Question 1

Some quasars show absorption spectra with a smaller redshift than their emission spectra;this indicates that:

Accepted Answer

A) we still don't understand redshifts. 
B) they are much closer than previously thought. 
C) there is cooler gas between us and the quasar. 
D) their black holes are still contracting. 
E) their black holes are still expanding. 
A) we still don't understand redshifts. 
B) they are much closer than previously thought. 
C) there is cooler gas between us and the quasar. 
D) their black holes are still contracting. 
E) their black holes are still expanding.

Question 2

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

Accepted Answer

A) True 
 B)False

Question 3

What is the Great Wall?

Accepted Answer

A) It is a ridge on the Moon near the crater Birt. 
B) It is the distance beyond which astronomers cannot view any more galaxies or even quasars. 
C) It is a large sheet of galaxies measuring 70 Mpc by 200 Mpc. 
D) It is the time before the universe started expanding, about which we can never know anything. 
E) It is an enormous intergalactic cloud of dust and gas that hides more distant galaxies. 
A) It is a ridge on the Moon near the crater Birt. 
B) It is the distance beyond which astronomers cannot view any more galaxies or even quasars. 
C) It is a large sheet of galaxies measuring 70 Mpc by 200 Mpc. 
D) It is the time before the universe started expanding, about which we can never know anything. 
E) It is an enormous intergalactic cloud of dust and gas that hides more distant galaxies.

Question 4

In the Local Group, how might even the Milky Way become a victim?

Accepted Answer

In the binary system of us and Andromeda

Question 5

While yet unseen, some gravitational evidence suggests the existence of dark galaxies.

Accepted Answer

A) True 
 B)False

Question 6

Why is it thought that quasars probably spend only a fairly short time in their highlyluminous 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 millionyears 
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 millionyears 
E) because quasars are known to be the consumers of massive galaxies

Some quasars show absorption spectra with a smaller redshift than their emission spectra;this indicates that:

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

What is the Great Wall?

In the Local Group, how might even the Milky Way become a victim?

While yet unseen, some gravitational evidence suggests the existence of dark galaxies.

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

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: Earths 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

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

Some quasars show absorption spectra with a smaller redshift than their emission spectra;this indicates that:

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

What is the Great Wall?

In the Local Group, how might even the Milky Way become a victim?

While yet unseen, some gravitational evidence suggests the existence of dark galaxies.

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

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: Earths 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