PHYS 160 Astronomy Test #3 Nov 1, 2017 Version B

PHYS 160 Astronomy Test #3 Nov 1, 2017 Version B

I. True/False (1 point each) Circle the T if the statement is true, or F if the statement is false on your answer sheet. 1. The clouds of Jupiter are composed primarily of water vapor. 2. Nitrogen comprises the majority of Earth s atmosphere. 3. Not all asteroids stay in the asteroid belt. 4. All meteors that enter Earth s atmosphere result in meteorites. 5. Pluto is sometimes closer to the Sun than Neptune. 6. Approximately 200 extrasolar planets have been found so far. 7. Maria are regions on the moon that formed when large amounts of water eroded the surface during its history. 8. Meteor showers can be caused by Earth moving though debris left behind by a comet. 9. Our solar system is approximately 80 light-years in diameter. 10. Springtides only occur during the Spring season.

II. Definitions (1 point each). There are 10 definitions given. Select the word or phrase that best matches the definition from the table of words below. Put your answer on the answer sheet. Note, there are more words than there are definitions, so not all of them will be matched. asteroid scarp troposphere Habitable zone crater Trans- Neptunian Object Neap tide aurora Spring tide meteorite Kuiper belt stratosphere Oort cloud magnetosphere meteor maria highlands ionosphere Ejecta blanket Greenhouse effect asteroid meteoroid Van Allen belt Escape velocity Definitions: 1. A circular depression on a celestial body caused by an impact of a meteoroid, asteroid, or comet or by a volcano. 2. Two flattened, donut-shaped regions around the Earth where many charged particles are trapped by the Earth s magnetic field. 3. Large, relatively crater-free plains on the Moon. 4. A large (greater than 100 m in diameter) rock in interplanetary space. 5. The trapping of infrared radiation near a planet s surface by the atmosphere. 6. Light radiated by atoms and ions in the Earth's upper atmosphere that have been carried there by the Earth's magnetic field entering the atmosphere at the Earth's polar regions. 7. The streak of light seen when any space debris vaporizes in the earth s atmosphere; a shooting star. 8. A hollow spherical region of the solar system far beyond the orbit of Neptune where most comets are believed to spend most of their time. 9. The region around a star wherein water can exist in liquid form on a planet s surface and, life as we know it can conceivably exist. 10. A cliff on the Moon or Mercury believed to have formed when those bodies cooled and shrank.

III. Multiple Choice (1 point each) Select the letter next to the best answer for each question. Circle the letter on your answer sheet. 1. Spirit and Opportunity are a. 2 rovers on Mars b. 2 moons of Mars c. 2 satellites orbiting Mars d. 2 space shuttles 2. Kepler, the orbiting telescope, looks for a. the infrared signature of a planet b. the wobble that a planet produces when orbitting its parent star c. the temporary dimming of light in a star as a planet orbits it d. the atmospheric spectra from a planet 3. A comet's gas tail is always aligned in a direction, from the comet head a. towards the sun, because of gravitational attraction b. in a direction along its orbital path, always behind the comet c. away from the sun d. towards the nearest planet, because of mutual gravitational attraction 4. A planetary system around a nearby star might be detected by a. observing a planet with a very large telescope in space b. by measuring the parallax of the star c. by measuring the Doppler shift of the planet d. by detecting the orbit of the star as it reacts to the motion of the planets 5. Both the moon and Mercury have very large temperature variations between day and night. the main reason for this large variation is a. small mass. b. rocky composition. c. distance from the sun. d. lack of atmosphere. e. lack of surface water. 6. In order for people to survive on Mars, which factor would pose the most difficult problem? a. low surface pressure. b. lack of surface water in liquid form. c. low surface gravity. d. rusted iron in the soil.

7. Jupiter's moon Io has no observable impact craters because a. volcanic activity has covered them over. b. its proximity to Jupiter prevents large impacts. c. the surface is molten and meteorites sink into it. d. a thick atmosphere keeps us from seeing the surface. 8. Which solar system body is believed to have deep oceans of liquid water under a surface of solid ice a. Io b. Titan c. Triton d. Europa e. Pluto 9. Why are meteorites and comets important in studying the origin of the solar system? a. they have recently formed, themselves. b. they are recently produced fragments of planets. c. they represent the material which formed the planets. d. they are in the process of forming new moons and planets 10. Mercury is the hottest planet because a. it is the closest planet to the Sun b. one side is always facing the Sun c. Mercury does not rotate d. None of the above. Mercury is not the hottest planet. 11. The blue-green appearance of Uranus is caused by a. scattering of light from the dust in the thick atmosphere b. the color of the surface of the planet c. the reflection of blue light by the ice crystals on the planet's surface in its atmosphere d. the atmosphere of methane gas, which absorbs red light 12. The clouds on Jupiter appear banded because of a. erosion on the surface b. heating effects from the sun c. motion of its moons d. its rapid rate of rotation e. different elements in the atmosphere 13. The major constituents of the Earth's atmosphere are a. 95% carbon dioxide, some water vapor b. 77% nitrogen, 21% oxygen c. 77% oxygen, 21% nitrogen d. methane, ammonia, water vapor and carbon dioxide in about equal amounts

14. If a hits the Earth s atmosphere and does not burn up as a, it can fall to the Earth s surface and be found as a. a. meteorite, comet, meteoroid b. meteor, meteorite, comet c. meteoroid, meteor, meteorite d. comet, meteor, meteorite 15. The 4 largest moons of Jupiter were first discovered by which of the following scientists? a. Johannes Kepler b. Tycho Brahe c. Isaac Newton d. Galileo Galilei e. William Herschel 16. What is surprising about the extrasolar planets that have been discovered so far? a. Many of them are giant planets like Jupiter, but their location is close to the star, where only terrestrial planets should form. b. Many of them are terrestrial size planets, but they are at a location far from the star, where only jovian type planets should form. c. More than half of them show spectra containing molecular oxygen, a possible indication of life on these planets. d. The majority of them rotate much faster than the planets in our solar system. 17. Which is a moon of Jupiter? a. Callisto b. Titan c. Triton d. Umbriel e. Charon 18. The great red spot is a. a continent. b. a storm. c. an optical illusion. d. a shadow of one of Jupiter's moons on its surface. e. a mountain protruding above Jupiter's atmosphere. 19. The asteroid belt is located a. between Earth and Mars b. between Mars and Jupiter c. between Jupiter and Saturn d. none of the above

20. The planet that is most nearly like Earth in size is a. Venus b. Mercury c. Mars d. Pluto 21. A comet nucleus is mainly made of a. Carbon b. Hydrogen c. Rock d. Iron e. Ice 22. As the solar nebula collapsed, a. angular momentum was conserved b. it gradually flattened to a disk-shaped cloud c. the bulk of the gases ended up in the Sun d. all of the above 23. Tides are caused by a. a bulge in the Earth's surface b. magnetic fields between the Earth and the moon c. gravitational attraction of the moon and the sun on the oceans d. no choice 24. Which of the following statements is not true about our solar system? a. All planets orbit the Sun in the same direction. b. The Sun rotates in the same direction as the planets orbit the Sun. c. The planets orbits lie almost in a flat plane. d. All planets rotate on their axis in the same direction. 25. Which of the following planets has no moon? a. Venus b. Neptune c. Mars d. Pluto 26. Why do most meteoroids not reach the surface of the Earth? a. they bounce off the atmosphere and go back into space b. they burn up in the atmosphere c. they are light enough to remain suspended in the air d. they land in the ocean e. the statement is false. Almost all land on Earth, but most are not found.

27. The smallest planet is a. Neptune b. Mars c. Mercury d. Venus e. Pluto 28. The largest known asteroid in our solar system is a. Gaspra b. Titan c. Pallas d. Ceres e. Mathilde 29. The planets are thought to have a. originated in the cloud of dust and gas from which the sun formed b. been captured when they came close to the sun c. resulted from the near passage of a star d. resulted from an explosion in the sun 30. The two moons of Mars are named a. Ceres and Pallas b. Io and Europa c. Galileo and Copernicus d. Helios and Juno e. Phobos and Deimos

IV. Short Answer Questions Answer any five (5) of the following questions. Each question is worth 10 points. Answers may contain paragraphs, lists, and drawings. Please put your answers on the white paper provided. 1. Describe Pluto. What makes it a dwarf planet and not a planet? Describe a recent mission to study Pluto and its moons. 2. Compare and contrast Terrestrial and Jovian planet types. Name the planets in each type. 3. Describe the Greenhouse Effect and its role in Venus and Earth s temperatures. 4. What are NASA s main goals for Mars exploration? Describe a recent mission to Mars. 5. What are the remaining obstacles that must be solved to get humans to Mars? 6. Describe ion propulsion. What recent mission used this type of engine? What are the advantages and disadvantages of ion propulsion? 7. What factors make a moon or planet a good candidate for finding life? What places in our solar system are likely candidates for finding life beyond Earth?