Question 1

Which statement does NOT correctly describe typical elliptical galaxies?

Accepted Answer

A)  Typical elliptical galaxies have a central bulge and a disk but no spiral arms. 
B)  Typical elliptical galaxies have a smooth light distribution with various degrees of elongation from a circular shape. 
C)  Typical elliptical galaxies contain primarily low-mass stars. 
D)  Typical elliptical galaxies cover the entire range of masses from the smallest to the largest galaxies in the universe. 
A)  Typical elliptical galaxies have a central bulge and a disk but no spiral arms. 
B)  Typical elliptical galaxies have a smooth light distribution with various degrees of elongation from a circular shape. 
C)  Typical elliptical galaxies contain primarily low-mass stars. 
D)  Typical elliptical galaxies cover the entire range of masses from the smallest to the largest galaxies in the universe.

Question 2

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 3

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 4

The method of stellar parallax:

Accepted Answer

A)  can be used to measure the distance to stars in distant galaxies, just as it can be used for stars in the Milky Way Galaxy. 
B)  can be used for distant galaxies, but only when used with giant molecular clouds (which can be seen at such distances), not with stars. 
C)  cannot be used for distant galaxies because redshift spectra are inherently imprecise at such distances. 
D)  cannot be used for distant galaxies because of the difficulty of resolving the spectra individual stars. 
A)  can be used to measure the distance to stars in distant galaxies, just as it can be used for stars in the Milky Way Galaxy. 
B)  can be used for distant galaxies, but only when used with giant molecular clouds (which can be seen at such distances), not with stars. 
C)  cannot be used for distant galaxies because redshift spectra are inherently imprecise at such distances. 
D)  cannot be used for distant galaxies because of the difficulty of resolving the spectra individual stars.

Question 5

The Hubble distance-velocity relation states that:

Accepted Answer

A)  all objects appear to have the same velocity away from the Sun, regardless of distance from the Sun. 
B)  mutual gravitational attraction of all objects in the universe means that all objects appear to be moving toward the Sun, the closest ones traveling fastest. 
C)  all distant objects are moving toward the Sun, the most distant objects traveling fastest. 
D)  the farther an object is from the Sun, the faster it appears to be moving away from the Sun. 
A)  all objects appear to have the same velocity away from the Sun, regardless of distance from the Sun. 
B)  mutual gravitational attraction of all objects in the universe means that all objects appear to be moving toward the Sun, the closest ones traveling fastest. 
C)  all distant objects are moving toward the Sun, the most distant objects traveling fastest. 
D)  the farther an object is from the Sun, the faster it appears to be moving away from the Sun.

Question 6

Observation of the different components of the Milky Way Galaxy indicates that the spiral arms contain very different populations of stars and other material than those in globular clusters.In what way are they different?

Accepted Answer

A)  Globular clusters contain dust and gas and are the only locations where star formation continues in the Galaxy at the present time. The older stars in the spiral arms have no surrounding dust or gas. 
B)  Spiral arms contain young stars, dust, and gas within which star formation continues, whereas globular clusters contain older star populations, no dust and gas, and no ongoing star formation. 
C)  Spiral arms contain older, more developed and hence brighter and bluer stars, while globular clusters are composed largely of young, red stars in the early stages of formation and development. 
D)  Both spiral arms and globular clusters contain about the same populations of stars both young and old, but, in contrast with the spiral arms, the globular clusters contain no dust or gas, no star formation, and no nova explosions. 
A)  Globular clusters contain dust and gas and are the only locations where star formation continues in the Galaxy at the present time. The older stars in the spiral arms have no surrounding dust or gas. 
B)  Spiral arms contain young stars, dust, and gas within which star formation continues, whereas globular clusters contain older star populations, no dust and gas, and no ongoing star formation. 
C)  Spiral arms contain older, more developed and hence brighter and bluer stars, while globular clusters are composed largely of young, red stars in the early stages of formation and development. 
D)  Both spiral arms and globular clusters contain about the same populations of stars both young and old, but, in contrast with the spiral arms, the globular clusters contain no dust or gas, no star formation, and no nova explosions.

Question 7

Much of the mass of the Milky Way Galaxy appears to be in the form of "dark matter" of unknown composition.At present,dark matter can be detected only because:

Accepted Answer

A)  it emits synchrotron radiation at radio wavelengths. 
B)  its gravitational pull affects orbital motions in the Galaxy. 
C)  it bends light from distant quasars. 
D)  it blocks out the light from distant stars in the plane of the Galaxy. 
A)  it emits synchrotron radiation at radio wavelengths. 
B)  its gravitational pull affects orbital motions in the Galaxy. 
C)  it bends light from distant quasars. 
D)  it blocks out the light from distant stars in the plane of the Galaxy.

Question 8

A spiral galaxy with a bright,starlike nucleus showing strong emission lines is called a:

Accepted Answer

A)  quasar. 
B)  gravitational lens. 
C)  BL Lacertae object. 
D)  Seyfert galaxy. 
A)  quasar. 
B)  gravitational lens. 
C)  BL Lacertae object. 
D)  Seyfert galaxy.

Question 9

Trumpler discovered the effect of interstellar dust by comparing two different distance measurements of distant clusters.The first was based on appearance (concentration of stars toward the center,etc.),which was unaffected by dust.The other was spectroscopic parallax (use of the H-R diagram),which was affected by dust.What should such a comparison show?

Accepted Answer

A)  The H-R diagram should always give larger distances. 
B)  The H-R diagram should always give smaller distances. 
C)  There should be no difference in the distances. 
D)  The distances should be different, but sometimes the H-R diagram should give the larger distance and sometimes the smaller depending on the actual distance to the cluster. 
A)  The H-R diagram should always give larger distances. 
B)  The H-R diagram should always give smaller distances. 
C)  There should be no difference in the distances. 
D)  The distances should be different, but sometimes the H-R diagram should give the larger distance and sometimes the smaller depending on the actual distance to the cluster.

Question 10

In a recent survey of stars in the sky,it was found that occasionally a star that is normally of constant brightness will slowly brighten and then fade back to its original brightness again over the space of several weeks.What is believed to be the cause of this change in brightness?

Accepted Answer

A)  a massive coronal ejection on a star with abnormally strong magnetic fields 
B)  the gradual motion of the star through a break or hole between interstellar dust clouds 
C)  microlensing by compact objects such as brown dwarfs passing in front of the star 
D)  the "lighthouse beam" of a slowly rotating neutron star companion 
A)  a massive coronal ejection on a star with abnormally strong magnetic fields 
B)  the gradual motion of the star through a break or hole between interstellar dust clouds 
C)  microlensing by compact objects such as brown dwarfs passing in front of the star 
D)  the "lighthouse beam" of a slowly rotating neutron star companion

Question 11

Approximately how far is the Sun from the center of the Milky Way Galaxy?

Accepted Answer

A)  2 kpc 
B)  8 kpc 
C)  49 kpc 
D)  160 kpc 
A)  2 kpc 
B)  8 kpc 
C)  49 kpc 
D)  160 kpc

Question 12

Quasars in our universe are:

Accepted Answer

A)  relatively common. Over 10,000 have been identified so far. 
B)  relatively rare. Only about 500 have been detected so far. 
C)  rare. Only about 10 have been positively identified as such by their properties. 
D)  extremely common. At least 1 million have been catalogued so far. 
A)  relatively common. Over 10,000 have been identified so far. 
B)  relatively rare. Only about 500 have been detected so far. 
C)  rare. Only about 10 have been positively identified as such by their properties. 
D)  extremely common. At least 1 million have been catalogued so far.

Question 13

In the mid-nineteenth century,Count Rosse built the world's largest telescope,the "Leviathan of Parsonstown." What major disadvantage did Rosse have in using his telescope at this time?

Accepted Answer

A)  The mirror, although large, was not made using modern techniques. It had so much distortion that deep sky objects like galaxies could not be seen clearly. 
B)  No catalogs of deep sky objects were available, so Rosse did not know where to locate anything of interest. 
C)  The telescope used an objective lens rather than a mirror and thus suffered from distortion due to sagging and chromatic aberration. 
D)  Photography was not available to record the images Rosse observed. 
A)  The mirror, although large, was not made using modern techniques. It had so much distortion that deep sky objects like galaxies could not be seen clearly. 
B)  No catalogs of deep sky objects were available, so Rosse did not know where to locate anything of interest. 
C)  The telescope used an objective lens rather than a mirror and thus suffered from distortion due to sagging and chromatic aberration. 
D)  Photography was not available to record the images Rosse observed.

Question 14

Recent observations seem to indicate that,rather than being a spiral galaxy,the Milky Way may be:

Accepted Answer

A)  a barred spiral with a definite, straight bar across its center. 
B)  an irregular galaxy in which matter is distributed chaotically. 
C)  an elliptical galaxy with little structure. 
D)  two elliptical galaxies colliding with each other, in view of the very active star formation within the galactic plane, brought about by the vastly increased density during the collision. 
A)  a barred spiral with a definite, straight bar across its center. 
B)  an irregular galaxy in which matter is distributed chaotically. 
C)  an elliptical galaxy with little structure. 
D)  two elliptical galaxies colliding with each other, in view of the very active star formation within the galactic plane, brought about by the vastly increased density during the collision.

Question 15

In order to measure the speed of the Sun,we must have a rest frame to use as a reference.What rest frame is used for this measurement?

Accepted Answer

A)  the average velocity of nearby galaxies 
B)  the black hole at the galactic center 
C)  the average velocity of the globular clusters 
D)  cosmic background radiation 
A)  the average velocity of nearby galaxies 
B)  the black hole at the galactic center 
C)  the average velocity of the globular clusters 
D)  cosmic background radiation

Question 16

The 21-cm line is one of the most important wavelengths in radio astronomy.The fact that it is a relatively long wavelength is important because long wavelengths:

Accepted Answer

A)  are more likely to interact with clouds of gas and dust. 
B)  are more likely to pass through clouds of gas and dust. 
C)  carry more energy than short wavelengths of the same energy. 
D)  can be detected with greater resolution than can short wavelengths. 
A)  are more likely to interact with clouds of gas and dust. 
B)  are more likely to pass through clouds of gas and dust. 
C)  carry more energy than short wavelengths of the same energy. 
D)  can be detected with greater resolution than can short wavelengths.

Question 17

Cepheid variable stars are useful to astronomers as indicators of:

Accepted Answer

A)  stars with very high-speed motion. 
B)  white dwarf behavior. 
C)  the existence of black holes. 
D)  distance, particularly to nearby galaxies. 
A)  stars with very high-speed motion. 
B)  white dwarf behavior. 
C)  the existence of black holes. 
D)  distance, particularly to nearby galaxies.

Question 18

In which site in the universe has a supermassive black hole been proposed to account for recent observations?

Accepted Answer

A)  the center of the Milky Way 
B)  the center of the Ring Nebula, a planetary nebula in Lyra 
C)  the center of the universe, where the Big Bang occurred at the beginning of the universe 
D)  the center of the Crab Nebula, an old supernova remnant 
A)  the center of the Milky Way 
B)  the center of the Ring Nebula, a planetary nebula in Lyra 
C)  the center of the universe, where the Big Bang occurred at the beginning of the universe 
D)  the center of the Crab Nebula, an old supernova remnant

Question 19

The method used by Harlow Shapley in 1917 to estimate the Sun's location in the Milky Way Galaxy was the measurement of the:

Accepted Answer

A)  locations of globular clusters around the Galaxy. 
B)  density of stars in different directions along the Milky Way. 
C)  distances to open star clusters and H II regions in the disk of the Galaxy. 
D)  structure of the Andromeda Galaxy and a comparison of it with the structure of the Milky Way. 
A)  locations of globular clusters around the Galaxy. 
B)  density of stars in different directions along the Milky Way. 
C)  distances to open star clusters and H II regions in the disk of the Galaxy. 
D)  structure of the Andromeda Galaxy and a comparison of it with the structure of the Milky Way.

Question 20

What is the MOST outstanding feature of a quasar compared with other objects in deep space?

Accepted Answer

A)  small size 
B)  great distance from Earth 
C)  short lifetime 
D)  prodigious output of energy 
A)  small size 
B)  great distance from Earth 
C)  short lifetime 
D)  prodigious output of energy

Which statement does NOT correctly describe typical elliptical galaxies?

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:

A starburst galaxy appears to be a galaxy in which:

The method of stellar parallax:

The Hubble distance-velocity relation states that:

Observation of the different components of the Milky Way Galaxy indicates that the spiral arms contain very different populations of stars and other material than those in globular clusters.In what way are they different?

Much of the mass of the Milky Way Galaxy appears to be in the form of "dark matter" of unknown composition.At present,dark matter can be detected only because:

A spiral galaxy with a bright,starlike nucleus showing strong emission lines is called a:

In a recent survey of stars in the sky,it was found that occasionally a star that is normally of constant brightness will slowly brighten and then fade back to its original brightness again over the space of several weeks.What is believed to be the cause of this change in brightness?

Approximately how far is the Sun from the center of the Milky Way Galaxy?

Quasars in our universe are:

In the mid-nineteenth century,Count Rosse built the world's largest telescope,the "Leviathan of Parsonstown." What major disadvantage did Rosse have in using his telescope at this time?

Recent observations seem to indicate that,rather than being a spiral galaxy,the Milky Way may be:

In order to measure the speed of the Sun,we must have a rest frame to use as a reference.What rest frame is used for this measurement?

The 21-cm line is one of the most important wavelengths in radio astronomy.The fact that it is a relatively long wavelength is important because long wavelengths:

Cepheid variable stars are useful to astronomers as indicators of:

In which site in the universe has a supermassive black hole been proposed to account for recent observations?

The method used by Harlow Shapley in 1917 to estimate the Sun's location in the Milky Way Galaxy was the measurement of the:

What is the MOST outstanding feature of a quasar compared with other objects in deep space?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

Characterizing Stars

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

Cosmology

Astrobiology

Filters

Exam 13: The Galaxies

Which statement does NOT correctly describe typical elliptical galaxies?

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:

A starburst galaxy appears to be a galaxy in which:

The method of stellar parallax:

The Hubble distance-velocity relation states that:

Observation of the different components of the Milky Way Galaxy indicates that the spiral arms contain very different populations of stars and other material than those in globular clusters.In what way are they different?

Much of the mass of the Milky Way Galaxy appears to be in the form of "dark matter" of unknown composition.At present,dark matter can be detected only because:

A spiral galaxy with a bright,starlike nucleus showing strong emission lines is called a:

In a recent survey of stars in the sky,it was found that occasionally a star that is normally of constant brightness will slowly brighten and then fade back to its original brightness again over the space of several weeks.What is believed to be the cause of this change in brightness?

Approximately how far is the Sun from the center of the Milky Way Galaxy?

Quasars in our universe are:

In the mid-nineteenth century,Count Rosse built the world's largest telescope,the "Leviathan of Parsonstown." What major disadvantage did Rosse have in using his telescope at this time?

Recent observations seem to indicate that,rather than being a spiral galaxy,the Milky Way may be:

In order to measure the speed of the Sun,we must have a rest frame to use as a reference.What rest frame is used for this measurement?

The 21-cm line is one of the most important wavelengths in radio astronomy.The fact that it is a relatively long wavelength is important because long wavelengths:

Cepheid variable stars are useful to astronomers as indicators of:

In which site in the universe has a supermassive black hole been proposed to account for recent observations?

The method used by Harlow Shapley in 1917 to estimate the Sun's location in the Milky Way Galaxy was the measurement of the:

What is the MOST outstanding feature of a quasar compared with other objects in deep space?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

Characterizing Stars

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

Cosmology

Astrobiology

Filters