Question 1

What is the diameter of the Moon compared with the diameter of Earth?

Accepted Answer

A)  about 1/4 of the diameter of Earth 
B)  less than 1/100 of the diameter of Earth 
C)  about 1/10 of the diameter of Earth 
D)  just over 1/2 the diameter of Earth 
A)  about 1/4 of the diameter of Earth 
B)  less than 1/100 of the diameter of Earth 
C)  about 1/10 of the diameter of Earth 
D)  just over 1/2 the diameter of Earth

Question 2

Which of these is NOT a contributor to librations, the "nodding" back and forth of the Moon that allows observers on Earth to see more than half of it?

Accepted Answer

A)  The Moon's rotation axis is not perpendicular to its orbital plane. 
B)  The Moon's orbit around Earth and the ecliptic are not the same plane. 
C)  The Moon is not always the same distance from Earth. 
D)  Earth does not move at a steady rate in its orbit about the Sun. 
A)  The Moon's rotation axis is not perpendicular to its orbital plane. 
B)  The Moon's orbit around Earth and the ecliptic are not the same plane. 
C)  The Moon is not always the same distance from Earth. 
D)  Earth does not move at a steady rate in its orbit about the Sun.

Question 3

What process created the lunar regolith?

Accepted Answer

A)  successive cracking and shattering of lunar rocks by very rapid and extreme temperature changes throughout the Moon's history 
B)  cracking and pulverizing by meteoric bombardment 
C)  billions of years of the alternating freezing and thawing of subsurface water 
D)  continuous erosion by charged particles in the solar wind 
A)  successive cracking and shattering of lunar rocks by very rapid and extreme temperature changes throughout the Moon's history 
B)  cracking and pulverizing by meteoric bombardment 
C)  billions of years of the alternating freezing and thawing of subsurface water 
D)  continuous erosion by charged particles in the solar wind

Question 4

What is the basic structure of Earth's atmosphere?

Accepted Answer

A)  single layer of smoothly decreasing temperature with increasing altitude 
B)  four layers of alternating temperature profiles: temperature decreasing, then increasing, then decreasing, then increasing with altitude 
C)  single layer of smoothly increasing temperature with increasing altitude 
D)  two layers: temperature decreasing with increasing altitude in the lower layer, then increasing with increasing altitude in the upper layer 
A)  single layer of smoothly decreasing temperature with increasing altitude 
B)  four layers of alternating temperature profiles: temperature decreasing, then increasing, then decreasing, then increasing with altitude 
C)  single layer of smoothly increasing temperature with increasing altitude 
D)  two layers: temperature decreasing with increasing altitude in the lower layer, then increasing with increasing altitude in the upper layer

Question 5

What is the cause of the great mountain ranges on Earth, such as the Rockies, the Andes, and the Himalayas?

Accepted Answer

A)  In the carving of continents during ice ages, the mountains were left behind as "islands" in a sea of glaciers. 
B)  Heat from Earth's interior caused Earth's crust to expand and then crumple. 
C)  Two tectonic plates are being pushed apart by molten rock that is being forced up between them. 
D)  Two tectonic plates that are moving at different velocities across the face of Earth collide. 
A)  In the carving of continents during ice ages, the mountains were left behind as "islands" in a sea of glaciers. 
B)  Heat from Earth's interior caused Earth's crust to expand and then crumple. 
C)  Two tectonic plates are being pushed apart by molten rock that is being forced up between them. 
D)  Two tectonic plates that are moving at different velocities across the face of Earth collide.

Question 6

Why does the ejecta blanket around some lunar craters appear light-colored?

Accepted Answer

A)  These craters are relatively young and have not yet been contaminated and made darker by incoming material. 
B)  The impact punched through the lunar crust and released lighter magma from the Moon's molten mantle. 
C)  The craters are relatively old. 
D)  The incoming projectile was composed of lighter material and colored the Moon's surface. 
A)  These craters are relatively young and have not yet been contaminated and made darker by incoming material. 
B)  The impact punched through the lunar crust and released lighter magma from the Moon's molten mantle. 
C)  The craters are relatively old. 
D)  The incoming projectile was composed of lighter material and colored the Moon's surface.

Question 7

To what does the name "Pangaea" refer?

Accepted Answer

A)  tectonic plate on which most of North America is riding 
B)  outer life-bearing layer of Earth, including the soil, oceans, and atmosphere 
C)  supercontinent on a tectonic plate that split into the present North America, South America, Europe, and Africa 
D)  ocean that covered most of North America millions of years ago 
A)  tectonic plate on which most of North America is riding 
B)  outer life-bearing layer of Earth, including the soil, oceans, and atmosphere 
C)  supercontinent on a tectonic plate that split into the present North America, South America, Europe, and Africa 
D)  ocean that covered most of North America millions of years ago

Question 8

The outer core of Earth is molten, but the inner core is solid. The reason is that the

Accepted Answer

A)  inner core has a different composition than the outer core, with a higher melting point. 
B)  lower pressure in the inner core allows the material to freeze out of the molten rock. 
C)  melting point of the iron-nickel mixture is raised above the actual temperature by the extremely high pressure. 
D)  temperature is lower in the inner core than in the surrounding region. 
A)  inner core has a different composition than the outer core, with a higher melting point. 
B)  lower pressure in the inner core allows the material to freeze out of the molten rock. 
C)  melting point of the iron-nickel mixture is raised above the actual temperature by the extremely high pressure. 
D)  temperature is lower in the inner core than in the surrounding region.

Question 9

How do the near and far sides of the Moon compare?

Accepted Answer

A)  Both sides are quite similar to each other-each side has several large mare, or "seas," surrounded by heavily cratered terrain. 
B)  The near side has extensive, heavily cratered regions between and around the smooth maria, or "seas," whereas the far side is almost entirely covered with maria. 
C)  It is not known; the far side is hidden in perpetual darkness. 
D)  The near side has several large maria, or "seas," whereas the far side has only a few small maria. 
A)  Both sides are quite similar to each other-each side has several large mare, or "seas," surrounded by heavily cratered terrain. 
B)  The near side has extensive, heavily cratered regions between and around the smooth maria, or "seas," whereas the far side is almost entirely covered with maria. 
C)  It is not known; the far side is hidden in perpetual darkness. 
D)  The near side has several large maria, or "seas," whereas the far side has only a few small maria.

Question 10

The Apollo astronauts dated many types of lunar rocks. Which of these is the oldest?

Accepted Answer

A)  anorthosite 
B)  Lava 
C)  impact breccia 
D)  mare basalt 
A)  anorthosite 
B)  Lava 
C)  impact breccia 
D)  mare basalt

Question 11

Why do the maria have few craters in them?

Accepted Answer

A)  The maria are ancient sea beds. During the heaviest bombardment they were filled with water, and the meteoroids were broken up by the water, doing little damage to the maria themselves. 
B)  The maria are surfaced with hard basalt. Impacts mostly bounce off or break apart without making a crater. 
C)  The basalt that fills the maria has a low melting temperature. An impact will melt it, and it flows immediately to obliterate the crater. 
D)  There has been relatively little cratering activity since the maria were formed. 
A)  The maria are ancient sea beds. During the heaviest bombardment they were filled with water, and the meteoroids were broken up by the water, doing little damage to the maria themselves. 
B)  The maria are surfaced with hard basalt. Impacts mostly bounce off or break apart without making a crater. 
C)  The basalt that fills the maria has a low melting temperature. An impact will melt it, and it flows immediately to obliterate the crater. 
D)  There has been relatively little cratering activity since the maria were formed.

Question 12

Which one of these statements about ozone is NOT correct?

Accepted Answer

A)  It is triple oxygen, O3. 
B)  It comprises most of Earth's stratosphere. 
C)  It absorbs intermediate wavelength ultraviolet radiation from the Sun. 
D)  It causes the temperature in the stratosphere to rise with altitude. 
A)  It is triple oxygen, O3. 
B)  It comprises most of Earth's stratosphere. 
C)  It absorbs intermediate wavelength ultraviolet radiation from the Sun. 
D)  It causes the temperature in the stratosphere to rise with altitude.

Question 13

Why is the Moon in a synchronous orbit around Earth, always keeping the same face toward Earth?

Accepted Answer

A)  There is a strong magnetic attraction between the two bodies that keeps the Moon turned toward Earth. 
B)  The Moon must rotate on its axis at the same rate it orbits Earth to conserve angular momentum. 
C)  As the Moon rotates, friction between the Moon's large liquid interior and its mantle has slowed the rate of rotation until it just matches the orbital rate. Over time it will slow further, and then the Moon will no longer be in a synchronous orbit. 
D)  When the Moon was molten and experienced chemical differentiation, the gravitational pull of Earth caused large tides. The friction created as Earth's gravity attempted to keep the high tide bulge pointed toward Earth resulted in the Moon's rotation being slowed, causing it always to face Earth. 
A)  There is a strong magnetic attraction between the two bodies that keeps the Moon turned toward Earth. 
B)  The Moon must rotate on its axis at the same rate it orbits Earth to conserve angular momentum. 
C)  As the Moon rotates, friction between the Moon's large liquid interior and its mantle has slowed the rate of rotation until it just matches the orbital rate. Over time it will slow further, and then the Moon will no longer be in a synchronous orbit. 
D)  When the Moon was molten and experienced chemical differentiation, the gravitational pull of Earth caused large tides. The friction created as Earth's gravity attempted to keep the high tide bulge pointed toward Earth resulted in the Moon's rotation being slowed, causing it always to face Earth.

Question 14

In the modern theory of crustal motion on Earth's surface, the process of seafloor spreading is described as the

Accepted Answer

A)  motion of plates toward mid-oceanic ridges and away from continental boundaries. 
B)  motion of plates away from mid-oceanic ridges and toward continental boundaries. 
C)  northward motion of some plates and the southward motion of others, causing earthquakes where they slide past each other. 
D)  rotation of plates around axes that remain stationary on Earth causing plate-edge collisions. 
A)  motion of plates toward mid-oceanic ridges and away from continental boundaries. 
B)  motion of plates away from mid-oceanic ridges and toward continental boundaries. 
C)  northward motion of some plates and the southward motion of others, causing earthquakes where they slide past each other. 
D)  rotation of plates around axes that remain stationary on Earth causing plate-edge collisions.

Question 15

What appears to be the "impact history" of cratering on the Moon?

Accepted Answer

A)  more or less constant bombardment from the earliest times to the present 
B)  short periods of heavy bombardment alternating with long periods of light bombardment throughout the Moon's life 
C)  heaviest bombardment when the Moon first formed, gradually decreasing to light bombardment today 
D)  early period of heavy bombardment, then very light bombardment to the present 
A)  more or less constant bombardment from the earliest times to the present 
B)  short periods of heavy bombardment alternating with long periods of light bombardment throughout the Moon's life 
C)  heaviest bombardment when the Moon first formed, gradually decreasing to light bombardment today 
D)  early period of heavy bombardment, then very light bombardment to the present

Question 16

Earth's thermosphere is the

Accepted Answer

A)  outermost atmospheric layer in which ultraviolet light from the Sun ionizes atoms. 
B)  intermediate atmospheric layer in which ultraviolet light from the Sun is absorbed by ozone (O3) molecules. 
C)  region of the magnetosphere in which trapped high-energy charged particles spiral along magnetic field lines. 
D)  layer of molten iron and nickel below the mantle. 
A)  outermost atmospheric layer in which ultraviolet light from the Sun ionizes atoms. 
B)  intermediate atmospheric layer in which ultraviolet light from the Sun is absorbed by ozone (O3) molecules. 
C)  region of the magnetosphere in which trapped high-energy charged particles spiral along magnetic field lines. 
D)  layer of molten iron and nickel below the mantle.

Question 17

Which one of these four theories about the origin of the Moon is now believed to be correct?

Accepted Answer

A)  Earth and the Moon formed together, already orbiting each other. 
B)  The Moon formed separately in a different part of the solar nebula and was later captured by Earth. 
C)  Earth was spinning so rapidly while still molten that a piece spun off to form the Moon. 
D)  A single large object or set of smaller objects crashed into Earth, and debris from the collision formed the Moon. 
A)  Earth and the Moon formed together, already orbiting each other. 
B)  The Moon formed separately in a different part of the solar nebula and was later captured by Earth. 
C)  Earth was spinning so rapidly while still molten that a piece spun off to form the Moon. 
D)  A single large object or set of smaller objects crashed into Earth, and debris from the collision formed the Moon.

Question 18

The human exploration of the surface of the Moon during the Apollo program lasted

Accepted Answer

A)  less than a year. 
B)  about 25 years. 
C)  about 10 years. 
D)  less than 4 years. 
A)  less than a year. 
B)  about 25 years. 
C)  about 10 years. 
D)  less than 4 years.

Question 19

Earth's magnetic field protects Earth and its inhabitants from

Accepted Answer

A)  the high-energy cosmic rays or hydrogen nuclei moving through the universe. 
B)  the majority of tiny but high-speed micrometeorites, which otherwise would crater Earth and cause significant damage to property. 
C)  a significant proportion of the solar neutrinos, the enormous flux of which could otherwise produce damage to genetic material in life-forms. 
D)  the solar wind, which would otherwise irradiate and damage life-forms if not deflected. 
A)  the high-energy cosmic rays or hydrogen nuclei moving through the universe. 
B)  the majority of tiny but high-speed micrometeorites, which otherwise would crater Earth and cause significant damage to property. 
C)  a significant proportion of the solar neutrinos, the enormous flux of which could otherwise produce damage to genetic material in life-forms. 
D)  the solar wind, which would otherwise irradiate and damage life-forms if not deflected.

Question 20

The Moon is being pulled forward by Earth's tidal bulge. What motion results from this?

Accepted Answer

A)  The pull increases the Moon's energy, causing it to move into a more distant orbit where it moves more slowly. 
B)  The pull increases the Moon's energy, causing it to move into a more distant orbit where it moves more rapidly. 
C)  The pull increases the speed of the Moon. This places it in an orbit closer to Earth as required by Kepler's third law. 
D)  The pull decreases the speed of the Moon. This places it in an orbit farther from Earth, as required by Kepler's third law. 
A)  The pull increases the Moon's energy, causing it to move into a more distant orbit where it moves more slowly. 
B)  The pull increases the Moon's energy, causing it to move into a more distant orbit where it moves more rapidly. 
C)  The pull increases the speed of the Moon. This places it in an orbit closer to Earth as required by Kepler's third law. 
D)  The pull decreases the speed of the Moon. This places it in an orbit farther from Earth, as required by Kepler's third law.

What is the diameter of the Moon compared with the diameter of Earth?

Which of these is NOT a contributor to librations, the "nodding" back and forth of the Moon that allows observers on Earth to see more than half of it?

What process created the lunar regolith?

What is the basic structure of Earth's atmosphere?

What is the cause of the great mountain ranges on Earth, such as the Rockies, the Andes, and the Himalayas?

Why does the ejecta blanket around some lunar craters appear light-colored?

To what does the name "Pangaea" refer?

The outer core of Earth is molten, but the inner core is solid. The reason is that the

How do the near and far sides of the Moon compare?

The Apollo astronauts dated many types of lunar rocks. Which of these is the oldest?

Why do the maria have few craters in them?

Which one of these statements about ozone is NOT correct?

Why is the Moon in a synchronous orbit around Earth, always keeping the same face toward Earth?

In the modern theory of crustal motion on Earth's surface, the process of seafloor spreading is described as the

What appears to be the "impact history" of cratering on the Moon?

Earth's thermosphere is the

Which one of these four theories about the origin of the Moon is now believed to be correct?

The human exploration of the surface of the Moon during the Apollo program lasted

Earth's magnetic field protects Earth and its inhabitants from

The Moon is being pulled forward by Earth's tidal bulge. What motion results from this?

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Atomic Physics and Spectra

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Galaxies

Quasars and Other Active Galaxies

Cosmology

Astrobiology

Filters

Exam 7: Earth and the Moon

What is the diameter of the Moon compared with the diameter of Earth?

Which of these is NOT a contributor to librations, the "nodding" back and forth of the Moon that allows observers on Earth to see more than half of it?

What process created the lunar regolith?

What is the basic structure of Earth's atmosphere?

What is the cause of the great mountain ranges on Earth, such as the Rockies, the Andes, and the Himalayas?

Why does the ejecta blanket around some lunar craters appear light-colored?

To what does the name "Pangaea" refer?

The outer core of Earth is molten, but the inner core is solid. The reason is that the

How do the near and far sides of the Moon compare?

The Apollo astronauts dated many types of lunar rocks. Which of these is the oldest?

Why do the maria have few craters in them?

Which one of these statements about ozone is NOT correct?

Why is the Moon in a synchronous orbit around Earth, always keeping the same face toward Earth?

In the modern theory of crustal motion on Earth's surface, the process of seafloor spreading is described as the

What appears to be the "impact history" of cratering on the Moon?

Earth's thermosphere is the

Which one of these four theories about the origin of the Moon is now believed to be correct?

The human exploration of the surface of the Moon during the Apollo program lasted

Earth's magnetic field protects Earth and its inhabitants from

The Moon is being pulled forward by Earth's tidal bulge. What motion results from this?

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Atomic Physics and Spectra

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Galaxies

Quasars and Other Active Galaxies

Cosmology

Astrobiology

Filters