Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 28, Problem 13E
If we see a double image of a quasar produced by a gravitational lens and can obtain a spectrum of the galaxy that is acting as the gravitational lens, we can then put limits on the distance to the quasar. Explain how.
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Chapter 28 Solutions
Astronomy
Ch. 28 - How are distant (young) galaxies different from...Ch. 28 - What is the evidence that star formation began...Ch. 28 - Describe the evolution of an elliptical galaxy....Ch. 28 - Explain what we mean when we call the universe...Ch. 28 - Describe the organization of galaxies into...Ch. 28 - What is the evidence that a large fraction of the...Ch. 28 - When astronomers make maps of the structure of the...Ch. 28 - How does the presence of an active galactic...Ch. 28 - Describe how you might use the color of a galaxy...Ch. 28 - Suppose a galaxy formed stars for a few million...
Ch. 28 - Given the ideas presented here about how galaxies...Ch. 28 - Can an elliptical galaxy evolve into a spiral?...Ch. 28 - If we see a double image of a quasar produced by a...Ch. 28 - The left panel of Figure 27.1 shows a cluster of...Ch. 28 - Suppose you are standing in the center of a large,...Ch. 28 - Astronomers have been making maps by observing a...Ch. 28 - Human civilization is about 10,000 years old as...Ch. 28 - Given that only about 5% of the galaxies visible...Ch. 28 - Using the information from Example 28.1, how much...Ch. 28 - Using the information from Example 28.1, if...Ch. 28 - Using the information from Example 28.1, how much...Ch. 28 - Galaxies are found in the “walls” of huge voids;...Ch. 28 - Calculate the velocity, the distance, and the...Ch. 28 - Assume that dark matter is uniformly distributed...Ch. 28 - The simulated box of galaxy filaments and...Ch. 28 - The first objects to collapse gravitationally...
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