Question 1

What is true of spiral galaxies?

Accepted Answer

A)  They are much less common at larger redshifts. 
B)  They are relatively rare in regions of high galaxy density. 
C)  They are only found in the center of rich galaxy clusters. 
D)  They have never been seen to have large redshifts. 
E)  They evolve from giant ellipticals. 
A)  They are much less common at larger redshifts. 
B)  They are relatively rare in regions of high galaxy density. 
C)  They are only found in the center of rich galaxy clusters. 
D)  They have never been seen to have large redshifts. 
E)  They evolve from giant ellipticals.

Question 2

Collisions between galaxies have little effect on the individual stars.

Accepted Answer

A) True 
 B)False

Question 3

A nearby galaxy has a radius of 4,000 million A.U.and rotates once every 800 million years.What is its mass in solar masses?

Accepted Answer

Using Kepler's third law,P² = a³/(M + m)

Question 4

On average,elliptical galaxies are much older than large spiral galaxies.

Accepted Answer

A) True 
 B)False

Question 5

All of the following are clusters of galaxies EXCEPT:

Accepted Answer

A)  Andromeda. 
B)  Perseus. 
C)  Coma. 
D)  Virgo. 
E)  Hydra. 
A)  Andromeda. 
B)  Perseus. 
C)  Coma. 
D)  Virgo. 
E)  Hydra.

Question 6

Based on galactic rotation curves and cluster dynamics,we think dark matter:

Accepted Answer

A)  is a minor component of the entire mass of the universe. 
B)  is best detected from the X-rays it produces in the intergalactic medium. 
C)  will have no effect on the fate of the universe. 
D)  comprises over 90% of the entire mass of the universe. 
E)  will doom the universe to collapse, overcoming the redshifts we now observe. 
A)  is a minor component of the entire mass of the universe. 
B)  is best detected from the X-rays it produces in the intergalactic medium. 
C)  will have no effect on the fate of the universe. 
D)  comprises over 90% of the entire mass of the universe. 
E)  will doom the universe to collapse, overcoming the redshifts we now observe.

Question 7

A supernova that occurs 10,000 years from now in a galaxy 50,000 light years away:

Accepted Answer

A)  will be observed on Earth 10,000 years from now. 
B)  was observed on Earth 40,000 years ago. 
C)  will be observed on Earth 40,000 years from now. 
D)  was observed on Earth 50,000 years ago. 
E)  will be observed on Earth 50,0000 years from now. 
A)  will be observed on Earth 10,000 years from now. 
B)  was observed on Earth 40,000 years ago. 
C)  will be observed on Earth 40,000 years from now. 
D)  was observed on Earth 50,000 years ago. 
E)  will be observed on Earth 50,0000 years from now.

Question 8

Why is it thought that quasars probably spend only a fairly short time in their highly luminous phase?

Accepted Answer

A)  because there aren't many quasars around today 
B)  because there aren't any quasars closer than about a redshift of 1 
C)  because all quasars are at about the same epoch, narrowly defined in time 
D)  because a black hole could not power a highly luminous quasar for more than a few million years 
E)  because quasars are known to be the consumers of massive galaxies 
A)  because there aren't many quasars around today 
B)  because there aren't any quasars closer than about a redshift of 1 
C)  because all quasars are at about the same epoch, narrowly defined in time 
D)  because a black hole could not power a highly luminous quasar for more than a few million years 
E)  because quasars are known to be the consumers of massive galaxies

Question 9

Gravity lensing lets us map the distribution of both visible and dark matter.

Accepted Answer

A) True 
 B)False

Question 10

The huge,dark,almost spherical regions between the superclusters of galaxies are called ________.

Accepted Answer

The answer of The huge,dark,almost spherical regions between the superclusters...

Question 11

A merger between two large galaxies of comparable size will most likely produce:

Accepted Answer

A)  two small elliptical galaxies. 
B)  a large elliptical galaxy. 
C)  a small elliptical galaxy and a small spiral galaxy. 
D)  a large spiral galaxy. 
E)  a small elliptical galaxy and a large spiral galaxy. 
A)  two small elliptical galaxies. 
B)  a large elliptical galaxy. 
C)  a small elliptical galaxy and a small spiral galaxy. 
D)  a large spiral galaxy. 
E)  a small elliptical galaxy and a large spiral galaxy.

Question 12

On average,the stars in elliptical galaxies are older than the stars in spiral galaxies.

Accepted Answer

A) True 
 B)False

Question 13

The Lyman-alpha "forest" are absorption lines in a quasar spectrum created by all of the gases along the billions of light years its energy has traversed.

Accepted Answer

A) True 
 B)False

Question 14

The type of galaxy where we can track its motion through the intergalactic medium is a:

Accepted Answer

A)  blazar. 
B)  quasar. 
C)  pulsar. 
D)  Head-Tail Radio Galaxy. 
E)  Seyfert galaxy. 
A)  blazar. 
B)  quasar. 
C)  pulsar. 
D)  Head-Tail Radio Galaxy. 
E)  Seyfert galaxy.

Question 15

The largest voids may span 300 million light years across.

Accepted Answer

A) True 
 B)False

Question 16

The quasars with the largest presently known redshifts are close to:

Accepted Answer

A)  0.96. 
B)  3. 
C)  6. 
D)  10. 
E)  65. 
A)  0.96. 
B)  3. 
C)  6. 
D)  10. 
E)  65.

Question 17

Why do almost all active galaxies occur in clusters of galaxies?

Accepted Answer

The conditions for feeding the active ga

Question 18

In its most energetic phase,a quasar can probably only last:

Accepted Answer

A)  a few days. 
B)  a few years. 
C)  a few thousand years. 
D)  a few million years. 
E)  a few billion years. 
A)  a few days. 
B)  a few years. 
C)  a few thousand years. 
D)  a few million years. 
E)  a few billion years.

Question 19

It is now believed the majority of mass for most galaxies lies in their dark halos.

Accepted Answer

A) True 
 B)False

Question 20

Why do we believe galaxy clusters are rich in dark matter?

Accepted Answer

Studies of the gravitational i

Exam 25: Galaxies and Dark Matter: The Large-Scale Structure of the Cosmos

What is true of spiral galaxies?

Collisions between galaxies have little effect on the individual stars.

A nearby galaxy has a radius of 4,000 million A.U.and rotates once every 800 million years.What is its mass in solar masses?

On average,elliptical galaxies are much older than large spiral galaxies.

All of the following are clusters of galaxies EXCEPT:

Based on galactic rotation curves and cluster dynamics,we think dark matter:

A supernova that occurs 10,000 years from now in a galaxy 50,000 light years away:

Why is it thought that quasars probably spend only a fairly short time in their highly luminous phase?

Gravity lensing lets us map the distribution of both visible and dark matter.

The huge,dark,almost spherical regions between the superclusters of galaxies are called ________.

A merger between two large galaxies of comparable size will most likely produce:

On average,the stars in elliptical galaxies are older than the stars in spiral galaxies.

The Lyman-alpha "forest" are absorption lines in a quasar spectrum created by all of the gases along the billions of light years its energy has traversed.

The type of galaxy where we can track its motion through the intergalactic medium is a:

The largest voids may span 300 million light years across.

The quasars with the largest presently known redshifts are close to:

Why do almost all active galaxies occur in clusters of galaxies?

In its most energetic phase,a quasar can probably only last:

It is now believed the majority of mass for most galaxies lies in their dark halos.

Why do we believe galaxy clusters are rich in dark matter?

Charting the Heavens: The Foundations of Astronomy

The Copernican Revolution: The Birth of Modern Science

Radiation: Information from the Cosmos

Spectroscopy: The Inner Workings of Atoms

Telescopes: The Tools of Astronomy

The Solar System: Comparative Planetology and Formation Models

Earth: Our Home in Space

The Moon and Mercury: Scorched and Battered Worlds

Venus: Earth's Sister Planet

Mars: A Near Miss for Life?

Jupiter: Giant of the Solar System

Saturn: Spectacular Rings and Mysterious Moons

Uranus and Neptune: The Outer Worlds of the Solar System

Solar System Debris: Keys to Our Origin

Exoplanets: Planetary Systems Beyond Our Own

The Sun: Our Parent Star

The Stars: Giants,Dwarfs,and the Main Sequence

The Interstellar Medium: Gas and Dust among the Stars

Star Formation: A Traumatic Birth

Stellar Evolution: The Life and Death of a Star

Stellar Explosions: Novae,Supernovae,and the Formation of the Elements

Neutron Stars and Black Holes: Strange States of Matter

The Milky Way Galaxy: A Spiral in Space

Galaxies: Building Blocks of the Universe

Cosmology: The Big Bang and the Fate of the Universe

The Early Universe: Toward the Beginning of Time

Life in the Universe: Are We Alone?

Filters