Question 1

Globular clusters contain mostly blue stars.

Accepted Answer

A) True 
 B)False

Question 2

Of all forms of electromagnetic energy, radiation gives us the least access to our entire Milky Way Galaxy.

Accepted Answer

A)   visible light
B)   infrared
C)   X- ray
D)   ultraviolet
E)   radioF) C) and D)
G) A) and E)

Question 3

Molecules are found only in the clouds of the interstellar medium.

Accepted Answer

darkest an...

Question 4

Name four ways that the interstellar medium reveals its presence.

Accepted Answer

Hot gas glows as emission nebulae. Cool ...

Question 5

Neutral hydrogen can be detected because its electron occasionally its spin and creates the 21- cm emission line for radio observers.

Accepted Answer

flips or s...

Question 6

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

Accepted Answer

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

Question 7

The single most important determinant of the temperature, density, radius, luminosity, and pace of evolution of a protostar is its

Accepted Answer

A)   chemical composition.
B)   mass.
C)   magnetic field.
D)   spin.
E)   molecular composition.F) A) and E)
G) A) and D)

Question 8

Molecular clouds are much warmer than typical interstellar gas clouds.

Accepted Answer

A) True 
 B)False

Question 9

Relate bipolar jets to the T- Tauri phase and Herbig- Haro objects.

Accepted Answer

As the protostar condenses and spins in ...

Question 10

While many elemental spectral lines are visible, almost all molecular lines lie in the portion of the spectrum, since they are at much lower energy.

Accepted Answer

A)   visible light
B)   X- ray
C)   ultraviolet
D)   infrared
E)   radioF) All of the above
G) A) and B)

Question 11

Interstellar gas is composed mainly of

Accepted Answer

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

Question 12

Which of these is NOT a consequence of dust in the interstellar medium?

Accepted Answer

A)   red light from the emission nebulae
B)   reddening of stars' light that passes through the dust
C)   the dark nebulae that block 90% of the Milky Way from us visually
D)   blue reflection nebulae around the Pleiades
E)   terrestrial planets like our ownF) B) and C)
G) C) and D)

Question 13

The 21- cm line of hydrogen is strongly absorbed by interstellar dust.

Accepted Answer

A) True 
 B)False

Question 14

Stars evolve along the main sequence.

Accepted Answer

A) True 
 B)False

Question 15

Contrast the brightest stars of young open and old globular clusters.

Accepted Answer

Hot, blue, main- sequence stars light up...

Question 16

Interstellar matter is distributed very evenly throughout the galaxy.

Accepted Answer

A) True 
 B)False

Question 17

If the dark nebula are really dark, how do we know they are there?

Accepted Answer

In some cases, they are not thick enough...

Question 18

A fragment of a collapsing gas cloud that comes to equilibrium with a central temperature of 4 million K will become a

Accepted Answer

A)   T- Tauri star.
B)   stage 1 protostar.
C)   black hole.
D)   brown dwarf.
E)   black dwarf.F) B) and C)
G) B) and D)

Question 19

In general, Globular clusters are and than open clusters.

Accepted Answer

older, redder, or bi...

Question 20

Red sunset, red lunar eclipses, blue skies, and reflection nebulae are all the result of the
of visible light off tiny dust particles.

Accepted Answer

The answer of Red sunset, red lunar eclipses, blue skies,...

Exam 12: The Interstellar Medium: Star Formation in the Milky Way

Stars evolve along the main sequence.

Correct AnswerverifiedShow Answer

A fragment of a collapsing gas cloud that comes to equilibrium with a central temperature of 4 million K will become a

Correct AnswerverifiedShow Answer

Red sunset, red lunar eclipses, blue skies, and reflection nebulae are all the result of the of visible light off tiny dust particles.

Correct AnswerverifiedShow Answer

Name four ways that the interstellar medium reveals its presence.

Correct AnswerverifiedHot gas glows as emission nebulae. Cool ...View AnswerShow Answer

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

Correct AnswerverifiedShow Answer

Contrast the brightest stars of young open and old globular clusters.

Correct AnswerverifiedHot, blue, main- sequence stars light up...View AnswerShow Answer

In general, Globular clusters are and than open clusters.

Correct Answerverifiedolder, redder, or bi...View AnswerShow Answer

Molecules are found only in the clouds of the interstellar medium.

Correct Answerverifieddarkest an...View AnswerShow Answer

Neutral hydrogen can be detected because its electron occasionally its spin and creates the 21- cm emission line for radio observers.

Correct Answerverifiedflips or s...View AnswerShow Answer

The 21- cm line of hydrogen is strongly absorbed by interstellar dust.

Correct AnswerverifiedShow Answer

Molecular clouds are much warmer than typical interstellar gas clouds.

Correct AnswerverifiedShow Answer

The single most important determinant of the temperature, density, radius, luminosity, and pace of evolution of a protostar is its

Correct AnswerverifiedShow Answer

Relate bipolar jets to the T- Tauri phase and Herbig- Haro objects.

Correct AnswerverifiedAs the protostar condenses and spins in ...View AnswerShow Answer

Interstellar gas is composed mainly of

Correct AnswerverifiedShow Answer

Of all forms of electromagnetic energy, radiation gives us the least access to our entire Milky Way Galaxy.

Correct AnswerverifiedShow Answer

Which of these is NOT a consequence of dust in the interstellar medium?

Correct AnswerverifiedShow Answer

Interstellar matter is distributed very evenly throughout the galaxy.

Correct AnswerverifiedShow Answer

While many elemental spectral lines are visible, almost all molecular lines lie in the portion of the spectrum, since they are at much lower energy.

Correct AnswerverifiedShow Answer

If the dark nebula are really dark, how do we know they are there?

Correct AnswerverifiedIn some cases, they are not thick enough...View AnswerShow Answer

Globular clusters contain mostly blue stars.

Correct AnswerverifiedShow Answer

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Hot gas glows as emission nebulae. Cool ...
View Answer

Correct Answer
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Correct Answer
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Hot, blue, main- sequence stars light up...
View Answer

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older, redder, or bi...
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Correct Answer
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darkest an...
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flips or s...
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As the protostar condenses and spins in ...
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Correct Answer
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In some cases, they are not thick enough...
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Correct Answer
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