1. What is the name of the first rover on Mars?
a) Viking 1.
b) Soujourner.
c) Venera 7.
d) Mariner 10.
e) Lowell.

2. Which of the following features are only rarely seen on the surface of the Moon?
a) Craters.
b) Hardened lava flows.
c) Volcanic mountains.
d) Material ejected by a collision.
e) Rilles.

3. The large dark spots one can see on the face of the Moon without a telescope are:
a) very cratered, compared to the rest of the Moon.
b) very mountainous, compared to the rest of the Moon.
c) smooth lava flows.
d) composed of the oldest known rocks in the solar system.
e) about the diameter of the Earth.

4. What is the evidence that some of the outer moons of Jupiter were captured, rather than formed with Jupiter?
a) they are too hot to have formed with Jupiter.
b) they have the same composition as Saturn.
c) they have the same composition as Earth.
d) they have retrograde orbits.
e) they are very large for Moons: larger than Pluto.

5. Which of the following has the FEWEST large volcanic mountains?
a) The Moon.
b) Venus.
c) Earth.
d) Mars.
e) They all have the same amount.

6. Which of the following geological features are found on the surface of Mars, but NOT on Venus?
a) Extinct volcanoes.
b) Large-scale hardened lava flows.
c) Craters.
d) Dry river beds.
e) Liquid water oceans.

7. Observations of Venus in visible light using the Hubble Space Telescope reveal:
a) A very cratered rocky surface.
b) A dark, smooth surface with few mountain ranges.
c) Polar ice caps and evidence of huge dust storms.
d) A completely cloud-shrouded planet.
e) Extremely large volcanic mountains.

8. The light-colored polar caps on Mars are most likely made up of:
a) Sulfur dioxide, and other sulfur compounds.
b) Volcanic outflow of light-colored lava and dust.
c) Water and carbon dioxide ices.
d) Light-colored dust, blown there by intense dust storms.
e) Organic molecules.

9. The Soujourner Rover:
a) Discovered bacteria in rocks on Mars.
b) Explored the surface of Venus for about 3 months.
c) Was the first rover on Mars.
d) Was the first spacecraft to send back pictures of Mars.
e) Reached Mars in 1976.

10. Which of the following objects is most likely to have a liquid water ocean under its surface?
a) Venus.
b) Io.
c) Europa.
d) Callisto.
e) Phobos.

11. According to most scientists, the Moon probably formed:
a) from a collision of a large planetesimal with the Earth.
b) from the Earth cracking and breaking apart into two pieces.
c) elsewhere in the solar system, and was gravitationally captured.
d) simultaneously with the Earth, as a "double planet".
e) there is no evidence for any of the above scenarios.

12. Which planets or moons show evidence of water erosion?
a) Earth and the Moon.
b) Earth and Venus.
c) Earth and Mars.
d) Venus, Earth, and Mars.
e) All of the terrestrial planets.

13. Which of the following moons has the youngest surface?
a) Phobos.
b) Callisto.
c) Ganymede.
d) Europa.
e) Io.

14. The surface of Io has many:
a) tall volcanic mountains.
b) craters.
c) cracks in the ice.
d) lava flows.
e) dry river beds.

15. On the Moon, the maria are mostly only seen on the:
a) highlands.
b) far side.
c) dark side.
d) southern hemisphere.
e) near side.

16. The long cliff-like structures seen on Mercury are called:
a) scarfs.
b) scarps.
c) bluffs.
d) biffs.
e) oscars.

17. Which of the following is true about Venus?
a) The Viking spacecraft landed there.
b) The Sojourner rover explored its surface.
c) It is covered with frost made in part of dry ice.
d) It has thick clouds made mainly of sulfuric acid.
e) It has thick clouds made mainly of H₂O.

18. Which planet or moon did the Venera spacecraft visit?
a) Mercury.
b) Venus.
c) The Moon.
d) Mars.
e) Jupiter.

19. On which planet or moon are large (possibly) extinct volcanoes found, with large-scale lava flows?
a) Mercury.
b) Venus.
c) The Moon.
d) Mars.
e) Mars and Venus.

20. Which of the following planets has the oldest surface?
a) Mercury.
b) Venus.
c) Mars.
d) Earth.
e) They all have the same age.

21. Which planet(s) have polar ice caps?
a) Mercury, Venus, Earth, and Mars.
b) Venus and Earth.
c) Earth and Mars.
d) Mercury and Earth.
e) Only Earth.

22. On which planet or moon is the Valles Marineris?
a) Mercury.
b) Venus.
c) The Moon.
d) Mars.
e) Phobos.

23. The appearance of Io best resembles:
a) A pizza.
b) A golf ball.
c) A quilt.
d) A cueball.
e) Humpty Dumpty.

24. Which of the following rovers drove the furthest on the surface of Mars so far?
a) Soujourner.
b) Viking 1.
c) Viking 2.
d) Opportunity.
e) Venera.

25. One of the goals of the Messenger mission was to:
a) obtain close-up pictures of Mercury.
b) bring back soil and rocks from Mars.
c) use radar to test whether Europa has liquid water under the icy surface.
d) investigate the magnetic field of Jupiter.
e) take close-up pictures of Pluto.

26. Jupiter's two main chemical constituents are:
a) H₂ and He.
b) H₂ and C.
c) N₂ and O₂.
d) CH₄ and NH₃.
e) CO₂ and H₂SO₄.

27. Our best views of the surface of Mercury were obtained:
a) By the Magellan spacecraft, using radar mapping.
b) By the Galileo spacecraft.
c) By the Voyager 2 spacecraft.
d) By the Mariner 10 and Messenger spacecraft.
e) By the Hubble Space Telescope.

28. Phobos is:
a) spherical.
b) a dwarf planet, according to the new definition from the IAU.
c) a moon of Venus.
d) a moon of Jupiter.
e) very cratered.

29. The core of Venus is likely made of:
a) liquid metallic hydrogen.
b) water.
c) iron.
d) aluminum.
e) rock.

30. Which of the following spacecraft is/are currently orbiting Mars and sending back data?
a) The Magellan spacecraft.
b) The Galileo spacecraft.
c) The Messenger spacecraft.
d) The 2001 Mars Odyssey, Mars Express, ExoMars Trace Gas Orbiter, the Mars Reconnaisance Orbiter, the MAVEN satellite, and the Mars Orbiter Mission (Mangalyaan).
e) The Viking spacecraft.

31. The highlands on the Moon:
a) are darker in color than the maria.
b) are more cratered than the maria.
c) are younger than the maria.
d) were caused by plate tectonics.
e) were caused by hot spot volcanism.

32. The Moon rocks brought back to Earth by the Apollo astronauts:
a) are between one million and 500 million years old.
b) are between 2 and 3 billion years old.
c) are between 3.1 and 4.4 billion years old.
d) are about 10 billion years old.
e) are the oldest rocks known in the solar system.

33. The Moon has many more craters than the Earth. This is because:
a) The Moon protected the Earth from impacts: most of the large objects hit the moon rather than the Earth.
b) The Earth's atmosphere stopped all the potentially damaging objects.
c) The Moon was much more volcanic than the Earth in the past, and these volcanoes caused the craters on the Moon.
d) Plate tectonics has returned cratered surface layers to the Earth's interior and weathering has obliterated more recent craters on the Earth.
e) Sheer luck: just by chance the Earth hasn't been hit by as many objects as the Moon.

34. Which planets have liquid metallic hydrogen in their interiors?
a) Only Jupiter.
b) Jupiter and Saturn only.
c) Neptune and Uranus only.
d) All of the Jovian planets.
e) Only the Earth and Venus.

35. The Jovian planets:
a) are gaseous throughout.
b) are mainly liquid, with thick atmospheres and a rock core.
c) do not have solid cores: they are only liquid and gas.
d) are mostly solid, with a thick atmosphere but little liquid.
e) they are 99 percent gaseous, with a small rocky core.

36. The Great Red Spot:
a) Was seen by Galileo.
b) Is a giant storm in the atmosphere of Jupiter.
c) Is twice the diameter of the Earth.
d) Has lasted hundreds of years.
e) All of the above.

37. Which of the following objects has the highest density?
a) The Moon.
b) Callisto.
c) Earth.
d) Ganymede.
e) Pluto.

38. Which of the following objects has an atmosphere which is mainly nitrogen and methane?
a) Io.
b) Callisto.
c) Europa.
d) Ganymede.
e) Titan.

39. Which of the following spacecraft visited Mercury?
a) Global Surveyor.
b) Cassini.
c) Voyager 2.
d) Galileo.
e) Messenger.

40. Neptune is blue because:
a) it is covered with a thick layer of ice.
b) it has thick clouds of sulfuric acid, which appear blue.
c) it has a lot of ammonia in its atmosphere, which absorbs red light and scatters blue light.
d) it has a lot of methane in its atmosphere, which absorbs red light and scatters blue light.
e) scientists have no idea why Neptune is blue.

41. The Great Dark Spot is:
a) a giant storm in the atmosphere of Jupiter.
b) a giant storm in the atmosphere of Neptune.
c) a giant impact crater on Callisto.
d) a giant impact crater on Mercury.
e) a giant impact crater on the Moon.

42. The large circular cracks seen on the surface of Venus are called:
a) scarps.
b) corona.
c) rilles.
d) maria.
e) belts.

43. Which of the following moons has the fewest craters?
a) Phobos.
b) Callisto.
c) Europa.
d) Ganymede.
e) Io.

44. On which of the following objects have we landed spacecraft, but NOT explored via a rover?
a) The Moon.
b) Mercury.
c) Venus.
d) Mars.
e) Europa.

45. Which process contributes the most to making Io volcanic?
a) Heat left over from its formation is seeping up from the center.
b) Meteoroids hitting Io crack the surface, causing liquid to flow onto the surface.
c) Tidal forces from Jupiter and Europa heat its interior.
d) Tidal forces from Saturn heat its interior.
e) Scientists have no idea why Io is volcanic.

46. The term ' the belts and zones of Jupiter' refers to:
a) the faint dark rings orbiting Jupiter which were discovered by the Voyager spacecraft.
b) the asteroids orbiting the Sun in the orbit of Jupiter.
c) the stripes on Jupiter.
d) the liquid layers inside of Jupiter.
e) the closest distance a moon can get to Jupiter, before being torn apart by tidal forces.

47. The tallest mountain in the solar system is on:
a) Mercury.
b) Venus.
c) Earth.
d) Mars.
e) Io.

48. The appearance of Europa best resembles:
a) A pizza.
b) A cue ball.
c) Callisto.
d) The Moon.
e) Mars.

49. The magnetic field of Jupiter is caused by:
a) The solid inner core of Jupiter, which is a strong magnet.
b) the rotation of Jupiter creating an electric current in the liquid iron outer core of Jupiter.
c) the rotation of Jupiter creating an electric current in the liquid water interior of Jupiter.
d) the rotation of Jupiter creating an electric current in the liquid metallic hydrogen layer in Jupiter.
e) Jupiter does not have a magnetic field.

50. What is the name of rover currently operating on Mars?
a) Viking 2.
b) Venera 2.
c) Curiosity.
d) Messenger.
e) Sojourner.

51. Which of the following is NOT a consequence of plate tectonics?
a) The maria on the Moon.
b) The large trench on the western coast of South America.
c) The Mid-Atlantic Ridge.
d) The lack of craters on the Earth's surface.
e) The Himalayan mountains.

52. A Jovian planet is one that resembles:
a) Earth.
b) Jupiter.
c) The Galilean Moons.
d) Pluto.
e) An asteroid.

53. Caloris Basin is:
a) A gigantic impact basin on Venus.
b) A gigantic crack in the surface of Mars.
c) A huge impact basin on Mercury.
d) A very prominent crater on the Moon.
e) A very large depression on Venus.

54. Which of the following spacecraft landed on Mars?
a) Messenger.
b) Venera.
c) Viking.
d) Voyager.
e) New Horizons.

55. Where is Olympus Mons?
a) On Mercury.
b) On Venus.
c) On Mars.
d) On Miranda.
e) On Callisto.

56. Pancake domes are found:
a) On Mercury.
b) On Venus.
c) On Mars.
d) On Ganymede.
e) On Europa.

57. Which of the following objects has the youngest surface?
a) Mercury.
b) Venus.
c) Callisto.
d) Phobos.
e) The highlands on the Moon.

58. The rilles on the Moon are:
a) large circular cracks, caused by lava uplifting a dome, and the dome then collapsing.
b) the lunar equivalent of the Mid-Atlantic Ridge, where tectonic plates are moving apart.
c) the equivalent of subduction zones: two continental plates colliding.
d) channels caused by streams of lava.
e) the very large dark spots that can be seen from Earth without a telescope.

59. What is the name of the large impact crater on Mercury that faces the Sun (or is directly away from the Sun) when Mercury is at its closest point to the Sun in its orbit?
a) Cassini Basin.
b) Valhalla.
c) the Great Dark Spot.
d) Corona Basin.
e) Caloris Basin.

60. Based on computer models, astronomers theorize that the interior of Uranus is:
a) mostly ice.
b) mostly liquid metallic hydrogen.
c) largely liquid, with a rocky core and a thick atmosphere.
d) mostly iron and nickel, with a rocky mantle.
e) similar to Earth's.

61. Which of the following scenarios for the formation of the Moon is most accepted by astronomers?
a) it formed at the same time as the Earth, as a `double planet'.
b) it formed elsewhere in the solar system, and was gravitationally captured.
c) it broke off from the Earth due to internal stresses.
d) the Earth was hit by a large object, which broke off a chunk which became the Moon. The impacting object then left the solar system.
e) the Earth was hit by a large object, which created a disk around the Earth which then formed into the Moon.

62. The Magellan spacecraft found the following features on the surface of Venus:
a) an extremely high density of craters, like the highlands on the Moon.
b) an extremely geologically active, volcanic surface, with many on-going eruptions and molten lava flows.
c) a cracked, icy surface, that may have liquid water under the ice.
d) large (probably) extinct volcanos and large-scale hardened lava flows.
e) huge cracks in the surface, like the Mid-Atlantic Ridge, indicating significant on-going plate tectonics.

63. Which of the following objects has an thin atmosphere made up of mostly sulfur dioxide, SO₂?
a) Europa.
b) Callisto.
c) Io.
d) The Moon.
e) Mars.

64. What is the name of the huge crack in the surface of Mars, 3000 miles long?
a) Cassini Canyon.
b) Valhalla Chasm.
c) Olympus Valley.
d) Caloris Chasm.
e) Valles Marineris.

65. Which of the Galilean Moons has the largest density?
a) Io.
b) Europa.
c) Ganymede.
d) Callisto.
e) They all have the same density.

66. Phobos is a moon of:
a) Mars.
b) Jupiter.
c) Saturn.
d) Uranus.
e) Neptune.

67. The `Continent' of Aphrodite is on:
a) Mercury.
b) Venus.
c) Earth.
d) Mars.
e) Jupiter.

68. Which of the following objects has the largest proportion of methane in its atmosphere?
a) Neptune.
b) Saturn.
c) Jupiter.
d) All of the above have the same proportion of methane.
e) None of the planets or moons have any methane in its atmosphere; all of the methane in our solar system is frozen solid.

69. Why does the sky look pinkish on Mars?

a) Methane in its atmosphere absorbs blue sunlight.
b) CO₂ in its atmosphere absorbs blue sunlight.
c) Thick sulfuric acid clouds absorb blue sunlight.
d) Iron-rich dust particles are suspended in the atmosphere.
e) The atmosphere is redshifted.

70. The fact that most moons always show their same face to their planets is:
a) Very surprising and a great mystery.
b) A natural consequence of the fact that the solar system formed out of a flattened spinning disk of gas and dust.
c) Explained by the law of conservation of angular momentum.
d) A natural consequence of tidal forces acting on the moons.
e) A result of the fact that the moons once had atmospheres.

71. The volcanism on the island of Hawaii is caused by:
a) a `hot spot' in the mantle underneath.
b) two continental plates pulling apart in the middle of the Pacific Ocean, causing lava to flow up in the gap.
c) two continental plates colliding, triggering volcanic activity.
d) a crack in the surface of the Earth, caused by a giant meteor impact.
e) heating of the ocean floor by the Greenhouse Effect.

72. Hot spot volcanism:
a) was responsible for the Mid-Atlantic Ridge.
b) was responsible for the Hawaiian Islands.
c) was responsible for the Andes Mountains.
d) was responsible for the deep sea trench off of the western coast of South America.
e) was responsible for the Appalachian Mountains.

73. The rocks on the floor of the Atlantic Ocean:
a) are all about the same age.
b) increase in age with increasing distance from the Mid-Atlantic Ridge.
c) decrease in age with increasing distance from the Mid-Atlantic Ridge.
d) all have magnetic fields pointing in the same direction.
e) have never been dated.

74. The Earth's magnetic field protects us from:
a) harmful ultraviolet photons from the Sun.
b) freezing to death: it helps keep us warm.
c) meteoroids: chunks of rocks from space that might hit the Earth.
d) the Greenhouse Effect.
e) the solar wind.

75. Which of the following geological features were caused by two tectonic plates colliding head-on?
a) The Andes Mountains and the deep sea trench along the western coast of South America.
b) The Hawaiian Islands.
c) The Mid-Atlantic Ridge.
d) All of the above.
e) None of the above.

76. At the Mid-Atlantic Ridge:
a) Two continental plates are moving apart.
b) Two continental plates are colliding.
c) Two continental plates are sliding past each other, one moving north and the other south.
d) A single isolated hot spot in the mantle has created the entire Mid-Atlantic Ridge.
e) A subduction zone is present.

77. The unstable isotope uranium-235 will spontaneously decay to lead-207, with a half-life of 700 million years. This means that in a time of 1.4 billion years:
a) All of the original uranium-235 in a sample will have decayed.
b) Half of the original uranium-235 will have decayed.
c) 3/4ths of the original uranium-235 will have decayed.
d) 1/4th of the original uranium-235 will have decayed.
e) 7/8th of the original uranium-235 will have decayed.

78. What is the main process responsible for the formation of the Andes Mountains?
a) The Van Allen Belts interacting with the ionosphere.
b) The impact of a very large asteroid.
c) Sea Floor Spreading.
d) Two tectonic plates colliding.
e) Hot spot volcanism.

79. The asthenosphere of the Earth is:
a) the upper level of the atmosphere, also called the ionosphere.
b) the liquid outer core of the Earth.
c) a large region around the Earth containing numerous charged particles; also called the Van Allen Belts.
d) the lowest layer of the atmosphere, where weather occurs.
e) the semi-molten upper mantle of the Earth, responsible for plate tectonics.

80. Regions where two continental plates are colliding, and one gets pulled under the surface, are called:
a) Diffraction zones.
b) Subduction zones.
c) Coriolis regions.
d) Van Allen Belts.
e) Hot spot zones.

81. Which of the following objects has the least impact craters?
a) Europa.
b) Callisto.
c) The highlands of the Moon.
d) Mercury.
e) Ganymede.

82. The large circular cracks on the surface of Venus are called:
a) Maria.
b) Subduction zones.
c) Corona.
d) Scarps.
e) Rilles.

83. Liquid metallic hydrogen is likely present in large amounts in the interiors of:
a) The Moon, Mercury, Mars, Venus, and Earth.
b) Venus and Earth.
c) Europa and Ganymede.
d) Jupiter and Saturn.
e) Jupiter, Saturn, Uranus, and Neptune.

84. What surface features are seen on Io?
a) Many impact craters.
b) Lava flows.
c) Lakes of liquid metallic hydrogen.
d) Very tall extinct volcanoes.
e) Channels of running water.

85. What features are *NOT* seen on the surface of Venus?
a) Impact craters.
b) Extinct volcanoes.
c) Corona.
d) Pancake domes.
e) Large-scale subduction zones and locations of sea-floor spreading.

86. The gigantic storm known as the Great Dark Spot was seen by the Voyager 2 spacecraft on which planet or Moon?
a) Mars.
b) Europa.
c) Neptune.
d) Venus.
e) Saturn.

87. Europa:
a) has a very cratered icy surface.
b) is sometimes called the `Pizza Pie Moon', since it is extremely volcanic, with many volcanic vents.
c) has an atmospheric pressure at its surface greater than Earth's.
d) may have an ocean of liquid water under a cracked icy surface.
e) is the largest Moon in the solar system.

88. The average density of craters on the surface of Ganymede is:
a) greater than Europa, but less than Callisto.
b) greater than both Europa and Callisto.
c) less than both Europa and Callisto.
d) greater than Callisto, but less than Europa.
e) about the same as Europa and Callisto.

89. Which of the following Moons has the highest average density, in grams/cm³?
a) Europa.
b) Ganymede.
c) Io.
d) Callisto.
e) They are all about the same density.

90. The giant impact basin named Caloris Basin is on:
a) Mercury.
b) Venus.
c) Io.
d) Europa.
e) Callisto.

91. Which of the following objects has the least craters per area on its surface?
a) Mimas.
b) Callisto.
c) Titan.
d) Mercury.
e) Ganymede.

92. Large circular cracks called corona are seen on the surface of:
a) Mimas.
b) Callisto.
c) Neptune.
d) Venus.
e) Europa.

93. The highest mountain in the solar system is found on Mars. What is its name?
a) Valhalla.
b) Loki.
c) Olympus.
d) Asgard.
e) Caloris.

94. What is the most geologically active object in the solar system, in terms of on-going volcanic eruptions?
a) Callisto.
b) Io.
c) Earth.
d) Mars.
e) Ganymede.

95. Which moons have a water ice surface covered with prominent cracks?
a) Europa and Enceladus.
b) Titan and Hyperion.
c) Callisto and Mimas.
d) Phobos and Deimos.
e) The Moon and Phobos.

96. The near and far sides of the Moon have somewhat different surfaces. The far side of the Moon has:
a) Large cracks/rifts in the surface, somewhat similar to the Mid-Atlantic Ridge, likely caused by plate tectonics.
b) Huge extinct volcanic mountains.
c) Much less maria than the near side.
d) A very smooth surface, with very few craters.
e) Dry river beds.

97. The surface of Titan appears to have:
a) Liquid methane lakes.
b) A rocky surface with a large number of craters, like the highlands of the Moon.
c) A surface covered with water ice, with a large number of craters.
d) A cracked surface covered with water ice, similar to the surface of Europa.
e) Lakes of liquid metallic hydrogen.

98. From most cratered to least cratered, what is the order of the Galilean Moons?
a) Ganymede, Europa, Callisto, Io.
b) Callisto, Ganymede, Europa, Io.
c) Ganymede, Europa, Io, Callisto.
d) Callisto, Io, Ganymede, Europa.
e) Io, Europa, Ganymede, Callisto.

99. The surface of Iapetus, one of the intermediate-sized moons of Saturn, has:
a) Liquid methane lakes.
b) A water-ice surface with few craters, with prominent cracks, out of which `jets' of water vapor are ejected into space.
c) One side a dark color and one side light.
d) Dry river beds.
e) Many active volcanos, producing a sulfur-rich atmosphere.

100. Curiosity is the name of:

a) A spacecraft that flew by Pluto.
b) The spacecraft currently in orbit around Saturn.
c) The spacecraft currently in orbit around Mercury.
d) The only spacecraft to have successfully landed on Venus, and send back pictures.
e) A rover on Mars.

101. Which of the following is true about Enceladus?
a) It is covered with large-scale lava flows.
b) It has active geysers.
c) It has many tall extinct volcanoes.
d) It has a higher atmospheric pressure than Earth.
e) It is very cratered all over its surface.

102. Which of the following moons has the youngest surface?
a) Triton.
b) Ganymede.
c) The Earth's Moon.
d) Callisto.
e) Mimas.

103. Titan:
a) Has channels on its surface likely caused by flowing methane.
b) Is the largest moon in the solar system.
c) Is the biggest moon of Neptune.
d) Has an old very cratered surface.
e) Has a large crack in its surface called the Valles Marineris.

104. Which of the following has been discovered on Mars, and is considered evidence that liquid water existed on Mars in the past?

a) Sedimentary rocks.
b) Dry river beds.
b) Minerals formed in standing water.
d) Rounded pebbles.
e) All of the above.

105. Which of the following has the oldest surface?
a) Phobos.
b) Europa.
c) Triton.
d) Enceladus.
e) Titan.

106. For which of the following is there some evidence for active volcanoes today, but the evidence so far is not conclusive?
a) Mercury.
b) Venus.
c) Mimas.
d) Callisto.
e) Ganymede.

107. The Cassini spacecraft orbited:
a) Mercury.
b) Venus.
c) Mars.
d) Saturn.
e) Pluto.

108. Voyager 2 was the only spacecraft to obtain close-up pictures of which of the following moons?
a) Callisto and Ganymede.
b) Ariel and Umbriel.
c) Titan and Rhea.
d) Mimas and Enceladus.
e) Phobos and Deimos.

109. Subduction zones are seen on:
a) Venus.
b) Mimas.
c) Callisto.
d) Mercury.
e) None of the above.

110. As far as its formation history is concerned, Caloris Basin most resembles:
a) The Valles Marineris.
b) Olympus Mons.
c) The Maria on the Moon.
d) The Mid-Atlantic Ridge.
e) The Hawaiian Islands.

111. Which of the following is true about Mimas?
a) It is covered with large-scale lava flows.
b) It has active geysers.
c) It has many tall volcanoes that are currently erupting.
d) It has a higher atmospheric pressure than Earth.
e) It is very cratered.

112. Which of the following has large expanses of "grooved terrain", with parallel ridges of ice?
a) Ganymede.
b) Io.
c) The Earth's Moon.
d) Callisto.
e) Mimas.

113. Triton:
a) is the second largest moon in the solar system.
b) has very few craters.
c) Has a large crater called Caloris Basin.
d) Has a large crater called Valhalla.
e) Has a large crack called the Valles Marineris.

114. Which of the following have been discovered on Venus?

a) Huge cracks in the surface, similar to the Mid-Atlantic Ridge.
b) Dry river beds.
c) Large possibly extinct volcanic mountains.
d) A high density of craters, similar to that on the highlands of the Moon.
e) All of the above.

115. Which of the following has water geysers that contribute to one of Saturn's rings?
a) Hyperion.
b) Iapetus.
c) Tethys.
d) Enceladus.
e) Mimas.

116. Most mountains on the Moon were formed by:
a) Impacts.
b) Tectonic plates colliding together.
c) Tectonic plates pulling apart.
d) Hot spot volcanism.
e) There are no mountains on the Moon.

117. The large heart-shaped feature named Sputnik Planitia seen on Pluto by the New Horizons spacecraft is:
a) Mostly water ice, with few craters.
b) Methane, nitrogen, and CO ice, with few craters.
c) Ancient, very cratered, water ice surface.
d) Ancient, very cratered, rocky surface.
e) Two huge rifts in the surface, similar to the Valles Marineris on Mars.

118. Charon is a moon of:
a) Neptune.
b) Uranus.
c) Pluto.
d) Mars.
e) Saturn.

119. Ariel and Umbriel are moons of:
a) Pluto.
b) Neptune.
c) Saturn.
d) Jupiter.
e) Uranus.

120. The `Hot Cross Bun', a cracked rounded mound likely due to cryovolcanism, is on:
a) Venus.
b) Ganymede.
c) Titan.
d) Mimas.
e) Mars.

121. Which of the following is a Kuiper Belt Object?
a) Ceres.
b) Phobos.
c) Callisto.
d) Pluto.
e) All of the above.

122. As far as their formation process is concerned, the maria on the Moon most resemble:
a) The Valles Marineris.
b) Olympus Mons.
c) Caloris Basin.
d) The Mid-Atlantic Ridge.
e) The Hawaiian Islands.

123. Where in the solar system does liquid metallic hydrogen exit?
a) On the side of Mercury facing the Sun.
b) On the surface of Titan.
c) In the interiors of Jupiter and Saturn.
d) In the cores of all four Jovian planets.
e) In the centers of the terrestrial planets.

124. Which of the following moons is spiraling in towards its planet, and will eventually be torn apart by tidal forces?
a) The Earth's Moon.
b) Titan.
c) Ganymede.
d) Callisto.
e) Triton.

125. Io:
a) Has a very cratered surface.
b) Has a cracked icy surface with few craters.
c) Has an atmospheric pressure at its surface higher than that of Earth.
d) Has numerous active volcanoes.
e) Was discovered by the Cassini spacecraft.

126. Which of Saturn's intermediate-sized moons has a prominent ridge along its equator, perhaps caused by the orbital decay of ring particles?
a) Titan.
b) Mimas.
c) Enceladus.
d) Iapetus.
e) Callisto.

127. The most recent rover sent to Mars is called:
a) Curiosity.
b) Viking.
c) Opportunity.
d) Cassini.
e) Messenger.

128. Based on the density of craters on its surface, the surface of Mars is on average:
a) Older than that of the Earth, but younger than Venus, Mercury, and the Moon.
b) Older than Earth and Venus, younger than Mercury and the Moon.
c) Older than Earth, Venus, and Mercury; younger than the Moon.
d) Older than Earth, Venus, Mercury, and the Moon.
e) Younger than Earth, Venus, Mercury, and the Moon.

129. Possible lakes on the surface of Titan may contain:
a) Liquid nitrogen.
b) Liquid metallic hydrogen.
c) Liquid water.
d) Liquid carbon dioxide.
e) Liquid methane.

130. The Cassini Division is:

a) a gigantic crack in the surface of Mars.
b) a gigantic crater on Callisto.
c) the wavelength that separates ultraviolet from visible light.
d) a gap in the rings of Saturn.
e) the semi-liquid upper mantle of the Earth.

131. Which of the following Martian spacecraft has/had seismic equipment?
a) Curiosity.
b) Opportunity.
c) Mars Express.
d) InSight.
e) All of the above.

132. Based on data from the Mars Express spacecraft, scientists have concluded that:
a) A liquid water lake may exist under the south polar ice cap.
b) Mars probably never had liquid water on its surface.
c) Mars has numerous volcanoes that are currently active, spreading new lava across the surface.
d) Mars currently has on-going plate tectonics and continental drift.
e) Mars currently has a strong global magnetic field, about the same as Earth's.

133. Iapetus:
a) Has active geysers, squirting water vapor into space.
b) Has a water ice surface with almost no craters.
c) Has a large ridge extending partway around its equator.
d) Is a moon of Uranus.
e) Is a moon of Mars.

134. Which of the following moons is/are NOT tidally locked to its/their planet?

a) Phobos and Deimos.
b) Earth's Moon.
c) Charon.
d) Callisto.
e) Styx, Hydra, Nix, and Kerberos.

135. Which of the following spacecraft visited Saturn?
a) Messenger.
b) Magellan.
c) Curiosity.
d) Opportunity.
e) Cassini.

136. Olympus Mons was likely produced by:
a) A giant impact.
b) Tectonic plates pulling apart.
c) Ice on the surface freezing to a solid, expanding to produce this feature.
d) Hot spot volcanism.
e) The planet shrinking, causing the surface to wrinkle.

137. Which of the following objects may have glaciers made of nitrogen ice?
a) Mars.
b) Pluto.
c) Callisto.
d) Io.
e) Phobos.

138. Liquid metallic hydrogen is found:
a) in the outer core of the Earth.
b) in the interior of the Sun.
b) in the interiors of the four Jovian planets.
d) inside Jupiter and Saturn.
e) in lakes on the surface of Titan.

139. Which of the following moons belong to Uranus?
a) Ariel and Umbriel.
b) Tritan.
c) Mimas and Enceladus.
d) Styx, Hydra, Nix, and Kerberos.
e) Callisto and Io.

140. The large highland regions known as Aphrodite and Ishtar are found on:
a) Mars.
b) Ganymede.
c) Titan.
d) Venus.
e) Mercury.

141. June 10, 2018 was the last time we received a signal from which Martian rover?
a) Curiosity.
b) Messenger.
c) Viking.
d) Cassini.
e) Opportunity.

142. The structure of the very narrow F ring of Saturn, just outside the main set of rings, is due to:
a) Mimas.
b) Two small moons on either side of it.
c) Enceladus.
d) Titan.
e) Volcanic activity on Io.

143. `Cantaloupe terrain', consisting of icy ridges but very few craters, is seen on:
a) Mars.
b) Triton.
c) Callisto.
d) Phobos.
e) Mimas.

144. Which of the following moons has a retrograde orbit, orbiting its planet in the opposite direction compared to most moons in the solar system?
a) Tritan
b) Titan.
c) Ganymede.
d) Io.
e) Phobos.

145. Rank the following objects in order, in terms of the number density of craters on its surface, from least cratered to most cratered:
a) Io, Enceladus, Mimas.
b) Io, Mimas, Enceladus.
c) Enceladus, Io, Mimas.
d) Enceladus, Mimas, Io.
e) Mimas, Io, Enceladus.

146. Surface features on Venus were mapped using:
a) Hubble Space Telescope.
b) Radar.
c) X-ray observations.
d) Rovers traveling around on the surface.
e) Visible light photographs from the Messenger spacecraft.

147. Based on the density of craters on its surface, the surface of Venus is on average:
a) Older than that of the Earth, but younger than Mars, Mercury, and the Moon.
b) Older than Earth and Mars, younger than Mercury and the Moon.
c) Older than Earth, Mars, and Mercury; younger than the Moon.
d) Older than Earth, Mars, Mercury, and the Moon.
e) Younger than Earth, Mars, Mercury, and the Moon.

148. In January 2019, the New Horizons spacecraft:
a) Flew by Mercury.
b) Flew by Venus.
c) Flew by a Kuiper Belt Object.
d) Crashed into Saturn.
e) Landed on Titan.

149. Which moon or moons are most likely to have liquid water under a water ice surface?

a) Callisto.
b) Mimas.
c) Phobos.
d) Io.
e) Enceladus and Europa.

Answers: 1b, 2c, 3c, 4d, 5a, 6d, 7d, 8c, 9c, 10c, 11a, 12c, 13e, 14d, 15e, 16b, 17d, 18b, 19e, 20a, 21c, 22d, 23a, 24d, 25a, 26a, 27d, 28e, 29c, 30d, 31b, 32c, 33d, 34b, 35b, 36e, 37c, 38e, 39e, 40d, 41b, 42b, 43e, 44c, 45c, 46c, 47d, 48b, 49d, 50c, 51a, 52b, 53c, 54c, 55c, 56b, 57b, 58d, 59e, 60c, 61e, 62d, 63c, 64e, 65a, 66a, 67b, 68a, 69d, 70d, 71a, 72b, 73b, 74e, 75a, 76a, 77c, 78d, 79e, 80b, 81a, 82c, 83d, 84b, 85e, 86c, 87d, 88a, 89c, 90a, 91c, 92d, 93c, 94b, 95a, 96c, 97a, 98b, 99c, 100e, 101b, 102a, 103a, 104e, 105a, 106b, 107d, 108b, 109e, 110c, 111e, 112a, 113b, 114c, 115d, 116a, 117b, 118c, 119e, 120c, 121d, 122c, 123c, 124e, 125d, 126d, 127a, 128b, 129e, 130d, 131d, 132a, 133c, 134e, 135e, 136d, 137b, 138d, 139a, 140d, 141e, 142b, 143b, 144a, 145a, 146b, 147a, 148c, 149e.