Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 25, Problem 1E
Explain why we see the Milky Way as a faint band of light stretching across the sky.
Expert Solution & Answer
To determine
To explain:
The reason for the Milky Way to be visible as a faint band of light across the sky.
Explanation of Solution
Milky Way is the home galaxy to the Solar system. Milky Way is a spiral shaped galaxy and contains hundred billion stars. It is about 13.5 billion years old. It is about 30 kpc in diameter.
Solar system lies in the outer regions of the Milky Way in the Orion arm of the Milky Way galaxy. The galactic center if about 8.4kpc away from the Sun.
It is named as Milky Way because of its appearance in the night sky. It appears as a hazy white band of clouds with billions of stars embedded in it. From the Earth, the other arm of the Milky Way is visible. That is why, it appears as a band of stars.
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The figure below shows, at left, a solid disk of radius R = 0.600 m and mass 75.0 kg.
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Chapter 25 Solutions
Astronomy
Ch. 25 - Explain why we see the Milky Way as a faint band...Ch. 25 - Explain where in a spiral galaxy you would expect...Ch. 25 - Describe several characteristics that distinguish...Ch. 25 - Briefly describe the main parts of our Galaxy.Ch. 25 - Describe the evidence indicating that a black hole...Ch. 25 - Explain why the abundances of heavy elements in...Ch. 25 - What will be the long-term future of our Galaxy?Ch. 25 - Suppose the Milky Way was a band of light...Ch. 25 - Suppose somebody proposed that rather than...Ch. 25 - The globular clusters revolve around the Galaxy in...
Ch. 25 - Shapley used the positions of globular clusters to...Ch. 25 - Consider the following five kinds of objects: open...Ch. 25 - The dwarf galaxy in Sagittarius is the one closest...Ch. 25 - Suppose three stars lie in the disk of the Galaxy...Ch. 25 - Why does star formation occur primarily in the...Ch. 25 - Where in the Galaxy would you expect to find Type...Ch. 25 - Suppose that stars evolved without losing...Ch. 25 - Assume that the Sun orbits the center of the...Ch. 25 - The Sun orbits the center of the Galaxy in 225...Ch. 25 - Suppose the Sun orbited a little farther out, but...Ch. 25 - We have said that the Galaxy rotates...Ch. 25 - If our solar system is 4.6 billion years old, how...Ch. 25 - Suppose the average mass of a star in the Galaxy...Ch. 25 - The first clue that the Galaxy contains a lot of...Ch. 25 - The best evidence for a black hole at the center...Ch. 25 - The next step in deciding whether the object in...Ch. 25 - Suppose the Sagittarius dwarf galaxy merges...
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