Deck 8: Jovian Planet Systems

Question 1

Why does Jupiter have several distinct cloud layers?

A) Different layers represent clouds made of gases that condense at different temperatures.
B) Different layers represent the various regions where the temperature is cool enough for liquid water to condense.
C) Different gases are present at different altitudes in Jupiter's atmosphere.
D) Winds prevent clouds from forming at some altitudes, so we see clouds only at the other altitudes.
E) Clouds form randomly, so on average there are always several layers.

Answer 1

A

Question 2

Which moon did the Huygens spacecraft land on?

A) Ganymede
B) Callisto
C) Europa
D) Titan
E) Triton

Answer 2

D

Question 3

Why is Jupiter denser than Saturn?

A) It is made of a different composition than Saturn, including a higher proportion of hydrogen compounds and rocks.
B) The extra mass of Jupiter compresses its interior to a greater extent than that of Saturn.
C) Its core is much larger than Saturn's.
D) It has a greater proportion of helium to hydrogen compared to Saturn.
E) Scientists do not know why this is so.

Answer 3

B

Question 4

Which of the following statements about Titan is not true?

A) It may have an ocean of liquid ethane.
B) Its atmosphere is mostly nitrogen.
C) Its temperature is too cold for liquid water to exist.
D) Its surface is hidden from view by its thick atmosphere.
E) It is the coldest moon in the solar system.

Question 5

How do the jovian planet interiors differ?

A) All have cores of about the same mass, but differ in the amount of surrounding hydrogen and helium.
B) The core mass decreases with the mass of the planet.
C) The composition changes from mostly ammonia in Jupiter and Saturn to mostly methane in Uranus and Neptune.
D) The composition changes from mostly hydrogen in Jupiter and Saturn to mostly helium in Uranus and Neptune.
E) All have about the same amount of hydrogen and helium but the proportion of rocks is greater in those planets closer to the Sun.

Question 6

What is the most important reason why an icy moon is more likely to be geologically active than a rocky moon of the same size?

A) Ice has a lower melting point than rock.
B) Ice is less rigid than rock.
C) Ice contains more radioactive elements than rock.
D) Ice is affected by tidal forces to a greater extent than rock.
E) Ice is less dense than rock.

Question 7

Why are there no impact craters on the surface of Io?

A) It is too small to have been bombarded by planetesimals in the early solar system.
B) Jupiter's strong gravity attracted the planetesimals more strongly than Io and thus none landed on its surface.
C) Io did have impact craters but they have all been buried in lava flows.
D) Any craters that existed have been eroded through the strong winds on Io's surface.
E) Io's thick atmosphere obscures the view of the craters.

Question 8

What is the most abundant gas in Titan's atmosphere?

A) methane
B) nitrogen
C) hydrogen compounds
D) oxygen
E) argon

Question 9

What mechanism is most responsible for generating the internal heat of Io that drives its volcanic activity?

A) accretion
B) radioactive decay
C) differentiation
D) tidal heating
E) bombardment

Question 10

Why is Saturn almost as big as Jupiter, despite its smaller mass?

A) Jupiter's greater mass compresses it more and increasing its density.
B) Saturn's rings make the planet look bigger.
C) Saturn is further from the Sun, thus cooler, and therefore less compact.
D) Saturn has a larger proportion of hydrogen and helium than Jupiter, and is therefore less dense.
E) Jupiter's strong magnetic field constrains its size.

Question 11

How thick are Saturn's rings from top to bottom?

A) a few million kilometers
B) a few tens of thousands of kilometers
C) a few hundred kilometers
D) a few kilometers
E) a few tens of meters

Question 12

Which of the following best describes the composition of the particles forming Saturn's rings?

A) Water ice
B) Metallic grains
C) Methane ice
D) Volcanic rock
E) Hydrogen and helium

Question 13

What did the Huygens probe photograph as it landed on Titan?

A) dry, featureless plains
B) a water world of frozen ice sheets
C) a pockmarked surface covered with volcanos
D) hills, valleys and rivers
E) nothing; there was zero visibility due to the methane smog

Question 14

How many more times is the atmospheric pressure in Jupiter's core greater than the atmospheric pressure at Earth's surface?

A) 10 thousand
B) 100 thousand
C) 1 million
D) 10 million
E) 100 million

Question 15

How do astronomers think Jupiter generates its internal heat?

A) radioactive decay
B) internal friction due to its high rotation rate
C) chemical processes
D) nuclear fusion in the core
E) by contracting, changing gravitational potential energy into thermal energy

Question 16

Why is Neptune denser than Saturn?

A) It has a different composition than Saturn, including a higher proportion of hydrogen compounds and rocks.
B) It has a greater proportion of hydrogen than Saturn.
C) The extra mass of Neptune compresses its interior to a greater extent than that of Saturn.
D) Its hydrogen is molecular, whereas Saturn's hydrogen is atomic.
E) It is not denser than Saturn.

Question 17

If Jupiter were scaled to the size of a basketball, Earth would be the closest to the size of

A) a pinhead.
B) a marble.
C) a baseball.
D) a grapefruit.
E) a basketball.

Question 18

How do the size and mass of Jupiter's core compare to the size and mass of Earth?

A) It is the same size and mass.
B) It is about 10 times larger both in size and mass.
C) It is about 10 times larger in size and the same mass.
D) It is about the same size but is 10 times more massive.
E) Jupiter doesn't have a core-it is made entirely from hydrogen and helium.

Question 19

Which of the following is not due to tidal forces?

A) the synchronous rotation of the Moon around Earth
B) the volcanos on Io (a moon of Jupiter)
C) the rings of Saturn
D) the grooved terrain of Enceladus (a moon of Saturn)
E) the retrograde orbit of Triton (a moon of Neptune)

Question 20

Why do the jovian planet interiors differ?

A) The more distant planets formed in a cooler region of the solar nebula and therefore contain a greater proportion of ices than the closer jovian planets.
B) They differ due to giant impacts at the late stages of planet formation.
C) Accretion took longer further from the Sun, so the more distant planets formed their cores later and captured less gas from the solar nebula than the closer jovian planets.
D) The more distant planets had longer to form than the closer planets, since the solar nebula lasted longer at greater distances from the Sun.

Question 21

Unification in Science: One of the true pleasures of science is to discover that two rather different phenomena are really manifestations of the same set of physical principles. To this end, explain how the volcanoes on Io, the subsurface ocean on Europa, and the gaps in Saturn's rings reflect the operation of the same physical principle.

Question 22

If Jupiter were 10 times more massive, it would generate nuclear fusion in its core and be a star instead of a planet.

Question 23

Io's Volcanoes Predicted? The intense volcanic activity on Io came as somewhat of a surprise to many when it was discovered by the Voyager mission in 1979. Nevertheless, argue that all of the elements where in place to make a prediction of intense volcanic activity on Io before the Voyager mission. Search on the web for the history of Io's volcanism to see if such a prediction was actually made.

Question 24

The water-ice particles forming Saturn's rings are frozen together into a thin sheet that rotates around Saturn like a solid body.

Question 25

The mass of Saturn can be determined by applying Kepler's 3ʳᵈ Law to the motion of a single ice particle in its rings.

Question 26

The satellite Amalthea orbits Jupiter at just about the same distance in kilometers at which Mimas orbits Saturn. Yet Mimas takes almost twice as long to orbit. What can you deduce from this difference qualitatively? Since Jupiter and Saturn are not very different in radius, what else can you conclude?

Question 27

Suppose the jovian planet atmospheres were composed 100 percent of hydrogen and helium rather than 98 percent of hydrogen and helium. How would the atmospheres be different in terms of color and weather?

Question 28

Planetary rings are

A) nearer to their planet than any of the planet's large moons.
B) orbiting in the equatorial plane of their planet.
C) composed of a large number of individual particles that orbit their planet in accord with Kepler's third law.
D) known to exist for all of the jovian planets.
E) all of the above

Question 29

Titan's surface may contain lakes of liquid methane.

Question 30

Probing the Interior of Jupiter: Astronomers claim to have a reasonable model for interior structure of Jupiter. What is the observational basis for this model? Does it make any predictions that have been put to observational tests? How is the interior structure of the Earth known (review Chapter 7 if necessary)? Do you think the interior structure of Jupiter is more or less well-tested than that of the interior structure of he Earth? Explain.

Question 31

Why does it make sense that the jovian planets farther from the Sun have less mass?

Question 32

No spacecraft has landed on a Jovian planet moon.

Question 33

Hydrogen exists as a gas, liquid, and solid within Jupiter.

Question 34

What is the Cassini division of Saturn's rings?

A) a dark ring, visible from Earth, composed of dark, dusty particles
B) a large gap, visible from Earth, produced by an orbital resonance with the moon Mimas
C) the imaginary circle marking the halfway point of Saturn's rings
D) the widest ring of Saturn, located between two large ring gaps
E) the most opaque ring of Saturn, made of highly reflective ice particles

Question 35

Which of the jovian planets have rings?

A) Jupiter
B) Saturn
C) Uranus
D) Neptune
E) all of the above

Question 36

Why are Saturn's rings so thin?

A) Saturn's gravity prevents particles from migrating upwards out of the rings.
B) The "gap" moons shepherd the particles and maintain its thin profile.
C) Any particle in the ring with an orbital tilt would collide with other ring particles, flattening its orbit.
D) Solar radiation pressure keeps particles pressed into the rings.
E) The current thinness is a short-lived phenomenon that is special to this time.

Question 37

Jupiter's Great Red Spot is a low-pressure storm like a hurricane on Earth.

Question 38

Some of the moons of the jovian planets have significant atmospheres.

Question 39

The Huygens landing showed that the surface of Titan is as hard as a rock.

Question 40

If Jupiter were 10 times more massive, it would actually have a smaller radius.

Question 41

What atmospheric constituent is responsible for the blue color of Uranus and Neptune?

A) Methane
B) Hydrogen
C) Water
D) Ammonia

Question 42

Use these choices for the following questions.
A. the most volcanically active body in the solar system
B. thought to have a deep, subsurface ocean of liquid water
C. probably a captured Kuiper Belt object
D. the target of the Huygens probe, which landed on its surface.
E. the largest moon in the solar system
Which of the above applies to Ganymede?

Question 43

Use these choices for the following questions.
A. the most volcanically active body in the solar system
B. thought to have a deep, subsurface ocean of liquid water
C. probably a captured Kuiper Belt object
D. the target of the Huygens probe, which landed on its surface.
E. the largest moon in the solar system
Which of the above applies to Europa?

Question 44

Use these choices for the following questions.
A. the most volcanically active body in the solar system
B. thought to have a deep, subsurface ocean of liquid water
C. probably a captured Kuiper Belt object
D. the target of the Huygens probe, which landed on its surface.
E. the largest moon in the solar system
Which of the above applies to Io?

Question 45

How do typical wind speeds in Jupiter's atmosphere compare to typical wind speeds on Earth?

A) They are much faster than hurricane winds on Earth.
B) They are about the same as average winds on Earth.
C) They are slightly faster than average winds on Earth.
D) They are slightly slower than average winds on Earth.

Question 46

Describe the possible origins of Jupiter's vibrant colors. Contrast these with the origins of the colors of the other jovian planets.

Question 47

Contrast Jupiter's magnetosphere with that of Earth and of the other jovian planets.

Question 48

Overall, Jupiter's composition is most like that of ________.

A) the Sun
B) Earth
C) a comet
D) an asteroid

Question 49

Use these choices for the following questions.
A. the most volcanically active body in the solar system
B. thought to have a deep, subsurface ocean of liquid water
C. probably a captured Kuiper Belt object
D. the target of the Huygens probe, which landed on its surface.
E. the largest moon in the solar system
Which of the above applies to Titan?

Question 50

Jupiter's colors come in part from its three layers of clouds. Which of the following is not the primary constituent of one of Jupiter's cloud layers?

A) Clouds of sulfuric acid
B) Clouds of water
C) Clouds of ammonium hydrosulfide
D) Clouds of ammonia

Question 51

What is the Great Red Spot?

A) A long-lived, high-pressure storm on Jupiter
B) A hurricane that comes and goes on Jupiter
C) A place where reddish particles from Io impact Jupiter's surface
D) A region on Jupiter where the temperature is so high that the gas glows with red visible light

Question 52

Which of the following is not a general characteristic of the four jovian planets in our solar system?

A) They are higher in average density than are the terrestrial planets.
B) They lack solid surfaces.
C) They are composed mainly of hydrogen, helium, and hydrogen compounds.
D) They are much more massive than any of the terrestrial planets.

Question 53

Which of the following best describes the internal layering of Jupiter, from the center outward?

A) Core of rock, metal, and hydrogen compounds; thick layer of metallic hydrogen; layer of liquid hydrogen; layer of gaseous hydrogen; cloud layer
B) Core of rock and metal; mantle of lower density rock; upper layer of gaseous hydrogen; cloud layer
C) Solid rock core; layer of solid metallic hydrogen; layer of pure liquid hydrogen; cloud layer
D) Liquid core of hydrogen compounds; liquid hydrogen layer; metallic hydrogen layer; gaseous hydrogen layer; cloud layer

Question 54

What is "ice geology"? Give an example illustrating why it is important in the outer solar system.

Question 55

Which of the following statements comparing the jovian interiors is not thought to be true?

A) They all have the same exact set of internal layers, though these layers differ in size.
B) They all have cores of roughly the same mass.
C) They all have cores that contain at least some rock and metal.
D) Deep inside them, they all have pressures far higher than that found on the bottom of the ocean on Earth.

Question 56

Describe some of the results from the Cassini/Huygens mission to Saturn and its moons.

Question 57

Use these choices for the following questions.
A. the most volcanically active body in the solar system
B. thought to have a deep, subsurface ocean of liquid water
C. probably a captured Kuiper Belt object
D. the target of the Huygens probe, which landed on its surface.
E. the largest moon in the solar system
Which of the above applies to Triton?

Question 58

Describe two leading scenarios for the origin of the planetary rings. What makes us think that ring systems must be continually replenished?

Question 59

Explain how the resonance among Io, Europa, and Ganymede makes their orbits slightly elliptical.

Question 60

Why is Triton such an unusual satellite?

Question 61

Why is the radiation so intense in the region that traces Io's orbit around Jupiter (the Io torus)?

A) The region is full of gases that become ionized after they are released from volcanoes on Io.
B) Io's gravity allows this region to capture huge numbers of charged particles from the solar wind.
C) An orbital resonance between Io, Europa, and Ganymede makes the radiation intense.
D) Jupiter's strong magnetic field makes the radiation intense everywhere, and the region around Io is no different than any other region.

Question 62

Which statement about Io is true?

A) It is the most volcanically active body in our solar system.
B) It is thought to have a deep, subsurface ocean of liquid water.
C) It is the largest moon in the solar system.
D) It is the only moon in the solar system with a thick atmosphere.

Question 63

Which of the following best why we see horizontal "stripes" in photographs of Jupiter and Saturn?

A) The light stripes are regions of high clouds, and the dark stripes are regions where we can see down to deeper, darker clouds.
B) The dark and light stripes correspond to alternating bands of different chemical composition.
C) There are three different color stripes corresponding to the three different types of clouds found on these planets.
D) Dark stripes are those in which there is a stratosphere and light stripes are those with no stratosphere.

Question 64

Which statement about planetary rings is not true?

A) Saturn's rings formed along with its moons 4.6 billion years ago.
B) All four jovian planets have rings.
C) Individual ring particles orbit their planet in accord with Kepler's laws, so that particles closer in orbit faster than particles farther out.
D) Rings are always located closer to a planet's surface than any large moons.

Question 65

The Huygens probe took numerous pictures as it descended to Titan's surface in 2005. What did the pictures show?

A) Features or erosion, including what appeared to be dry river valleys and lakebeds
B) Primitive life forms
C) A densely cratered surface
D) Lava flows of molten basalt

Question 66

Suppose you could float in space just a few meters above Saturn's rings. What would you see as you looked down on the rings?

A) countless icy particles, ranging in size from dust grains to large boulders
B) a solid, shiny surface, looking much like a piece of a DVD but a lot bigger
C) dozens of large "moonlets" made of metal and rock, each a few kilometers across
D) Nothing-up close, the rings would be so completely invisible that you'd have no way to know they are there. They can be seen only from a distance.

Question 67

Which of the following statements about the moons of the jovian planets is not true?

A) Most of the moons are large enough to be spherical in shape, but a few have the more potato-like shapes of asteroids.
B) Some of the moons are big enough that we'd call them planets (or dwarf planets) if they orbited the Sun.
C) One of the moons has a thick atmosphere.
D) Many of the moons are made largely of ices.

Question 68

All the following statements are true. Which one is most important in explaining the tremendous tidal heating that occurs on Io?

A) Io orbits Jupiter on an elliptical orbit, due to orbital resonances with other satellites.
B) Io is the closest to Jupiter of Jupiter's large moons.
C) Io exhibits synchronous rotation, meaning that its rotation period and orbital period are the same.
D) Io orbits Jupiter in the Io torus, and therefore has a surface that is bombarded by many charged particles.

Question 69

What would happen to Jupiter if we could somehow double its mass?

A) Its density would increase but its diameter would barely change.
B) Its density would decrease and its diameter would double.
C) Its density would stay about the same and its volume would double.
D) It would become a star, with nuclear fusion in its core.

Question 70

Which of the following gases is not a significant ingredient of the jovian planet atmospheres?

A) Carbon dioxide
B) Hydrogen
C) Helium
D) Water

Question 71

Which large jovian moon is thought to have been captured into its present orbit?

A) Triton
B) Callisto
C) Titan
D) Io

Question 72

Which moon has a thick atmosphere made mostly of nitrogen?

A) Titan
B) Triton
C) Ganymede
D) Europa

Question 73

Uranus and Neptune have methane clouds but Jupiter and Saturn do not. Which factor explains why?

A) Temperatures on Jupiter and Saturn are too high for methane to condense.
B) Jupiter and Saturn do not contain any methane gas.
C) The rapid rotation of Jupiter and Saturn prevents methane clouds from forming.
D) The stronger gravity on Jupiter and Saturn pulls methane downward so that it can't form clouds.

Question 74

Jupiter and the other jovian planets are sometimes called "gas giants." In what sense is this term misleading?

A) They actually contain relatively little material in a gaseous state.
B) The materials they are made of are not the kinds of thing we usually think of as gases.
C) They are not in any sense "giants."
D) Actually, it's a great description, because these worlds are big and gaseous throughout.

Question 75

Which jovian planet should have the most extreme seasonal changes?

A) Uranus
B) Jupiter
C) Saturn
D) Neptune

Question 76

Which of the following best explains why many jovian moons have been more geologically active than the Moon or Mercury?

A) Jovian moons are made mostly of ice that can melt or deform at lower temperatures than can the rock and metal that make up the Moon and Mercury.
B) The jovian moons are considerably larger than the Moon and Mercury and therefore have retained much more internal heat.
C) The jovian moons probably have far more internal heat generated by radioactive decay than do the Moon or Mercury.
D) Because of their greater distances from the Sun, the jovian moons receive much less heat from the Sun.

Question 77

Which moon is considered likely to have a deep, subsurface ocean of liquid water?

A) Europa
B) Io
C) Miranda
D) Triton

Question 78

How does the strength of Jupiter's magnetic field compare to that of Earth's magnetic field?

A) Jupiter's magnetic field is about 20,000 times as strong as Earth's.
B) Jupiter's magnetic field strength is about the same as Earth's.
C) Jupiter's magnetic field is about twice as strong as Earth's.
D) Jupiter's magnetic field is much weaker than Earth's.

Question 79

According to our theory of solar system formation, why did Uranus and Neptune end up to be much less massive than Jupiter and Saturn?

A) Particles in the solar nebula were more spread out at greater distances, so that accretion took longer and there was less time to pull in gas before the solar wind cleared the nebula.
B) Ices were able to condense at the distance of Jupiter and Saturn, but only rock and metal could condense at the distances of Uranus and Neptune.
C) The colder gas in the outer regions of the solar nebula had less gravity and therefore could not gather up into such large balls as it could closer in.
D) The size differences are thought to be a random coincidence.

Question 80

Why does Jupiter have three distinct layers of clouds?

A) The three layers represent clouds made of gases that condense at different temperatures.
B) Jupiter has three different types of wind, each of which makes a different type of cloud.
C) The three layers reflect regions of Jupiter's atmosphere with different overall chemical compositions.
D) Clouds form randomly, so on average there are always three layers.