Astronomy Chapter 7

All comets orbit the Sun in the same direction as the planets. a) True b) False

a) True

The more massive planets in the solar system tend to be less dense than the lower mass planets. a) True b) False

a) True

The most metal-rich terrestrial planet is a) Mars. b) the Moon. c) Mercury. d) Earth. e) Venus

c) Mercury.

How does the size of the Sun compare to the size of Earth? a) The Sun is about 3 times larger than Earth. b) The Sun is about 10 times larger than Earth. c) The Sun is about 100 times larger than Earth. d) The Sun is about 1000 times larger than Earth. e) The Sun is about 300,000 times larger than Earth.

c) The Sun is about 100 times larger than Earth

What's unusual about our Moon? a) It's the only moon that orbits a terrestrial planet. b) It's by far the largest moon in the solar system. c) It's surprisingly large relative to the planet it orbits.

c) It's surprisingly large relative to the planet it orbits.

The jovian planets in our solar system are __________________________. a) Pluto and Eris b) Mercury, Venus, Earth, and Mars c) Jupiter, Saturn, Uranus, and Neptune d) Io, Europa, Ganymede, and Callisto

c) Jupiter, Saturn, Uranus, and Neptune

Which of the following planets has the most oxygen in its atmosphere? a) Earth b) Mars c) Venus d) Mercury

a) Earth

Which of the following is not true of Mercury? a) It has been studied closely by more than a dozen NASA spacecraft. b) Mercury has essentially no atmosphere. c) At any given time, about half the planet is colder than Antarctica. d) Its surface is heavily cratered.

a) It has been studied closely by more than a dozen NASA spacecraft.

How does the Sun's mass compare with that of the planets? a) It is a thousand times more massive than all the planets combined. b) It is a thousand times more massive than Earth. c) It is a hundred times more massive than all the planets combined. d) It is a hundred times more massive than Earth. e) It is about as massive as all the planets combined.

a) It is a thousand times more massive than all the planets combined.

Which of the following planets has the coldest nighttime temperature? a) Mercury b) Venus c) Earth d) Mars

a) Mercury

The terrestrial planets in our solar system are ______________________________. a) Mercury, Venus, Earth, and Mars b) Mars, Jupiter, Saturn, Uranus, and Neptune c) Jupiter, Saturn, Uranus, and Neptune d) Pluto and Eris

a) Mercury, Venus, Earth, and Mars

Which of the following statements is not an observed pattern of motion in our solar system? a) Most planets orbit at the same speed. b) All planets orbit the Sun in the same direction. c) Almost all moons orbit their planet in the same direction as the planet's rotation. d) Most planets rotate in the same direction in which they orbit. e) Most planetary orbits lie nearly in the same plane.

a) Most planets orbit at the same speed.

What is the Kuiper belt? a) A region of the solar system that extends almost a fourth of the way to the nearest stars and contains a trillion comets with orbits going in all directions around the Sun. b) A region of the solar system beginning just beyond the orbit of Neptune that contains many icy comets. c) A technical name for the asteroid belt. d) The most prominent ring of Saturn that is visible in photographs.

b) A region of the solar system beginning just beyond the orbit of Neptune that contains many icy comets.

The largest terrestrial planet and jovian planet are, respectively: a) Venus and Jupiter. b) Earth and Jupiter. c) Earth and Saturn.

b) Earth and Jupiter.

Which of the following is a characteristic of a dwarf planet? a) A dwarf planet must be in the Kuiper Belt. b) A dwarf planet cannot have any moons. c) A dwarf planet must be round. d) all of the above

c) A dwarf planet must be round.

Which of the following statements about Pluto is not true? a) Its mass is less than 1% of Earth's mass. b) It has more in common with comets in the Kuiper belt than it does with the jovian planets. c) It is the largest and most massive object that is considered to be a dwarf planet. d) It is orbited by at least five moons.

c) It is the largest and most massive object that is considered to be a dwarf planet.

Which jovian planet does not have rings? a) Neptune b) Uranus c) Jupiter d) All the jovian planets have rings

d) All the jovian planets have rings

The Cassini mission to Saturn consists of ________________. a) A spacecraft that orbits Saturn and a sample return mission that landed on Titan, scooped up a surface sample, and will return it to Earth. b) An orbiter that orbits Saturn and a probe that descended to the surface of Titan. c) A large spacecraft that flew by Saturn on its way to other planets. d) An orbiter that orbits Saturn and a probe that descended into Saturn's atmosphere.

b) An orbiter that orbits Saturn and a probe that descended to the surface of Titan.

Which of the following most clearly distinguishes asteroids and comets from planets? a) Unlike planets, asteroids and comets do not orbit the Sun. b) Asteroids and comets are much smaller than planets. c) Asteroids and comets are made of different materials than any planets. d) Asteroids and comets are only found at much greater distances from the Sun than planets.

b) Asteroids and comets are much smaller than planets.

All the planets in the solar system have at least one moon. a) True b) False

b) False

Which planet has a volcanically active moon? a) Earth b) Jupiter c) Saturn d) Uranus e) Neptune

b) Jupiter

Which planet has the most moons? a) Mercury b) Mars c) Venus d) Earth e) B and D

b) Mars

What is the first spacecraft to fly by Pluto? a) Hubble Space Telescope b) New Horizon c) Galileo orbiter d) Cassini e) Curiosity

b) New Horizon

Which of the following is not a clue to the formation of the solar system? a) The number of small rocky planets is equal to the number of large gas-rich planets. b) There are a large number of small rocky and icy objects in different regions of the solar system. c) The planets and moons generally orbit in the same plane. d) The Earth has an unusually large moon. e) Uranus has a large tilt to its rotation axis.

a) The number of small rocky planets is equal to the number of large gas-rich planets.

Which of the following is not a characteristic of the outer planets? a) They have very few, if any, satellites. b) They are primarily made of hydrogen and helium. c) Their orbits are separated by relatively large distances. d) They all have rings.

a) They have very few, if any, satellites.

All four of the giant outer planets-Jupiter, Saturn, Uranus, and Neptune-have rings. a) True b) False

a) True

All planets orbit the Sun in the same direction (counterclockwise as viewed from above Earth's North Pole). a) True b) False

a) True

Oceans cover more of Earth's surface than land. a) True b) False

a) True

The jovian planets have no solid surface. a) True b) False

a) True

The planet in our solar system with the highest average surface temperature is _________________. a) Venus b) Neptune c) Earth d) Mercury

a) Venus

The spacecraft called Curiosity is _____. a) a rover on Mars b) an orbiter studying Jupiter c) currently orbiting Saturn d) a robotic lander on Venus

a) a rover on Mars

According to the scale model of the solar system used in Chapter 1, where does the asteroid belt lie? a) between Mars and Jupiter, around the National Air and Space Museum b) between Uranus and Neptune, around the Hirshorn Museum c) between Neptune and Pluto, around the Art and Industries Building d) beyond Neptune, but still within the Mall e) well beyond the orbits of the planets, and off the scale completely (i.e. in a different state)

a) between Mars and Jupiter, around the National Air and Space Museum

When we say that jovian planets contain significant amounts of hydrogen compounds, we mean all the following chemicals except ______. a) carbon dioxide b) methane c) water d) ammonia

a) carbon dioxide

What is the order in which the 4 types of exploratory spacecraft are likely to be sent to planets? a) flyby, orbiter, lander, sample return b) lander, orbiter, flyby, sample return c) sample return, flyby, lander, orbiter d) flyby, lander, sample return, orbiter e) sample return, orbiter, lander, flyby

a) flyby, orbiter, lander, sample return

Which moons are sometimes called the Galilean moons? a) The moons orbiting Uranus, which was once named "planet Galileo." b) The four largest moons of Jupiter: Io, Europa, Ganymede, and Callisto. c) The moons that orbit their planet "backward" compared to their planet's rotation, such as Neptune's moon Triton. d) The two largest moons in the solar system: Ganymede and Titan.

b) The four largest moons of Jupiter: Io, Europa, Ganymede, and Callisto.

What is the primary reason why a Pluto flyby mission would be cheaper than a Pluto orbiter? a) The flyby can use less expensive cameras than the orbiter. b) The fuel needed for an orbiter to slow down when it reaches Pluto adds a lot of weight to the spacecraft. c) The fuel needed for an orbiter to slow down when it reaches Pluto is very expensive in and of itself. d) The question is incorrect; in general, orbiters are cheaper than flybys. e) The flyby is easier to design than the orbiter.

b) The fuel needed for an orbiter to slow down when it reaches Pluto adds a lot of weight to the spacecraft.

Which of the following is not a characteristic of jovian planets? a) They all have many moons. b) They have a higher density than terrestrial planets. c) They are larger than terrestrial planets. d) They are farther from the Sun and farther apart from each other than the terrestrial planets. e) They have deep atmospheres made of hydrogen, helium, and hydrogen compounds.

b) They have a higher density than terrestrial planets.

Which of the following planets has the most dense atmosphere? a) Mercury b) Venus c) Earth d) Mars

b) Venus

What would we see if we could look at our solar system, without a telescope, from a spaceship beyond Neptune's orbit? a) We would see the Sun, but nothing else. b) We would see the Sun and the largest planets as pinpoints of light, but nothing else. c) We would see the Sun, all the planets, and their moons, but nothing else. d) We would see the Sun, all the planets and moons, and the largest asteroids and comets.

b) We would see the Sun and the largest planets as pinpoints of light, but nothing else.

Where are most of the known asteroids found? a) in the Kuiper belt b) between the orbits of Mars and Jupiter c) between the orbits of the terrestrial planets d) in the Oort cloud e) between the orbits of the jovian planets

b) between the orbits of Mars and Jupiter

Planetary orbits are: a) very eccentric (stretched-out) ellipses and in the same plane. b) fairly circular and in the same plane. c) fairly circular but oriented in every direction.

b) fairly circular and in the same plane.

The most abundant ingredient of the Sun and Jupiter is: a) ionized metal. b) hydrogen. c) ammonia.

b) hydrogen.

What process created the elements from which the terrestrial planets were made? a) the Big Bang b) nuclear fusion in stars c) chemical processes in interstellar clouds d) their origin is unknown.

b) nuclear fusion in stars

What characteristic of the planets is nearly the same for all planets? a) composition b) orbit shape and orientation c) rotation period (length of day) d) size e) temperature

b) orbit shape and orientation

Suppose you view the solar system from high above Earth's North Pole. Which of the following statements about planetary orbits will be true? a) All the planets except Uranus orbit the Sun counterclockwise; Uranus orbits in the opposite direction. b) The inner planets orbit the Sun counterclockwise, whereas the outer planets orbit the Sun clockwise. c) All the planets orbit counterclockwise around the Sun. d) The inner planets orbit the Sun clockwise, whereas the outer planets orbit the Sun counterclockwise.

c) All the planets orbit counterclockwise around the Sun.

How does the Earth-Sun distance compare with the Sun's radius? a) It's about 10 times larger. b) It's about 50 times larger. c) It's about 200 times larger. d) It's about 1000 times larger.

c) It's about 200 times larger.

Which of the following is not an advantage of spacecraft flybys over ground-based telescope observations? a) Spacecraft can view "backlit" views of planetary rings. b) Spacecraft can make highly detailed images of the planet and its moons. c) Spacecraft can monitor changes in a planet's atmosphere over long times. d) Spacecraft can sample the gravitational field of a planet. e) Spacecraft can measure local magnetic fields.

c) Spacecraft can monitor changes in a planet's atmosphere over long times.

Which of the following is not a characteristic of the inner planets? a) They are relatively smaller than the outer planets. b) They all have solid, rocky surfaces. c) They all have substantial atmospheres. d) Their orbits are relatively closely spaced. e) They have very few, if any, satellites.

c) They all have substantial atmospheres.

Where do asteroids come from? a) There are the remains of a planet between Mars and Jupiter that broke up. b) They are escaped small moons. c) They are leftover planetesimals from the inner solar system. d) They are leftover planetesimals from the outer solar system.

c) They are leftover planetesimals from the inner solar system.

Why do orbiters typically cost more than flyby missions? a) They typically carry more scientific instruments. b) They need expensive protection from the charged particles in a planet's magnetosphere. c) They must carry extra fuel so that they can go into orbit. d) They require more powerful radio systems to transmit data to Earth. e) all of the above

c) They must carry extra fuel so that they can go into orbit.

Which planet has the largest tilt to its rotation axis? a) Jupiter b) Saturn c) Uranus d) Neptune e) They all have similar tilts.

c) Uranus

The planet closest in size to Earth is a) Pluto. b) the Moon. c) Venus. d) Mars. e) Mercury.

c) Venus.

Which of the following is farthest from the Sun? a) a comet in the Kuiper belt b) Pluto c) a comet in the Oort cloud d) an asteroid in the asteroid belt e) Neptune

c) a comet in the Oort cloud

According to the scale model of the solar system used in Chapter 1, the Sun is the size of a grapefruit. How far away from Earth is it? a) about an inch away b) about a foot away c) about 40 feet away d) about a block away e) about a mile away

c) about 40 feet away

Which terrestrial planets have had volcanic activity at some point in their histories? a) only Earth b) Earth and Mars c) all of them

c) all of them

Where does nuclear fusion occur in the Sun? a) on the surface b) just above the visible surface c) in its core d) anywhere below the surface e) all of the above

c) in its core

Large moons orbit their planets in the same direction the planet rotates: a) rarely. b) half of the time. c) most of the time.

c) most of the time.

What is aerobraking? a) the destruction of a spacecraft by the intense pressure as it descends into the atmosphere b) the controlled landing of a spacecraft on a planetary surface c) the technique of using a planetary atmosphere to change the orbit of a spacecraft d) the gradual decrease of speed as a spacecraft leaves the solar system e) the use of a planetary atmosphere to redirect a spacecraft to another planet

c) the technique of using a planetary atmosphere to change the orbit of a spacecraft

What patterns can been seen comparing the terrestrial planets (Mercury, Venus, Earth, Mars) to the Jovian planets (Jupiter, Saturn, Uranus, Neptune)? a) The jovian planets are much more massive. b) The terrestrial planets are much more dense. c) The terrestrial planets are rocky and the jovian planets are gaseous. d) All of the above e) A and C.

d) All of the above

Which is the densest planet in the solar system? a) Jupiter b) Venus c) Mars d) Earth e) Mercury

d) Earth

What is the Oort cloud? a) It is a great cloud of gas that resides far beyond the orbit of Pluto. b) It is another name for the cloud of gas from which our solar system was born. c) It is a giant storm in the atmosphere of Saturn. d) It's not really a cloud at all, but rather refers to the trillion or so comets thought to orbit the Sun at great distances.

d) It's not really a cloud at all, but rather refers to the trillion or so comets thought to orbit the Sun at great distances.

Pluto is different from the outer planets in all of the following ways except which one? a) Its orbit is not very close to being circular. b) It is made mostly of ices. c) It has few moons. d) Its surface temperature is very cold. e) It doesn't have rings.

d) Its surface temperature is very cold.

Which planet, other than Earth, has visible water ice on it? a) Mercury b) Venus c) the Moon d) Mars e) Jupiter

d) Mars

Which lists the planets in order of increasing size (radius)? a) Mercury, Earth, Mars, Venus, Jupiter, Saturn, Uranus, Neptune b) Mercury, Venus, Mars, Earth, Neptune, Uranus, Jupiter, Saturn c) Earth, Mercury, Venus, Mars, Saturn, Jupiter, Neptune, Uranus d) Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter e) Mars, Earth, Mercury, Venus, Saturn, Uranus, Neptune, Jupiter

d) Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter

Which planets have a rocky, relatively dense composition? a) Jupiter, Saturn, Earth, and Mars b) Uranus, Neptune, Earth, and Mars c) Jupiter, Saturn, Uranus, and Neptune d) Mercury, Venus, Earth, and Mars

d) Mercury, Venus, Earth, and Mars

Which of the following is not a pattern of motion in our solar system? a) Planets all orbit the same direction as the Sun's spin. b) Planets all orbit in the same direction. c) Large planets all have many moons orbiting them. d) Planets all rotate in the same direction.

d) Planets all rotate in the same direction.

Which of the following statements about our Sun is not true? a) The Sun contains more than 98% of all the mass in our solar system. b) The Sun is a star. c) The Sun is made mostly of hydrogen and helium. d) The Sun's diameter is about 5 times that of Earth.

d) The Sun's diameter is about 5 times that of Earth.

Where do comets come from? a) There are the remains of a planet between Mars and Jupiter that broke up. b) They are escaped small moons. c) They are leftover planetesimals from the inner solar system. d) They are leftover planetesimals from the outer solar system.

d) They are leftover planetesimals from the outer solar system.

What spacecraft flew by Jupiter, Saturn, Uranus and Neptune? a) Galileo b) Cassini c) Voyager 1 d) Voyager 2 e) none of the above

d) Voyager 2

Which of the following statements about Mars is not true? a) It is frozen today but once had flowing water. b) We have landed spacecraft on its surface. c) It is considered part of our inner solar system. d) We could survive on Mars without spacesuits, as long as we brought oxygen in scuba tanks.

d) We could survive on Mars without spacesuits, as long as we brought oxygen in scuba tanks.

What is the value of comparative planetology? a) It helps us learn about a planet by studying processes that affect all planets. b) It helps us understand planets around other stars that can be studied individually in great detail. c) It helps us develop a theory for the formation of the solar system. d) all of the above e) A and B

d) all of the above

According to the scale model of the solar system used in Chapter 1, where does the Kuiper belt lie? a) between Mars and Jupiter, around the National Air and Space Museum b) between Uranus and Neptune, around the Hirshorn Museum c) between Neptune and Pluto, around the Art and Industries Building d) beyond Neptune, but still within the Mall e) well beyond the orbits of the planets, and off the scale completely (i.e. in a different state)

d) beyond Neptune, but still within the Mall

How do comets differ from asteroids? a) They are mostly ices, not rock. b) Their orbits are usually much farther from the Sun. c) They are leftover pieces of a smashed planet. d) all of the above e) A and B

e) A and B

Which of the following planets has polar ice caps? a) Earth b) Mars c) Mercury d) all of the above e) A and B

e) A and B

Where do asteroids orbit? a) between Mars and Jupiter b) in the same plane as the planets c) some in the plane of the planets, some at large angles to it d) between Neptune and Pluto e) A and C

e) A and C

How do asteroids differ from comets? a) Asteroids and comets are both made of rocky and icy material, but asteroids are smaller in size than comets. b) Asteroids are made of icy material and are less dense than the comets, which are rockier. c) Asteroids are made of icy material and are denser than the comets, which are more rocky. d) Asteroids are rocky bodies and are less dense than the comets, which are made of icy material. e) Asteroids are rocky bodies and are denser than the comets, which are made of icy material.

e) Asteroids are rocky bodies and are denser than the comets, which are made of icy material.

Most of the solar system's planets a) are made of rocks and minerals. b) are made of gas. c) orbit the Sun in the same direction. d) rotate in the same direction as they orbit the Sun. e) C and D

e) C and D

Which planet has a large moon that orbits in the opposite direction of the planet's rotation? a) Earth b) Jupiter c) Saturn d) Uranus e) Neptune

e) Neptune

Which planet has the highest average surface temperature, and why? a) Mars, because of its red color b) Jupiter, because it is so big c) Mercury, because of its dense carbon dioxide atmosphere d) Mercury, because it is closest to the Sun e) Venus, because of its dense carbon dioxide atmosphere

e) Venus, because of its dense carbon dioxide atmosphere

Which of the following planets has rings? a) Jupiter b) Saturn c) Uranus d) Neptune e) all of the above

e) all of the above

Which planet has a ring system? a) Neptune b) Uranus c) Jupiter d) Saturn e) all of the above

e) all of the above

Astronomers have decided that, rather than being a planet, Pluto is really just a large member of a) the moon system around Neptune. b) an extrasolar planetary system. c) the asteroid belt. d) the Oort cloud. e) the Kuiper belt.

e) the Kuiper belt.

According to the scale model of the solar system used in Chapter 1, where does the Oort cloud lie? a) between Mars and Jupiter, around the National Air and Space Museum b) between Uranus and Neptune, around the Hirshorn Museum c) between Neptune and Pluto, around the Art and Industries Building d) beyond Neptune, but still within the Mall e) well beyond the orbits of the planets, and off the scale completely (i.e. in a different state)

e) well beyond the orbits of the planets, and off the scale completely (i.e. in a different state)