Question 1

Suppose Mimas orbited further out from Saturn than it does now. What difference, if any, would this make to the Cassini division?

Accepted Answer

A) The orbit of Mimas has no effect on the Cassini division. 
B) The Cassini division would also move further out. 
C) The Cassini division would move inward toward Saturn. 
D) The Cassini division would disappear (fill in with ring particles) and not re-form elsewhere. 
A) The orbit of Mimas has no effect on the Cassini division. 
B) The Cassini division would also move further out. 
C) The Cassini division would move inward toward Saturn. 
D) The Cassini division would disappear (fill in with ring particles) and not re-form elsewhere. B

Question 2

The Cassini observations of Jupiter suggest that, contrary to previous models, the light-colored zones on Jupiter are:

Accepted Answer

A) volcanic plumes that have been stretched around the planet by Jupiter's high speed of rotation. 
B) holes in the atmosphere through which lighter, deeper layers can be seen. 
C) regions in which the gas is falling. 
D) regions in which the gas is rising. 
A) volcanic plumes that have been stretched around the planet by Jupiter's high speed of rotation. 
B) holes in the atmosphere through which lighter, deeper layers can be seen. 
C) regions in which the gas is falling. 
D) regions in which the gas is rising. C

Question 3

Jupiter's mass is more than 300 times the mass of Earth, and Saturn has almost 100 times Earth's mass. These masses were determined by:

Accepted Answer

A) watching carefully the orbits of these planets around the Sun. 
B) measuring the deviations of the other planets from their expected orbits around the Sun. 
C) measuring the deflection of Halley's comet from its orbit when it is near Jupiter and Saturn. 
D) measuring the orbits of the satellites of these planets. 
A) watching carefully the orbits of these planets around the Sun. 
B) measuring the deviations of the other planets from their expected orbits around the Sun. 
C) measuring the deflection of Halley's comet from its orbit when it is near Jupiter and Saturn. 
D) measuring the orbits of the satellites of these planets. D

Question 4

Can charged particles from Io affect aurorae on Jupiter?

Accepted Answer

A) No. Because of the structure of Jupiter's magnetosphere, charged particles from Io cannot reach the upper atmosphere of Jupiter where aurorae form. 
B) Yes. The charged particles from Io have the opposite electric charge of those from the Sun and tend to cancel them out. Thus, the aurorae tend to darken. 
C) Yes. Charged particles from Io can join charged particles from the Sun and brighten the aurorae. 
D) No. Io is too far away to affect the aurorae in the upper atmosphere of Jupiter. 
A) No. Because of the structure of Jupiter's magnetosphere, charged particles from Io cannot reach the upper atmosphere of Jupiter where aurorae form. 
B) Yes. The charged particles from Io have the opposite electric charge of those from the Sun and tend to cancel them out. Thus, the aurorae tend to darken. 
C) Yes. Charged particles from Io can join charged particles from the Sun and brighten the aurorae. 
D) No. Io is too far away to affect the aurorae in the upper atmosphere of Jupiter.

Question 5

Jupiter has a magnetic field that is:

Accepted Answer

A) much stronger than that of Earth and greatly extended in space. 
B) about the same strength and extent as that of Earth. 
C) variable, often nonexistent, sometimes existing only at the Great Red Spot, which behaves like a sunspot. 
D) very strong and localized close to the planet. 
A) much stronger than that of Earth and greatly extended in space. 
B) about the same strength and extent as that of Earth. 
C) variable, often nonexistent, sometimes existing only at the Great Red Spot, which behaves like a sunspot. 
D) very strong and localized close to the planet.

Question 6

The dark-colored belts on Jupiter are brighter than the surrounding regions when viewed in infrared or heat radiation because:

Accepted Answer

A) chemical reactions causing the dark, visible colors also release energy and heat these regions. 
B) these regions are composed of hot dust and gases released from volcanoes and distributed around the planet by high winds. 
C) these regions are higher in Jupiter atmosphere, receive more sunlight, and hence are hotter in IR radiation. 
D) these regions are deeper and therefore hotter layers of gas in Jupiter's atmosphere. 
A) chemical reactions causing the dark, visible colors also release energy and heat these regions. 
B) these regions are composed of hot dust and gases released from volcanoes and distributed around the planet by high winds. 
C) these regions are higher in Jupiter atmosphere, receive more sunlight, and hence are hotter in IR radiation. 
D) these regions are deeper and therefore hotter layers of gas in Jupiter's atmosphere.

Question 7

On Jupiter and Saturn the wind currents move generally:

Accepted Answer

A) parallel to the equator. 
B) from north to south. 
C) from south to north. 
D) in totally random directions. 
A) parallel to the equator. 
B) from north to south. 
C) from south to north. 
D) in totally random directions.

Question 8

On what planet would you NOT expect to find an aurora?

Accepted Answer

A) Venus 
B) Earth 
C) Jupiter 
D) Saturn 
A) Venus 
B) Earth 
C) Jupiter 
D) Saturn

Question 9

Jupiter appears as a flattened, oblate spheroid in the sky because:

Accepted Answer

A) it is spinning rapidly, and is composed mostly of fluid matter. 
B) it was formed in this way at the time of planetary formation, and has solidified to this shape. 
C) tidal distortion from its moons and from the Sun have distorted its shape. 
D) it is moving rapidly around its orbit, flattening its shape. 
A) it is spinning rapidly, and is composed mostly of fluid matter. 
B) it was formed in this way at the time of planetary formation, and has solidified to this shape. 
C) tidal distortion from its moons and from the Sun have distorted its shape. 
D) it is moving rapidly around its orbit, flattening its shape.

Question 10

Each of the following provides evidence for the large amount of hydrogen in the atmosphere of Jupiter EXCEPT one. Which is the exception?

Accepted Answer

A) differential rotation 
B) calculation of the overall density of Jupiter 
C) detection of methane (CH4) in the atmosphere 
D) detection of ammonia (NH3) in the atmosphere 
A) differential rotation 
B) calculation of the overall density of Jupiter 
C) detection of methane (CH4) in the atmosphere 
D) detection of ammonia (NH3) in the atmosphere

Question 11

A satellite of a hypothetical ringed planet has an orbital period of 120 hours. Ring particles with each of the following periods would experience an effective resonance with this satellite EXCEPT one. Which period would NOT produce an effective resonance?

Accepted Answer

A) 30 hours 
B) 51 hours 
C) 60 hours 
D) 80 hours 
A) 30 hours 
B) 51 hours 
C) 60 hours 
D) 80 hours

Question 12

The composition of Jupiter's clouds is:

Accepted Answer

A) liquid droplets of water and ammonia. 
B) ice crystals of water, ammonium hydrosulfide, and carbon dioxide. 
C) water-ice crystals. 
D) ice crystals of ammonia, ammonium hydrosulfide, and water. 
A) liquid droplets of water and ammonia. 
B) ice crystals of water, ammonium hydrosulfide, and carbon dioxide. 
C) water-ice crystals. 
D) ice crystals of ammonia, ammonium hydrosulfide, and water.

Question 13

The white spots observed in Saturn's atmosphere are believed to be crystals of:

Accepted Answer

A) ammonia. 
B) water vapor. 
C) methane. 
D) hydrogen. 
A) ammonia. 
B) water vapor. 
C) methane. 
D) hydrogen.

Question 14

The mean thickness of Saturn's rings is now thought to be:

Accepted Answer

A) a few tens of meters. 
B) a few kilometers. 
C) a few thousand meters. 
D) about 10,000 m. 
A) a few tens of meters. 
B) a few kilometers. 
C) a few thousand meters. 
D) about 10,000 m.

Question 15

The material in the interiors of Jupiter and Saturn thought to be responsible for their powerful magnetic fields is:

Accepted Answer

A) molten iron and nickel. 
B) liquid metallic hydrogen. 
C) gases of NH3 (ammonia), CH4 (methane), and H2O (water vapor). 
D) solid magnetic iron. 
A) molten iron and nickel. 
B) liquid metallic hydrogen. 
C) gases of NH3 (ammonia), CH4 (methane), and H2O (water vapor). 
D) solid magnetic iron.

Question 16

How do we know the nature of the brown ovals in Jupiter's atmosphere?

Accepted Answer

A) They glow brightly in infrared, thus we know they are warm, high-altitude clouds. 
B) They glow brightly in infrared, thus we know they are holes in the atmosphere that allow the escape of infrared from warmer, deeper layers. 
C) The brown color matches other features at that level, so we know they form a continuous part of that atmospheric layer. 
D) They glow dimly in infrared, thus we know they are actually at higher, colder levels in the atmosphere. 
A) They glow brightly in infrared, thus we know they are warm, high-altitude clouds. 
B) They glow brightly in infrared, thus we know they are holes in the atmosphere that allow the escape of infrared from warmer, deeper layers. 
C) The brown color matches other features at that level, so we know they form a continuous part of that atmospheric layer. 
D) They glow dimly in infrared, thus we know they are actually at higher, colder levels in the atmosphere.

Question 17

Hydrogen and helium are the major constituents of Jupiter, but they proved hard to detect. Which one of the following was NOT a reason for this difficulty?

Accepted Answer

A) The spectral signatures of these molecules contain few prominent visible lines. 
B) Ultraviolet radiation is absorbed in Earth's atmosphere. 
C) Jupiter is always very far away from Earth and from the Sun. 
D) The hydrogen and helium on Jupiter exist only in solid form deep under the atmosphere, and they emit very little radiation. 
A) The spectral signatures of these molecules contain few prominent visible lines. 
B) Ultraviolet radiation is absorbed in Earth's atmosphere. 
C) Jupiter is always very far away from Earth and from the Sun. 
D) The hydrogen and helium on Jupiter exist only in solid form deep under the atmosphere, and they emit very little radiation.

Question 18

Suppose in a particular year the rings of Saturn are seen exactly edge on from Earth. When will the rings appear from Earth to be exactly face on with the plane of the rings perpendicular to our line of sight? (Assume Saturn's orbital period is 30 years.)

Accepted Answer

A) 7.5 years in the future 
B) 15 years in the future 
C) 30 years in the future 
D) never 
A) 7.5 years in the future 
B) 15 years in the future 
C) 30 years in the future 
D) never

Question 19

How and by whom was it first determined that the rings of Saturn must be made up of a myriad of small particles, all separately orbiting Saturn in a wide, flat plane?

Accepted Answer

A) Astronomers at JPL and NASA found from photographs by the Voyager 1 spacecraft that the rings were composed of thousands of tiny ringlets, with particles orbiting even in the Cassini division. 
B) Sir George Airy observed that wave-like brightenings propagated through the rings in the direction of rotation, as could be true only if the rings were composed of interacting particles. 
C) James Keeler observed that the Doppler shift in reflected sunlight increased inward across the rings, whereas if the rings rotated as a solid body the Doppler shift should increase outward. 
D) James Clerk Maxwell calculated that no material could be strong enough to withstand the differential gravitational forces of Saturn on the rings if they were solid. 
A) Astronomers at JPL and NASA found from photographs by the Voyager 1 spacecraft that the rings were composed of thousands of tiny ringlets, with particles orbiting even in the Cassini division. 
B) Sir George Airy observed that wave-like brightenings propagated through the rings in the direction of rotation, as could be true only if the rings were composed of interacting particles. 
C) James Keeler observed that the Doppler shift in reflected sunlight increased inward across the rings, whereas if the rings rotated as a solid body the Doppler shift should increase outward. 
D) James Clerk Maxwell calculated that no material could be strong enough to withstand the differential gravitational forces of Saturn on the rings if they were solid.

Question 20

The outer radius of the Saturnian ring system is about 274,000 km, whereas the outer radius of Jupiter's ring system is about 222,000 km. How does the period of the outermost particles in Jupiter's rings compare with the period of the outermost particles in Saturn's rings?

Accepted Answer

A) For Jupiter the period is about 39% of the period for Saturn. 
B) For Jupiter the period is about 73% of the period for Saturn. 
C) For Jupiter the period is about 81% of the period for Saturn. 
D) For Jupiter the period is about 123% of the period for Saturn. 
A) For Jupiter the period is about 39% of the period for Saturn. 
B) For Jupiter the period is about 73% of the period for Saturn. 
C) For Jupiter the period is about 81% of the period for Saturn. 
D) For Jupiter the period is about 123% of the period for Saturn.

Exam 12: Jupiter and Saturn: Lords of the Planets

Suppose Mimas orbited further out from Saturn than it does now. What difference, if any, would this make to the Cassini division?

The Cassini observations of Jupiter suggest that, contrary to previous models, the light-colored zones on Jupiter are:

Jupiter's mass is more than 300 times the mass of Earth, and Saturn has almost 100 times Earth's mass. These masses were determined by:

Can charged particles from Io affect aurorae on Jupiter?

Jupiter has a magnetic field that is:

The dark-colored belts on Jupiter are brighter than the surrounding regions when viewed in infrared or heat radiation because:

On Jupiter and Saturn the wind currents move generally:

On what planet would you NOT expect to find an aurora?

Jupiter appears as a flattened, oblate spheroid in the sky because:

Each of the following provides evidence for the large amount of hydrogen in the atmosphere of Jupiter EXCEPT one. Which is the exception?

A satellite of a hypothetical ringed planet has an orbital period of 120 hours. Ring particles with each of the following periods would experience an effective resonance with this satellite EXCEPT one. Which period would NOT produce an effective resonance?

The composition of Jupiter's clouds is:

The white spots observed in Saturn's atmosphere are believed to be crystals of:

The mean thickness of Saturn's rings is now thought to be:

The material in the interiors of Jupiter and Saturn thought to be responsible for their powerful magnetic fields is:

How do we know the nature of the brown ovals in Jupiter's atmosphere?

Hydrogen and helium are the major constituents of Jupiter, but they proved hard to detect. Which one of the following was NOT a reason for this difficulty?

Suppose in a particular year the rings of Saturn are seen exactly edge on from Earth. When will the rings appear from Earth to be exactly face on with the plane of the rings perpendicular to our line of sight? (Assume Saturn's orbital period is 30 years.)

How and by whom was it first determined that the rings of Saturn must be made up of a myriad of small particles, all separately orbiting Saturn in a wide, flat plane?

The outer radius of the Saturnian ring system is about 274,000 km, whereas the outer radius of Jupiter's ring system is about 222,000 km. How does the period of the outermost particles in Jupiter's rings compare with the period of the outermost particles in Saturn's rings?

Astronomy and the Universe

Knowing the Heavens

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

The Nature of Light

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Asteroids, Comets, and Impacts

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Cosmology: The Origin and Evolution of the Universe

Exploring the Early Universe

The Search for Extraterrestrial Life

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