Deck 10: Worlds of Gas and Liquidthe Giant Planets

Question 1

Referring to the figure below, what is the angular diameter of Neptune if its diameter is 50,000 km and its distance is 30 astronomical units (AU)? Recall that 1 AU = 1.5 * 10¹¹ meters.

A) 45 arcseconds
B) 30 arcseconds
C) 20 arcseconds
D) 10 arcseconds
E) 2 arcseconds

Answer 1

2 arcseconds

Question 2

Aside from Jupiter, which giant planets have atmospheric bands and storms?

A) Saturn only
B) Uranus only
C) Neptune only
D) all of Saturn, Uranus, and Neptune
E) none of these

Answer 2

all of Saturn, Uranus, and Neptune

Question 3

Assuming that a planet's axial tilt is the most important factor influencing its seasons, then ________ has the most extreme seasons of any planet in the Solar System.

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

Answer 3

Uranus

Question 4

As a group, the giant planets all rotate ________ terrestrial planets.

A) faster than
B) slower than
C) the same as
D) retrograde compared to
E) sideways compared to

Question 5

Which planet receives the least amount of energy from the Sun?

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

Question 6

The giant planets are made primarily of

A) water and carbon dioxide.
B) oxygen and nitrogen.
C) methane.
D) molecular hydrogen and helium.
E) ammonia.

Question 7

Which giant planet has the most prominent band structures?

A) Jupiter
B) Saturn
C) Uranus
D) Neptune
E) All of these have prominent band structures.

Question 8

Each season on Uranus lasts approximate 21 Earth years because

A) Uranus takes a very long time to orbit the Sun.
B) Uranus rotates very slowly.
C) Uranus's rotational axis is tipped by 45 degrees relative to it orbital axis.
D) Atmospheric circulation is ineffective in transferring heat in Uranus's atmosphere.
E) Uranus has many strong storms.

Question 9

Why are Jupiter and Saturn not perfectly spherical?

A) They formed from the collision of two large planetesimals.
B) They rotate rapidly.
C) They have storms that develop preferentially along their equators.
D) They have very active auroras that heat the atmospheres along the poles.
E) They have so much more gravity that the poles get pulled harder than the equators.

Question 10

Jupiter is approximately ________ times more massive than Earth.

A) 10
B) 50
C) 300
D) 1,000
E) 10,000

Question 11

Impurities in the ice crystals in Jupiter's atmosphere cause

A) clouds to have different colors.
B) molecular gases to be well mixed at all altitudes.
C) cloud layers to have different temperatures.
D) cloud layers to have different speeds.
E) massive lightning storms.

Question 12

Which of the giant planets was predicted to exist mathematically before it was ever seen through a telescope?

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

Question 13

Which of the following methods provides the most accurate measurement of a distant planet's radius?

A) the radial velocity method
B) Earth-based radar measurements
C) timing stellar occultations
D) visible angular size measured by telescope
E) timing wind patterns

Question 14

Which of the following planets has an average density that is less than that of liquid water?

A) Uranus
B) Saturn
C) Neptune
D) Mars
E) Earth

Question 15

Which of these planets has a composition that is most like the Sun?

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

Question 16

Assume that you discovered a new planet in the Solar System.To study it, you measured the orbital period and semimajor axis of one of its moons and deduced that the planet's mass was 4 *0²⁵ kg (7 M_Earth).Then you observed the planet occult a background star and deduced that its radius is 12,000 km (2 R_Earth).What is this planet's average density? Is this planet's chemical composition more similar to a rocky terrestrial planet or a giant planet? For comparison, the density of iron, rock, and water are approximately 9,000 kg/m³, 3,000 kg/m³, and 1,000 kg/m³, respectively.

A) The planet's average density is 1,200 kg/m³, and its composition is similar to that of giant planets.
B) The planet's average density is 1,200 kg/m³, and its composition is similar to that of terrestrial planets.
C) The planet's average density is 3,100 kg/m³, and its composition is similar to that of terrestrial planets.
D) The planet's average density is 5,500 kg/m³, and its composition is similar to that of giant planets.
E) The planet's average density is 5,500 kg/m³, and its composition is similar to that of terrestrial planets.

Question 17

Which of these observations would allow you to measure the mass of a planet?

A) the planet's orbital period
B) the planet's rotational period
C) the planet's distance from the Sun
D) the orbit of one of that planet's moons
E) the planet's temperature

Question 18

All the giant planets except ________ experience seasons.

A) Jupiter
B) Saturn
C) Uranus
D) Neptune
E) None of these experience seasons.

Question 19

Jupiter's mass is ________ times more than the mass of all the other planets in our Solar System combined.

A) around 10
B) around 2
C) 100
D) 1,000
E) 0.5

Question 20

Jupiter and Saturn are composed primarily of

A) hydrogen.
B) helium.
C) water.
D) ammonia.
E) carbon.

Question 21

A planet will have bands in its atmosphere like Jupiter and Saturn if

A) the planet is more than 3 AU from the Sun.
B) the planet rotates slowly.
C) the wind speeds vary greatly with latitude.
D) the planet has a high temperature.
E) the planet has a large mass.

Question 22

Why aren't all clouds on Jupiter white, like on Earth?

A) Jupiter's clouds are made of methane.
B) Jupiter's clouds are made of carbon dioxide.
C) There are chemical impurities in the ice crystals in Jupiter's clouds.
D) The Sun is not as bright when viewed from Jupiter compared to what it looks like from Earth.
E) For the same reason that we see colors in rainbows on Earth.

Question 23

If you monitor Jupiter's atmosphere and you see a storm near the equator move from a longitude of 60° west to a longitude of 80° west over six days, what is the wind speed at this storm's latitude on Jupiter? Note that these positions are measured on a coordinate system that rotates with the planet's interior, and the radius of Jupiter is 7.2 * 10⁷ m.

A) 700 m/s
B) 300 m/s
C) 100 m/s
D) 50 m/s
E) 500 m/s

Question 24

When you look at the visible surface of a gas giant planet, you are looking at that planet's

A) oceans.
B) core.
C) atmosphere.
D) metallic hydrogen.
E) solid surface.

Question 25

The figure below shows a drawing of bands in the atmosphere of Jupiter, and the arrows indicate the direction the winds are blowing in those bands.At which of the labeled locations would you be most likely to find a vortex storm?

A) A
B) B
C) C
D) D
E) E

Question 26

Band systems on Saturn, Uranus, and Neptune are most prominent when viewed in which wavelength regime?

A) visible
B) infrared
C) ultraviolet
D) X-ray
E) microwave

Question 27

If convection on Jupiter weakened, what would happen to the storms in the upper atmosphere?

A) They would get stronger.
B) They would get weaker.
C) They would stay the same strength but become larger.
D) They would begin to rotate the opposite direction.
E) They would move deeper into the planet.

Question 28

If you tracked the motion of the clouds near Jupiter's Great Red Spot, which of the following figures shows the correct motion you would observe?

A) A
B) B
C) C
D) D
E) E

Question 29

What causes the distinct bluish tint of the ice giants Uranus and Neptune?

A) Methane in their atmospheres preferentially absorbs the red component of the Sun's light and reemits the blue part, imparting the bluish tint.
B) Water ice in their atmospheres preferentially absorbs infrared light from the Sun and reemits the blue part, imparting the bluish tint.
C) There is less red light from the Sun reaching ice giants at their large distances, resulting in their bluish appearance.
D) The clouds consist of hydrocarbons producing their own light, which comes out in the blue region of the spectrum.
E) Metallic hydrogen within the planet reflects blue light but not red light.

Question 30

The Great Red Spot, Jupiter's most prominent storm system, has a diameter that is approximately ________ times Earth's diameter.

A) 2
B) 5
C) 10
D) 50
E) 100

Question 31

Which of the following giant planets radiates more energy into space than it receives from the Sun?

A) Jupiter
B) Saturn
C) Neptune
D) all three of Jupiter, Saturn, and Neptune
E) none of these

Question 32

In the figure below, Uranus and Neptune do not have bands as distinct as those on Jupiter and Saturn.This is because Uranus and Neptune

A) have wind speeds that vary more smoothly with latitude than the winds of Jupiter or Saturn.
B) are composed entirely of hydrogen and helium and lack more complex molecules.
C) are much closer to the Sun and much colder.
D) rotate 10 times slower.
E) have larger masses.

Question 33

How is the atmosphere of Saturn similar to the atmosphere of Earth?

A) They are both made of mostly hydrogen and helium.
B) They both create magnetic fields.
C) They both have jet streams and periods of stormy and calm weather.
D) They both rotate in less than 11 hours.
E) They both have a seamless transition between gas and liquid.

Question 34

If you monitor Saturn's atmosphere and you see a storm near its equator at a longitude of 0° west on one day and at a longitude of 90° west three days later, what is the average wind speed on Saturn at this storm's latitude? Note that these positions are measured on a coordinate system that rotates with the planet's interior, and the radius of Saturn is 6 *10⁷ m.

A) 720 m/s
B) 120 m/s
C) 360 m/s
D) 540 m/s
E) 1,440 m/s

Question 35

The poles of Uranus can have a higher temperature than its equator because Uranus

A) has a large axial tilt relative to its equator.
B) has a high mass.
C) is mostly made of water.
D) is far from the Sun.
E) has large storms on the surface.

Question 36

Where are atmospheric vortices usually found on the giant planets?

A) deep within the atmosphere, out of view from us on Earth
B) between oppositely directed zonal winds
C) only on the equator, where wind velocities are highest
D) only at the poles, where wind velocities are smallest
E) only at mid-latitudes

Question 37

The colors of the cloud bands on Jupiter and Saturn are due primarily to differences in their

A) wind speeds.
B) chemical compositions.
C) altitudes.
D) temperatures.
E) densities.

Question 38

The Jovian atmospheric vortices are created by a combination of the Coriolis effect and

A) Hadley cells.
B) convection.
C) their strong magnetic fields.
D) solar radiation.
E) chemical reactions.

Question 39

Uranus and Neptune are bluish green in color because they contain large amounts of

A) ammonia.
B) methane.
C) water vapor.
D) hydrocarbons.
E) oxygen.

Question 40

Why do we find methane clouds above water clouds in the atmosphere of Saturn?

A) Methane clouds are less dense than water clouds.
B) Methane is far more plentiful than water on Saturn.
C) Methane is in a gas state at lower temperatures than water.
D) We can't observe the methane clouds that are deeper in the atmosphere.
E) all of these

Question 41

If Jupiter's radius is contracting at a rate of 2 cm/yr it would explain

A) differential convection that powers Jupiter's Great Red Spot.
B) Jupiter's rotation rate slowing with time.
C) Jupiter's shape being oblate.
D) Jupiter radiating more heat than it receives from the Sun.
E) Jupiter's orbit around the Sun getting smaller.

Question 42

As you move from the top atmospheric layer toward the center of a gas planet, the temperature ________ and the pressure ________.

A) increases; decreases
B) increases; increases
C) decreases; decreases
D) decreases; increases
E) increases; stays the same

Question 43

Why would a satellite orbiting close to Jupiter have a very hard time detecting solar wind particles?

A) Jupiter's strong gravity pulls them into the planet.
B) Jupiter is too far away from the Sun to get any solar wind.
C) The satellite would be moving too fast in its orbit to catch any of them.
D) The Great Red Spot pushes them away from Jupiter.
E) Jupiter's magnetosphere deflects them.

Question 44

Uranus and Neptune contain smaller percentages of hydrogen and helium than Jupiter and Saturn probably because Uranus and Neptune ________ than Jupiter and Saturn.

A) are much smaller in radius
B) are much warmer
C) are much colder
D) formed later
E) formed earlier

Question 45

Neptune and Uranus probably took longer to form than Jupiter and Saturn because the solar nebula was ________ at the radius of Neptune and Uranus.

A) rotating faster
B) composed of rockier planetesimals
C) not as dense
D) hotter
E) colder

Question 46

The strongest planetary magnetic fields in the Solar System are found on which planet?

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

Question 47

What measurement tells us that the interiors of Uranus and Neptune are made of mostly water?

A) their mass
B) their distance from the sun
C) their average densities
D) their temperatures
E) their colors

Question 48

Of the giant planets, only Jupiter and Saturn have thick inner layers of

A) liquid rock.
B) solid rock.
C) metallic hydrogen.
D) liquid methane.
E) water.

Question 49

If the flux of sunlight on a planet suggested its temperature should be 200 K but its actual temperature was 220 K, then how much more energy does this planet emit relative to the energy it receives from its parent star?

A) 5.3 times more energy
B) 2.1 times more energy
C) 2.9 times more energy
D) 1.1 times more energy
E) 1.5 times more energy

Question 50

We refer to some of the inner regions of Jupiter and Saturn as metallic hydrogen because they

A) are as dense as lead.
B) are solid.
C) provide support for the upper layers of hydrogen and helium.
D) efficiently conduct electricity.
E) are found in the core like iron is found at the core of Earth.

Question 51

The figure below shows a cutaway drawing of some of the layers inside the atmosphere of Jupiter.The rocky core is located at the center.Which of these is a possible list of what the layers contain, starting with layer 1 and moving to layer 3?

A) gas, solid, liquid
B) gas, smooth transition from gas to solid, solid
C) gas, distinct line between gas and solid, solid
D) gas, smooth transition from gas to liquid, solid
E) gas, distinct line between gas and liquid, liquid

Question 52

Where do Uranus's and Neptune's strong magnetic fields originate?

A) molten rocky cores
B) salty oceans
C) large magnetospheres
D) metallic hydrogen layers
E) methane clouds

Question 53

Each giant planet has a core made of ________ that is 5 to 10 times the mass of Earth.

A) hydrogen
B) rocky material
C) water
D) hydrocarbons
E) methane

Question 54

If you could watch Saturn form starting from the beginning of the Solar System, which of these features of Saturn would come together first?

A) magnetosphere
B) metallic hydrogen
C) molecular hydrogen
D) rocky core
E) ammonia ice

Question 55

You observe a gas giant planet that is much warmer that its expected equilibrium temperature.This is evidence that the gas giant is

A) generating more heat than it receives.
B) rotating rapidly.
C) rotating on an axis that is highly tilted.
D) experiencing extreme turbulence in its middle layers.
E) fusing hydrogen into helium in its core.

Question 56

What is the most likely reason that Jupiter radiates more energy than it receives from the Sun?

A) There is nuclear fusion occurring near its core, which releases heat.
B) There is a greenhouse effect operating in the Jovian atmosphere.
C) It is still contracting under its own gravity.
D) It is undergoing tidal heating in its interior due to the gravitational pull of Saturn.
E) Friction between the cloud belts results in a heating effect.

Question 57

Despite the high temperatures deep in the interior of giant planets, their cores remain liquid because

A) they are under very high pressures.
B) gravitational potential energy is being converted into thermal energy in the cores.
C) they are composed of heavy materials like rock and water.
D) their rotations are rapid compared to those of the terrestrial planets.
E) the giant planets have strong magnetic fields.

Question 58

Why are Uranus and Neptune less massive than Jupiter and Saturn?

A) because they formed before Jupiter and Saturn, when there wasn't enough gas in the solar nebula yet
B) because they formed farther out in the solar nebula, where there was less gas available
C) because they formed very close to the Sun, where intense solar radiation evaporated some of their atmosphere into space
D) because they are composed of mostly ice, and there is less ice farther out in the solar nebula
E) because they formed around a different star, and were captured by the Sun later on.

Question 59

If you were to fly to Jupiter from Earth, which of these parts of Jupiter would you come into contact with first?

A) magnetosphere
B) metallic hydrogen
C) molecular hydrogen
D) rocky materials
E) stratosphere

Question 60

What would you observe in order to accurately measure the rotational period of a giant planet?

A) clouds in the atmosphere
B) bands of storms on the equator
C) stellar occultations
D) synchrotron emission
E) the orbit of its moons

Question 61

Many extrasolar planets identified by astronomers have masses exceeding that of Jupiter.How does this lead to higher densities for these planets?

A) They are expected to have formed closer to their parent stars, where the protostellar nebula was denser.
B) Their higher masses lead to stronger gravitational forces, causing them to shrink with time, which leads to higher densities
C) Their higher masses have led them to accrete more planetesimals, resulting in higher densities than Jupiter
D) They are expected to orbit far from their parent stars, resulting in colder, denser atmospheres than Jupiter
E) They were able to fuse hydrogen into helium for a short period of time, resulting in denser cores than Jupiter has

Question 62

Gas giants that have larger radii than Jupiter but that are also less massive are called

A) super Jupiters.
B) mini-Neptunes.
C) brown dwarfs.
D) hot Jupiters.
E) puffy Jupiters.

Question 63

What is the main difference between "super-Earths" and "mini-Neptunes"?

A) Mini-Neptunes are bluer.
B) Mini-Neptunes are larger and less dense.
C) Mini-Neptunes are much denser.
D) Mini-Neptunes have radii at least 10 times that of super-Earths.
E) Super-Earths have liquid water on their surfaces.

Question 64

The figure below is a picture of Saturn taken by the Hubble Space Telescope.What is causing the circle of light seen near Saturn's pole?

A) Solar wind particles are being trapped by Saturn's magnetic field, causing an aurora.
B) Strong storms on Saturn are causing lightning strikes.
C) Saturn's tilt is causing that area of the planet to be warmer, so it gives off bluer light.
D) Metallic hydrogen is being released from the surface of Saturn.
E) Saturn is giving off energy because it is shrinking.

Question 65

Jupiter emits a large amount of radio emission because

A) charged particles blasted off of Io's surface move through Jupiter's magnetic field.
B) violent storms in its atmosphere produce a lot of lightning.
C) Jupiter is so cold that its blackbody radiation peaks at radio wavelengths.
D) Jupiter's thick inner shell of metallic hydrogen is electrically conductive.
E) Jupiter's core has a very high temperature and pressure.

Question 66

When charged particles oscillate around the magnetic field lines of a planet, in what region of the spectrum do they emit electromagnetic radiation?

A) optical
B) infrared
C) X-rays
D) radio
E) gamma rays

Question 67

What produces Jupiter's strong auroras?

A) charged particles from the Sun
B) charged particles emitted near the equator of Jupiter
C) charged particles that have separated from Jupiter's rings
D) charged particles expelled by volcanoes on Io
E) charged particles from deep space (cosmic rays)

Question 68

Saturn has a lower abundance of helium in its atmosphere than Jupiter does.Why?

Question 69

If we measure the spectrum of radiation coming from different clouds in Jupiter's atmosphere and we find that a cloud that appears white in visible light emits the largest number of photons at a wavelength of 3 *10^-5 m, whereas a cloud that appears brown in visible light emits the largest number of photons at a wavelength of 1.9 * 10^-5 m, how do the temperatures of the clouds compare?

Question 70

Summarize the major physical properties that differ between gas giant planets and terrestrial planets.

Question 71

Exoplanets a few times the size of Earth are commonly found in other solar systems, and are called

A) mini-Jupiters.
B) ice giants.
C) puffy Jupiters.
D) super-Earths.
E) hot Jupiters

Question 72

Compare the flux of sunlight at Earth's orbit to that at Saturn's orbit.Note that Saturn's average distance from the Sun is 9.5 AU.

Question 73

What is the long, snaking dark line found in the visible light image of Saturn shown below?
Is there an analogous feature on Earth?

Question 74

What could have caused the planets to migrate through the Solar System?

A) gravitational pull from the Sun
B) interaction with the solar wind
C) accreting gas from the solar nebula
D) gravitational pull from other planets
E) differentiation of their interiors

Question 75

What causes the horizontal bands on Jupiter and Saturn to have different colors? How can they be used to probe different altitudes in their atmospheres?

Question 76

What effect does Jupiter's rotation have on its clouds?

Question 77

What is the ratio of Jupiter's volume to Earth's volume if both planets can be modeled as spheres and Jupiter's radius is 11 times that of Earth's?

Question 78

Suppose Neptune moves with an average orbital speed of 3.5 km/s.If it takes Neptune four hours to pass directly in front of a star, what is Neptune's diameter? Give Neptune's radius in units of Earth diameters, where the diameter of Earth is 12,800 km.

Question 79

Explain why methane never freezes in the upper atmospheres of Jupiter and Saturn, and how this leads to the different appearance of Jupiter and Saturn compared to Uranus and Neptune.

Question 80

Which of the following effects is one of the predictions made by models of our Solar System that include planetary migration?

A) Jupiter has four large moons, with the rest being smaller asteroid-sized objects.
B) Mars was a large asteroid that got bigger due to material from Jupiter.
C) The orbits of the inner terrestrial planets became stabilized, allowing them to reside near or in the habitable zone for life.
D) Pluto would have formed near Earth, but was knocked into a much large orbit.
E) Uranus and Neptune prevented harmful debris from entering the inner solar system.