Question 1

How do we know what goes on under the surface of the Sun?

Accepted Answer

A) We have X-ray images from satellites of the interior of the Sun. 
B) Astronomers create mathematical models that use the laws of physics,the Sun's observed composition and mass,and computers to predict internal conditions. 
C) We have sent probes below the surface of the Sun. 
D) By measuring Doppler shifts,we observe vibrations of the Sun's surface that are created deep within the Sun. 
E) both B and D 
A) We have X-ray images from satellites of the interior of the Sun. 
B) Astronomers create mathematical models that use the laws of physics,the Sun's observed composition and mass,and computers to predict internal conditions. 
C) We have sent probes below the surface of the Sun. 
D) By measuring Doppler shifts,we observe vibrations of the Sun's surface that are created deep within the Sun. 
E) both B and D

Question 2

Process of Science: Explain the reasoning that led to our understanding of nuclear energy being the source of the Sun's light.

Accepted Answer

The first step was measuring the distanc

Question 3

The Sun's average surface (photosphere)temperature is about

Accepted Answer

A) 1,000,000 K. 
B) 5,800 K. 
C) 1,000 K. 
D) 37,000 K. 
A) 1,000,000 K. 
B) 5,800 K. 
C) 1,000 K. 
D) 37,000 K.

Question 4

Which of the following choices is not a way by which we can study the inside of the Sun?

Accepted Answer

A) We can probe the interior of the Sun by studying the vibrations in its photosphere. 
B) We can make a computer model of the Sun's interior that allow us to predict the observable properties of the Sun. 
C) We can send a space probe into the Sun's photosphere. 
D) We can study solar neutrinos. 
A) We can probe the interior of the Sun by studying the vibrations in its photosphere. 
B) We can make a computer model of the Sun's interior that allow us to predict the observable properties of the Sun. 
C) We can send a space probe into the Sun's photosphere. 
D) We can study solar neutrinos.

Question 5

Which of the following best explains why the Sun's luminosity gradually rises over billions of years?

Accepted Answer

A) Fusion gradually decreases the number of independent particles in the core,allowing gravity to compress and heat the core,which in turn increases the fusion rate and the Sun's luminosity. 
B) Nuclear reactions in the Sun become more efficient with time,so that each fusion reaction releases more energy when the Sun is old than when it is young;this in turn raises the Sun's luminosity. 
C) The Sun's core gradually expands with time,and this expansion means there is more room for energy to be generated and hence increases the Sun's luminosity. 
D) The planets need more and more energy to maintain any life on them as time goes on,and therefore the Sun must bet hotter. 
A) Fusion gradually decreases the number of independent particles in the core,allowing gravity to compress and heat the core,which in turn increases the fusion rate and the Sun's luminosity. 
B) Nuclear reactions in the Sun become more efficient with time,so that each fusion reaction releases more energy when the Sun is old than when it is young;this in turn raises the Sun's luminosity. 
C) The Sun's core gradually expands with time,and this expansion means there is more room for energy to be generated and hence increases the Sun's luminosity. 
D) The planets need more and more energy to maintain any life on them as time goes on,and therefore the Sun must bet hotter.

Question 6

Which statement best describes what was called the solar neutrino problem?

Accepted Answer

A) Early experiments designed to detect solar neutrinos found them,but in fewer numbers than had been expected. 
B) It referred to the fact that neutrinos are extremely difficult to detect. 
C) Our understanding of fusion in the Sun suggested that neutrinos should be destroyed before they arrive at Earth,yet neutrinos were being detected. 
D) No one understood how it could be possible for neutrinos to be produced in the Sun. 
A) Early experiments designed to detect solar neutrinos found them,but in fewer numbers than had been expected. 
B) It referred to the fact that neutrinos are extremely difficult to detect. 
C) Our understanding of fusion in the Sun suggested that neutrinos should be destroyed before they arrive at Earth,yet neutrinos were being detected. 
D) No one understood how it could be possible for neutrinos to be produced in the Sun.

Question 7

The source of energy that keeps the Sun shining today is

Accepted Answer

A) nuclear fission. 
B) gravitational contraction. 
C) chemical reactions. 
D) nuclear fusion. 
A) nuclear fission. 
B) gravitational contraction. 
C) chemical reactions. 
D) nuclear fusion.

Question 8

Imagine you are plunging into the Sun,starting from Earth.Briefly describe what you will see as you descend.

Accepted Answer

First you will feel the light pressure o

Question 9

The Sun is a relatively young star,near the beginning of its life.

Accepted Answer

A) True 
 B)False

Question 10

Which is the strongest of the fundamental forces in the universe?

Accepted Answer

A) strong force 
B) weak force 
C) electromagnetic force 
D) gravitational force 
E) none of the above 
A) strong force 
B) weak force 
C) electromagnetic force 
D) gravitational force 
E) none of the above

Question 11

Suppose you put two protons near each other.Because of the electromagnetic force,the two protons will

Accepted Answer

A) collide. 
B) remain stationary. 
C) attract each other. 
D) repel each other. 
E) join together to form a nucleus. 
A) collide. 
B) remain stationary. 
C) attract each other. 
D) repel each other. 
E) join together to form a nucleus.

Question 12

How does the Sun generate energy today?

Accepted Answer

A) nuclear fission 
B) nuclear fusion 
C) chemical reactions 
D) gravitational contraction 
E) gradually expanding in size 
A) nuclear fission 
B) nuclear fusion 
C) chemical reactions 
D) gravitational contraction 
E) gradually expanding in size

Question 13

What is the average temperature of the surface of the Sun?

Accepted Answer

A) 1 million K 
B) 100,000 K 
C) 10,000 K 
D) 6,000 K 
E) 1,000 K 
A) 1 million K 
B) 100,000 K 
C) 10,000 K 
D) 6,000 K 
E) 1,000 K

Question 14

From the center outward,which of the following lists the "layers" of the Sun in the correct order?

Accepted Answer

A) core,radiation zone,convection zone,corona,chromosphere,photosphere 
B) core,corona,radiation zone,convection zone,photosphere,chromosphere 
C) core,radiation zone,convection zone,photosphere,chromosphere,corona 
D) core,convection zone,radiation zone,corona,chromosphere,photosphere 
E) core,convection zone,radiation zone,photosphere,chromosphere,corona 
A) core,radiation zone,convection zone,corona,chromosphere,photosphere 
B) core,corona,radiation zone,convection zone,photosphere,chromosphere 
C) core,radiation zone,convection zone,photosphere,chromosphere,corona 
D) core,convection zone,radiation zone,corona,chromosphere,photosphere 
E) core,convection zone,radiation zone,photosphere,chromosphere,corona

Question 15

The light radiated from the Sun's surface reaches Earth in about 8 minutes,but the energy of that light was released by fusion in the solar core about

Accepted Answer

A) three days ago. 
B) one hundred years ago. 
C) one thousand years ago. 
D) a few hundred thousand years ago. 
A) three days ago. 
B) one hundred years ago. 
C) one thousand years ago. 
D) a few hundred thousand years ago.

Question 16

What is granulation in the Sun?

Accepted Answer

A) the bubbling pattern on the photosphere produced by the underlying convection 
B) another name for the way sunspots look on the surface of the Sun 
C) elements in the Sun other than hydrogen and helium 
D) dust particles in the Sun that haven't been turned into plasma 
E) lumps of denser material in the Sun 
A) the bubbling pattern on the photosphere produced by the underlying convection 
B) another name for the way sunspots look on the surface of the Sun 
C) elements in the Sun other than hydrogen and helium 
D) dust particles in the Sun that haven't been turned into plasma 
E) lumps of denser material in the Sun

Question 17

How can we measure the strength of magnetic fields on the Sun?

Accepted Answer

A) by looking for the splitting of spectral lines in the Sun's spectrum 
B) by observing the sizes of sunspots: Bigger sunspots mean a stronger field 
C) by observing auroras here on Earth 
D) only by using sophisticated computer models,because there are no observational ways of measuring magnetic field strength 
A) by looking for the splitting of spectral lines in the Sun's spectrum 
B) by observing the sizes of sunspots: Bigger sunspots mean a stronger field 
C) by observing auroras here on Earth 
D) only by using sophisticated computer models,because there are no observational ways of measuring magnetic field strength

Question 18

If the Sun's core suddenly shrank a little bit,what would happen in the Sun?

Accepted Answer

A) The core would cool off and continue to shrink as its density increased. 
B) The density of the core would decrease,causing the core to cool off and expand. 
C) The core would heat up,causing it to radiate so much energy that it would shrink even more. 
D) The core would heat up,fusion rates would increase,and the core would re-expand. 
A) The core would cool off and continue to shrink as its density increased. 
B) The density of the core would decrease,causing the core to cool off and expand. 
C) The core would heat up,causing it to radiate so much energy that it would shrink even more. 
D) The core would heat up,fusion rates would increase,and the core would re-expand.

Question 19

Why do sunspots appear dark in pictures of the Sun?

Accepted Answer

A) They are too cold to emit any visible light. 
B) They actually are fairly bright but appear dark against the even brighter background of the surrounding Sun. 
C) They are holes in the solar surface through which we can see to deeper,darker layers of the Sun. 
D) They are tiny black holes,absorbing all light that hits them. 
E) They emit light in other wavelengths that we can't see. 
A) They are too cold to emit any visible light. 
B) They actually are fairly bright but appear dark against the even brighter background of the surrounding Sun. 
C) They are holes in the solar surface through which we can see to deeper,darker layers of the Sun. 
D) They are tiny black holes,absorbing all light that hits them. 
E) They emit light in other wavelengths that we can't see.

Question 20

Based on its surface temperature of 5,800 K,what color are most of the photons that leave the Sun's surface?

Accepted Answer

A) blue 
B) red 
C) yellow 
D) orange 
E) green 
A) blue 
B) red 
C) yellow 
D) orange 
E) green

Exam 14: Our Star

How do we know what goes on under the surface of the Sun?

Process of Science: Explain the reasoning that led to our understanding of nuclear energy being the source of the Sun's light.

The Sun's average surface (photosphere)temperature is about

Which of the following choices is not a way by which we can study the inside of the Sun?

Which of the following best explains why the Sun's luminosity gradually rises over billions of years?

Which statement best describes what was called the solar neutrino problem?

The source of energy that keeps the Sun shining today is

Imagine you are plunging into the Sun,starting from Earth.Briefly describe what you will see as you descend.

The Sun is a relatively young star,near the beginning of its life.

Which is the strongest of the fundamental forces in the universe?

Suppose you put two protons near each other.Because of the electromagnetic force,the two protons will

How does the Sun generate energy today?

What is the average temperature of the surface of the Sun?

From the center outward,which of the following lists the "layers" of the Sun in the correct order?

The light radiated from the Sun's surface reaches Earth in about 8 minutes,but the energy of that light was released by fusion in the solar core about

What is granulation in the Sun?

How can we measure the strength of magnetic fields on the Sun?

If the Sun's core suddenly shrank a little bit,what would happen in the Sun?

Why do sunspots appear dark in pictures of the Sun?

Based on its surface temperature of 5,800 K,what color are most of the photons that leave the Sun's surface?

A Modern View of the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light and Matter: Reading Messages from the Cosmos

Telescopes: Portals of Discovery

Our Planetary System

Formation of the Solar System

Planetary Geology: Earth and the Other Terrestrial Worlds

Planetary Atmospheres: Earth and the Other Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Other Planetary Systems: The New Science of Distant Worlds

Surveying the Stars

Star Birth

Star Stuff

The Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundations of Modern Cosmology

Galaxy Evolution

The Birth of the Universe

Dark Matter, Dark Energy, and the Fate of the Universe

Life in the Universe

Celestial Timekeeping and Navigation

Space and Time

Spacetime and Gravity

Building Blocks of the Universe

Filters