Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Chapter 25, Problem 17E
Suppose that stars evolved without losing mass-that once matter was incorporated into a star, it remained there forever. How would the appearance of the Galaxy be different from what it is now? Would there be population I and population II stars? What other differences would there be?
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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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- Suppose the stars in an elliptical galaxy all formed within a few million years shortly after the universe began. Suppose these stars have a range of masses, just as the stars in our own galaxy do. How would the color of the elliptical change over the next several billion years? How would its luminosity change? Why?arrow_forwardStars form in the Milky Way at a rate of about 1 solar mass per year. At this rate, how long would it take for all the interstellar gas in the Milky Way to be turned into stars if there were no fresh gas coming in from outside? How does this compare to the estimated age of the universe, 14 billion years? What do you conclude from this?arrow_forwardIf the diameter of the Milky Way Galaxys visible disk, 80,000 ly, is represented in a model by a dinner plate with a diameter of 10 inches, what is the model distance to galaxy M31, 2.6 millionly away? What is the model distance to the Virgo galaxy cluster, 16 Mpc away? (Convert answers to feet.)arrow_forward
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