Question 1

The best wavelength to use to observe a solar prominence is:

Accepted Answer

A)  550 nm, green visible light 
B)  656 nm, a red hydrogen emission line 
C)  16 mm, an ultraviolet emission line 
D)  21 cm, microwave emission 
E)  0.02 nm, X-ray emission 
A)  550 nm, green visible light 
B)  656 nm, a red hydrogen emission line 
C)  16 mm, an ultraviolet emission line 
D)  21 cm, microwave emission 
E)  0.02 nm, X-ray emission

Question 2

If the Sun stopped nuclear fusion in its core, it would take 1,000 years for its luminosity to change.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following curves best matches the shape of a graph of the density of material inside the Sun (in thousands of kg/m3) as you move further away from the center?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 4

If a sunspot appears one-quarter as bright as the surrounding photosphere, and the average temperature of the photosphere is 5800 K, what is the temperature of the gas in this sunspot?

Accepted Answer

A)  3625 K 
B)  4100 K 
C)  4500 K 
D)  5200 K 
E)  5500 K 
A)  3625 K 
B)  4100 K 
C)  4500 K 
D)  5200 K 
E)  5500 K

Question 5

List three methods of energy transport in nature and explain how the energy is being transferred in each of those methods. Which two are means by which energy is transported inside the Sun?

Accepted Answer

Radiative-via electromagnetic radiation;

Question 6

The solar neutrino problem was solved by:

Accepted Answer

A)  adjusting the rate of hydrogen burning in solar models 
B)  improving detector efficiencies so more neutrinos were observed 
C)  postulating that neutrinos had mass and oscillated between three different types 
D)  lowering the percentage of helium in models of solar composition 
E)  correctly measuring the density of the Sun's interior 
A)  adjusting the rate of hydrogen burning in solar models 
B)  improving detector efficiencies so more neutrinos were observed 
C)  postulating that neutrinos had mass and oscillated between three different types 
D)  lowering the percentage of helium in models of solar composition 
E)  correctly measuring the density of the Sun's interior

Question 7

What is "limb darkening"? Explain why limb darkening occurs in the Sun.

Accepted Answer

Limb darkening means that the edges of t

Question 8

Which of the following method(s) is (are) NOT used to transport energy from the core of the Sun to its surface?

Accepted Answer

A)  radiation 
B)  convection 
C)  conduction 
D)  All of the above are important in the solar interior. 
E)  None of the above are important in the solar interior. 
A)  radiation 
B)  convection 
C)  conduction 
D)  All of the above are important in the solar interior. 
E)  None of the above are important in the solar interior.

Question 9

Light from the Sun's photosphere reaches Earth approximately _________ times faster than photons released in fusion in the core.

Accepted Answer

A)  1,000 
B)  600,000 
C)  1 million 
D)  6 billion 
E)  10 billion 
A)  1,000 
B)  600,000 
C)  1 million 
D)  6 billion 
E)  10 billion

Question 10

When you turn on the heater in a car, the passengers in the front seat warm up first, then eventually the warm air gets to the passengers in the back seat. This is an example of energy being transported by:

Accepted Answer

A)  radiation 
B)  convection 
C)  conduction 
D)  convection and conduction 
E)  radiation and conduction 
A)  radiation 
B)  convection 
C)  conduction 
D)  convection and conduction 
E)  radiation and conduction

Question 11

Which of the following is NOT a result of an increase in solar activity?

Accepted Answer

A)  The altitudes of orbiting satellites decrease. 
B)  Airplanes have trouble navigating. 
C)  Stronger auroras are seen. 
D)  Power grids can be damaged. 
E)  All of the above can be caused by increased solar activity. 
A)  The altitudes of orbiting satellites decrease. 
B)  Airplanes have trouble navigating. 
C)  Stronger auroras are seen. 
D)  Power grids can be damaged. 
E)  All of the above can be caused by increased solar activity.

Question 12

If coronal holes covered a larger fraction of the Sun's surface, the solar wind would contain a higher density of particles.

Accepted Answer

A) True 
 B)False

Question 13

Neutrinos are particles with small masses that interact easily with normal matter.

Accepted Answer

A) True 
 B)False

Question 14

What do astronomers mean when they say that the Sun makes energy by hydrogen burning?

Accepted Answer

A)  The Sun is combusting hydrogen in a fire and releasing energy. 
B)  The Sun is fusing hydrogen into uranium and releasing energy. 
C)  The Sun is made of mostly hydrogen at very high temperature. 
D)  The Sun is fusing hydrogen into helium and releasing energy. 
E)  The Sun is accumulating hydrogen from the solar wind and releasing energy. 
A)  The Sun is combusting hydrogen in a fire and releasing energy. 
B)  The Sun is fusing hydrogen into uranium and releasing energy. 
C)  The Sun is made of mostly hydrogen at very high temperature. 
D)  The Sun is fusing hydrogen into helium and releasing energy. 
E)  The Sun is accumulating hydrogen from the solar wind and releasing energy.

Question 15

Hydrostatic equilibrium is a balance between:

Accepted Answer

A)  heat and centrifugal force 
B)  core temperature and surface temperature 
C)  pressure and gravity 
D)  radiation and heat 
E)  centrifugal force and gravity 
A)  heat and centrifugal force 
B)  core temperature and surface temperature 
C)  pressure and gravity 
D)  radiation and heat 
E)  centrifugal force and gravity

Question 16

The image below shows the Sun during a solar eclipse at visible wavelengths.   Which part of the Sun is visible around the shadow of the Moon?

Accepted Answer

A)  chromosphere 
B)  photosphere 
C)  radiative zone 
D)  convective zone 
E)  corona 
A)  chromosphere 
B)  photosphere 
C)  radiative zone 
D)  convective zone 
E)  corona

Question 17

Explain what the heliosphere is and how it helps protect life on Earth.

Accepted Answer

The heliosphere is the area around the S

Question 18

We know the Sun's corona is very hot because:

Accepted Answer

A)  we observe it emitting radiation at visible wavelengths 
B)  the chromosphere and the photosphere are that hot, too 
C)  we observe absorption from highly ionized atoms of iron and calcium in its spectrum 
D)  the gas emits most of its radiation at radio wavelengths 
E)  all of the above 
A)  we observe it emitting radiation at visible wavelengths 
B)  the chromosphere and the photosphere are that hot, too 
C)  we observe absorption from highly ionized atoms of iron and calcium in its spectrum 
D)  the gas emits most of its radiation at radio wavelengths 
E)  all of the above

Question 19

The net result of the proton-proton chain of nuclear reactions is that four protons are converted into one helium nucleus and energy, electrons, and neutrinos are released.

Accepted Answer

A) True 
 B)False

Question 20

The surface of the Sun appears sharp when we look at it in visible light because:

Accepted Answer

A)  the photosphere is cooler than the layers below it 
B)  the photosphere is thin compared to the other layers in the Sun 
C)  the photosphere is much less dense than the convection zone 
D)  the photosphere is transparent to radiation 
E)  the Sun has a distinct surface 
A)  the photosphere is cooler than the layers below it 
B)  the photosphere is thin compared to the other layers in the Sun 
C)  the photosphere is much less dense than the convection zone 
D)  the photosphere is transparent to radiation 
E)  the Sun has a distinct surface

Exam 14: Our Starthe Sun

The best wavelength to use to observe a solar prominence is:

If the Sun stopped nuclear fusion in its core, it would take 1,000 years for its luminosity to change.

Which of the following curves best matches the shape of a graph of the density of material inside the Sun (in thousands of kg/m3) as you move further away from the center?

If a sunspot appears one-quarter as bright as the surrounding photosphere, and the average temperature of the photosphere is 5800 K, what is the temperature of the gas in this sunspot?

List three methods of energy transport in nature and explain how the energy is being transferred in each of those methods. Which two are means by which energy is transported inside the Sun?

The solar neutrino problem was solved by:

What is "limb darkening"? Explain why limb darkening occurs in the Sun.

Which of the following method(s) is (are) NOT used to transport energy from the core of the Sun to its surface?

Light from the Sun's photosphere reaches Earth approximately _________ times faster than photons released in fusion in the core.

When you turn on the heater in a car, the passengers in the front seat warm up first, then eventually the warm air gets to the passengers in the back seat. This is an example of energy being transported by:

Which of the following is NOT a result of an increase in solar activity?

If coronal holes covered a larger fraction of the Sun's surface, the solar wind would contain a higher density of particles.

Neutrinos are particles with small masses that interact easily with normal matter.

What do astronomers mean when they say that the Sun makes energy by hydrogen burning?

Hydrostatic equilibrium is a balance between:

The image below shows the Sun during a solar eclipse at visible wavelengths. Which part of the Sun is visible around the shadow of the Moon?

Explain what the heliosphere is and how it helps protect life on Earth.

We know the Sun's corona is very hot because:

The net result of the proton-proton chain of nuclear reactions is that four protons are converted into one helium nucleus and energy, electrons, and neutrinos are released.

The surface of the Sun appears sharp when we look at it in visible light because:

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornmentsmoons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters

Which of the following curves best matches the shape of a graph of the density of material inside the Sun (in thousands of kg/m³) as you move further away from the center?