Question 1

Which of the following is TRUE regarding planetary nebulae?

Accepted Answer

A)  Some are spherical, but most have bipolar structure. 
B)  They are the result of the mass loss during the main sequence stage of the most massive stars. 
C)  They are the rings of material surrounding newly formed stars that will eventually form the planetary systems. 
D)  They are the ejected envelopes of highly evolved brown dwarf stars. 
E)  They are the coronas surrounding most blue stragglers. 
A)  Some are spherical, but most have bipolar structure. 
B)  They are the result of the mass loss during the main sequence stage of the most massive stars. 
C)  They are the rings of material surrounding newly formed stars that will eventually form the planetary systems. 
D)  They are the ejected envelopes of highly evolved brown dwarf stars. 
E)  They are the coronas surrounding most blue stragglers. A

Question 2

Just as a low-mass main sequence star runs out of fuel in its core, it actually becomes brighter. How is this possible?

Accepted Answer

A)  Helium fusion gives more energy than hydrogen fusion does, based on masses. 
B)  Its outer envelope is stripped away and we see the brilliant core. 
C)  The core contracts, raising the temperature and increasing the size of the region of hydrogen shell-burning. 
D)  It explodes. 
E)  It immediately starts to fuse helium. 
A)  Helium fusion gives more energy than hydrogen fusion does, based on masses. 
B)  Its outer envelope is stripped away and we see the brilliant core. 
C)  The core contracts, raising the temperature and increasing the size of the region of hydrogen shell-burning. 
D)  It explodes. 
E)  It immediately starts to fuse helium. C

Question 3

Protostars can be observed in

Accepted Answer

A)  the Crab Nebula. 
B)  the Andromeda Galaxy. 
C)  the Orion Nebula. 
D)  our Solar System. 
E)  the Helix Nebula. 
A)  the Crab Nebula. 
B)  the Andromeda Galaxy. 
C)  the Orion Nebula. 
D)  our Solar System. 
E)  the Helix Nebula. C

Question 4

Modern astronomers have observed the complete life cycle for many stars, making stellar evolution one of the best-tested astronomical theories.

Accepted Answer

A) True 
 B)False

Question 5

Describe the helium flash and why it occurs.

Accepted Answer

When the core of a red giant has reached

Question 6

The Orion Nebula glows strongly in the infrared.

Accepted Answer

A) True 
 B)False

Question 7

Interstellar gas is composed of

Accepted Answer

A)  only hydrogen. 
B)  90% hydrogen, 9% helium by weight. 
C)  10% hydrogen, 90% helium by numbers of atoms. 
D)  some hydrogen, but mainly carbon dioxide. 
E)  ammonia, methane, and water vapor. 
A)  only hydrogen. 
B)  90% hydrogen, 9% helium by weight. 
C)  10% hydrogen, 90% helium by numbers of atoms. 
D)  some hydrogen, but mainly carbon dioxide. 
E)  ammonia, methane, and water vapor.

Question 8

The "helium flash" occurs at what stage in stellar evolution?

Accepted Answer

A)  When the T Tauri bipolar jets shoot out 
B)  In the middle of the main sequence stage 
C)  Red giant 
D)  Horizontal branch 
E)  Planetary nebula 
A)  When the T Tauri bipolar jets shoot out 
B)  In the middle of the main sequence stage 
C)  Red giant 
D)  Horizontal branch 
E)  Planetary nebula

Question 9

Which of the following best describes the evolutionary track followed on the H-R diagram for the most massive stars?

Accepted Answer

A)  Vertically upward, along the left edge of the diagram 
B)  Diagonally to lower right, then vertical, then horizontally left 
C)  Horizontally right, diagonally to lower left, then horizontally right 
D)  Horizontally right 
E)  Horizontally right, then forms a clockwise loop 
A)  Vertically upward, along the left edge of the diagram 
B)  Diagonally to lower right, then vertical, then horizontally left 
C)  Horizontally right, diagonally to lower left, then horizontally right 
D)  Horizontally right 
E)  Horizontally right, then forms a clockwise loop

Question 10

All globular clusters in our Milky Way are about how old?

Accepted Answer

A)  Less than a million years 
B)  Ten-fifty million years old 
C)  One to three billion years old 
D)  Around ten billion years old 
E)  A variety of ages, from newly born to twenty billion years old 
A)  Less than a million years 
B)  Ten-fifty million years old 
C)  One to three billion years old 
D)  Around ten billion years old 
E)  A variety of ages, from newly born to twenty billion years old

Question 11

Most stars in the Milky Way probably formed

Accepted Answer

A)  alone. 
B)  in intergalactic space, then were swept up into the Galaxy. 
C)  in clusters in the Galaxy's spiral arms. 
D)  from planetary nebulae. 
E)  in the galactic Nucleus, then migrated outward later. 
A)  alone. 
B)  in intergalactic space, then were swept up into the Galaxy. 
C)  in clusters in the Galaxy's spiral arms. 
D)  from planetary nebulae. 
E)  in the galactic Nucleus, then migrated outward later.

Question 12

Why does gravitational contraction halt in collapsing protostars?

Accepted Answer

Gravitational contraction heat

Question 13

Which type of star has the strongest stellar winds?

Accepted Answer

A)  Giant K- and M-type stars 
B)  White dwarfs 
C)  Dwarf K- and M-type stars 
D)  Main sequence O- and B-type stars 
E)  T Tauri stars 
A)  Giant K- and M-type stars 
B)  White dwarfs 
C)  Dwarf K- and M-type stars 
D)  Main sequence O- and B-type stars 
E)  T Tauri stars

Question 14

A typical protostar may be several thousand times more luminous than the Sun. What is the source of this energy?

Accepted Answer

A)  Chemical combustion of hydrocarbons 
B)  Nuclear fusion in its core 
C)  From the release of gravitational energy as the protostar continues to shrink 
D)  The ionization of the gas as it heats up 
E)  From nearby hot stars or supernovae that have initiated the star formation process 
A)  Chemical combustion of hydrocarbons 
B)  Nuclear fusion in its core 
C)  From the release of gravitational energy as the protostar continues to shrink 
D)  The ionization of the gas as it heats up 
E)  From nearby hot stars or supernovae that have initiated the star formation process

Question 15

What effect do even thin clouds of dust have on light passing through them?

Accepted Answer

A)  The light that passes though them is blue shifted due to the cloud's approach. 
B)  It dims the light of all more distant stars. 
C)  Even a little can completely block all light, such as the Horsehead Nebula. 
D)  Its motion causes the light of stars beyond to twinkle. 
E)  Its motion causes all light to be redshifted as it passes through these clouds. 
A)  The light that passes though them is blue shifted due to the cloud's approach. 
B)  It dims the light of all more distant stars. 
C)  Even a little can completely block all light, such as the Horsehead Nebula. 
D)  Its motion causes the light of stars beyond to twinkle. 
E)  Its motion causes all light to be redshifted as it passes through these clouds.

Question 16

A protostar develops a bipolar flow of gas when it is still surrounded by an equatorial disk of ________.

Accepted Answer

The answer of A protostar develops a bipolar flow of...

Question 17

The density of interstellar dust is very low, yet it still blocks starlight because

Accepted Answer

A)  it is so cold it absorbs higher energy photons. 
B)  there is 100 times more opaque gas than dust present in the ISM. 
C)  the dust particles are about the same size as the light waves they absorb. 
D)  the dust particles are irregular in shape. 
E)  ice particles reflect all light back toward their stars, not toward us. 
A)  it is so cold it absorbs higher energy photons. 
B)  there is 100 times more opaque gas than dust present in the ISM. 
C)  the dust particles are about the same size as the light waves they absorb. 
D)  the dust particles are irregular in shape. 
E)  ice particles reflect all light back toward their stars, not toward us.

Question 18

Most stars are usually formed singularly or as binaries, not in clusters.

Accepted Answer

A) True 
 B)False

Question 19

Some regions along the plane of the Milky Way appear dark because

Accepted Answer

A)  there are no stars in these areas. 
B)  stars in that region are hidden by interstellar gas. 
C)  stars in that region are hidden by dark dust particles. 
D)  many brown dwarfs in those areas absorb light which they turn into heat. 
E)  many black holes absorb all light from those directions. 
A)  there are no stars in these areas. 
B)  stars in that region are hidden by interstellar gas. 
C)  stars in that region are hidden by dark dust particles. 
D)  many brown dwarfs in those areas absorb light which they turn into heat. 
E)  many black holes absorb all light from those directions.

Question 20

The most important fact about a cluster of stars that makes them useful for studying star formation is that

Accepted Answer

A)  all the stars formed from the same cloud. 
B)  all the stars formed at about the same time. 
C)  all the stars are at the same distance from Earth. 
D)  all the stars have the same chemical composition. 
E)  all the stars are the same spectral type. 
A)  all the stars formed from the same cloud. 
B)  all the stars formed at about the same time. 
C)  all the stars are at the same distance from Earth. 
D)  all the stars have the same chemical composition. 
E)  all the stars are the same spectral type.

Which of the following is TRUE regarding planetary nebulae?

Just as a low-mass main sequence star runs out of fuel in its core, it actually becomes brighter. How is this possible?

Protostars can be observed in

Modern astronomers have observed the complete life cycle for many stars, making stellar evolution one of the best-tested astronomical theories.

Describe the helium flash and why it occurs.

The Orion Nebula glows strongly in the infrared.

Interstellar gas is composed of

The "helium flash" occurs at what stage in stellar evolution?

Which of the following best describes the evolutionary track followed on the H-R diagram for the most massive stars?

All globular clusters in our Milky Way are about how old?

Most stars in the Milky Way probably formed

Why does gravitational contraction halt in collapsing protostars?

Which type of star has the strongest stellar winds?

A typical protostar may be several thousand times more luminous than the Sun. What is the source of this energy?

What effect do even thin clouds of dust have on light passing through them?

A protostar develops a bipolar flow of gas when it is still surrounded by an equatorial disk of ________.

The density of interstellar dust is very low, yet it still blocks starlight because

Most stars are usually formed singularly or as binaries, not in clusters.

Some regions along the plane of the Milky Way appear dark because

The most important fact about a cluster of stars that makes them useful for studying star formation is that

The Night Sky

Light and Telescopes

The Solar System

Earth and Its Moon

The Eight Planets

Small Bodies in the Solar System

Formation of Planetary Systems

The Sun

Measuring the Stars

Stellar Explosions

Black Holes

The Milky Way Galaxy

Galaxies

Cosmology and the Universe

Filters

Exam 10: Star Formation and Evolution

Which of the following is TRUE regarding planetary nebulae?

Just as a low-mass main sequence star runs out of fuel in its core, it actually becomes brighter. How is this possible?

Protostars can be observed in

Modern astronomers have observed the complete life cycle for many stars, making stellar evolution one of the best-tested astronomical theories.

Describe the helium flash and why it occurs.

The Orion Nebula glows strongly in the infrared.

Interstellar gas is composed of

The "helium flash" occurs at what stage in stellar evolution?

Which of the following best describes the evolutionary track followed on the H-R diagram for the most massive stars?

All globular clusters in our Milky Way are about how old?

Most stars in the Milky Way probably formed

Why does gravitational contraction halt in collapsing protostars?

Which type of star has the strongest stellar winds?

A typical protostar may be several thousand times more luminous than the Sun. What is the source of this energy?

What effect do even thin clouds of dust have on light passing through them?

A protostar develops a bipolar flow of gas when it is still surrounded by an equatorial disk of ________.

The density of interstellar dust is very low, yet it still blocks starlight because

Most stars are usually formed singularly or as binaries, not in clusters.

Some regions along the plane of the Milky Way appear dark because

The most important fact about a cluster of stars that makes them useful for studying star formation is that

The Night Sky

Light and Telescopes

The Solar System

Earth and Its Moon

The Eight Planets

Small Bodies in the Solar System

Formation of Planetary Systems

The Sun

Measuring the Stars

Stellar Explosions

Black Holes

The Milky Way Galaxy

Galaxies

Cosmology and the Universe

Filters