Will the Sun shed most of its mass, and, if so, what is that event called?
yes, as a planetary nebula
yes, as a supernova
yes, as a white dwarf
yes, as a neutron blast
no
A white dwarf is composed of primarily
neutrons
hydrogen and helium
iron
cosmic rays
carbon and oxygen
What prevents a neutron star from collapsing?
hydrogen fusion
friction
electron degeneracy pressure
neutron degeneracy pressure
helium fusion
What is the difference between a giant star and a supergiant star?
Why is knowing the temperature in a star’s core so important in determining which nuclear reactions can occur there?
What determines the temperature in the core of a star?
What is a planetary nebula, and how does it form?
What is the Chandrasekhar limit?
What is a neutron star?
Compare a white dwarf and a neutron star. Which of these stellar corpses is more common? Why?
What is the mass range of neutron stars?
Why have searches for supernova remnants at visible wavelengths been less fruitful than searches at other wavelengths?
Why do astronomers believe that pulsars are rapidly rotating neutron stars?
What is the difference between Type Ia and Type II supernovae?
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Compare a nova with a Type Ia supernova. What do they have in common? How are they different?
Describe what X-
Which property, if any, of normal matter ceases to exist in a black hole?
mass
chemical composition
angular momentum
electric charge
All of these properties exist in a black hole.
Supermassive black holes are found in which of the following locations?
in the centers of galaxies
in globular clusters
in open (or galactic) clusters
between galaxies
in orbit with a single star
Which feature is found with Kerr black holes but not Schwarzschild black holes?
a singularity
an event horizon
gravitational redshift of photons outside of the black hole
an ergoregion
warping of nearby spacetime
Under what conditions do all outward pressures on a collapsing star fail to stop its inward motion?
In what way is a black hole blacker than black ink or a black piece of paper?
If the Sun suddenly became a black hole, how would Earth’s orbit be affected?
What are the differences between rotating and nonrotating black holes?
Why are all of the observed stellar-
If light cannot escape from a black hole, how can we detect X-
What prevents thermonuclear reactions from occurring at the center of an isolated white dwarf? If no thermonuclear reactions take place in its core, why doesn’t that body collapse?
Suppose you wanted to determine the age of a planetary nebula. What observations would you make, and how would you use the resulting data?
Why is the rate of expansion of the gas shell in a planetary nebula often not uniform in all directions?
To determine the period of a pulsar accurately, astronomers must take Earth’s orbital motion around the Sun into account. Explain why.
If more massive stars evolve and die before less massive ones, why do some observed black-
Under what circumstances might a neutron star in a binary star system become a black hole?
Which type of black hole, nonrotating or rotating, do science fiction writers use (implicitly) in sending spaceships from one place to another through the hole? Why would the other type not be suitable?
Suppose that you discover a small glowing disk of light while searching the sky with a telescope. How would you determine whether this object was a planetary nebula? What else could this object be?
Describe how astronomers can determine whether a supernova at a known distance is Type Ia or Type II, assuming that they can see the supernova from the time it begins to brighten. There are at least two valid answers to this question.
Describe how astronomers can determine whether a supernova at an unknown distance is Type Ia or Type II.
How will the Sun end its “life cycle”? Will there be anything left of it after fusion in it ceases?
Where was the iron in your blood formed?
What are cosmic rays?
When a star leaves the main sequence, where is the energy being generated that pushes its outer layers outward?
Are black holes completely black (that is, emitting or scattering no light) and are they holes (in the sense of being completely empty)? Explain.
How does the mass of a young black hole compare to the mass of the neutron star from which it just formed?
Are black holes like giant vacuum cleaners in space that are eventually going to suck up everything in the universe? Explain your reasoning.
Which of the following statements most accurately describes the fate of a black hole?
It will remain unchanged as long as the universe exists.
It will eventually suck in everything else in the universe.
It will evaporate.
It will eventually start shining due to fusion in its core.
It will eventually start pulsating by periodically growing larger and then smaller.
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