Question 1

How does the thickness of Saturn's bright ring system compare to its diameter?

Accepted Answer

A)  It's about 10 times thinner. 
B)  It's about 1,000 times thinner. 
C)  It's about 10,000 times thinner. 
D)  It's about 100,000 times thinner. 
E)  It's about 10 million times thinner. 
A)  It's about 10 times thinner. 
B)  It's about 1,000 times thinner. 
C)  It's about 10,000 times thinner. 
D)  It's about 100,000 times thinner. 
E)  It's about 10 million times thinner. E

Question 2

From where does Titan's thick, nitrogen-rich atmosphere likely arise?

Accepted Answer

A)  photodissociation of methane and ammonia in its atmosphere 
B)  It is emitted by frequent volcanic eruptions. 
C)  It has been deposited by ongoing cometary impacts over the age of the Solar System. 
D)  photosynthesis of algae in oceans that lie beneath its icy surface 
E)  It was released from underground reservoirs by early impacts. 
A)  photodissociation of methane and ammonia in its atmosphere 
B)  It is emitted by frequent volcanic eruptions. 
C)  It has been deposited by ongoing cometary impacts over the age of the Solar System. 
D)  photosynthesis of algae in oceans that lie beneath its icy surface 
E)  It was released from underground reservoirs by early impacts. A

Question 3

How many moons are known in the Solar System?

Accepted Answer

A)  less than 50 
B)  at least 150 
C)  around 10 
D)  many thousands 
E)  several million 
A)  less than 50 
B)  at least 150 
C)  around 10 
D)  many thousands 
E)  several million B

Question 4

Why does the Adams Ring around Neptune clump into arcs rather than uniform rings?

Accepted Answer

It is believed that gravitational forces

Question 5

Titan is a high-priority candidate for the search for life outside Earth primarily because it has

Accepted Answer

A)  liquid water on its surface. 
B)  an oxygen atmosphere like Earth's. 
C)  warm temperatures. 
D)  active lava volcanoes. 
E)  organic material. 
A)  liquid water on its surface. 
B)  an oxygen atmosphere like Earth's. 
C)  warm temperatures. 
D)  active lava volcanoes. 
E)  organic material.

Question 6

Astronomers originally planned to have the Pioneer 11 space probe pass through the Cassini Gap in Saturn's rings.Would this have been completely safe?

Accepted Answer

A)  Yes, but they decided that it was more important to observe Saturn's moons. 
B)  Yes, but they decided to land on the rings instead. 
C)  No, because the Cassini Gap is too narrow. 
D)  No, because the Cassini Gap is not completely empty. 
E)  No, because the same gravitational influences that create the Cassini Gap would have destroyed the probe. 
A)  Yes, but they decided that it was more important to observe Saturn's moons. 
B)  Yes, but they decided to land on the rings instead. 
C)  No, because the Cassini Gap is too narrow. 
D)  No, because the Cassini Gap is not completely empty. 
E)  No, because the same gravitational influences that create the Cassini Gap would have destroyed the probe.

Question 7

Saturn's G ring, as shown in the figure below, is known as

Accepted Answer

A)  a ringlet. 
B)  an arclet. 
C)  a diffuse ring. 
D)  a spoke. 
E)  a crepe ring. 
A)  a ringlet. 
B)  an arclet. 
C)  a diffuse ring. 
D)  a spoke. 
E)  a crepe ring.

Question 8

If a moon has a retrograde orbit, then it orbits

Accepted Answer

A)  in the direction opposite that of the planet's rotation. 
B)  in the opposite direction than its planet revolves around the Sun. 
C)  the Sun at a greater distance than the planet. 
D)  with an unusually high velocity. 
E)  None of these is true. 
A)  in the direction opposite that of the planet's rotation. 
B)  in the opposite direction than its planet revolves around the Sun. 
C)  the Sun at a greater distance than the planet. 
D)  with an unusually high velocity. 
E)  None of these is true.

Question 9

What material has been seen erupting from the surface of the icy moon Enceladus, and why?

Accepted Answer

Geysers of water erupt from th

Question 10

Rings of giant planets are very thin compared to their diameters mainly because

Accepted Answer

A)  of collisions between ring particles. 
B)  moons that tidally disrupt have small diameters. 
C)  energy is conserved when a moon tidally disrupts. 
D)  the planets have large tidal forces. 
E)  shepherd moons force them to be extremely thin. 
A)  of collisions between ring particles. 
B)  moons that tidally disrupt have small diameters. 
C)  energy is conserved when a moon tidally disrupts. 
D)  the planets have large tidal forces. 
E)  shepherd moons force them to be extremely thin.

Question 11

Why are some moons such as Io and Enceladus geologically active even though they are small in size compared to the planets?

Accepted Answer

A)  Unlike some planets, these moons have additional supplies of radioactive elements providing the necessary heating to drive geological activity. 
B)  The interiors of these moons contain a larger supply of heavy elements such as iron than is found in terrestrial planets, which contributes to greater heating and high geological activity. 
C)  Tidal forces from the Sun are especially large for these moons, leading to greater interior heating and more geological activity. 
D)  Tidal forces from the parent planet heat the interiors of these moons, resulting in geological activity. 
E)  None of these; it is still a mystery. 
A)  Unlike some planets, these moons have additional supplies of radioactive elements providing the necessary heating to drive geological activity. 
B)  The interiors of these moons contain a larger supply of heavy elements such as iron than is found in terrestrial planets, which contributes to greater heating and high geological activity. 
C)  Tidal forces from the Sun are especially large for these moons, leading to greater interior heating and more geological activity. 
D)  Tidal forces from the parent planet heat the interiors of these moons, resulting in geological activity. 
E)  None of these; it is still a mystery.

Question 12

The mass of all of Saturn's bright rings is comparable to the mass of

Accepted Answer

A)  a small comet. 
B)  a small icy moon. 
C)  Earth's Moon. 
D)  Mars. 
E)  Venus. 
A)  a small comet. 
B)  a small icy moon. 
C)  Earth's Moon. 
D)  Mars. 
E)  Venus.

Question 13

Jupiter's rings are made of material from

Accepted Answer

A)  its innermost moons. 
B)  its upper atmosphere. 
C)  its outermost moons. 
D)  only Io. 
E)  only its retrograde moons. 
A)  its innermost moons. 
B)  its upper atmosphere. 
C)  its outermost moons. 
D)  only Io. 
E)  only its retrograde moons.

Question 14

Based on the figure below, this moon

Accepted Answer

A)  is geologically active. 
B)  is possibly geologically active. 
C)  was geologically active in the past but is no longer active. 
D)  is geologically dead. 
E)  More information is needed before any conclusion can be made. 
A)  is geologically active. 
B)  is possibly geologically active. 
C)  was geologically active in the past but is no longer active. 
D)  is geologically dead. 
E)  More information is needed before any conclusion can be made.

Question 15

Ring particles range in size from tiny grains to

Accepted Answer

A)  house-sized boulders. 
B)  basketball-sized boulders. 
C)  city-sized chunks. 
D)  tennis ball-sized rocks. 
E)  fingernail-sized pebbles. 
A)  house-sized boulders. 
B)  basketball-sized boulders. 
C)  city-sized chunks. 
D)  tennis ball-sized rocks. 
E)  fingernail-sized pebbles.

Question 16

By studying the orbit of a moon around its parent planet, astronomers can use ________ to find the parent planet's ________.

Accepted Answer

A)  escape velocity; rotation rate 
B)  the moon's eccentricity; Roche limit 
C)  small perturbations; magnetic field strength 
D)  the moon's velocity; radius 
E)  Newton's version of Kepler's third law; mass 
A)  escape velocity; rotation rate 
B)  the moon's eccentricity; Roche limit 
C)  small perturbations; magnetic field strength 
D)  the moon's velocity; radius 
E)  Newton's version of Kepler's third law; mass

Question 17

What is the most likely reason that a planet's rings would reflect more than 50 percent of the sunlight they receive?

Accepted Answer

A)  They are made of ice. 
B)  They are made of silicate rock. 
C)  They are made of liquid. 
D)  They are made of iron. 
E)  They are very old. 
A)  They are made of ice. 
B)  They are made of silicate rock. 
C)  They are made of liquid. 
D)  They are made of iron. 
E)  They are very old.

Question 18

On which of Saturn's moons did the Cassini-Huygens Probe land in 2004, providing our first view of the varied and active surface?

Accepted Answer

A)  Callisto 
B)  Io 
C)  Europa 
D)  Enceladus 
E)  Titan 
A)  Callisto 
B)  Io 
C)  Europa 
D)  Enceladus 
E)  Titan

Question 19

Why is Io, a moon that is smaller and farther from the Sun than our own Moon, still geologically active?

Accepted Answer

Tidal stresses from Jupiter co

Question 20

The semimajor axis of Iapetus's orbit around Saturn is approximately 3.56 * 106 km, and its orbital period is approximately 79 days.Use these data and Newton's version of Kepler's third law to calculate the mass of Saturn.

Accepted Answer

The Newtonian version of Kepler's third

Exam 11: Planetary Moons and Rings

How does the thickness of Saturn's bright ring system compare to its diameter?

From where does Titan's thick, nitrogen-rich atmosphere likely arise?

How many moons are known in the Solar System?

Why does the Adams Ring around Neptune clump into arcs rather than uniform rings?

Titan is a high-priority candidate for the search for life outside Earth primarily because it has

Astronomers originally planned to have the Pioneer 11 space probe pass through the Cassini Gap in Saturn's rings.Would this have been completely safe?

Saturn's G ring, as shown in the figure below, is known as

If a moon has a retrograde orbit, then it orbits

What material has been seen erupting from the surface of the icy moon Enceladus, and why?

Rings of giant planets are very thin compared to their diameters mainly because

Why are some moons such as Io and Enceladus geologically active even though they are small in size compared to the planets?

The mass of all of Saturn's bright rings is comparable to the mass of

Jupiter's rings are made of material from

Based on the figure below, this moon

Ring particles range in size from tiny grains to

By studying the orbit of a moon around its parent planet, astronomers can use ________ to find the parent planet's ________.

What is the most likely reason that a planet's rings would reflect more than 50 percent of the sunlight they receive?

On which of Saturn's moons did the Cassini-Huygens Probe land in 2004, providing our first view of the varied and active surface?

Why is Io, a moon that is smaller and farther from the Sun than our own Moon, still geologically active?

The semimajor axis of Iapetus's orbit around Saturn is approximately 3.56 * 106 km, and its orbital period is approximately 79 days.Use these data and Newton's version of Kepler's third law to calculate the mass of Saturn.

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Formation of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquidthe Giant Planets

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

The Interstellar Medium and Star Formation

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

Galaxies

The Milky Waya Normal Spiral Galaxy

The Expanding Universe

Cosmology

Large-Scale Structure in the Universe

Life

Filters

By studying the orbit of a moon around its parent planet, astronomers can use to find the parent planet's .

The semimajor axis of Iapetus's orbit around Saturn is approximately 3.56 * 10⁶ km, and its orbital period is approximately 79 days.Use these data and Newton's version of Kepler's third law to calculate the mass of Saturn.