Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 18, Problem 8E
How do we distinguish stars from brown dwarfs? How do we distinguish brown dwarfs from planets?
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Chapter 18 Solutions
Astronomy
Ch. 18 - How does the mass of the Sun compare with that of...Ch. 18 - Name and describe the three types of binary...Ch. 18 - Describe two ways of determining the diameter of a...Ch. 18 - What are the largest- and smallest-known values of...Ch. 18 - You are able to take spectra of both stars in an...Ch. 18 - Sketch an HR diagram. Label the axes. Show where...Ch. 18 - Describe what a typical star in the Galaxy would...Ch. 18 - How do we distinguish stars from brown dwarfs? How...Ch. 18 - Describe how the mass, luminosity, surface...Ch. 18 - One method to measure the diameter of a star is to...
Ch. 18 - We discussed in the chapter that about half of...Ch. 18 - Is the Sun an average star? Why or why not?Ch. 18 - Suppose you want to determine the average...Ch. 18 - Why do most known visual binaries have relatively...Ch. 18 - Figure 18.11 shows the light curve of a...Ch. 18 - There are fewer eclipsing binaries than...Ch. 18 - Within 50 light-years of the Sun, visual binaries...Ch. 18 - Which is easier to observe at large distances-a...Ch. 18 - The eclipsing binary Algol drops from maximum to...Ch. 18 - Review this spectral data for five stars. Which is...Ch. 18 - Which changes by the largest factor along the main...Ch. 18 - Suppose you want to search for brown dwarfs using...Ch. 18 - An astronomer discovers a type-M star with a large...Ch. 18 - Approximately 6000 stars are bright enough to be...Ch. 18 - Use the data in Appendix J to plot an HR diagram...Ch. 18 - Use the diagram you have drawn for Exercise 18.25...Ch. 18 - Use the data in Appendix I to plot an HR diagram...Ch. 18 - If a visual binary system were to have two...Ch. 18 - Two stars are in a visual binary star system that...Ch. 18 - Describe the spectra for a spectroscopic binary...Ch. 18 - Figure 18.7 shows the velocity of two stars in a...Ch. 18 - You go out stargazing one night, and someone asks...Ch. 18 - If you were to compare three stars with the same...Ch. 18 - Are supergiant stars also extremely massive?...Ch. 18 - Consider the following data on four stars: Which...Ch. 18 - If two stars are in a binary system with a...Ch. 18 - It is possible that stars as much as 200 times the...Ch. 18 - The lowest mass for a true star is 1/12 the mass...Ch. 18 - Spectral types are an indicator of temperature....Ch. 18 - We can estimate the masses of most of the stars in...Ch. 18 - In Diameters of Stars, the relative diameters of...Ch. 18 - Now calculate the radius of Sirius’ white dwarf...Ch. 18 - How does this radius of Sirius B compare with that...Ch. 18 - From the previous calculations and the results...Ch. 18 - How much would you weigh if you were suddenly...Ch. 18 - The star Betelgeuse has a temperature of 3400 K...Ch. 18 - Using the information provided in Table 18.1, what...Ch. 18 - Confirm that the angular diameter of the Sun of...Ch. 18 - An eclipsing binary star system is observed with...Ch. 18 - If a 100 solar mass star were to have a luminosity...Ch. 18 - If Betelgeuse had a mass that was 25 times that of...
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