Deck 13: Comparative Planetology of the Terrestrial Planets

Question 1

Which of these gases is most responsible for the greenhouse effect on Earth?

A) nitrogen (N₂)
B) carbon dioxide (CO₂)
C) ozone (O₃)
D) ammonia (NH₃)

Answer 1

carbon dioxide (CO₂)

Question 2

Which of the following objects has a temperature that is closest to the temperature of Earth's core?

A) the surface of Venus
B) the core of Mars
C) the surface of the Sun
D) the core of the Sun

Answer 2

the surface of the Sun

Question 3

Which of the following are the youngest parts of the Earth's crust?

A) the bottom layer of the Grand Canyon
B) the continental margins
C) the pre-Cambrian shield
D) the mid-ocean rises

Answer 3

the mid-ocean rises

Question 4

Which of the following describes the process responsible for gradual changes in position and orientation of the Earth's continental plates?

A) continental shift
B) continental drift
C) continental rifting
D) continental effect

Question 5

What does the presence of Earth's magnetic field tell us about Earth's interior?

A) The core must be very hot and dense.
B) It must contain a conductive liquid.
C) It must contain metallic hydrogen.
D) The mantle must be liquid.

Question 6

How would Earth's atmosphere be different today if Earth contained no liquid water?

A) It would have more nitrogen.
B) It would have more oxygen.
C) It would have more carbon dioxide.
D) It would be as thin as Mars's atmosphere.

Question 7

Why must the central regions of the Earth's core be solid?

A) The pressure at the centre raises the melting point.
B) The magnetic field cannot penetrate into the centre of the core.
C) Convection does not extend all the way to the centre of the core.
D) The Earth initially formed from solid particles in the solar nebula.

Question 8

Which of the following maintains the supply of oxygen in the Earth's atmosphere?

A) stars in the Milky Way
B) the solar wind
C) plant life
D) meteorites

Question 9

Which of these gases are most abundant in the Earth's atmosphere today?

A) nitrogen and oxygen
B) argon and oxygen
C) hydrogen and oxygen
D) methane and oxygen

Question 10

Which of these gases were present in the Earth's first atmosphere?

A) methane and oxygen
B) nitrogen and oxygen
C) hydrogen and methane
D) hydrogen and oxygen

Question 11

Where does the molten rock that emerges from volcanoes come from?

A) the solid core
B) the molten core
C) the upper mantle
D) the upper crust

Question 12

The Himalayan Mountains are rugged, jagged peaks, while the Appalachians are smooth and rolling. Why is there a difference?

A) The Himalayas are much older and the rocks have begun breaking off.
B) The Himalayas are volcanic mountains and the Appalachians are not.
C) The Appalachians are much older and have been smoothed by erosion.
D) The Appalachians are younger and have just started to be thrust upward by plate tectonics.

Question 13

Which of the following is/are produced by plate tectonics?

A) ocean currents
B) rift valleys
C) aurora borealis
D) the Earth's magnetic field

Question 14

Which two planets do NOT rotate on their axes clockwise as seen from the north?

A) Mercury and Venus
B) Venus and Uranus
C) Venus and Neptune
D) Uranus and Neptune

Question 15

Why does the greenhouse effect occur on Earth?

A) because carbon dioxide is transparent to visible light and opaque to infrared radiation
B) because carbon dioxide is opaque to visible light and transparent to infrared radiation
C) because carbon dioxide is totally opaque to both visible light and infrared radiation
D) because carbon dioxide is totally transparent to both visible light and infrared radiation

Question 16

The Earth's magnetic field is generated by the dynamo effect. Where does this take place?

A) in the aurora borealis and aurora australis
B) in the solid central core
C) in the plastic mantle
D) in the molten metallic core

Question 17

How does the greenhouse effect produce excess heat in a planet's atmosphere?

A) by trapping infrared radiation and preventing it from escaping into space
B) by clouds blocking the surface so it doesn't receive any infrared radiation
C) by trapping light gases and preventing them from escaping into space
D) by trapping ultraviolet light in the upper atmosphere of the planet

Question 18

Which of the following solar system objects is most similar to Mercury in size and appearance?

A) Mars
B) Phobos
C) Earth's moon
D) Venus

Question 19

Which of the following is the longest?

A) the revolution period of Earth
B) the rotation period of Earth
C) the revolution period of Mars
D) the rotation period of Mars

Question 20

Which of the following, if found on Mars, would support the idea that the Martian crust is divided into moving plates like those on Earth?

A) giant impact basins
B) the most massive volcanoes in the solar system
C) dry river beds and sea floors
D) folded mountain chains

Question 21

Why is the Moon no longer geologically active?

A) because it is rotating too slowly
B) because its radioactive elements were never abundant
C) because its interior has cooled
D) because it does not have water on its surface

Question 22

How does the fission hypothesis describe the Moon's origin?

A) The Moon broke off from a rapidly spinning proto-Earth.
B) The Earth and the Moon formed from the same cloud of matter.
C) The Moon formed elsewhere in the solar nebula and was later captured by the Earth.
D) The Moon was formed when a very massive planetesimal smashed into the young Earth.

Question 23

Which of the following is one of the stages in the development of a terrestrial planet?

A) hydrogenation
B) differentiation
C) convection
D) radiation

Question 24

Why would a decrease in the density of the ozone layer create a public health concern?

A) The greenhouse effect would not be as efficient and the temperature of the Earth would fall.
B) The greenhouse effect would be more efficient and the temperature of the Earth would rise.
C) Plant life would no longer have the ozone it needs for photosynthesis to create chlorophyll.
D) Additional ultraviolet radiation from the Sun would reach the surface of the Earth.

Question 25

What causes slow surface evolution?

A) accretion
B) differentiation
C) plate tectonics
D) cratering

Question 26

Which of the following pieces of evidence supports the large-impact hypothesis?

A) The rock on the highlands formed from molten material.
B) The maria are impact basins that flooded with lava.
C) The oldest rocks on the Moon are over 4 billion years old.
D) Earth and the Moon have almost the same density.

Question 27

In the development of a terrestrial planet, at what stage does molten rock flow through fissures and fill deep basins?

A) differentiation
B) cratering
C) slow surface evolution
D) giant basin formation

Question 28

Which hypothesis concerning the formation of the Moon makes predictions that best fit the observed lunar data?

A) the large-impact hypothesis
B) the fission hypothesis
C) the capture hypothesis
D) the condensation hypothesis

Question 29

Which of the following is evidence that the Earth went through a process of differentiation?

A) It rotates slowly.
B) Its magnetic field has changed over time.
C) Its average density is higher than the density of the crust.
D) It has a surface that is 75% water.

Question 30

What is the only form of slow surface evolution on the Moon?

A) low density masses of rock rising from the interior
B) moonquakes disturbing the surface features
C) low level meteorite impacts
D) motion along a network of small faults

Question 31

According to the large-impact hypothesis, why does the Moon have a low density?

A) Earth and its impactor had already differentiated.
B) The impactor did not have a large enough mass to differentiate.
C) The impactor formed in the outer solar system.
D) After the impact, the high-density material fell back to Earth.

Question 32

How would the Moon's appearance change if the side that always faces Earth had a thicker crust than the side that always faces away?

A) It would have more maria.
B) It would be brighter, with a lower albedo.
C) It would have more impact craters.
D) It would have more multiringed basins.

Question 33

In the development of a terrestrial planet, at what stage does dense material settle to the core and less dense material to the outer parts?

A) differentiation
B) slow surface evolution
C) accretion
D) giant basin formation

Question 34

What are the lunar maria?

A) the lava plains of the lunar lowlands
B) the smooth plateaus of the lunar highlands
C) groups of small craters on the far side
D) moving plates of lunar crust

Question 35

How does the condensation hypothesis describe the Moon's origin?

A) The Moon broke off from a rapidly spinning Earth.
B) The Earth and the Moon formed from the same cloud of matter.
C) The Moon formed elsewhere in the solar nebula and was later captured by the Earth.
D) The Moon was formed when a very massive planetesimal smashed into the young Earth.

Question 36

What does the presence of breccias among the lunar rock samples show?

A) that volcanism never occurred on the Moon
B) that molten lava once flowed over the lunar surface
C) that water once existed on the Moon in the form of small lakes and streams
D) that the lunar surface was fragmented by meteorite impacts

Question 37

Which of the following would explain the fact that the Moon does not have a magnetic field?

A) The Moon is spinning too slowly to produce a magnetic field.
B) The interior of the Moon is too hot to produce a magnetic field.
C) The crust of the Moon is so thick that the magnetic field does not reach beyond the interior.
D) The Moon's core contains little if any molten iron.

Question 38

What does the presence of vesicular basalts - rocks containing frozen-in remnants of gas bubbles - among the lunar rock samples show?

A) that the lunar surface was fragmented by meteorite impacts
B) that the crust must have been made of anorthosite
C) that molten lava once flowed over the lunar surface
D) that the Moon was once hit by a very large meteorite

Question 39

How does the large-impact hypothesis describe the Moon's origin?

A) The Moon broke off from a rapidly spinning Earth.
B) The Earth and the Moon formed from the same cloud of matter.
C) The Moon formed elsewhere in the solar nebula and was later captured by the Earth.
D) The Moon was formed when a very massive planetesimal smashed into the young Earth.

Question 40

The Earth possesses few visible craters, and the Moon possesses many. Why is this?

A) because the Earth formed later than the Moon and therefore hasn't encountered as many meteoroids
B) because the Moon's location in space makes it more likely to be hit by meteoroids
C) because erosion and plate tectonics have removed evidence of past cratering on the Earth
D) because the Earth has a higher average density than the Moon

Question 41

The graph plots the escape velocity of several solar system objects along the vertical axis, and surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the objects plotted in this diagram has the highest escape velocity?

A) Mars
B) the Moon
C) Venus
D) Earth

Question 42

What is the evidence that Mercury has a large iron core?

A) the large lobate scarps
B) the planet's high mean density
C) the lava flows near Caloris Basin
D) iron emission lines in its spectrum

Question 43

Which of the solar system objects listed below is most similar to the Earth in terms of mass and density?

A) Mercury
B) the Moon
C) Venus
D) Mars

Question 44

Which forms of radiation are able to pass through the ozone layer?

A) ultraviolet, visible light, infrared
B) infrared only
C) visible light only
D) visible light and infrared only

Question 45

Why is the greenhouse effect so much stronger on Venus than on Earth?

A) The atmosphere of Venus contains free oxygen.
B) The atmosphere of Venus is predominantly composed of carbon dioxide.
C) The surface of Venus converts infrared into visible radiation.
D) Venus has no active volcanoes to emit dust that could cool the planet.

Question 46

How has the surface of Venus been studied?

A) using radar maps made from Earth
B) using radar maps made from satellites orbiting Venus
C) using wheeled rovers that have landed on the surface of Venus
D) using visible-light cameras on satellites orbiting Venus

Question 47

Which of the following has the least effect on the speed at which a planet loses its atmosphere?

A) escape velocity (determined by mass and radius)
B) temperature
C) rotation period
D) atmospheric composition

Question 48

Which sequence below shows the terrestrial worlds in the correct order from youngest to oldest average surface age?

A) Moon, Mars, Venus, Earth
B) Earth, Mars, Venus, Moon
C) Venus, Earth, Moon, Mars
D) Mars, Earth, Venus, Moon

Question 49

Which of the following properties differs least between the Earth and Venus?

A) atmospheric density
B) surface temperature
C) atmospheric composition
D) fraction of basaltic lowlands

Question 50

Which of the following is one hypothesis that has been suggested to explain the uniform age of the surface of Venus?

A) The surface of Venus is made of rocks that are much harder than the Earth's and thus last longer.
B) Venus' entire crust periodically breaks up, sinks, and is replaced when lava flows cool.
C) The clouds in the atmosphere of Venus protect it from meteorites so that very few impacts occur to change its surface.
D) Dust storms deposit large amounts of dust on the surface of Venus, making it appear to be of uniform age.

Question 51

What feature of Mercury is explained by the hypothesis that the planet shrank slightly when it was young?

A) extended lava plains
B) magnetic field
C) long, curved ridges
D) regolith

Question 52

Which of the following planets has the highest atmospheric pressure?

A) Venus
B) Mars
C) Earth
D) Mercury

Question 53

What is a major difference between the Moon's near and far sides?

A) The far side has many fewer craters.
B) The far side has many fewer maria.
C) The far side has many more craters.
D) The far side has many more maria.

Question 54

What is believed to be the cause of coronae on Venus?

A) impact craters
B) plate tectonics
C) rising convection currents in the interior
D) the planet's slow rotation

Question 55

Which of the following planets has the lowest atmospheric pressure?

A) Earth
B) Mars
C) Venus
D) Mercury

Question 56

The graph plots the escape velocity of several solar system objects along the vertical axis, and surface temperature along the horizontal. The lines plotted in the figure are the speeds of the fastest gas particles as a function of temperature for various gases. Which of the gases plotted in the diagram could be retained in the atmosphere of Mars?

A) only CO₂
B) NH₃ and He
C) CO₂, NH₃, and O₂
D) H₂ and He

Question 57

Which of the following processes appears to dominate the geology of Venus?

A) volcanism
B) plate tectonics
C) erosion by flowing water
D) impact cratering

Question 58

Which evidence seems to suggest that Mercury did NOT undergo a large impact?

A) Volatiles were found in Mercury's crust.
B) Mercury has a magnetic field.
C) Mercury has a very dense core.
D) Mercury is covered with small impact craters.

Question 59

In what way is Venus very different from the Earth?

A) radius
B) mass
C) density
D) surface temperature

Question 60

The graph plots the escape velocity of several solar system objects along the vertical axis, and surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the objects plotted in this diagram is least able to hold an atmosphere?

A) Mars
B) the Moon
C) Mercury
D) Venus

Question 61

How are the northern and southern hemispheres of Mars different?

A) The northern hemisphere is much younger.
B) The northern hemisphere is much higher.
C) The southern hemisphere is more volcanic.
D) Only the southern hemisphere has a polar cap.

Question 62

What does the extremely large size of volcanoes on Mars indicate?

A) Mars has a much thicker crust than the Earth.
B) Water once flowed in streams on Mars.
C) Mars has never had a molten interior.
D) Erosion does not occur on Mars.

Question 63

What is believed to be the origin of the moons of Mars?

A) They formed when a body the size of the Earth impacted with Mars early in its history.
B) They formed from material ejected from Olympus Mons and other large volcanoes on Mars.
C) They are escaped moons of Saturn.
D) They are captured asteroids.

Question 64

Besides the Earth, which of the terrestrial planets and/or satellites of terrestrial planets shows evidence for the possible existence of liquid water flowing on its surface in the past?

A) Venus
B) the Moon
C) Phobos
D) Mars

Question 65

The graph plots the escape velocity of several solar system objects along the vertical axis, and surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the objects plotted in this diagram has the lowest escape velocity?

A) the Moon
B) Mars
C) Venus
D) Earth

Question 66

Most terrestrial planets have portions of their surface that appear to be significantly older than other portions of their surface. What evidence suggests that the surface of Venus is all about the same age?

A) Photos taken by probes that landed on Venus showed that all of the rocks were of the same age.
B) The craters on Venus are randomly distributed in size and number across the surface.
C) The volcanoes on Venus are not found in isolated groups, but are scattered around the planet.
D) The thick atmosphere of Venus has prevented erosion from taking place.

Question 67

The separation between Africa and Arabia is a(n) ____________________ valley.

Question 68

What is the dominant reason why Mars has a much thinner atmosphere than Earth?

A) Mars has a smaller escape velocity.
B) The early oceans of Mars removed more carbon dioxide.
C) Mars outgassed much less carbon dioxide due to its small size.
D) Mars stores much more carbon dioxide in its polar ice caps.

Question 69

Which of the following is suggested by the flow patterns found on the surface of Mars and the number of craters on top of them?

A) Volcanism is occurring on Mars.
B) Mars is a planet rich in liquid water in the present day.
C) The climate on Mars was different billions of years ago.
D) The polar caps are made of liquid water.

Question 70

Which of the answers below orders the terrestrial planets from highest to lowest atmospheric pressure at the surface?

A) Venus, Mercury, Mars, Earth
B) Venus, Earth, Mars, Mercury
C) Earth, Mars, Venus, Mercury
D) Earth, Venus, Mars, Mercury

Question 71

Mars has sufficient mass and a low enough temperature that water molecules could exist in its atmosphere as vapour. Why does the atmosphere of Mars contain little or no water vapour?

A) Mars formed in a part of the solar nebula that lacked oxygen.
B) Mars formed in a part of the solar nebula that lacked hydrogen.
C) Ultraviolet radiation breaks water molecules into less massive particles that can escape.
D) Water molecules combine readily with chlorine to form hydrochloric acid.

Question 72

____________________ is responsible for absorbing ultraviolet radiation in the Earth's upper atmosphere.

Question 73

The smallest terrestrial planet is ____________________.

Question 74

Which of the following is a very long and deep canyon on Mars?

A) Valles Marineris
B) Ishtar Terra
C) Tharsis Bulge
D) Hellas Basin

Question 75

Which of the answers below orders the terrestrial planets from lowest to highest atmospheric pressure at the surface?

A) Mercury, Mars, Earth, Venus
B) Mercury, Venus, Earth, Mars
C) Mars, Earth, Venus, Mercury
D) Mars, Mercury, Venus, Earth

Question 76

Based on our current knowledge, how does the crust of Mars compare to that of the Earth?

A) It's much thinner.
B) It contains more water.
C) It's more geologically active.
D) It's much stronger.

Question 77

________________ ________________ is the gas molecule most responsible for the greenhouse effect on both Venus and Earth.

Question 78

Why does Mars no longer have a magnetic field?

A) Its core cooled and the dynamo effect shut off.
B) Giant impacts slowed the planet's rotation.
C) Mars does not have a dense core.
D) The thin atmosphere can't protect the planet from the solar wind.

Question 79

The largest satellite orbiting a terrestrial planet is ____________ _____________.

Question 80

If Mars had active plate tectonics, which of the following would you NOT expect to see on its surface?

A) valley networks
B) very large shield volcanos
C) mountain ranges
D) rift valleys