Question 1

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

Accepted Answer

A) True 
 B)False

Question 2

What is located between the lobes of a double-lobed radio source?

Accepted Answer

A) a pulsar 
B) a galaxy 
C) a galaxy cluster 
D) regions with hot gas but no stars 
A) a pulsar 
B) a galaxy 
C) a galaxy cluster 
D) regions with hot gas but no stars

Question 3

What observational evidence do we have that radio lobes are related to the ejection of gas from galaxies?

Accepted Answer

Radio lobes are large, often symmetrical

Question 4

Why do we expect galaxies to collide fairly often?

Accepted Answer

A) Galaxy separation distances are not that large compared to their sizes. 
B) Galaxies contain large amounts of neutral hydrogen. 
C) Galaxies' large masses cause gravitational attraction. 
D) Galaxies are moving quickly toward each other. 
A) Galaxy separation distances are not that large compared to their sizes. 
B) Galaxies contain large amounts of neutral hydrogen. 
C) Galaxies' large masses cause gravitational attraction. 
D) Galaxies are moving quickly toward each other.

Question 5

Some large clusters of galaxies do not appear to contain enough mass to hold themselves together.

Accepted Answer

A) True 
 B)False

Question 6

Why do astronomers believe that supermassive black holes are the source of energy for active galactic nuclei?

Accepted Answer

A) Such black holes have been found at the centre of most galaxies, both active and inactive. 
B) Radio jets are seen from low mass black holes plus accretion disks inside our galaxy. 
C) Jets and accretion disks have been observed in active galaxies. 
D) Only black holes can produce so much energy in such a small region. 
A) Such black holes have been found at the centre of most galaxies, both active and inactive. 
B) Radio jets are seen from low mass black holes plus accretion disks inside our galaxy. 
C) Jets and accretion disks have been observed in active galaxies. 
D) Only black holes can produce so much energy in such a small region.

Question 7

Observations of galaxies and clusters of galaxies indicate that a percentage of the matter in the universe is dark matter.What is that percentage?

Accepted Answer

A) 5 % 
B) 25 % 
C) 35 % 
D) 95 % 
A) 5 % 
B) 25 % 
C) 35 % 
D) 95 %

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

What is located between the lobes of a double-lobed radio source?

What observational evidence do we have that radio lobes are related to the ejection of gas from galaxies?

Why do we expect galaxies to collide fairly often?

Some large clusters of galaxies do not appear to contain enough mass to hold themselves together.

Why do astronomers believe that supermassive black holes are the source of energy for active galactic nuclei?

Observations of galaxies and clusters of galaxies indicate that a percentage of the matter in the universe is dark matter.What is that percentage?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Structure and Formation of Stars

The Deaths of Stars

The Milky Way Galaxy

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Life on Other Worlds

Filters

Exam 10: Galaxies

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

What is located between the lobes of a double-lobed radio source?

What observational evidence do we have that radio lobes are related to the ejection of gas from galaxies?

Why do we expect galaxies to collide fairly often?

Some large clusters of galaxies do not appear to contain enough mass to hold themselves together.

Why do astronomers believe that supermassive black holes are the source of energy for active galactic nuclei?

Observations of galaxies and clusters of galaxies indicate that a percentage of the matter in the universe is dark matter.What is that percentage?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Structure and Formation of Stars

The Deaths of Stars

The Milky Way Galaxy

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Life on Other Worlds

Filters