Question 1

Why was it difficult for astronomers to develop a clear understanding of the Milky Way until the last few decades?

Accepted Answer

Interstellar dust obscures most of the l...

Question 2

Almost all of the gas and dust in the Milky Way is located in the ____.

Accepted Answer

A)   halo
B)   central bulge
C)   disk
D)   corona
E)   centerF) B) and D)
G) A) and E)

Question 3

What parts of the galaxy are considered to make up the "spherical component"?

Accepted Answer

The central bulge and halo of ...

Question 4

The Sun orbits the center of the galaxy about once every ____.

Accepted Answer

A)   200,000 years
B)   2,000,000 years
C)   20,000,000 years
D)   200,000,000 years
E)   2,000,000,000 yearsF) All of the above
G) C) and D)

Question 5

The mass of the black hole in the center of the galaxy has been determined by observing the motion of stars orbiting it.

Accepted Answer

A) True 
 B)False

Question 6

A partial, or detached, segment of a spiral arm is referred to as a(n) " _______________."

Accepted Answer

The answer of A partial, or detached, segment of a...

Question 7

Population I stars are younger than Population II stars.

Accepted Answer

A) True 
 B)False

Question 8

The center of our galaxy contains a very intense source of radio and X-ray radiation named Sgr A*. What is it about this source that supports the idea that the radiation comes from a black hole?

Accepted Answer

A)   The radiation is strongly blueshifted, indicating that the object is collapsing.
B)   The radiation is strongly redshifted indicating that the object is growing.
C)   The radiation is coming from an incredibly small object.
D)   Radio waves can only be produced by matter orbiting a black hole.
E)   Only radiation from a black hole could penetrate the giant molecular clouds between Sgr A* and Earth.F) B) and E)
G) B) and C) C

Question 9

What is the correct ordering of galactic components using the new bottom-up hypothesis starting from oldest to youngest?

Accepted Answer

A)   galactic halo, average globular clusters, galactic disk
B)   galactic halo, galactic disk, average globular clusters
C)   average globular clusters, galactic halo, galactic disk
D)   average globular clusters, galactic disk, galactic halo
E)   galactic disk, average globular clusters, galactic halo.F) None of the above
G) C) and D)

Question 10

Explain how giant molecular clouds give rise to spiral tracers as they move through a disk with spiral density waves.

Accepted Answer

A spiral density wave is a stable concen...

Question 11

How have astronomers determined the mass of the Milky Way's supermassive black hole?

Accepted Answer

Stars near the galactic center...

Question 12

Galactic fountains are an important way to explain _____.

Accepted Answer

A)   the distribution of metals in and above the plane of the galactic disk
B)   the nature of dark matter
C)   the formation of the galactic disk from the first stages of our galaxy
D)   the generation and support of spiral density waves
E)   why the spiral arms are active sites of star formationF) B) and E)
G) C) and D) A

Question 13

The center of the galaxy has been studied extensively using visible light.

Accepted Answer

A) True 
 B)False

Question 14

The first astronomer to conclude that there is a relationship between period and luminosity of variable stars was _________.

Accepted Answer

A)   Henrietta Leavitt
B)   Caroline Herschel
C)   Harlow Shapley
D)   Albert Einstein
E)   Thomas WrightF) A) and C)
G) B) and E)

Question 15

The center of the Milky Way galaxy is in the direction of the constellation ____.

Accepted Answer

A)   Sagittarius
B)   Scorpius
C)   Orion
D)   Perseus
E)   AndromedaF) A) and B)
G) A) and C)

Question 16

At the center of our galaxy, ____.

Accepted Answer

A)   material is available to make stars but the region is too cold to support star formation
B)   large stars are formed by the collision of smaller stars
C)   stars form at the same rate as they do in the spiral arms
D)   there is no star formation since there is no gas present
E)   there is evidence of recent, rapid star formation and supernova explosionsF) A) and E)
G) B) and E)

Question 17

Discuss the evidence that supports the theory that there is a supermassive black hole at the center of our galaxy.

Accepted Answer

There is an intense source of radio ener...

Question 18

Why are Cepheid variables so important to the study of the Milky Way Galaxy?

Accepted Answer

Cepheid variables have a known relations...

Question 19

Elements above hydrogen and helium come from _____.

Accepted Answer

A)   the early stages of the Universe, before the formation of stars and galaxies
B)   the collision of neutron stars and black holes
C)   cooling and accretion of molecules in dense molecular clouds
D)   the last phases of stellar evolution and stellar "death"
E)   matter falling into supermassive black holesF) B) and C)
G) A) and B)

Question 20

The Sun orbits the center of our galaxy at a speed of about ________ km/s.

Accepted Answer

A)   100
B)   225
C)   500
D)   750
E)   1250F) A) and D)
G) A) and B) B

Exam 15: The Milky Way Galaxy

Why was it difficult for astronomers to develop a clear understanding of the Milky Way until the last few decades?

Correct AnswerverifiedInterstellar dust obscures most of the l...View AnswerShow Answer

Almost all of the gas and dust in the Milky Way is located in the ____.

Correct AnswerverifiedShow Answer

What parts of the galaxy are considered to make up the "spherical component"?

Correct AnswerverifiedThe central bulge and halo of ...View AnswerShow Answer

The Sun orbits the center of the galaxy about once every ____.

Correct AnswerverifiedShow Answer

The mass of the black hole in the center of the galaxy has been determined by observing the motion of stars orbiting it.

Correct AnswerverifiedShow Answer

A partial, or detached, segment of a spiral arm is referred to as a(n) " _______________."

Correct AnswerverifiedShow Answer

Population I stars are younger than Population II stars.

Correct AnswerverifiedShow Answer

The center of our galaxy contains a very intense source of radio and X-ray radiation named Sgr A*. What is it about this source that supports the idea that the radiation comes from a black hole?

Correct AnswerverifiedC

What is the correct ordering of galactic components using the new bottom-up hypothesis starting from oldest to youngest?

Correct AnswerverifiedShow Answer

Explain how giant molecular clouds give rise to spiral tracers as they move through a disk with spiral density waves.

Correct AnswerverifiedA spiral density wave is a stable concen...View AnswerShow Answer

How have astronomers determined the mass of the Milky Way's supermassive black hole?

Correct AnswerverifiedStars near the galactic center...View AnswerShow Answer

Galactic fountains are an important way to explain _____.

Correct AnswerverifiedA

The center of the galaxy has been studied extensively using visible light.

Correct AnswerverifiedShow Answer

The first astronomer to conclude that there is a relationship between period and luminosity of variable stars was _________.

Correct AnswerverifiedShow Answer

The center of the Milky Way galaxy is in the direction of the constellation ____.

Correct AnswerverifiedShow Answer

At the center of our galaxy, ____.

Correct AnswerverifiedShow Answer

Discuss the evidence that supports the theory that there is a supermassive black hole at the center of our galaxy.

Correct AnswerverifiedThere is an intense source of radio ener...View AnswerShow Answer

Why are Cepheid variables so important to the study of the Milky Way Galaxy?

Correct AnswerverifiedCepheid variables have a known relations...View AnswerShow Answer

Elements above hydrogen and helium come from _____.

Correct AnswerverifiedShow Answer

The Sun orbits the center of our galaxy at a speed of about ________ km/s.

Correct AnswerverifiedB

Correct Answer
verified
Interstellar dust obscures most of the l...
View Answer

Correct Answer
verified

Correct Answer
verified
The central bulge and halo of ...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
C

Correct Answer
verified

Correct Answer
verified
A spiral density wave is a stable concen...
View Answer

Correct Answer
verified
Stars near the galactic center...
View Answer

Correct Answer
verified
A

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
There is an intense source of radio ener...
View Answer

Correct Answer
verified
Cepheid variables have a known relations...
View Answer

Correct Answer
verified

Correct Answer
verified
B