Question 1

What is believed to be the composition of Earth's core?

Accepted Answer

A)  about 80% iron and 20% lighter elements 
B)  about 20% iron and 80% lighter elements 
C)  about half iron and half lighter elements 
D)  essentially pure iron 
A)  about 80% iron and 20% lighter elements 
B)  about 20% iron and 80% lighter elements 
C)  about half iron and half lighter elements 
D)  essentially pure iron

Question 2

Most of Earth's earthquakes occur:

Accepted Answer

A)  where crustal plates are colliding, separating, or sliding past one another. 
B)  only where crustal plates are colliding head-on. 
C)  only where crustal plates are sliding past each other, as in the San Andreas fault. 
D)  more or less evenly over the entire surface of the planet. 
A)  where crustal plates are colliding, separating, or sliding past one another. 
B)  only where crustal plates are colliding head-on. 
C)  only where crustal plates are sliding past each other, as in the San Andreas fault. 
D)  more or less evenly over the entire surface of the planet.

Question 3

We know that water exists on Mars,but where and in what state does it NOT exist on this planet?

Accepted Answer

A)  flowing in river valleys 
B)  in polar icecaps 
C)  as water vapor in the atmosphere and as clouds 
D)  in permafrost below the surface 
A)  flowing in river valleys 
B)  in polar icecaps 
C)  as water vapor in the atmosphere and as clouds 
D)  in permafrost below the surface

Question 4

The source of the auroras (northern/southern lights)on Earth is:

Accepted Answer

A)  the natural decay of radioactive elements. 
B)  the reflection of sunlight off the polar ice sheets. 
C)  small meteorites burning up in Earth's atmosphere. 
D)  charged particles trapped by Earth's magnetic field interacting with the atmosphere. 
A)  the natural decay of radioactive elements. 
B)  the reflection of sunlight off the polar ice sheets. 
C)  small meteorites burning up in Earth's atmosphere. 
D)  charged particles trapped by Earth's magnetic field interacting with the atmosphere.

Question 5

According to the collision-ejection theory,when was the Moon formed?

Accepted Answer

A)  very early, before Earth's interior differentiated 
B)  after the Era of Heavy Bombardment 
C)  about 60 to 100 million years after the solar system began to form 
D)  within the past billion years 
A)  very early, before Earth's interior differentiated 
B)  after the Era of Heavy Bombardment 
C)  about 60 to 100 million years after the solar system began to form 
D)  within the past billion years

Question 6

At opposition,when Mars comes relatively close to Earth,where would it be seen in the sky by an observer in Earth's northern hemisphere?

Accepted Answer

A)  high in the south at sunset 
B)  on the western horizon at midnight 
C)  high in the south at midnight 
D)  high in the north at midnight 
A)  high in the south at sunset 
B)  on the western horizon at midnight 
C)  high in the south at midnight 
D)  high in the north at midnight

Question 7

The smallest planet in our solar system is:

Accepted Answer

A)  Mars. 
B)  Neptune. 
C)  Mercury. 
D)  Venus. 
A)  Mars. 
B)  Neptune. 
C)  Mercury. 
D)  Venus.

Question 8

The planet whose average density is less than that of water is:

Accepted Answer

A)  Neptune. 
B)  Jupiter. 
C)  Earth. 
D)  Saturn. 
A)  Neptune. 
B)  Jupiter. 
C)  Earth. 
D)  Saturn.

Question 9

Mercury is always much closer to the Sun than Venus is,and yet it never appears brighter than Venus,even at maximum brightness.Explain.

Accepted Answer

A)  We never see more than a small fraction of Mercury's illuminated surface because of its orbital path relative to that of Earth; hence, it always appears dark. 
B)  Mercury has a thick atmosphere that impedes reflection from its surface and hence appears dark. 
C)  Mercury has a high albedo, or reflectivity, but it is very small and hence appears relatively dark. 
D)  Mercury is small, has a dark surface, and has no reflecting clouds. 
A)  We never see more than a small fraction of Mercury's illuminated surface because of its orbital path relative to that of Earth; hence, it always appears dark. 
B)  Mercury has a thick atmosphere that impedes reflection from its surface and hence appears dark. 
C)  Mercury has a high albedo, or reflectivity, but it is very small and hence appears relatively dark. 
D)  Mercury is small, has a dark surface, and has no reflecting clouds.

Question 10

Mars has one hemisphere that is at a higher elevation than the other.In this way,it is similar to:

Accepted Answer

A)  Earth. 
B)  the Moon. 
C)  Mercury. 
D)  Venus. 
A)  Earth. 
B)  the Moon. 
C)  Mercury. 
D)  Venus.

Question 11

Which feature has NOT been seen or detected on Mars?

Accepted Answer

A)  advancing and receding polar icecaps 
B)  dust storms 
C)  active volcanoes 
D)  valley fog 
A)  advancing and receding polar icecaps 
B)  dust storms 
C)  active volcanoes 
D)  valley fog

Question 12

The length of a solar "day" (time between successive sunrises)on Venus is:

Accepted Answer

A)  117 days. 
B)  88 days. 
C)  243 days. 
D)  224 days. 
A)  117 days. 
B)  88 days. 
C)  243 days. 
D)  224 days.

Question 13

The mantle of Earth is composed of:

Accepted Answer

A)  atmospheric gases. 
B)  water. 
C)  rock. 
D)  iron. 
A)  atmospheric gases. 
B)  water. 
C)  rock. 
D)  iron.

Question 14

The Moon,because of the tides in Earth's oceans,is:

Accepted Answer

A)  spiraling outward, away from Earth. 
B)  shrinking. 
C)  unaffected and continues to orbit in a constant elliptical path. 
D)  moving slowly toward Earth. 
A)  spiraling outward, away from Earth. 
B)  shrinking. 
C)  unaffected and continues to orbit in a constant elliptical path. 
D)  moving slowly toward Earth.

Question 15

Mercury,unlike the Moon,has extensive plains between craters.The reason is thought to be that:

Accepted Answer

A)  the plains on Mercury are older than the maria on the Moon. Thus, more time has elapsed during which cratering has erased evidence of earlier maria on Mercury. 
B)  older craters have been worn down and obliterated by the solar wind. 
C)  because of its large iron core, Mercury has a thinner mantle and therefore has fewer craters produced by volcanoes. 
D)  Mercury is closer to the Sun and did not receive as many crater-forming impacts as the Moon. 
A)  the plains on Mercury are older than the maria on the Moon. Thus, more time has elapsed during which cratering has erased evidence of earlier maria on Mercury. 
B)  older craters have been worn down and obliterated by the solar wind. 
C)  because of its large iron core, Mercury has a thinner mantle and therefore has fewer craters produced by volcanoes. 
D)  Mercury is closer to the Sun and did not receive as many crater-forming impacts as the Moon.

Question 16

The lower atmosphere of Venus near the surface can be described as:

Accepted Answer

A)  clear. 
B)  foggy. 
C)  very dusty. 
D)  absent (Venus has almost no atmosphere!). 
A)  clear. 
B)  foggy. 
C)  very dusty. 
D)  absent (Venus has almost no atmosphere!).

Question 17

The interior of Mercury contains:

Accepted Answer

A)  significant amounts of water as permafrost because occasional melting has produced deep water-formed valleys that criss-cross the planet's surface. 
B)  mostly ices and very low-density material because the planet's average density is close to that of water. 
C)  an iron core that occupies a large fraction of the volume of the overall planet and produces a magnetic field. 
D)  very little iron, in contrast with Earth, and so the planet has no magnetic field. 
A)  significant amounts of water as permafrost because occasional melting has produced deep water-formed valleys that criss-cross the planet's surface. 
B)  mostly ices and very low-density material because the planet's average density is close to that of water. 
C)  an iron core that occupies a large fraction of the volume of the overall planet and produces a magnetic field. 
D)  very little iron, in contrast with Earth, and so the planet has no magnetic field.

Question 18

Auroras on Earth are caused by:

Accepted Answer

A)  the reflection of sunlight from the Arctic and Antarctic ice into the polar skies. 
B)  electrons accelerated by electric currents in the ionosphere and then deposited into Earth's atmosphere. 
C)  high-energy charged particles from the magnetosphere guided by Earth's magnetic field into polar regions of the atmosphere. 
D)  ultraviolet radiation from the Sun exciting and ionizing atoms in Earth's upper atmosphere to emit characteristic colors of light. 
A)  the reflection of sunlight from the Arctic and Antarctic ice into the polar skies. 
B)  electrons accelerated by electric currents in the ionosphere and then deposited into Earth's atmosphere. 
C)  high-energy charged particles from the magnetosphere guided by Earth's magnetic field into polar regions of the atmosphere. 
D)  ultraviolet radiation from the Sun exciting and ionizing atoms in Earth's upper atmosphere to emit characteristic colors of light.

Question 19

The long and high mountain ranges found in the centers of several major oceans on Earth,such as the Mid-Atlantic Ridge,are caused by:

Accepted Answer

A)  continuous and steady erosion of the seabed on either side of the mountains by powerful sea currents flowing across the oceans, such as the Gulf Stream in the Atlantic. 
B)  lava upflow as the tectonic plates on the seafloor split apart and separate. 
C)  rebound of the surface of Earth in the centers of the large craters that became the ocean basins after the impacts of the large planetesimals or asteroids early in Earth's history. 
D)  upthrust and buckling caused by seafloor motions from the continents toward the ocean centers, equivalent to the production of continental mountain ranges such as the Rockies. 
A)  continuous and steady erosion of the seabed on either side of the mountains by powerful sea currents flowing across the oceans, such as the Gulf Stream in the Atlantic. 
B)  lava upflow as the tectonic plates on the seafloor split apart and separate. 
C)  rebound of the surface of Earth in the centers of the large craters that became the ocean basins after the impacts of the large planetesimals or asteroids early in Earth's history. 
D)  upthrust and buckling caused by seafloor motions from the continents toward the ocean centers, equivalent to the production of continental mountain ranges such as the Rockies.

Question 20

The heat energy that powers tectonic activity on the surface of Earth originates deep in Earth's core.How does this energy move from the core to the surface?

Accepted Answer

A)  conduction through the solid lower mantle and convection in the upper mantle 
B)  convection throughout the entire mantle 
C)  conduction throughout the entire mantle 
D)  steady flow of hot magna from Earth's core through cracks in the mantle to the lithosphere 
A)  conduction through the solid lower mantle and convection in the upper mantle 
B)  convection throughout the entire mantle 
C)  conduction throughout the entire mantle 
D)  steady flow of hot magna from Earth's core through cracks in the mantle to the lithosphere

What is believed to be the composition of Earth's core?

Most of Earth's earthquakes occur:

We know that water exists on Mars,but where and in what state does it NOT exist on this planet?

The source of the auroras (northern/southern lights)on Earth is:

According to the collision-ejection theory,when was the Moon formed?

At opposition,when Mars comes relatively close to Earth,where would it be seen in the sky by an observer in Earth's northern hemisphere?

The smallest planet in our solar system is:

The planet whose average density is less than that of water is:

Mercury is always much closer to the Sun than Venus is,and yet it never appears brighter than Venus,even at maximum brightness.Explain.

Mars has one hemisphere that is at a higher elevation than the other.In this way,it is similar to:

Which feature has NOT been seen or detected on Mars?

The length of a solar "day" (time between successive sunrises)on Venus is:

The mantle of Earth is composed of:

The Moon,because of the tides in Earth's oceans,is:

Mercury,unlike the Moon,has extensive plains between craters.The reason is thought to be that:

The lower atmosphere of Venus near the surface can be described as:

The interior of Mercury contains:

Auroras on Earth are caused by:

The long and high mountain ranges found in the centers of several major oceans on Earth,such as the Mid-Atlantic Ridge,are caused by:

The heat energy that powers tectonic activity on the surface of Earth originates deep in Earth's core.How does this energy move from the core to the surface?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

Characterizing Stars

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters

Exam 6: The Terrestrial Planets and Their Moons

What is believed to be the composition of Earth's core?

Most of Earth's earthquakes occur:

We know that water exists on Mars,but where and in what state does it NOT exist on this planet?

The source of the auroras (northern/southern lights)on Earth is:

According to the collision-ejection theory,when was the Moon formed?

At opposition,when Mars comes relatively close to Earth,where would it be seen in the sky by an observer in Earth's northern hemisphere?

The smallest planet in our solar system is:

The planet whose average density is less than that of water is:

Mercury is always much closer to the Sun than Venus is,and yet it never appears brighter than Venus,even at maximum brightness.Explain.

Mars has one hemisphere that is at a higher elevation than the other.In this way,it is similar to:

Which feature has NOT been seen or detected on Mars?

The length of a solar "day" (time between successive sunrises)on Venus is:

The mantle of Earth is composed of:

The Moon,because of the tides in Earth's oceans,is:

Mercury,unlike the Moon,has extensive plains between craters.The reason is thought to be that:

The lower atmosphere of Venus near the surface can be described as:

The interior of Mercury contains:

Auroras on Earth are caused by:

The long and high mountain ranges found in the centers of several major oceans on Earth,such as the Mid-Atlantic Ridge,are caused by:

The heat energy that powers tectonic activity on the surface of Earth originates deep in Earth's core.How does this energy move from the core to the surface?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

Characterizing Stars

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters