Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 23, Problem 49E
What is the radius of the progenitor star that became SN 1987A? Its luminosity was 100,000 times that of the Sun, and it had a surface temperature of 16,000 K.
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This star has a mass of 3.3 MSun. What is the main sequence lifetime of this star? You may assume that the lifetime of the sun is 1010 yr.
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Chapter 23 Solutions
Astronomy
Ch. 23 - How does a white dwarf differ from a neutron star?...Ch. 23 - Describe the evolution of a star with a mass like...Ch. 23 - Describe the evolution of a massive star (say, 20...Ch. 23 - How do the two types of supernovae discussed in...Ch. 23 - A star begins its life with a mass of 5 MSunbut...Ch. 23 - If the formation of a neutron star leads to a...Ch. 23 - How can the Crab Nebula shine with the energy of...Ch. 23 - How is a nova different from a type Ia supernova?...Ch. 23 - Apart from the masses, how are binary systems with...Ch. 23 - What observations from SN 1987A helped confirm...
Ch. 23 - Describe the evolution of a white dwarf over time,...Ch. 23 - Describe the evolution of a pulsar over time, in...Ch. 23 - How would a white dwarf that formed from a star...Ch. 23 - What do astronomers think are the causes of...Ch. 23 - How did astronomers finally solve the mystery of...Ch. 23 - Arrange the following stars in order of their...Ch. 23 - Would you expect to find any white dwarfs in the...Ch. 23 - Suppose no stars more massive than about 2 MSunhad...Ch. 23 - Would you be more likely to observe a type II...Ch. 23 - Astronomers believe there are something like 100...Ch. 23 - Would you expect to observe every supernova in our...Ch. 23 - The Large Magellanic Cloud has about one-tenth the...Ch. 23 - Look at the list of the nearest stars in Appendix...Ch. 23 - If most stars become white dwarfs at the ends of...Ch. 23 - If a 3 and 8 MSunstar formed together in a binary...Ch. 23 - You have discovered two star clusters. The first...Ch. 23 - A supernova remnant was recently discovered and...Ch. 23 - Based upon the evolution of stars, place the...Ch. 23 - What observations or types of telescopes would you...Ch. 23 - How would the spectra of a type II supernova be...Ch. 23 - The ring around SN 1987A (Figure 23.12) initially...Ch. 23 - What is the acceleration of gravity (g) at the...Ch. 23 - What is the escape velocity from the Sun? How much...Ch. 23 - What is the average density of the Sun? How does...Ch. 23 - Say that a particular white dwarf has the mass of...Ch. 23 - What is the escape velocity from the white dwarf...Ch. 23 - What is the average density of the white dwarf in...Ch. 23 - Now take a neutron star that has twice the mass of...Ch. 23 - What is the escape velocity from the neutron star...Ch. 23 - What is the average density of the neutron star in...Ch. 23 - One way to calculate the radius of a star is to...Ch. 23 - According to a model described in the text, a...Ch. 23 - Do the same calculations as in Exercise 23.42 but...Ch. 23 - If the Sun were replaced by a white dwarf with a...Ch. 23 - A supernova can eject material at a velocity of...Ch. 23 - A supernova remnant was observed in 2007 to be...Ch. 23 - The ring around SN 1987A (Figure 23.12) started...Ch. 23 - Before the star that became SN 1987A exploded, it...Ch. 23 - What is the radius of the progenitor star that...Ch. 23 - What is the acceleration of gravity at the surface...Ch. 23 - What was the escape velocity from the surface of...Ch. 23 - What was the average density of the star that...Ch. 23 - If the pulsar shown in Figure 23.16 is rotating...
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