Question 1

The supernova that formed M-1, the Crab Nebula, was observed in:

Accepted Answer

A) 1572 AD by Tycho Brahe. 
B) 1604 AD by Johannes Kepler. 
C) 1054 AD by Chinese and Middle Eastern astronomers. 
D) 1006 by observers in the southern hemisphere. 
E) about 9,000 BC by all our ancestors. 
A) 1572 AD by Tycho Brahe. 
B) 1604 AD by Johannes Kepler. 
C) 1054 AD by Chinese and Middle Eastern astronomers. 
D) 1006 by observers in the southern hemisphere. 
E) about 9,000 BC by all our ancestors.

Question 2

The total energy emitted by the brightest nova explosions is about:

Accepted Answer

A) 1,000 Suns. 
B) 50,000 Suns. 
C) a million Suns. 
D) a billion Suns. 
E) a trillion Suns. 
A) 1,000 Suns. 
B) 50,000 Suns. 
C) a million Suns. 
D) a billion Suns. 
E) a trillion Suns.

Question 3

Except for hydrogen and most of the helium, all the elements have been formed throughstellar nucleosynthesis.

Accepted Answer

A) True 
 B)False

Question 4

What is the only element in your body that was formed during the Big Bang, and not in coresof stars? Explain how you know this.

Accepted Answer

Hydrogen was formed during the

Question 5

An iron core will collapse in approximately one ________ in a Type II supernova event.

Accepted Answer

The answer of An iron core will collapse in approximately...

Question 6

The Crab Nebula is a bright, long-lasting supernova remnant that was made by a ________supernova.

Accepted Answer

The answer of The Crab Nebula is a bright, long-lasting...

Question 7

An iron core cannot support a star because:

Accepted Answer

A) iron is the heaviest element, and sinks upon differentiation. 
B) iron has poor nuclear binding energy. 
C) iron cannot fuse with other nuclei to produce energy. 
D) iron supplies too much pressure. 
E) iron is in the form of a gas, not a solid, in the center of a star. 
A) iron is the heaviest element, and sinks upon differentiation. 
B) iron has poor nuclear binding energy. 
C) iron cannot fuse with other nuclei to produce energy. 
D) iron supplies too much pressure. 
E) iron is in the form of a gas, not a solid, in the center of a star.

Question 8

In a nova, there is a white dwarf, an evolving companion star, and a(n)________ surroundingthe white dwarf's equator.

Accepted Answer

The answer of In a nova, there is a white...

Question 9

Stellar nucleosynthesis is responsible for the existence of all elements except hydrogen.

Accepted Answer

A) True 
 B)False

Question 10

Why are neutrinos from a Type II supernova detected before photons?

Accepted Answer

A) Neutrinos travel faster than photons. 
B) Neutrinos are easier to detect than photons. 
C) Neutrinos are produced in the explosion before photons. 
D) Neutrinos are emitted from the outer part of the star; photons come from the core. 
E) Neutrinos escape from the star quickly because they hardly interact with matter; photons aredelayed by interactions with matter. 
A) Neutrinos travel faster than photons. 
B) Neutrinos are easier to detect than photons. 
C) Neutrinos are produced in the explosion before photons. 
D) Neutrinos are emitted from the outer part of the star; photons come from the core. 
E) Neutrinos escape from the star quickly because they hardly interact with matter; photons aredelayed by interactions with matter.

Question 11

What do X-ray observations tell us about conditions around a potential nova?

Accepted Answer

The mass transfer causes an accretion di

Question 12

The core of a highly evolved high mass star is a little larger than:

Accepted Answer

A) our solar system. 
B) our Sun. 
C) Jupiter. 
D) Earth. 
E) a white dwarf. 
A) our solar system. 
B) our Sun. 
C) Jupiter. 
D) Earth. 
E) a white dwarf.

Question 13

Why does conversion of its core to iron have to mark the end of a star's life? Which stars canend up with iron cores?

Accepted Answer

Stars with a total mass of 8 solar masse

Question 14

The Chandrasekhar Limit is:

Accepted Answer

A) the upper mass limit for a white dwarf. 
B) the temperature at which hydrogen fusion starts. 
C) the temperature at which helium fusion starts. 
D) the point at which a planetary nebula forms. 
E) the lower mass limit for a Type II supernova. 
A) the upper mass limit for a white dwarf. 
B) the temperature at which hydrogen fusion starts. 
C) the temperature at which helium fusion starts. 
D) the point at which a planetary nebula forms. 
E) the lower mass limit for a Type II supernova.

Question 15

What is the CNO cycle and how is it different from hydrogen fusion via the proton-protonchain?

Accepted Answer

The CNO cycle is a kind of hydrogen fusi

Question 16

Compare the amount of time a 20 solar mass star will stay on the main sequence to the lengthof time its iron core can exist.

Accepted Answer

A 20 solar mass star will stay

Question 17

As a star's evolution approaches the Type II supernova, we find:

Accepted Answer

A) the heavier the element, the less time it takes to make it. 
B) the heavier the element, the higher the temperature to fuse it. 
C) helium to carbon fusion takes at least 100 million K to start. 
D) photodisintegration of iron nuclei begins at 10 billion K to ignite the supernova. 
E) All of the above are correct. 
A) the heavier the element, the less time it takes to make it. 
B) the heavier the element, the higher the temperature to fuse it. 
C) helium to carbon fusion takes at least 100 million K to start. 
D) photodisintegration of iron nuclei begins at 10 billion K to ignite the supernova. 
E) All of the above are correct.

Question 18

A carbon-detonation supernova starts out as a white dwarf in a close binary system.

Accepted Answer

A) True 
 B)False

Question 19

For a nova to occur, the system must have already been a(n):

Accepted Answer

A) astrometric binary. 
B) detached binary. 
C) spectroscopic binary. 
D) mass-transfer binary. 
E) eclipsing binary. 
A) astrometric binary. 
B) detached binary. 
C) spectroscopic binary. 
D) mass-transfer binary. 
E) eclipsing binary.

Question 20

Most of the energy released during a supernova is emitted as neutrinos.

Accepted Answer

A) True 
 B)False

Exam 21: Stellar Explosions: Novae, Supernovae, and the Formation of the Elements

The supernova that formed M-1, the Crab Nebula, was observed in:

The total energy emitted by the brightest nova explosions is about:

Except for hydrogen and most of the helium, all the elements have been formed throughstellar nucleosynthesis.

What is the only element in your body that was formed during the Big Bang, and not in coresof stars? Explain how you know this.

An iron core will collapse in approximately one ________ in a Type II supernova event.

The Crab Nebula is a bright, long-lasting supernova remnant that was made by a ________supernova.

An iron core cannot support a star because:

In a nova, there is a white dwarf, an evolving companion star, and a(n)________ surroundingthe white dwarf's equator.

Stellar nucleosynthesis is responsible for the existence of all elements except hydrogen.

Why are neutrinos from a Type II supernova detected before photons?

What do X-ray observations tell us about conditions around a potential nova?

The core of a highly evolved high mass star is a little larger than:

Why does conversion of its core to iron have to mark the end of a star's life? Which stars canend up with iron cores?

The Chandrasekhar Limit is:

What is the CNO cycle and how is it different from hydrogen fusion via the proton-protonchain?

Compare the amount of time a 20 solar mass star will stay on the main sequence to the lengthof time its iron core can exist.

As a star's evolution approaches the Type II supernova, we find:

A carbon-detonation supernova starts out as a white dwarf in a close binary system.

For a nova to occur, the system must have already been a(n):

Most of the energy released during a supernova is emitted as neutrinos.

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

Neutron Stars and Black Holes: Strange States of Matter

The Milky Way Galaxy: a Spiral in Space

Galaxies: Building Blocks of the Universe

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

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