Practice Test #3

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    • Lecture 15

    1. True or False: The same face of the moon always faces the Earth.

    2. Since the average density of the moon is about 3 gm/cm3, we can conclude that
      1. the water on the moon must be trapped in the rocks
      2. there must not be a massive iron/nickel core inside the moon.
      3. there must be active volcanoes on the moon
      4. there must be a massive lithium core in the moon.
      5. none of the above

    3. Based on radioactive dating, the oldest rocks on the moon are
      1. about 5.6 billion years old
      2. about 4.4 billion years old.
      3. about 1.3 billion years old.
      4. about 4.3 million years old
      5. about 2.3 million years old

    4. Which of the following is currently the best theory for the formation of the Moon?
      1. the Co-accretion theory: the Moon and Earth were formed next to each other from the same material.
      2. The Spontaneous Eruption theory: the planet Venus formed the Moon/
      3. The Giant Impact theory: a big object collided with the Earth and the debris formed the Moon.
      4. the Fission theory: the Moon split from the Earth because of the Earth's initial high rotation speed.
      5. The Capture theory: the Moon was formed elsewhere and was orbitally captured by the Earth.

    5. One of the most important scientific results obtained during the Apollo missions to the was
      1. the detection of a thick oxygen atmosphere on the moon.
      2. the discovery of craters on the moon's surface.
      3. the discovery of how the cratering rate in the solar system has changed over its history
      4. the detection of the slow rotation of the moon.
      5. the discovery of abundant amounts of cheese covering the moon's surface.

    6. Which of the following are not types of geological features seen on the Moon?
      1. impact craters and rays
      2. maria and basins
      3. limbs and terminators
      4. mountains and valleys
      5. all of the above are geological features that can be seen on the Moon.

    7. True or False: Maria are regions on the moon that formed when large amounts of water eroded the surface during its history.

    8. The atmosphere of the moon is BEST described as:
      1. dense with large amounts of carbon dioxide.
      2. low density, but made mostly of carbon dioxide.
      3. very low density, almost a complete vacuum.
      4. medium density, made mainly of nitrogen and oxygen.
      5. thick and rich chocolate.

      Lecture 16

    9. How do we measure the age of a planet's surface using spacecraft? Why do we think some surfaces are young and some are old? How was this method tested against other dating techniques?

    10. The terrestrial planets are, in order of increasing distance from the Sun:
      1. Mars, Venus, Earth, Mercury.
      2. Mercury, Venus, Earth, Mars.
      3. Mercury, Mars, Venus, Earth.
      4. Earth, Mercury, Mars, Venus.
      5. Venus, Mercury, Earth, Mars.

      Lecture 17

    11. Although Mercury is much small than the Earth, it has a/an _____ about the same as the Earth.
      1. average density
      2. atmosphere
      3. surface gravity
      4. temperature
      5. rotation period

    12. Which planet's rotation is tidally locked to its revolution in a 3 to 2 resonance
      1. Mercury
      2. Venus
      3. the Moon
      4. Mars
      5. None of the above

    13. Which of the following describes the atmosphere of Mercury:
      1. thick carbon dioxide atmosphere.
      2. thin carbon dioxide atmosphere.
      3. very thin sodium atmosphere, probably formed from the solar wind
      4. there is no evidence of any gases on Mercury
      5. nitrogen and oxygen, some carbon dioxide.

    14. Which of the following describes the geological features of Mercury:
      1. many craters; large iron core.
      2. evidence of ancient rivers.
      3. massive volcanoes, many ancient lava flows.
      4. widespread erosion from the solar wind; very flat landscape
      5. plate tectonics, crustal motion.

    15. As the science officer on a starship, you approach a planet which has its rotation tidally locked to its orbit around the star Sirius. Which of the following is probably true about this planet?
      1. There is probably a strong magnetic field due to synchronous rotation.
      2. There is probably a weak magnetic field due to the slow rotation.
      3. The magnetic field is probably very similar to Earth's.
      4. The magnetic field is not linked to rotation, so we cannot conclude anything about its strength.

    16. Which planet's rotation is tidally locked to its revolution in a 3 to 2 resonancy?
      1. Mercury
      2. Venus
      3. the Moon
      4. Mars
      5. none of the above

    17. The surface of Mercury is best described as
      1. very smooth, almost no surface features
      2. covered with some craters, mountains, and large volcanoes
      3. heavily cratered
      4. eroded, apparently from water flowing on the surface.

    18. Observations of Mercury from the Earth have always been difficult primarily because
      1. Mercury can only be seen in the early evening and just before sunset since it is always visible close to the sun.
      2. Mercury is more distant than all the other planets.
      3. Mercury is covered by a thick atmosphere than obscures its features
      4. Mercury is too hot to be seen in optical telescopes
      5. Mercury cannot orbit in a retrograde direction.

    19. Which of the following planets are not currently warmed by the Greenhouse Effect.
      1. Mercury
      2. Venus
      3. Earth
      4. Mars

      Lecture 18

    20. The atmosphere of Venus is best described as
      1. Very dense with large amounts of carbon dioxide.
      2. Low density, but made mostly of carbon dioxide.
      3. Very low density, almost a complete vacuum.
      4. Medium density, made mainly of nitrogen and oxygen
      5. "As thick as pea soup on a hot summer's day"

    21. Which planet's revolution is in the opposite direction of its rotation?
      1. Mercury
      2. Venus
      3. Mars
      4. Jupiter
      5. None of the above

    22. What evidence is there of active volcanoes on Venus
      1. photographs of volcanic dust clouds.
      2. radar images of changing lava flows.
      3. changes in the atmospheric composition caused by outgassing.
      4. ultraviolet measurements of surface activity.
      5. there is no evidence of active volcanoes on Venus.

    23. Venus rotates
      1. 3 times for every 2 orbits.
      2. in about 24 hours.
      3. prograde and takes 243 days
      4. retrograde and takes 243 days
      5. in 88 days.

    24. Venus rotates east to west (retrograde). This was discovered by radar.
      1. correct.
      2. wrong: Rotation must be from west to east to be called retrograde.
      3. wrong: It was discovered by optical telescopes.
      4. wrong: It was discovered by a Soviet probe landing on Venus
      5. wrong: both B and D are correct answers.

    25. The clouds of Venus are composed of droplets of
      1. water
      2. nitrogen
      3. carbon dioxide
      4. salt
      5. sulfuric acid.

    26. The atmosphere of Venus is mostly
      1. oxygen
      2. nitrogen
      3. carbon dioxide
      4. neon
      5. sulfuric acid

    27. Venus is thought to be hot because of the greenhouse effect. This means
      1. Venus is covered with glass
      2. Venus is green
      3. radiation can't get to the surface of Venus since it has clouds
      4. the carbon dioxide clouds keep the surface heat of Venus from radiating.
      5. both A and B

    28. The temperature on the surface of Venus is
      1. a. about 100K
      2. about 300 K
      3. about 750K
      4. about 1,500K
      5. about 10,000L

      Lecture 19

    29. Is there life on Mars? Discuss the case for life on Mars an the case against. Why did we search for life in the Viking missions and what were the results? As always, be brief.

    30. One of the features that was seen on the Martian surface by the Viking and Mariner spacecrafts that was not seen on Mercury, Venus or the Moon is
      1. canals crossing the surface from the polar caps.
      2. mountains formed by volcanic outgassing.
      3. impact craters.
      4. runoff channels
      5. "weird terrain."

    31. Which of the following describes the rotation period of Mars?
      1. tidally locked in a 3:2 spin orbit resonance with its orbit around the sun.
      2. very slow and retrograde
      3. prograde with a period of about 24 hours.
      4. synchronous; the same face always points toward the sun.
      5. impossible to determine.

    32. The most likely reason why life has evolved on Earth instead of Mars is
      1. the abundant amounts of liquid water.
      2. the high amounts of carbon dioxide in the early atmosphere
      3. the abundant amounts of iron in the soil.
      4. the large amounts of oxygen in the atmosphere.
      5. the 23.5 degree tilt of the planet.

    33. The best evidence that liquid water was once on Mars is
      1. the dry river beds seen on the surface.
      2. the clouds seen in the atmosphere by orbiting space craft.
      3. the rotation period.
      4. the large polar ice caps.
      5. the fossils of sea life seen by the Viking experiment.

    34. The rotational period of Mars is about
      1. 2 hours, 10 minutes
      2. 6 hours
      3. 3 days
      4. 59 days
      5. not near any of these.

    35. The most common gas in the atmosphere of Mars is
      1. carbon dioxide
      2. nitrogen
      3. oxygen
      4. gaseous water
      5. none of these.

    36. The channels on Mars discovered by Mariner 9 show
      1. that intelligent life once existed on Mars.
      2. that there were flaws in the Mariner 9 design.
      3. that there was most likely free water on Mars.
      4. that Schiaparelli was right.
      5. misleading: there are no channels on Mars.

    37. All of the Viking experiments could be interpreted to show that life exists, or at least once existed, on Mars.
      1. Correct.
      2. Wrong: Organic molecules were not found, and other experiments were ambiguous.
      3. Wrong: All biological experiments were strongly negative.
      4. Wrong. Only one experiment positively detected life.
      5. Misleading: No Viking experiment checked this.

    38. We expect the surface of Titan to be covered with liquid
      1. water
      2. hydrogen
      3. helium
      4. methane
      5. sulfur dioxide.

    39. The region on Mars known as the "Valles Marineris" is a huge canyon big enough to be visible from Earth. What is the most likely cause for its formation?
      1. water erosion from the runoff channels
      2. wind erosion from the dust storms
      3. volcanic flows from Olympus Mons
      4. tectonic fracturing of the surface
      5. extensive mining by Martians.

    40. One feature on Mars seen by ground-based optical telescopes is
      1. craters
      2. volcanoes
      3. polar ice caps
      4. heavy cratering covering the planet.
      5. Martian cities.

    41. Which planet is the most similar to Earth in terms of its mass and size?
      1. Mercury
      2. Venus
      3. Mars
      4. Uranus
      5. None of the above

      Lecture 20

    42. The Jovian planets are mainly composed of
      1. carbon dioxide
      2. hydrogen
      3. helium
      4. methane
      5. ammonia

    43. The magnetic field of Jupiter is probably caused by
      1. gaseous hydrogen and the Great Red Spot
      2. liquid helium in the outer atmosphere
      3. a metallic hydrogen core
      4. interactions with the moon Io.

    44. Which of the following planets and moons have active volcanoes?
      1. Io
      2. Mercury
      3. Mars
      4. Jupiter
      5. a and d

    45. The volcanoes on Io are caused by the internal heating of
      1. Jupiter from radioactive elements.
      2. Io from radioactive elements.
      3. Io from tidal forces from Jupiter
      4. Io from its slow gravitational collapse.

    46. Measurements of Jupiter' temperature show that it is warmer than expected. The extra heat that we detect is probably from
      1. Jupiter's rotation rate.
      2. Jupiter's strong magnetic field.
      3. synchrotron radiation.
      4. the slow gravitational contraction of Jupiter
      5. the Greenhouse Effect

    47. Jupiter rotates with a period of about _____ hours
      1. 2
      2. 5
      3. 10
      4. 24
      5. 100

    48. The moons of the Jovian planets usually are
      1. in synchronous rotation with their orbit.
      2. made of ices and dusts.
      3. orbiting the same direction as the planet rotates.
      4. all of the above.

    49. Synchrotron radiation emitted from Jupiter is caused by
      1. the solar wind interacting with Jupiter's strong magnetic field.
      2. Jupiter's rapid rotation and magnetic field
      3. thermal heating from the slow gravitational collapse.
      4. Jupiter's moon Io.

    50. The Great Red Spot on Jupiter is thought to be
      1. a volcanic outburst
      2. a very old storm.
      3. a shield volcano.
      4. a magnetic vortex.
      5. a rotating sphere of gas.

    51. True or False: Jupiter has more mass than all the other planets combined.

    52. One of the largest satellites is Titan, which circles
      1. Jupiter
      2. Mars
      3. Saturn
      4. Uranus
      5. None of these.

    53. Which of the following planets and moons CURRENTLY has large amounts of liquid water?
      1. Mars
      2. Venus
      3. Europa
      4. Callisto

    54. Which of the following planets has the highest rotation rate?
      1. Mercury
      2. Earth
      3. Jupiter
      4. Saturn
      5. Uranus

    55. The largest planet in the solar system is
      1. Earth
      2. Jupiter
      3. Saturn
      4. Uranus
      5. Pluto

    56. Which planet's rotation is only about 8 hours long?
      1. Mercury
      2. Venus
      3. the Moon
      4. Mars
      5. None of the above

      Lecture 22

    57. One of the unusual features about the moon Titan is
      1. its rotation is tidally locked in its orbit around Saturn.
      2. its orbit is retrograde compared to Saturn's rotation.
      3. It has a thick atmosphere that obscures the surface.
      4. it passes through the rings of Saturn twice every orbit.
      5. It has unusual cratering on one side only.

    58. The density of Saturn is best described as:
      1. about the density of iron.
      2. about the density of rocks found on Earth's surface.
      3. about the density of liquid water.
      4. about the density of Earth's atmosphere

    59. The rings of Saturn are best described as
      1. a solid disk of material with Saturn at the center.
      2. a disk of gas orbiting Saturn
      3. a disk of microscopic dust particles orbiting Saturn
      4. a disk of baseball-sized to house-sized ice chunks orbiting Saturn
      5. a disk of metallic hydrogen gas.

    60. Most of Saturn is made most likely of:
      1. iron and nickel
      2. carbonous compounds
      3. hydrogen
      4. ices (methane, water, ammonia)
      5. silicates

    61. Many of the gaps seen in the rings of Saturn are caused by
      1. collisions with the magnetosphere.
      2. orbital resonances with Saturn's moons.
      3. tidal stripping of ringlets
      4. solar-particle interactions
      5. synchrotron radiation.

    62. The upper atmosphere of Saturn is about _____K.
      1. 0
      2. 10
      3. 100
      4. 273
      5. 670

      Lecture 23

    63. True or False: Neptune in currently farther from the sun than Pluto.

    64. True or False: Neptune was discovered after its position was predicted using perturbation theory and Newton's law of gravity

    65. The rings of Uranus were discovered using
      1. direct observations using telescopes on Earth.
      2. stellar occultation studies to measure the atmospheric structure.
      3. Voyager images of the planet.
      4. perturbation studies of the planet
      5. orbital sequencing of moons

    66. The surface composition of Uranus is similar to
      1. Mercury
      2. Earth
      3. Io
      4. Jupiter
      5. Pluto

    67. The surface temperature of Pluto is about
      1. 0 K
      2. 50 K
      3. 100 K
      4. 275 K
      5. 670 K

    68. The mass of Pluto was measured using
      1. observations of the orbit of Charon.
      2. observations using the Hubble Space Telescope.
      3. radio observations of the planet's rotation.
      4. infrared observation of the planet's rotation.
      5. none of the above.

    69. Which of the following best describes the magnetic field of Uranus
      1. Uranus has no measurable magnetic field.
      2. Uranus has a very weak magnetic field.
      3. Uranus has a strong magnetic field aligned with its rotation axis.
      4. Uranus has a strong magnetic field tilted with respect to its rotation axis.

    70. True or False: Meteor showers and storms occur when the Earth travels across a comet's orbit.

    71. When a comet is MORE than 6 AU's from the sun,
      1. it develops a coma
      2. it develops a dust trail
      3. it is inactive
      4. it begins to rotate rapidly
      5. none of the above.

    72. The disk of Uranus is:
      1. crater covered and very old.
      2. shows evidence of plate tectonics.
      3. a mostly featureless world with no large weather patterns.
      4. has prominent weather patterns including the great dark spot.
      5. has never been seen by any spacecraft.

    73. The rotation of Uranus is
      1. prograde and similar to Earth
      2. retrograde and very slow
      3. tidally locked to the Sun
      4. is prograde, but very rapid
      5. is tilted at an inclination from the ecliptic of just over 90 degrees.

    74. Neither Neptune nor Uranus was known to the ancient astronomers. Uranus was discovered by accident, but Neptune was found by the effects it had on Uranus' orbit.
      1. Correct.
      2. Wrong. The ancient Greeks knew of Uranus
      3. Wrong. The second sentence is correct only if the words Uranus and Neptune are interchanged.
      4. Wrong. The effects on Pluto's orbit were what led to the discovery of Neptune.

    75. The composition of Pluto is most similar to
      1. the Terrestrial planets.
      2. the Jovian planets.
      3. the moons around Uranus.
      4. the Moon of Earth.

    76. Which of the following planets was discovered accidentally in the 1700's
      1. Mercury
      2. Jupiter
      3. Uranus
      4. Neptune
      5. Pluto

      Lecture 24

    77. True or False: Asteroids are always found orbiting between Mars and Jupiter.

    78. Comets spend most of their time
      1. in the Oort cloud.
      2. in the Kirkwood gaps.
      3. in the inner solar system.
      4. near the orbit of Jupiter
      5. none of the above.

    79. The dust tails of comets point
      1. toward the sun
      2. away from the sun
      3. toward the Earth
      4. toward Jupiter
      5. toward their directions of travel

    80. Tails of comets are
      1. caused by ionization of the Earth's atmosphere as the comet enters it
      2. dust an gas captured by the comet
      3. the jet exhausts of the engines that make the comets move
      4. dust and gas blown off the comet by the solar wind and radiation pressure
      5. misleading: Comets do not have trails.

    81. Most meteors are
      1. small bits of debris scattered from comets
      2. small comets that never had long tails
      3. pieces of Jupiter
      4. pieces of Saturn
      5. none of these

    82. True or False: Meteors have never struck a human being in recorded history.

    83. A comet's coma is about
      1. the same size as it's nucleus
      2. a hundred times larger than its nucleus
      3. ten thousand times larger than its nucleus
      4. a million times larger than its nucleus
      5. a billion times larger than its nucleus

    84. During a meteor shower,
      1. most of the meteors seen will tend to originate from the same point on the celestial sphere
      2. many large meteors will strike the Earth's surface.
      3. Hundreds of thousands of meteors per hour will normally be seen..
      4. all of the above

    85. True or False: Comets develop a coma and tail when the ices in the comet's nucleus begin to sublimate in the inner solar system.

    86. Meteorites
      1. have not struck Earth since the dinosaurs were killed (65 million years ago).
      2. have never struck a human being
      3. are usually found in Antarctica
      4. have killed over 3 million reindeer
      5. are found by the millions all over Earth.

    87. Large scale damage (equivalent to 1 megaton of TNT) from meteors is likely to happen on Earth about:
      1. every few days
      2. several times a year
      3. every few years
      4. every few decades to few hundred years.
      5. every 10,000 years.

    88. Most meteors are
      1. small bits of debris scattered from comets
      2. small comets that never had long tails
      3. pieces of Jupiter
      4. pieces of Saturn
      5. none of these

    89. The number of meteors seen per hour in a meteor shower can vary from year to year due to
      1. the rapidly changing speed of the Earth in its orbit.
      2. the Poynting-Robertson effect.
      3. the material from the originating comet may not be evenly distributed in its orbit.
      4. trick question: meteor showers do not significantly change their intensity from year to year.