Question 1

On the Hubble tuning-fork diagram shown in Figure 17-15 of the text, the irregular galaxies are placed between the tines at the right end of the diagram. Why is this?

Accepted Answer

A)  These are the least-massive galaxies, and on the diagram the masses increase from left to right. 
B)  These are the youngest galaxies, and on the diagram the ages increase from right to left. 
C)  These are the oldest galaxies, and on the diagram the ages increase from left to right. 
D)  The placement is somewhat arbitrary. 
A)  These are the least-massive galaxies, and on the diagram the masses increase from left to right. 
B)  These are the youngest galaxies, and on the diagram the ages increase from right to left. 
C)  These are the oldest galaxies, and on the diagram the ages increase from left to right. 
D)  The placement is somewhat arbitrary.

Question 2

The Hubble law states that

Accepted Answer

A)  all galaxies are being repelled from the central "engine" of the universe, with the ones closest to the center traveling fastest. 
B)  all galaxies are being pulled toward a central gravitational attractor in the universe, with the ones closest to the center traveling fastest. 
C)  the more distant a galaxy is from the Sun, the faster it is traveling toward the Sun. 
D)  the more distant a galaxy is from the Sun, the faster it is traveling away from the Sun. 
A)  all galaxies are being repelled from the central "engine" of the universe, with the ones closest to the center traveling fastest. 
B)  all galaxies are being pulled toward a central gravitational attractor in the universe, with the ones closest to the center traveling fastest. 
C)  the more distant a galaxy is from the Sun, the faster it is traveling toward the Sun. 
D)  the more distant a galaxy is from the Sun, the faster it is traveling away from the Sun.

Question 3

A supercluster of galaxies is a

Accepted Answer

A)  cluster of galaxy clusters. 
B)  cluster of galaxies that is packed much more densely than normal clusters, giving it a higher mass. 
C)  phrase describing all the galaxies in the universe as a single system. 
D)  cluster of galaxies that is spread out over a larger than normal volume of space. 
A)  cluster of galaxy clusters. 
B)  cluster of galaxies that is packed much more densely than normal clusters, giving it a higher mass. 
C)  phrase describing all the galaxies in the universe as a single system. 
D)  cluster of galaxies that is spread out over a larger than normal volume of space.

Question 4

The Hubble flow, demonstrating the expansion of the universe, occurs

Accepted Answer

A)  between galaxies in clusters, clusters in superclusters, and superclusters in wider regions of space. 
B)  only between superclusters of galaxies. 
C)  between stars in galaxies, galaxies in clusters, clusters in superclusters, and superclusters over wider regions of space. 
D)  between clusters of galaxies in superclusters and between superclusters over wider ranges of space. 
A)  between galaxies in clusters, clusters in superclusters, and superclusters in wider regions of space. 
B)  only between superclusters of galaxies. 
C)  between stars in galaxies, galaxies in clusters, clusters in superclusters, and superclusters over wider regions of space. 
D)  between clusters of galaxies in superclusters and between superclusters over wider ranges of space.

Question 5

The Tully-Fisher relationship can be used to measure the luminosity of (and thus the distance to)

Accepted Answer

A)  elliptical galaxies. 
B)  spiral galaxies. 
C)  globular clusters. 
D)  Type II supernovae. 
A)  elliptical galaxies. 
B)  spiral galaxies. 
C)  globular clusters. 
D)  Type II supernovae.

Question 6

What is the classification for a spiral galaxy with a large nuclear region and tightly wound arms?

Accepted Answer

A)  Sb 
B)  SBc 
C)  Sc 
D)  Sa 
A)  Sb 
B)  SBc 
C)  Sc 
D)  Sa

Question 7

In the verification of the Hubble law for the expansion of the universe and the determination of the constant H0, the greatest difficulty has been

Accepted Answer

A)  allowance for gravitational redshifting of light by high gravitational fields at distant galaxies. 
B)  accurate determination of distances to very distant galaxies. 
C)  measurement of recession velocities of distant galaxies by Doppler shift. 
D)  the identification of distant objects as galaxies, rather than very bright, nearby stars. 
A)  allowance for gravitational redshifting of light by high gravitational fields at distant galaxies. 
B)  accurate determination of distances to very distant galaxies. 
C)  measurement of recession velocities of distant galaxies by Doppler shift. 
D)  the identification of distant objects as galaxies, rather than very bright, nearby stars.

Question 8

Arrange these objects according to size, largest to smallest.

Accepted Answer

A)  globular clusters, traditional dwarf elliptical, ultra-compact dwarfs 
B)  globular clusters, ultra-compact dwarfs, traditional dwarf elliptical 
C)  traditional dwarf elliptical, ultra-compact dwarfs, globular clusters 
D)  ultra-compact dwarfs, traditional dwarf galaxies, globular clusters 
A)  globular clusters, traditional dwarf elliptical, ultra-compact dwarfs 
B)  globular clusters, ultra-compact dwarfs, traditional dwarf elliptical 
C)  traditional dwarf elliptical, ultra-compact dwarfs, globular clusters 
D)  ultra-compact dwarfs, traditional dwarf galaxies, globular clusters

Question 9

The Milky Way Galaxy is a(n)

Accepted Answer

A)  member of a poor cluster of galaxies. 
B)  member of a rich, irregular cluster of thousands of galaxies. 
C)  isolated galaxy, not a member of any cluster. 
D)  member of a rich, regular cluster of thousands of galaxies. 
A)  member of a poor cluster of galaxies. 
B)  member of a rich, irregular cluster of thousands of galaxies. 
C)  isolated galaxy, not a member of any cluster. 
D)  member of a rich, regular cluster of thousands of galaxies.

Question 10

Grand-design spiral galaxies

Accepted Answer

A)  have a central bulge that does not rotate. 
B)  are encompassed within a large lens-shaped disk of dark matter. 
C)  are orbited by globular clusters that also exhibit star formation. 
D)  are most often near a companion galaxy. 
A)  have a central bulge that does not rotate. 
B)  are encompassed within a large lens-shaped disk of dark matter. 
C)  are orbited by globular clusters that also exhibit star formation. 
D)  are most often near a companion galaxy.

Question 11

What name is given to a galaxy with a smooth distribution of brightness and a round shape?

Accepted Answer

A)  SBa 
B)  Sa 
C)  E7 
D)  E0 
A)  SBa 
B)  Sa 
C)  E7 
D)  E0

Question 12

What name is given to a galaxy with a smooth distribution of brightness and a very elongated shape?

Accepted Answer

A)  Sc 
B)  SBc 
C)  E0 
D)  E7 
A)  Sc 
B)  SBc 
C)  E0 
D)  E7

Question 13

The Magellanic Clouds as seen from the southern hemisphere are examples of what type of objects?

Accepted Answer

A)  irregular galaxies 
B)  supernova remnants 
C)  planetary nebulae 
D)  spiral galaxies 
A)  irregular galaxies 
B)  supernova remnants 
C)  planetary nebulae 
D)  spiral galaxies

Question 14

Which of these techniques has NOT provided a means by which astronomers can infer the presence of dark matter in the universe?

Accepted Answer

A)  measurement of the orbital speeds of stars near possible supermassive black holes at the centers of galaxies 
B)  measurement of the orbital speeds of stars in the outer regions of galaxies 
C)  observation of the bending of light (gravitational lensing) from remote galaxies as it passes through intervening clusters of galaxies 
D)  measurement of the line-of-sight speeds of individual galaxies in clusters of galaxies 
A)  measurement of the orbital speeds of stars near possible supermassive black holes at the centers of galaxies 
B)  measurement of the orbital speeds of stars in the outer regions of galaxies 
C)  observation of the bending of light (gravitational lensing) from remote galaxies as it passes through intervening clusters of galaxies 
D)  measurement of the line-of-sight speeds of individual galaxies in clusters of galaxies

Question 15

What type of galaxy has a nuclear region of more or less uniform brightness from which long lanes of stars curve outward?

Accepted Answer

A)  spiral 
B)  quasar 
C)  irregular 
D)  elliptical 
A)  spiral 
B)  quasar 
C)  irregular 
D)  elliptical

Question 16

According to the Hubble classification scheme, an E6 galaxy

Accepted Answer

A)  has more tightly wound spiral arms than an E2 galaxy. 
B)  has a shorter central bar in its disk than an E2 galaxy. 
C)  is rounder-looking than an E2 galaxy. 
D)  is more elongated than an E2 galaxy. 
A)  has more tightly wound spiral arms than an E2 galaxy. 
B)  has a shorter central bar in its disk than an E2 galaxy. 
C)  is rounder-looking than an E2 galaxy. 
D)  is more elongated than an E2 galaxy.

Question 17

The source of the hot, intergalactic gas in many rich, regular clusters of galaxies appears to be

Accepted Answer

A)  jets of gas ejected by supermassive black holes at the centers of the galaxies. 
B)  bursts of star formation in merging galaxies. 
C)  exploding stars or supernovae within individual galaxies. 
D)  collisions between galaxies in the cluster. 
A)  jets of gas ejected by supermassive black holes at the centers of the galaxies. 
B)  bursts of star formation in merging galaxies. 
C)  exploding stars or supernovae within individual galaxies. 
D)  collisions between galaxies in the cluster.

Question 18

Which two quantities are shown to be related to one another in Hubble's law?

Accepted Answer

A)  distance and brightness 
B)  brightness and the width of the 21-cm radio emission line of hydrogen 
C)  brightness and recession velocity 
D)  distance and redshift of light from the object 
A)  distance and brightness 
B)  brightness and the width of the 21-cm radio emission line of hydrogen 
C)  brightness and recession velocity 
D)  distance and redshift of light from the object

Question 19

In spiral galaxies, the tightness of the winding of the spiral arms appears to be related directly to the

Accepted Answer

A)  age of the galaxy, as determined from the age of its individual stars. 
B)  number of globular clusters in the halo of the galaxy. 
C)  overall intrinsic size of the galaxy, or the diameter across the spiral arms. 
D)  size of the central bulge of the galaxy. 
A)  age of the galaxy, as determined from the age of its individual stars. 
B)  number of globular clusters in the halo of the galaxy. 
C)  overall intrinsic size of the galaxy, or the diameter across the spiral arms. 
D)  size of the central bulge of the galaxy.

Question 20

The temperature of the hot intergalactic gas that results from the merger of galaxies can range from 300,000 to 5 million K. What is the BEST electromagnetic radiation range in which to view this hot gas?

Accepted Answer

A)  X-ray 
B)  visible 
C)  infrared 
D)  radio 
A)  X-ray 
B)  visible 
C)  infrared 
D)  radio

On the Hubble tuning-fork diagram shown in Figure 17-15 of the text, the irregular galaxies are placed between the tines at the right end of the diagram. Why is this?

The Hubble law states that

A supercluster of galaxies is a

The Hubble flow, demonstrating the expansion of the universe, occurs

The Tully-Fisher relationship can be used to measure the luminosity of (and thus the distance to)

What is the classification for a spiral galaxy with a large nuclear region and tightly wound arms?

In the verification of the Hubble law for the expansion of the universe and the determination of the constant H₀, the greatest difficulty has been

Arrange these objects according to size, largest to smallest.

The Milky Way Galaxy is a(n)

Grand-design spiral galaxies

What name is given to a galaxy with a smooth distribution of brightness and a round shape?

What name is given to a galaxy with a smooth distribution of brightness and a very elongated shape?

The Magellanic Clouds as seen from the southern hemisphere are examples of what type of objects?

Which of these techniques has NOT provided a means by which astronomers can infer the presence of dark matter in the universe?

What type of galaxy has a nuclear region of more or less uniform brightness from which long lanes of stars curve outward?

According to the Hubble classification scheme, an E6 galaxy

The source of the hot, intergalactic gas in many rich, regular clusters of galaxies appears to be

Which two quantities are shown to be related to one another in Hubble's law?

In spiral galaxies, the tightness of the winding of the spiral arms appears to be related directly to the

The temperature of the hot intergalactic gas that results from the merger of galaxies can range from 300,000 to 5 million K. What is the BEST electromagnetic radiation range in which to view this hot gas?

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Atomic Physics and Spectra

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

Earth and the Moon

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Quasars and Other Active Galaxies

Cosmology

Astrobiology

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Exam 17: Galaxies

On the Hubble tuning-fork diagram shown in Figure 17-15 of the text, the irregular galaxies are placed between the tines at the right end of the diagram. Why is this?

The Hubble law states that

A supercluster of galaxies is a

The Hubble flow, demonstrating the expansion of the universe, occurs

The Tully-Fisher relationship can be used to measure the luminosity of (and thus the distance to)

What is the classification for a spiral galaxy with a large nuclear region and tightly wound arms?

In the verification of the Hubble law for the expansion of the universe and the determination of the constant H0, the greatest difficulty has been

Arrange these objects according to size, largest to smallest.

The Milky Way Galaxy is a(n)

Grand-design spiral galaxies

What name is given to a galaxy with a smooth distribution of brightness and a round shape?

What name is given to a galaxy with a smooth distribution of brightness and a very elongated shape?

The Magellanic Clouds as seen from the southern hemisphere are examples of what type of objects?

Which of these techniques has NOT provided a means by which astronomers can infer the presence of dark matter in the universe?

What type of galaxy has a nuclear region of more or less uniform brightness from which long lanes of stars curve outward?

According to the Hubble classification scheme, an E6 galaxy

The source of the hot, intergalactic gas in many rich, regular clusters of galaxies appears to be

Which two quantities are shown to be related to one another in Hubble's law?

In spiral galaxies, the tightness of the winding of the spiral arms appears to be related directly to the

The temperature of the hot intergalactic gas that results from the merger of galaxies can range from 300,000 to 5 million K. What is the BEST electromagnetic radiation range in which to view this hot gas?

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Atomic Physics and Spectra

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

Earth and the Moon

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Quasars and Other Active Galaxies

Cosmology

Astrobiology

Filters

In the verification of the Hubble law for the expansion of the universe and the determination of the constant H₀, the greatest difficulty has been