Question 1

A red supergiant is observed in a globular cluster in another galaxy (located 150,000 light years away) .It is predicted,based on its mass and age of the star that it will supernova in about 10,000 years.When will this supernova be visible on Earth?

Accepted Answer

A)   10,000 years from now
B)   10,000 years ago
C)   150,000 years from now
D)   150,000 years ago
E)   160,000 years from nowF) A) and C)
G) A) and E)

Question 2

The ________ phenomenon is an extremely energetic event which apparently occurs in the nuclei of massive galaxies during an early stage of their evolution.

Accepted Answer

The answer of The ________ phenomenon is an extremely energetic...

Question 3

From studies of the masses of individual galaxies and the masses of clusters of galaxies,it is now apparent that up to ________ of the universe is composed of dark matter.

Accepted Answer

The answer of From studies of the masses of individual...

Question 4

What is the Great Wall?

Accepted Answer

A)   It is a ridge on the Moon near the crater Birt.
B)   It is the distance beyond which astronomers cannot view any more galaxies or even quasars.
C)   It is a large sheet of galaxies measuring 70 Mpc by 200 Mpc.
D)   It is the time before the universe started expanding, about which we can never know anything.
E)   It is an enormous intergalactic cloud of dust and gas that hides more distant galaxies.F) B) and D)
G) B) and E)

Question 5

Infall of ________ may explain the higher than expected star formation rates in galaxies.

Accepted Answer

The answer of Infall of ________ may explain the higher...

Question 6

While our Milky Way's black hole is not massive enough to have once been quasar,it must have passed through its Seyfert phase by 3.5 billion years ago.Explain how we know this.

Accepted Answer

We are here.Life on Earth would have bee...

Question 7

For nearby spirals,their rotation curves help measure both light and dark matter.

Accepted Answer

A) True 
 B)False

Question 8

While we know of thousands of quasars,it is likely none of them still exist today.Explain.

Accepted Answer

Quasars are associated with the gravitat...

Question 9

How massive are the largest known galaxies?

Accepted Answer

A)   a few million solar masses
B)   a hundred million solar masses
C)   a few billion solar masses
D)   a trillion solar masses
E)   hundreds of trillions of solar massesF) B) and C)
G) All of the above

Question 10

The peak of the quasar epoch was:

Accepted Answer

A)   when there was still enough dark matter to fuel the supermassive black holes in their bar.
B)   when there was still sufficient mass to fuel the supermassive black holes at their center.
C)   before the formation of galaxies.
D)   before the star formation epoch.
E)   before mass had a chance to accumulate at the nucleus.F) All of the above
G) C) and D)

Question 11

Giant elliptical galaxies may be the result of ________ in the centers of rich clusters.

Accepted Answer

galaxy mer...

Question 12

Voids contain about what percentage of the universe's mass?

Accepted Answer

A)   0
B)   5-10
C)   40-50
D)   100
E)   cannot be determinedF) A) and C)
G) None of the above

Question 13

A galaxy is at a distance of one billion light years.Which of the following is true?

Accepted Answer

A)   We see the galaxy the way it will be in one billion years.
B)   We see the galaxy the way it was one billion years ago.
C)   We see the galaxy the way it was when the universe was one billion years old.
D)   We see what our galaxy will be like in one billion years.
E)   We have no knowledge of anything at that distance.F) B) and C)
G) A) and E)

Question 14

The energy radiated from a typical quasar requires that its black hole accrete about:

Accepted Answer

A)   1 solar mass per 100 years.
B)   1 solar mass per 10,000 years.
C)   1 Jupiter mass per year.
D)   10 solar masses per year.
E)   1,000 solar masses per year.F) B) and E)
G) A) and B)

Question 15

Rotation curves for spiral galaxies show:

Accepted Answer

A)   they are slowing down.
B)   rotation speed drops off further from the nucleus.
C)   most have dark halos.
D)   most of the mass lies in the nucleus.
E)   no relation to mass.F) A) and E)
G) A) and C)

Question 16

Spiral galaxies are much more common in the centers of rich clusters than in the universe as a whole.

Accepted Answer

A) True 
 B)False

Question 17

Describe how gravitational lensing works.What can it tell us about a quasar? What can it tell us about the galaxy that is doing the lensing? How is lensing valuable to the study of dark matter?

Accepted Answer

Gravitational lensing occurs when a near...

Question 18

What is a galaxy's rotation curve? To which galaxies is it best applied,and what does it tell us about the distribution of dark matter?

Accepted Answer

The speed of rotation at various distanc...

Question 19

A radio galaxy whose lobes are swept back as if forming a tail.This probably indicates that:

Accepted Answer

A)   this is evidence for intergalactic matter.
B)   the galaxy is about to evolve into a spiral.
C)   the galaxy is isolated, not part of a cluster.
D)   the galaxy is moving towards Earth.
E)   there must be another galaxy nearby.F) None of the above
G) A) and C)

Question 20

The type of radio galaxy that reveals its motion through the intergalactic medium is called a:

Accepted Answer

A)   quasar.
B)   dual lobe.
C)   bi-polar jet.
D)   head-tail.
E)   Seyfert.F) D) and E)
G) A) and E)

Exam 25: Galaxies and Dark Matter: The Large-Scale Structure of the Cosmos

The type of radio galaxy that reveals its motion through the intergalactic medium is called a:

Correct AnswerverifiedShow Answer

What is the Great Wall?

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The ________ phenomenon is an extremely energetic event which apparently occurs in the nuclei of massive galaxies during an early stage of their evolution.

Correct AnswerverifiedShow Answer

Voids contain about what percentage of the universe's mass?

Correct AnswerverifiedShow Answer

A radio galaxy whose lobes are swept back as if forming a tail.This probably indicates that:

Correct AnswerverifiedShow Answer

Infall of ________ may explain the higher than expected star formation rates in galaxies.

Correct AnswerverifiedShow Answer

From studies of the masses of individual galaxies and the masses of clusters of galaxies,it is now apparent that up to ________ of the universe is composed of dark matter.

Correct AnswerverifiedShow Answer

What is a galaxy's rotation curve? To which galaxies is it best applied,and what does it tell us about the distribution of dark matter?

Correct AnswerverifiedThe speed of rotation at various distanc...View AnswerShow Answer

A galaxy is at a distance of one billion light years.Which of the following is true?

Correct AnswerverifiedShow Answer

While our Milky Way's black hole is not massive enough to have once been quasar,it must have passed through its Seyfert phase by 3.5 billion years ago.Explain how we know this.

Correct AnswerverifiedWe are here.Life on Earth would have bee...View AnswerShow Answer

Spiral galaxies are much more common in the centers of rich clusters than in the universe as a whole.

Correct AnswerverifiedShow Answer

Giant elliptical galaxies may be the result of ________ in the centers of rich clusters.

Correct Answerverifiedgalaxy mer...View AnswerShow Answer

A red supergiant is observed in a globular cluster in another galaxy (located 150,000 light years away) .It is predicted,based on its mass and age of the star that it will supernova in about 10,000 years.When will this supernova be visible on Earth?

Correct AnswerverifiedShow Answer

The energy radiated from a typical quasar requires that its black hole accrete about:

Correct AnswerverifiedShow Answer

While we know of thousands of quasars,it is likely none of them still exist today.Explain.

Correct AnswerverifiedQuasars are associated with the gravitat...View AnswerShow Answer

Rotation curves for spiral galaxies show:

Correct AnswerverifiedShow Answer

Describe how gravitational lensing works.What can it tell us about a quasar? What can it tell us about the galaxy that is doing the lensing? How is lensing valuable to the study of dark matter?

Correct AnswerverifiedGravitational lensing occurs when a near...View AnswerShow Answer

The peak of the quasar epoch was:

Correct AnswerverifiedShow Answer

For nearby spirals,their rotation curves help measure both light and dark matter.

Correct AnswerverifiedShow Answer

How massive are the largest known galaxies?

Correct AnswerverifiedShow Answer

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The speed of rotation at various distanc...
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We are here.Life on Earth would have bee...
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galaxy mer...
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Quasars are associated with the gravitat...
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Gravitational lensing occurs when a near...
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