Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 28, Problem 24E
Assume that dark matter is uniformly distributed throughout the Milky Way, not just in the outer halo but also throughout the bulge and in the disk, where the solar system lives. How much dark matter would you expect there to be inside the solar system? Would you expect that to be easily detectable? Hint: For the radius of the Milky Way’s dark matter halo, use
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A galaxy's rotation curve is a measure of the orbital speed of stars as a function of distance
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The Milky Way galaxy has about 5 x 10⁹ solar masses of gas in total. If 13 solar masses of that gas is turned into stars each year, how many more years could the Milky Way keep up with such a star formation rate?
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B) The nearest large spiral Galaxy, similar in size to the Milky Way, is the Andromeda Galaxy (M31). It is located about 2 million light years from Earth.
C) The disk of the Milky Way galaxy is about 100,000 light years in diameter.
D) On very large scales, matter in the Universe is distributed in clumps and voids.
E) Distances to most stars in the Milky Way are measured by parallax.
F) RR Lyrae and Cepheid variable stars are used to measure the distance to nearby galaxies.
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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