Question 1

Which two energy sources can help a star maintain its internal thermal pressure?

Accepted Answer

A)  nuclear fusion and gravitational contraction 
B)  nuclear fission and gravitational contraction 
C)  nuclear fusion and nuclear fission 
D)  chemical reactions and gravitational contraction 
E)  nuclear fusion and chemical reactions 
A)  nuclear fusion and gravitational contraction 
B)  nuclear fission and gravitational contraction 
C)  nuclear fusion and nuclear fission 
D)  chemical reactions and gravitational contraction 
E)  nuclear fusion and chemical reactions

Question 2

What happens when a star like the sun exhausts its core hydrogen supply?

Accepted Answer

A)  Its core contracts, but its outer layers expand and the star becomes bigger and brighter. 
B)  It contracts, becoming smaller and dimmer. 
C)  It contracts, becoming hotter and brighter. 
D)  It expands, becoming bigger but dimmer. 
E)  Its core contracts, but its outer layers expand and the star becomes bigger but cooler and therefore remains at the same brightness. 
A)  Its core contracts, but its outer layers expand and the star becomes bigger and brighter. 
B)  It contracts, becoming smaller and dimmer. 
C)  It contracts, becoming hotter and brighter. 
D)  It expands, becoming bigger but dimmer. 
E)  Its core contracts, but its outer layers expand and the star becomes bigger but cooler and therefore remains at the same brightness.

Question 3

Briefly summarize the stages of life for a high-mass star.

Accepted Answer

The first stages are similar to those of

Question 4

What can we learn about a star from a life track on an H-R diagram?

Accepted Answer

A)  The surface temperature and luminosity the star will have at each stage of its life 
B)  The star's age 
C)  The star's current stage of life 
D)  How the star's distance from Earth varies at different times in its life 
A)  The surface temperature and luminosity the star will have at each stage of its life 
B)  The star's age 
C)  The star's current stage of life 
D)  How the star's distance from Earth varies at different times in its life

Question 5

How will an isolated, one solar-mass star die?

Accepted Answer

A)  As a white dwarf supernova 
B)  As a white dwarf 
C)  As a neutron star 
D)  As a black hole 
E)  Uncertain, since stars can die in any number of ways. 
A)  As a white dwarf supernova 
B)  As a white dwarf 
C)  As a neutron star 
D)  As a black hole 
E)  Uncertain, since stars can die in any number of ways.

Question 6

Consider the "dead end" element for cores of massive stars: why is that element the "dead end"?

Accepted Answer

A)  It can only release energy by fusion. 
B)  It has the lowest mass per nuclear particle. 
C)  It has the highest nuclear mass. 
D)  It has the lowest nuclear mass. 
E)  It has the highest mass per nuclear particle. F) It can only release energy by fission. 
A)  It can only release energy by fusion. 
B)  It has the lowest mass per nuclear particle. 
C)  It has the highest nuclear mass. 
D)  It has the lowest nuclear mass. 
E)  It has the highest mass per nuclear particle. F) It can only release energy by fission.

Question 7

At approximately what temperature can helium fusion occur?

Accepted Answer

A)  100,000 K 
B)  1 million K 
C)  10 million K 
D)  100 million K 
E)  100 billion K 
A)  100,000 K 
B)  1 million K 
C)  10 million K 
D)  100 million K 
E)  100 billion K

Question 8

Why are elements with even numbers of protons more abundant, on average, than elements with odd numbers of protons?

Accepted Answer

A)  Because elements are mainly made in fusion reactions with hydrogen nuclei 
B)  Because when elements split in a fission reaction, they prefer to split with all the protons paired 
C)  Because elements are mainly made in fusion reactions with helium nuclei 
D)  There's no explanation, it's something of a mystery to be explained or it may be a coincidence. 
A)  Because elements are mainly made in fusion reactions with hydrogen nuclei 
B)  Because when elements split in a fission reaction, they prefer to split with all the protons paired 
C)  Because elements are mainly made in fusion reactions with helium nuclei 
D)  There's no explanation, it's something of a mystery to be explained or it may be a coincidence.

Question 9

If someone somehow added a lot more hydrogen and helium to the Sun (say 50% more than it has now), what would happen to it?

Accepted Answer

A)  It would cease to exist as a star because it would be too diffuse and fluffy. 
B)  Its nuclear reactions would slow down because its heavy element abundance would be relatively less. 
C)  It would explode as a supernova. 
D)  It would increase in size and float away. 
E)  It would begin to evolve much more quickly than it is now. 
A)  It would cease to exist as a star because it would be too diffuse and fluffy. 
B)  Its nuclear reactions would slow down because its heavy element abundance would be relatively less. 
C)  It would explode as a supernova. 
D)  It would increase in size and float away. 
E)  It would begin to evolve much more quickly than it is now.

Question 10

Stars with high masses live longer than stars with lower masses.

Accepted Answer

A) True 
 B)False

Question 11

How many helium nuclei fuse together when making carbon?

Accepted Answer

A)  2 
B)  3 
C)  4 
D)  It varies depending on the reaction 
E)  Helium cannot fuse into carbon 
A)  2 
B)  3 
C)  4 
D)  It varies depending on the reaction 
E)  Helium cannot fuse into carbon

Question 12

Suppose that the star Betelgeuse (the upper left shoulder of Orion) were to supernova tomorrow (as seen here on Earth). What would it look like to the naked eye?

Accepted Answer

A)  Betelgeuse would remain a dot of light, but would suddenly become so bright that, for a few weeks, we'd be able to see this dot in the daytime. 
B)  We'd see a cloud of gas expanding away from the position where Betelgeuse used to be. Over a period of a few weeks, this cloud would fill our entire sky. 
C)  Because the supernova destroys the star, Betelgeuse would suddenly disappear from view. 
D)  Betelgeuse would suddenly appear to grow larger in size, soon reaching the size of the full Moon. It would also be about as bright as the full Moon. 
A)  Betelgeuse would remain a dot of light, but would suddenly become so bright that, for a few weeks, we'd be able to see this dot in the daytime. 
B)  We'd see a cloud of gas expanding away from the position where Betelgeuse used to be. Over a period of a few weeks, this cloud would fill our entire sky. 
C)  Because the supernova destroys the star, Betelgeuse would suddenly disappear from view. 
D)  Betelgeuse would suddenly appear to grow larger in size, soon reaching the size of the full Moon. It would also be about as bright as the full Moon.

Question 13

The luminosity of light emerging from the star's gaseous surface is equal to the . . .

Accepted Answer

A)  star's lifetime. 
B)  mass of the star. 
C)  rate of energy generated from nuclear reactions in the star's core. 
D)  temperature of the star's core. 
E)  star's apparent brightness. 
A)  star's lifetime. 
B)  mass of the star. 
C)  rate of energy generated from nuclear reactions in the star's core. 
D)  temperature of the star's core. 
E)  star's apparent brightness.

Question 14

What is the fate of an isolated brown dwarf?

Accepted Answer

A)  It will become a white dwarf. 
B)  It will become a neutron star. 
C)  It will become a black hole. 
D)  It will slowly evaporate to nothing. 
E)  It will remain a brown dwarf forever. 
A)  It will become a white dwarf. 
B)  It will become a neutron star. 
C)  It will become a black hole. 
D)  It will slowly evaporate to nothing. 
E)  It will remain a brown dwarf forever.

Question 15

Why is Supernova 1987A particularly important to astronomers?

Accepted Answer

A)  It is the nearest supernova to have occurred at a time when we were capable of studying it carefully with telescopes. 
B)  It was the first supernova detected in nearly 400 years. 
C)  It provided the first evidence that supernovae really occur. 
D)  It occurred only a few light-years from Earth. 
A)  It is the nearest supernova to have occurred at a time when we were capable of studying it carefully with telescopes. 
B)  It was the first supernova detected in nearly 400 years. 
C)  It provided the first evidence that supernovae really occur. 
D)  It occurred only a few light-years from Earth.

Question 16

What type of star is our Sun?

Accepted Answer

A)  A low-mass star 
B)  An intermediate-mass star 
C)  A high-mass star 
A)  A low-mass star 
B)  An intermediate-mass star 
C)  A high-mass star

Question 17

The interstellar clouds called molecular clouds are ________.

Accepted Answer

A)  the cool clouds in which stars form 
B)  the clouds in which elements such as carbon, nitrogen, and oxygen are made 
C)  clouds that are made mostly of complex molecules such as carbon dioxide and sulfur dioxide 
D)  the hot clouds of gas expelled by dying stars 
A)  the cool clouds in which stars form 
B)  the clouds in which elements such as carbon, nitrogen, and oxygen are made 
C)  clouds that are made mostly of complex molecules such as carbon dioxide and sulfur dioxide 
D)  the hot clouds of gas expelled by dying stars

Question 18

The overall helium fusion reaction is:

Accepted Answer

A)  three helium nuclei fuse to form one carbon nucleus. 
B)  two helium nuclei fuse to form one beryllium nucleus. 
C)  two hydrogen nuclei fuse to form one helium nucleus. 
D)  four helium nuclei fuse to form one oxygen nucleus. 
A)  three helium nuclei fuse to form one carbon nucleus. 
B)  two helium nuclei fuse to form one beryllium nucleus. 
C)  two hydrogen nuclei fuse to form one helium nucleus. 
D)  four helium nuclei fuse to form one oxygen nucleus.

Question 19

The vast majority of stars in a newly formed star cluster are ________.

Accepted Answer

A)  Less massive than the Sun 
B)  Very high-mass, type O and B stars 
C)  Red giants 
D)  About the same mass as our Sun 
A)  Less massive than the Sun 
B)  Very high-mass, type O and B stars 
C)  Red giants 
D)  About the same mass as our Sun

Question 20

Which of the following masses separates low mass stars from high mass stars?

Accepted Answer

A)  About 150 solar masses 
B)  About 50 solar masses 
C)  About 2 solar masses 
D)  About 1 solar mass 
E)  About 0.08 solar masses 
A)  About 150 solar masses 
B)  About 50 solar masses 
C)  About 2 solar masses 
D)  About 1 solar mass 
E)  About 0.08 solar masses

Which two energy sources can help a star maintain its internal thermal pressure?

What happens when a star like the sun exhausts its core hydrogen supply?

Briefly summarize the stages of life for a high-mass star.

What can we learn about a star from a life track on an H-R diagram?

How will an isolated, one solar-mass star die?

Consider the "dead end" element for cores of massive stars: why is that element the "dead end"?

At approximately what temperature can helium fusion occur?

Why are elements with even numbers of protons more abundant, on average, than elements with odd numbers of protons?

If someone somehow added a lot more hydrogen and helium to the Sun (say 50% more than it has now), what would happen to it?

Stars with high masses live longer than stars with lower masses.

How many helium nuclei fuse together when making carbon?

Suppose that the star Betelgeuse (the upper left shoulder of Orion) were to supernova tomorrow (as seen here on Earth). What would it look like to the naked eye?

The luminosity of light emerging from the star's gaseous surface is equal to the . . .

What is the fate of an isolated brown dwarf?

Why is Supernova 1987A particularly important to astronomers?

What type of star is our Sun?

The interstellar clouds called molecular clouds are ________.

The overall helium fusion reaction is:

The vast majority of stars in a newly formed star cluster are ________.

Which of the following masses separates low mass stars from high mass stars?

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Our Star

Surveying the Stars

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Life in the Universe

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Exam 12: Star Stuff

Which two energy sources can help a star maintain its internal thermal pressure?

What happens when a star like the sun exhausts its core hydrogen supply?

Briefly summarize the stages of life for a high-mass star.

What can we learn about a star from a life track on an H-R diagram?

How will an isolated, one solar-mass star die?

Consider the "dead end" element for cores of massive stars: why is that element the "dead end"?

At approximately what temperature can helium fusion occur?

Why are elements with even numbers of protons more abundant, on average, than elements with odd numbers of protons?

If someone somehow added a lot more hydrogen and helium to the Sun (say 50% more than it has now), what would happen to it?

Stars with high masses live longer than stars with lower masses.

How many helium nuclei fuse together when making carbon?

Suppose that the star Betelgeuse (the upper left shoulder of Orion) were to supernova tomorrow (as seen here on Earth). What would it look like to the naked eye?

The luminosity of light emerging from the star's gaseous surface is equal to the . . .

What is the fate of an isolated brown dwarf?

Why is Supernova 1987A particularly important to astronomers?

What type of star is our Sun?

The interstellar clouds called molecular clouds are ________.

The overall helium fusion reaction is:

The vast majority of stars in a newly formed star cluster are ________.

Which of the following masses separates low mass stars from high mass stars?

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Our Star

Surveying the Stars

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Life in the Universe

Filters