the behavior of compass needles. b) aurorae. D) THE WEIGHT OF OBJECTS AT THE EARTH's surface. 4. The odd rotation and magnetic field of Uranus are thought to result from a) gravitational interaction with Jupiter. B) A MASSIVE IMPACT IN ITS EARLY HISTORY. c) its peculiar chemical makeup. d) a different origin than the other planets. 5. The huge difference in mass between the giant planets and the Earthlike ones a) means that there was once more rocky material in the outer solar system. b) probably means that many massive moons crashed into the giants. c) is caused by the giants' rapid rotation. D) IS DUE TO THE GIANTS' BEING ABLE TO RETAIN HYDROGEN AND HELIUM. 6. Which is most like the Moon in its surface features? A) MERCURY. c) Mars. b) Venus. d) Earth. 7. The most recent probe to land on Mars confirmed the presence of a) liquid water in streambeds. c) active volcanoes. B) SUBSURFACE ICE d) living bacteria. 8. We would expect a planet's primary atmosphere to be rich in A) HYDROGEN AND HELIUM. c) nitrogen and oxygen. b) hydrogen and oxygen. c) CO2. 9. The dark plains (maria) on the lunar surface are most like Earthly a) seabeds C) LAVA FLOWS b) deserts. d) salt flats. 10. Young stars are often accompanied by a) planetary nebulae. b) formation of black holes. C) ORBITING DISKS OF GAS AND DUST. d) swarms of giant planets. 11. The giant planets are so massive because a) there was so much ice in the outer solar system. b) the Earth started out as one of their moons. C) THEY ARE COLD ENOUGH TO RETAIN HYDROGEN AND HELIUM. d) they have been hit by many hydrogen-rich comets. 12. The great majority of lunar craters are almost circular, because a) the Moon's gravity forces infalling objects into a vertical path. B) IMPACTING OBJECTS EXPLODE VIOLENTLY ON CONTACT WITH A SURFACE. c) lunar volcanoes are so energetic. d) the Moon's crust is very thin. 13. Our deepest information on the Earth's interior comes from a) deep undersea drilling. C) EARTHQUAKE SHOCK WAVES. b) the chemistry of volcanoes. d) the composition of crustal rocks. 14. If a planet has a denser core, this suggests that A) IT WAS MOLTEN AT ONE TIME. c) it originated outside the Solar System. b) it formed in more than one step. d) it is mostly liquid. 15. Advantages of reflecting telescopes over refractors do not include A) HIGHER MAGNIFICATION. c) lack of color aberration. b) construction in larger sizes. d) more compact designs. 16. Einstein's relativity encompasses the fact that a) no physical quantity can be measured exactly. b) matter and energy are separately conserved and distinct. C) THE SPEED OF LIGHT IS INDEPENDENT OF THE MOTION OF ITS SOURCE OF OBSERVER. d) all measurements in the Universe are relative to the Earth's location. 17. Jupiter's Great Red Spot is most like a terrestrial a) lava flow. c) desert. b) ocean. D) STORM. 18. The odd rotation and magnetic field of Uranus are thought to result from a) gravitational interaction with Jupiter. B) A MASSIVE IMPACT IN ITS EARLY HISTORY. c) its peculiar chemical makeup. d) a different origin than the other planets. 19. The huge difference in mass between the giant planets and the Earthlike ones a) means that there was once more rocky material in the outer solar system. b) probably means that many massive moons crashed into the giants. c) is caused by the giants' rapid rotation. D) IS DUE TO THE GIANTS' BEING ABLE TO RETAIN HYDROGEN AND HELIUM. 20. Most of the interior of Jupiter and Saturn is probably composed of a) ice. b) dense, rocky cores. c) gaseous atmospheric layers of hydrogen and helium. D) METALLIC HYDROGEN. 21. The great puzzle unveiled by the exploration of Mars has been a) how water remains in channels at such low temperatures. B) WHY THERE ARE SURFACE FEATURES MADE BY WATER ON SUCH A COLD AND DRY WORLD. c) how its tiny moons can have such pronounced tidal effects. d) why it shows no impact craters while orbiting near the asteroid belt. 22. A concentration of ozone at high altitudes in our atmosphere a) traps heat. c) is produced by the Earth's magnetic field. B) ABSORBS ULTRAVIOLET RADIATION. d) reflects radio waves back to the surface. 23. The energy to drive weather patterns on Earth comes from a) changes in the strength of the greenhouse effect. B) DIFFERENCES IN SOLAR HEATING ON VARIOUS PARTS OF ITS SURFACE. c) the Earth's hot core. d) a gradual slowdown of the Earth's rotation. 24. The huge difference in surface conditions between Venus and Earth is A) CAUSED BY A GREAT DIFFERENCE IN STRENGTH OF THE GREENHOUSE EFFECT. b) a lack of volcanic activity building up landforms on Venus. c) Venus not having a big moon (or any moon, for that matter). d) the high density of water vapor in Venus' cloud layers. 25. Plate tectonics on Earth entails A) ITS CRUST BEING MADE OF A NUMBER OF LARGE SOLID BUT MOVING PIECES. b) blocks of crustal rock rising and falling. c) new continents appearing from ocean crust. d) movement of continents during ice ages as glacial "plates" appear. 26. If the surface of a rocky world has few impact craters, this suggests that A) OTHER PROCESSES ARE WIPING OUT CRATERS FASTER THAN THEY FORM. b) its surface is very porous and deep. c) it must have a thick atmosphere. d) the planet has only recently arrived in the solar system. 27. The greenhouse effect happens because A) OUR ATMOSPHERE TRANSMITS VISIBLE LIGHT AND ABSORBS INFRARED RADIATION. b) our atmosphere transmits infrared radiation and absorbs visible light. c) ozone absorbs ultraviolet light. d) like greenhouse glass, air layers prevent different levels from mixing. 28. Available data indicate that the planets formed a) when another star nearly collided with the young Sun. B) FROM AN ORBITING DISK OF GAS AND DUST AROUND THE YOUNG SUN. c) from material ejected from its atmosphere as the Sun heated up. d) independently of the Sun, being captured later by its gravity. 29. The planets closest to the Sun have the largest proportion of A) METALLIC ELEMENTS. c) ices. b) rocky material. d) hydrogen and helium. 30. Many of the planets known around other stars are a) rocky, Earthlike planets at low temperatures. b) massive Jupiter-like planets orbiting far from the stars. C) MASSIVE JUPITER-LIKE PLANETS ORBITING VERY CLOSE TO THE STARS. d) orbiting far from the stars' equatorial planes. 31. Many planets have been found around other stars, most of them by a) the miniscule dimming of the stars as planets pass in front of them. b) Hubble images showing the faint, moving planets. C) CHANGES IN THE STARS' DOPPLER SHIFTS AS THEIR PLANETS ORBIT. d) radio waves from their intense radiation belts. 32. Cold dust particles in deep space are best seen using a) radio telescopes. c) ultraviolet telescopes. B) INFRARED TELESCOPES. d) X-ray telescopes. 33. Which of the following can only function beyond the Earth's atmosphere? a) radio telescopes. C) X-RAY TELESCOPES. b) neutrino detectors. d) spectrographs. 34. A major drawback to refracting telescopes is caused by a) their long tubes compared to reflectors. B) SINGLE LENSES FOCUSSING LIGHT OF DIFFERENT WAVELENGTHS AT DIFFERENT POINTS. c) their inability to track the sky as the Earth rotates. d) their small fields of view. 35. The Earth's atmosphere limits astronomy a) by absorbing most kinds of radiation. b) by blurring radiation passing through it. c) by reflecting artificial light in the air for large distances. D) IN ALL OF THE ABOVE WAYS. 36.The Apollo program was largely motivated by a) science c) territorial claims. B) COLD WAR COMPETITION. d) technological spinoffs. 37. We can tell how long a planetary surface has been relatively undisturbed from a) volcanic features. c) its atmosphere B) THE NUMBER OF CRATERS. d) its chemistry. 38. A planet's internal heat is reflected directly by A) VULCANISM. c) crater size. b) gradation. d) distance from the Sun. 39. All other things equal, we do not expect larger planets to have more a) core heat. c) volcanic activity b) massive atmospheres. D) IMPACT CRATERS. 40. The Earth shows many fewer craters than the Moon because A) EROSION WIPES THEM OUT. c) the Moon stops them. b) it gets fewer impacts. d) it has less ongoing volcanic activity. Assessment qustions: 41. Jupiter's moon Europa interests those seeking extraterrestrial life because A) IT APPEARS TO HAVE AN EXTENSIVE OCEAN BELOW THE SURFACE. b) it shows spectroscopic features of chlorophyll. c) its atmosphere is rich in oxygen. d) it lies far from Jupiter's damaging radiation belts. 42. Long-term changes in the solar cycle have coincided with changes in a) meteor showers. C) THE EARTH'S CLIMATE. b) the Earth's orbit. d) the Sun's rotation. 43. One kind of supernova explosion is triggered by a) the violent winds of hot stars. b) the onset of helium fusion in a giant star. c) the helium flash in a red supergiant. D) THE PRODUCTION OF AN IRON-RICH CORE IN A MASSIVE STAR. 44. X-ray emission is a particularly good way to find black holes a) within only our Galaxy. b) when they are located far from other objects. C) WHEN THEY ARE SURROUNDED BY INFALLING MATERIAL. d) shortly after their formation. 45. Over cosmic time, the number of quasars a) has stayed roughly constant. B) INCREASED RAPIDLY AND HAS DECLINED FOR MOST OF COSMIC HISTORY. c) has increased to today's value. d) has continuously decreased.