Question 1

According to the Hubble classification scheme, an E4 galaxy has a(n)

Accepted Answer

A)  disk and central bulge with a smooth light distribution and no spiral arms. 
B)  irregular shape. 
C)  round or spherical shape with a smooth light distribution and no disk or central bulge. 
D)  moderately elliptical shape (a flattened circle) with a smooth light distribution. 
A)  disk and central bulge with a smooth light distribution and no spiral arms. 
B)  irregular shape. 
C)  round or spherical shape with a smooth light distribution and no disk or central bulge. 
D)  moderately elliptical shape (a flattened circle) with a smooth light distribution.

Question 2

If an astronomer is trying to locate starburst galaxies, which of these would be a good spectral region in which to observe?

Accepted Answer

A)  infrared 
B)  ultraviolet 
C)  X-ray 
D)  gamma ray 
A)  infrared 
B)  ultraviolet 
C)  X-ray 
D)  gamma ray

Question 3

Astronomer A claims that the Hubble constant is 84 km/s per Mpc, while astronomer B claims that it is 63 km/s per Mpc. If, using the Hubble constant, astronomer A claims that a particular galaxy is 4 billion ly away, then astronomer B would claim that it is _____ billion ly away.

Accepted Answer

A)  3 
B)  5.3 
C)  6 
D)  2 
A)  3 
B)  5.3 
C)  6 
D)  2

Question 4

A starburst galaxy appears to be a galaxy in which

Accepted Answer

A)  a collision with another galaxy has produced a burst of star formation. 
B)  most of the energy from the galaxy is being produced by supernovae. 
C)  a central, supermassive black hole is throwing jets of gas and stars out of the nucleus into intergalactic space. 
D)  essentially all the star formation took place in a single, billion-year-long burst early in the life of the galaxy. 
A)  a collision with another galaxy has produced a burst of star formation. 
B)  most of the energy from the galaxy is being produced by supernovae. 
C)  a central, supermassive black hole is throwing jets of gas and stars out of the nucleus into intergalactic space. 
D)  essentially all the star formation took place in a single, billion-year-long burst early in the life of the galaxy.

Question 5

When swirling eddies of gas-rich matter in the universe collide and form a disk centered on an especially massive black hole and lots of dark matter, astronomers believe that this type of galaxy will form.

Accepted Answer

A)  normal spiral 
B)  barred spiral 
C)  giant elliptical 
D)  irregular 
A)  normal spiral 
B)  barred spiral 
C)  giant elliptical 
D)  irregular

Question 6

The mass of the presently observable matter in a typical rich cluster of galaxies appears to be approximately what fraction of the mass required to hold the cluster together by gravity?

Accepted Answer

A)  10% 
B)  100%, or the entire galaxy 
C)  about 1% 
D)  90% 
A)  10% 
B)  100%, or the entire galaxy 
C)  about 1% 
D)  90%

Question 7

The Hubble law indicates that

Accepted Answer

A)  the Milky Way Galaxy appears to be at or near the center of the known universe. 
B)  all nearby superclusters of galaxies are moving toward Earth and all faraway superclusters are moving away from Earth. 
C)  the farther superclusters are receding faster than the nearby superclusters. 
D)  the universe will expand forever. 
A)  the Milky Way Galaxy appears to be at or near the center of the known universe. 
B)  all nearby superclusters of galaxies are moving toward Earth and all faraway superclusters are moving away from Earth. 
C)  the farther superclusters are receding faster than the nearby superclusters. 
D)  the universe will expand forever.

Question 8

Which of these galaxy types contain little or no interstellar dust or gas?

Accepted Answer

A)  ellipticals 
B)  barred spirals 
C)  irregulars 
D)  spirals 
A)  ellipticals 
B)  barred spirals 
C)  irregulars 
D)  spirals

Question 9

Galaxies throughout the universe appear to be distributed

Accepted Answer

A)  mostly in a single spherical shell surrounding a void in space presumed to have been caused by a vast explosion at the time of the Big Bang. 
B)  around a single point in space, the presumed location of the original Big Bang that created the universe. 
C)  in groups and filaments surrounding vast voids. 
D)  uniformly throughout space. 
A)  mostly in a single spherical shell surrounding a void in space presumed to have been caused by a vast explosion at the time of the Big Bang. 
B)  around a single point in space, the presumed location of the original Big Bang that created the universe. 
C)  in groups and filaments surrounding vast voids. 
D)  uniformly throughout space.

Question 10

What mechanism is believed to produce flocculent spiral galaxies?

Accepted Answer

A)  satellite galaxies plunging through the disk of the nuclear spiral galaxy 
B)  self-propagating star formation, where star formation occurs in bursts 
C)  shock waves from explosive star formation in the nuclear bulge 
D)  density waves in the interstellar medium 
A)  satellite galaxies plunging through the disk of the nuclear spiral galaxy 
B)  self-propagating star formation, where star formation occurs in bursts 
C)  shock waves from explosive star formation in the nuclear bulge 
D)  density waves in the interstellar medium

Question 11

What is the famous Virgo cluster of galaxies?

Accepted Answer

A)  rich, irregular cluster of over 1000 galaxies 
B)  cluster of unknown type centered on a quasar near the edge of the visible universe 
C)  rich, regular cluster of thousands of galaxies 
D)  nearest cluster beyond the Local Group containing about three dozen galaxies 
A)  rich, irregular cluster of over 1000 galaxies 
B)  cluster of unknown type centered on a quasar near the edge of the visible universe 
C)  rich, regular cluster of thousands of galaxies 
D)  nearest cluster beyond the Local Group containing about three dozen galaxies

Question 12

Galaxies in the universe are

Accepted Answer

A)  distributed randomly, their density remaining approximately constant throughout space. 
B)  collected into superclusters that are concentrated along filaments surrounding empty spaces that contain very few galaxies. 
C)  concentrated into a central supercluster with other clusters rotating about it in a huge, flat disk like a supergalaxy, with very few galaxies outside this disk. 
D)  all concentrated in spherical clusters, and these clusters are distributed uniformly throughout space. 
A)  distributed randomly, their density remaining approximately constant throughout space. 
B)  collected into superclusters that are concentrated along filaments surrounding empty spaces that contain very few galaxies. 
C)  concentrated into a central supercluster with other clusters rotating about it in a huge, flat disk like a supergalaxy, with very few galaxies outside this disk. 
D)  all concentrated in spherical clusters, and these clusters are distributed uniformly throughout space.

Question 13

In which of these ways is the Milky Way Galaxy different from most spiral galaxies?

Accepted Answer

A)  The Milky Way has only three spiral arms, whereas most spiral galaxies have at least four. 
B)  The Milky Way has only two spiral arms, whereas most galaxies have at least four. 
C)  The spiral arms of the Milky Way are far more tightly wound than those in most galaxies. 
D)  The Milky Way has at least four spiral arms, whereas most spiral galaxies have only two. 
A)  The Milky Way has only three spiral arms, whereas most spiral galaxies have at least four. 
B)  The Milky Way has only two spiral arms, whereas most galaxies have at least four. 
C)  The spiral arms of the Milky Way are far more tightly wound than those in most galaxies. 
D)  The Milky Way has at least four spiral arms, whereas most spiral galaxies have only two.

Question 14

What is the basic shape of a spiral galaxy?

Accepted Answer

A)  round, flat disk with long lanes of stars that curve outward from a round, nuclear region bulging out of the disk 
B)  round, flat disk with long lanes of stars that curve outward from the center of the galaxy 
C)  approximately spherical with long lanes of dark dust clouds curving through it in a spiral pattern 
D)  round, thin disk of uniform brightness with its edges bent up and down into a spiral shape 
A)  round, flat disk with long lanes of stars that curve outward from a round, nuclear region bulging out of the disk 
B)  round, flat disk with long lanes of stars that curve outward from the center of the galaxy 
C)  approximately spherical with long lanes of dark dust clouds curving through it in a spiral pattern 
D)  round, thin disk of uniform brightness with its edges bent up and down into a spiral shape

Question 15

Clusters of galaxies can be rich or poor, regular or irregular. But one thing they all have in common is that, if all galaxies could be detected, the majority of galaxies would be

Accepted Answer

A)  normal spirals. 
B)  ellipticals. 
C)  irregulars. 
D)  barred spirals. 
A)  normal spirals. 
B)  ellipticals. 
C)  irregulars. 
D)  barred spirals.

Question 16

A particular galaxy appears round, with a nuclear region of uniform brightness and an outer region that is broken up into long, curved, well-defined lanes of stars and light gas clouds. How would this galaxy be classified?

Accepted Answer

A)  elliptical 
B)  flocculent spiral 
C)  irregular 
D)  grand-design spiral 
A)  elliptical 
B)  flocculent spiral 
C)  irregular 
D)  grand-design spiral

Question 17

How has the hot, X-ray-emitting intergalactic gas in galaxy clusters affected the dark matter problem for the clusters?

Accepted Answer

A)  The gas supplies the mass needed to solve the problem, which is now no longer a problem! 
B)  The gas supplies about 10 times too much mass-now the problem is how clusters so massive are not much more compact. 
C)  The gas supplies about 2/10 of the dark matter, so with the visible matter, about 7/10 of the mass required to stabilize the cluster is still missing. 
D)  The gas is very tenuous and supplies almost no mass at all; therefore, it has almost no effect on the dark matter problem. 
A)  The gas supplies the mass needed to solve the problem, which is now no longer a problem! 
B)  The gas supplies about 10 times too much mass-now the problem is how clusters so massive are not much more compact. 
C)  The gas supplies about 2/10 of the dark matter, so with the visible matter, about 7/10 of the mass required to stabilize the cluster is still missing. 
D)  The gas is very tenuous and supplies almost no mass at all; therefore, it has almost no effect on the dark matter problem.

Question 18

How many stars per cubic parsec are there in the spiral arms of a spiral galaxy compared with the regions between the spiral arms?

Accepted Answer

A)  The density of stars inside spiral arms is more than 100 times that in the regions between the arms. 
B)  The density of stars inside spiral arms is about twice that in the regions between the arms. 
C)  There are a lot of stars in the spiral arms and none at all in the regions between the arms. 
D)  The density of stars inside spiral arms is about 5% more than in the regions between the arms. 
A)  The density of stars inside spiral arms is more than 100 times that in the regions between the arms. 
B)  The density of stars inside spiral arms is about twice that in the regions between the arms. 
C)  There are a lot of stars in the spiral arms and none at all in the regions between the arms. 
D)  The density of stars inside spiral arms is about 5% more than in the regions between the arms.

Question 19

How are galaxies spread throughout the universe?

Accepted Answer

A)  Galaxies are densest near the Milky Way Galaxy and become less and less numerous the farther one looks out into the universe. 
B)  Galaxies are grouped in clusters that are spread more or less evenly throughout the universe. 
C)  Galaxies are spread more or less evenly throughout the universe. 
D)  Clusters of galaxies exist that are themselves often clustered into superclusters. Clusters and superclusters appear to be distributed around giant empty voids. 
A)  Galaxies are densest near the Milky Way Galaxy and become less and less numerous the farther one looks out into the universe. 
B)  Galaxies are grouped in clusters that are spread more or less evenly throughout the universe. 
C)  Galaxies are spread more or less evenly throughout the universe. 
D)  Clusters of galaxies exist that are themselves often clustered into superclusters. Clusters and superclusters appear to be distributed around giant empty voids.

Question 20

Who first showed that the recessional speeds of galaxies increase with increasing distance from Earth?

Accepted Answer

A)  V. M. Slipher 
B)  Karl Jansky 
C)  Edwin Hubble 
D)  Albert Einstein 
A)  V. M. Slipher 
B)  Karl Jansky 
C)  Edwin Hubble 
D)  Albert Einstein

According to the Hubble classification scheme, an E4 galaxy has a(n)

If an astronomer is trying to locate starburst galaxies, which of these would be a good spectral region in which to observe?

Astronomer A claims that the Hubble constant is 84 km/s per Mpc, while astronomer B claims that it is 63 km/s per Mpc. If, using the Hubble constant, astronomer A claims that a particular galaxy is 4 billion ly away, then astronomer B would claim that it is _____ billion ly away.

A starburst galaxy appears to be a galaxy in which

When swirling eddies of gas-rich matter in the universe collide and form a disk centered on an especially massive black hole and lots of dark matter, astronomers believe that this type of galaxy will form.

The mass of the presently observable matter in a typical rich cluster of galaxies appears to be approximately what fraction of the mass required to hold the cluster together by gravity?

The Hubble law indicates that

Which of these galaxy types contain little or no interstellar dust or gas?

Galaxies throughout the universe appear to be distributed

What mechanism is believed to produce flocculent spiral galaxies?

What is the famous Virgo cluster of galaxies?

Galaxies in the universe are

In which of these ways is the Milky Way Galaxy different from most spiral galaxies?

What is the basic shape of a spiral galaxy?

Clusters of galaxies can be rich or poor, regular or irregular. But one thing they all have in common is that, if all galaxies could be detected, the majority of galaxies would be

A particular galaxy appears round, with a nuclear region of uniform brightness and an outer region that is broken up into long, curved, well-defined lanes of stars and light gas clouds. How would this galaxy be classified?

How has the hot, X-ray-emitting intergalactic gas in galaxy clusters affected the dark matter problem for the clusters?

How many stars per cubic parsec are there in the spiral arms of a spiral galaxy compared with the regions between the spiral arms?

How are galaxies spread throughout the universe?

Who first showed that the recessional speeds of galaxies increase with increasing distance from Earth?

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

Exam 17: Galaxies

According to the Hubble classification scheme, an E4 galaxy has a(n)

If an astronomer is trying to locate starburst galaxies, which of these would be a good spectral region in which to observe?

Astronomer A claims that the Hubble constant is 84 km/s per Mpc, while astronomer B claims that it is 63 km/s per Mpc. If, using the Hubble constant, astronomer A claims that a particular galaxy is 4 billion ly away, then astronomer B would claim that it is _____ billion ly away.

A starburst galaxy appears to be a galaxy in which

When swirling eddies of gas-rich matter in the universe collide and form a disk centered on an especially massive black hole and lots of dark matter, astronomers believe that this type of galaxy will form.

The mass of the presently observable matter in a typical rich cluster of galaxies appears to be approximately what fraction of the mass required to hold the cluster together by gravity?

The Hubble law indicates that

Which of these galaxy types contain little or no interstellar dust or gas?

Galaxies throughout the universe appear to be distributed

What mechanism is believed to produce flocculent spiral galaxies?

What is the famous Virgo cluster of galaxies?

Galaxies in the universe are

In which of these ways is the Milky Way Galaxy different from most spiral galaxies?

What is the basic shape of a spiral galaxy?

Clusters of galaxies can be rich or poor, regular or irregular. But one thing they all have in common is that, if all galaxies could be detected, the majority of galaxies would be

A particular galaxy appears round, with a nuclear region of uniform brightness and an outer region that is broken up into long, curved, well-defined lanes of stars and light gas clouds. How would this galaxy be classified?

How has the hot, X-ray-emitting intergalactic gas in galaxy clusters affected the dark matter problem for the clusters?

How many stars per cubic parsec are there in the spiral arms of a spiral galaxy compared with the regions between the spiral arms?

How are galaxies spread throughout the universe?

Who first showed that the recessional speeds of galaxies increase with increasing distance from Earth?

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