Question 1

What was the first evidence that quasars were different from astronomical objects before they were observed in visual wavelengths?

Accepted Answer

A)  The first quasars were seen to have fuzz. 
B)  Quasars emitted radio energy like active galaxies, but appeared to be point sources in radio wavelengths. 
C)  Quasars showed significant gravitational lens effects. 
D)  The spectra of quasars looked like that of an M dwarf. 
E)  The larger redshifts originally indicated that they were orbiting the center of the Milky Way. 
A)  The first quasars were seen to have fuzz. 
B)  Quasars emitted radio energy like active galaxies, but appeared to be point sources in radio wavelengths. 
C)  Quasars showed significant gravitational lens effects. 
D)  The spectra of quasars looked like that of an M dwarf. 
E)  The larger redshifts originally indicated that they were orbiting the center of the Milky Way. B

Question 2

Why is the number of galaxies in the Local Group uncertain?

Accepted Answer

Answer not provided.

Question 3

If a quasar has a recessional velocity of 2.7*105 km/s and is determined to be 3600 Mpc, what is the Hubble constant based on this quasar alone? Hint: Not that the units of your result should be (km/s)/Mpc to see what arithmetic process you need to perform.

Accepted Answer

A)  50 km/s/Mpc 
B)  9.7*108 (km/s)Mpc 
C)  75 km/s/Mpc 
D)  0.013 km/s/Mpc 
E)  273,600 km/s/Mpc 
A)  50 km/s/Mpc 
B)  9.7*108 (km/s)Mpc 
C)  75 km/s/Mpc 
D)  0.013 km/s/Mpc 
E)  273,600 km/s/Mpc C

Question 4

The radio lobes that are on each side of some radio galaxies and jets from them produce mainly

Accepted Answer

A)  21-cm radiation. 
B)  synchrotron radiation. 
C)  black body radiation. 
D)  emission lies due to hydrogen. 
E)  absorption lines due to hydrogen. 
A)  21-cm radiation. 
B)  synchrotron radiation. 
C)  black body radiation. 
D)  emission lies due to hydrogen. 
E)  absorption lines due to hydrogen.

Question 5

If H equals 50 km/s/Mpc, then a galaxy with a radial velocity of 50,000 km/s will have a distance of about 1 Mpc.

Accepted Answer

A) True 
 B)False

Question 6

Astronomers now speculate that a galaxy's shape depends on all of the following except

Accepted Answer

A)  the rate of star formation. 
B)  the history of past collisions. 
C)  the mass. 
D)  All of these may be important in determining a galaxy's shape. 
A)  the rate of star formation. 
B)  the history of past collisions. 
C)  the mass. 
D)  All of these may be important in determining a galaxy's shape.

Question 7

The Milky Way galaxy is not a radio galaxy; it emits no radio radiation.

Accepted Answer

A) True 
 B)False

Question 8

____ galaxies contain large clouds of gas and dust, both young and old stars, but have no obvious spiral arms or nucleus.

Accepted Answer

A)  Irregular 
B)  S0 
C)  E7 
D)  Sa 
E)  E0 
A)  Irregular 
B)  S0 
C)  E7 
D)  Sa 
E)  E0

Question 9

What is the Hubble constant essentially a measure of?

Accepted Answer

A)  the number of galaxies in the universe 
B)  the expansion of the universe 
C)  the age of the Milky Way galaxy 
D)  the amount of dark matter in an average galaxy 
A)  the number of galaxies in the universe 
B)  the expansion of the universe 
C)  the age of the Milky Way galaxy 
D)  the amount of dark matter in an average galaxy

Question 10

Soon after discovery, it was observed that quasars had a starlike appearance which was blurred by Earth's atmospheric "seeing". Despite the blurring, it was realized that the intense energy-emitting regions of quasars must be small because they

Accepted Answer

A)  have high radial velocities. 
B)  are very luminous. 
C)  are surrounded by quasar fuzz. 
D)  radiate huge amounts of energy. 
E)  fluctuate rapidly on time scales as short as a few hours. 
A)  have high radial velocities. 
B)  are very luminous. 
C)  are surrounded by quasar fuzz. 
D)  radiate huge amounts of energy. 
E)  fluctuate rapidly on time scales as short as a few hours.

Question 11

According to the unified model of active galactic nuclei, ____ is in the center surrounded by _________with a Type 1 Seyfert or Type 2 Seyfert being seen depending on the viewing angle.

Accepted Answer

A)  a supermassive black hole; an accretion disk 
B)  a supermassive black hole; empty space 
C)  no black hole; an accretion disk 
D)  no black hole; empty space 
A)  a supermassive black hole; an accretion disk 
B)  a supermassive black hole; empty space 
C)  no black hole; an accretion disk 
D)  no black hole; empty space

Question 12

Edwin Hubble found the Great Nebula in Andromeda (M31 galaxy) to be very far away by

Accepted Answer

A)  comparing absolute to apparent magnitudes of Cepheid variable stars. 
B)  comparing absolute to apparent magnitudes of RR Lyrae variable stars. 
C)  measuring parallaxes of stars in M31. 
D)  getting radar echoes off stars in M31. 
A)  comparing absolute to apparent magnitudes of Cepheid variable stars. 
B)  comparing absolute to apparent magnitudes of RR Lyrae variable stars. 
C)  measuring parallaxes of stars in M31. 
D)  getting radar echoes off stars in M31.

Question 13

Observations of galaxies and clusters of galaxies indicate that about ____ percent of the matter in the universe is dark matter.

Accepted Answer

A)  5 
B)  25 
C)  35 
D)  45 
E)  95 
A)  5 
B)  25 
C)  35 
D)  45 
E)  95

Question 14

Which kind of active galaxies has been observed at the greatest distances from us?

Accepted Answer

A)  Seyfert galaxies 
B)  radio galaxies 
C)  quasars 
A)  Seyfert galaxies 
B)  radio galaxies 
C)  quasars

Question 15

Due to the extremely rapid orbital velocities of material near the center of many galaxies, these galaxies are believed to contain ____________________ at their centers.

Accepted Answer

a supermas

Question 16

All ____ galaxies are spiral galaxies that have small, luminous nuclei.

Accepted Answer

A)  active 
B)  radio 
C)  Seyfert 
D)  double-lobed radio 
E)  blazar 
A)  active 
B)  radio 
C)  Seyfert 
D)  double-lobed radio 
E)  blazar

Question 17

Which of the following is not used as a distance indicator for galaxies?

Accepted Answer

A)  large globular clusters 
B)  Herbig-Haro objects 
C)  H II regions 
D)  cepheid variable stars 
E)  supernovae 
A)  large globular clusters 
B)  Herbig-Haro objects 
C)  H II regions 
D)  cepheid variable stars 
E)  supernovae

Question 18

Galaxies may contain a supermassive black hole at their center but _____ an active nucleus because of _______ into the black hole

Accepted Answer

A)  show; mass inflow 
B)  not show; mass inflow 
C)  show; lack of mass inflow 
A)  show; mass inflow 
B)  not show; mass inflow 
C)  show; lack of mass inflow

Question 19

If Galaxy A is found to have a recessional velocity four times greater than Galaxy B, what can you say about their relative distances from Earth?

Accepted Answer

A)  Galaxy A is four times closer than Galaxy B. 
B)  Galaxy A is four times further away than Galaxy B. 
C)  Galaxy A is twice as distant than Galaxy B. 
D)  Galaxy A is twice as close than Galaxy B. 
A)  Galaxy A is four times closer than Galaxy B. 
B)  Galaxy A is four times further away than Galaxy B. 
C)  Galaxy A is twice as distant than Galaxy B. 
D)  Galaxy A is twice as close than Galaxy B.

Question 20

An irregular galaxy contains mostly

Accepted Answer

A)  lower-main-sequence stars and giants. 
B)  upper-main-sequence stars and giants. 
C)  upper-main-sequence stars and gas and dust. 
D)  upper- and lower-main-sequence stars and gas and dust. 
E)  white dwarfs and supergiants. 
A)  lower-main-sequence stars and giants. 
B)  upper-main-sequence stars and giants. 
C)  upper-main-sequence stars and gas and dust. 
D)  upper- and lower-main-sequence stars and gas and dust. 
E)  white dwarfs and supergiants.

What was the first evidence that quasars were different from astronomical objects before they were observed in visual wavelengths?

Why is the number of galaxies in the Local Group uncertain?

If a quasar has a recessional velocity of 2.7*10⁵ km/s and is determined to be 3600 Mpc, what is the Hubble constant based on this quasar alone? Hint: Not that the units of your result should be (km/s)/Mpc to see what arithmetic process you need to perform.

The radio lobes that are on each side of some radio galaxies and jets from them produce mainly

If H equals 50 km/s/Mpc, then a galaxy with a radial velocity of 50,000 km/s will have a distance of about 1 Mpc.

Astronomers now speculate that a galaxy's shape depends on all of the following except

The Milky Way galaxy is not a radio galaxy; it emits no radio radiation.

____ galaxies contain large clouds of gas and dust, both young and old stars, but have no obvious spiral arms or nucleus.

What is the Hubble constant essentially a measure of?

Soon after discovery, it was observed that quasars had a starlike appearance which was blurred by Earth's atmospheric "seeing". Despite the blurring, it was realized that the intense energy-emitting regions of quasars must be small because they

According to the unified model of active galactic nuclei, is in the center surrounded by _____with a Type 1 Seyfert or Type 2 Seyfert being seen depending on the viewing angle.

Edwin Hubble found the Great Nebula in Andromeda (M31 galaxy) to be very far away by

Observations of galaxies and clusters of galaxies indicate that about ____ percent of the matter in the universe is dark matter.

Which kind of active galaxies has been observed at the greatest distances from us?

Due to the extremely rapid orbital velocities of material near the center of many galaxies, these galaxies are believed to contain ____________________ at their centers.

All ____ galaxies are spiral galaxies that have small, luminous nuclei.

Which of the following is not used as a distance indicator for galaxies?

Galaxies may contain a supermassive black hole at their center but _ an active nucleus because of ___ into the black hole

If Galaxy A is found to have a recessional velocity four times greater than Galaxy B, what can you say about their relative distances from Earth?

An irregular galaxy contains mostly

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Cycles of the Sun and Moon

The Origin of Modern Astronomy

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The Milky Way Galaxy

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Earth and Moon: Bases for Comparative Planetology

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Exam 13: Galaxies: Normal and Active

What was the first evidence that quasars were different from astronomical objects before they were observed in visual wavelengths?

Why is the number of galaxies in the Local Group uncertain?

If a quasar has a recessional velocity of 2.7*105 km/s and is determined to be 3600 Mpc, what is the Hubble constant based on this quasar alone? Hint: Not that the units of your result should be (km/s)/Mpc to see what arithmetic process you need to perform.

The radio lobes that are on each side of some radio galaxies and jets from them produce mainly

If H equals 50 km/s/Mpc, then a galaxy with a radial velocity of 50,000 km/s will have a distance of about 1 Mpc.

Astronomers now speculate that a galaxy's shape depends on all of the following except

The Milky Way galaxy is not a radio galaxy; it emits no radio radiation.

____ galaxies contain large clouds of gas and dust, both young and old stars, but have no obvious spiral arms or nucleus.

What is the Hubble constant essentially a measure of?

Soon after discovery, it was observed that quasars had a starlike appearance which was blurred by Earth's atmospheric "seeing". Despite the blurring, it was realized that the intense energy-emitting regions of quasars must be small because they

According to the unified model of active galactic nuclei, ____ is in the center surrounded by _________with a Type 1 Seyfert or Type 2 Seyfert being seen depending on the viewing angle.

Edwin Hubble found the Great Nebula in Andromeda (M31 galaxy) to be very far away by

Observations of galaxies and clusters of galaxies indicate that about ____ percent of the matter in the universe is dark matter.

Which kind of active galaxies has been observed at the greatest distances from us?

Due to the extremely rapid orbital velocities of material near the center of many galaxies, these galaxies are believed to contain ____________________ at their centers.

All ____ galaxies are spiral galaxies that have small, luminous nuclei.

Which of the following is not used as a distance indicator for galaxies?

Galaxies may contain a supermassive black hole at their center but _____ an active nucleus because of _______ into the black hole

If Galaxy A is found to have a recessional velocity four times greater than Galaxy B, what can you say about their relative distances from Earth?

An irregular galaxy contains mostly

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Formation and Structure of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

If a quasar has a recessional velocity of 2.7*10⁵ km/s and is determined to be 3600 Mpc, what is the Hubble constant based on this quasar alone? Hint: Not that the units of your result should be (km/s)/Mpc to see what arithmetic process you need to perform.

According to the unified model of active galactic nuclei, is in the center surrounded by _____with a Type 1 Seyfert or Type 2 Seyfert being seen depending on the viewing angle.

Galaxies may contain a supermassive black hole at their center but _ an active nucleus because of ___ into the black hole