Question 1

Nuclear fusion in stars is controlled by the dependence of density on mass.

Accepted Answer

A) True 
 B)False

Question 2

Why is there a lower end to the main sequence? Why is there an upper end to the main sequence?

Accepted Answer

The main sequence is a continuous and di

Question 3

What force(s) are responsible for the collapse of an interstellar cloud?

Accepted Answer

A)  nuclear 
B)  gravity 
C)  electric 
D)  magnetic 
E)  both c and d 
A)  nuclear 
B)  gravity 
C)  electric 
D)  magnetic 
E)  both c and d

Question 4

____ are small luminous nebulae excited by nearby young stars.

Accepted Answer

A)  T Tauri stars 
B)  Herbig-Haro objects 
C)  O associations 
D)  Bok Globule 
E)  Giant molecular clouds 
A)  T Tauri stars 
B)  Herbig-Haro objects 
C)  O associations 
D)  Bok Globule 
E)  Giant molecular clouds

Question 5

Hydrostatic equilibrium refers to the balance between weight and pressure.

Accepted Answer

A) True 
 B)False

Question 6

Most stars generate their energy by the thermonuclear fusion of ____________________ to form ____________________.

Accepted Answer

The answer of Most stars generate their energy by the...

Question 7

Absorption lines due to interstellar gas

Accepted Answer

A)  are wider than the lines from stars because the gas is hotter than most stars. 
B)  are more narrow than the lines from stars because the gas has a lower pressure than stars. 
C)  indicate that the interstellar medium contains dust. 
D)  indicate that the interstellar medium is expanding away from the sun. 
E)  none of the above. 
A)  are wider than the lines from stars because the gas is hotter than most stars. 
B)  are more narrow than the lines from stars because the gas has a lower pressure than stars. 
C)  indicate that the interstellar medium contains dust. 
D)  indicate that the interstellar medium is expanding away from the sun. 
E)  none of the above.

Question 8

Stars are born in

Accepted Answer

A)  reflection nebulae. 
B)  dense molecular clouds. 
C)  HII regions. 
D)  the intercloud medium. 
E)  the local bubble. 
A)  reflection nebulae. 
B)  dense molecular clouds. 
C)  HII regions. 
D)  the intercloud medium. 
E)  the local bubble.

Question 9

____ occurs when most of the material collapsing to form a protostar has fallen into a disk around the star and a strong wind from the warm protostar ejects material from its poles.

Accepted Answer

A)  An emission nebula 
B)  Hydrostatic equilibrium 
C)  The proton-proton chain 
D)  The thermonuclear fusion of hydrogen 
E)  A bipolar outflow 
A)  An emission nebula 
B)  Hydrostatic equilibrium 
C)  The proton-proton chain 
D)  The thermonuclear fusion of hydrogen 
E)  A bipolar outflow

Question 10

Energy flows by radiation or convection inside stars but almost never by conduction.

Accepted Answer

A) True 
 B)False

Question 11

Ionization from the ____ in the Orion Nebula makes it glow.

Accepted Answer

A)  planets 
B)  coolest stars 
C)  hottest stars 
A)  planets 
B)  coolest stars 
C)  hottest stars

Nuclear fusion in stars is controlled by the dependence of density on mass.

Why is there a lower end to the main sequence? Why is there an upper end to the main sequence?

What force(s) are responsible for the collapse of an interstellar cloud?

____ are small luminous nebulae excited by nearby young stars.

Hydrostatic equilibrium refers to the balance between weight and pressure.

Most stars generate their energy by the thermonuclear fusion of to form .

Absorption lines due to interstellar gas

Stars are born in

____ occurs when most of the material collapsing to form a protostar has fallen into a disk around the star and a strong wind from the warm protostar ejects material from its poles.

Energy flows by radiation or convection inside stars but almost never by conduction.

Ionization from the ____ in the Orion Nebula makes it glow.

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Exam 9: The Formation and Structure of Stars

Nuclear fusion in stars is controlled by the dependence of density on mass.

Why is there a lower end to the main sequence? Why is there an upper end to the main sequence?

What force(s) are responsible for the collapse of an interstellar cloud?

____ are small luminous nebulae excited by nearby young stars.

Hydrostatic equilibrium refers to the balance between weight and pressure.

Most stars generate their energy by the thermonuclear fusion of ____________________ to form ____________________.

Absorption lines due to interstellar gas

Stars are born in

____ occurs when most of the material collapsing to form a protostar has fallen into a disk around the star and a strong wind from the warm protostar ejects material from its poles.

Energy flows by radiation or convection inside stars but almost never by conduction.

Ionization from the ____ in the Orion Nebula makes it glow.

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Most stars generate their energy by the thermonuclear fusion of to form .