Essential Cosmic Perspective
9th Edition
ISBN: 9780135795033
Author: Bennett
Publisher: PEARSON
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Chapter 1, Problem 39EAP
Group Activity: Counting the Milky Way’s Stars. Work as a group to answer each part. Note: This activity works particularly well in groups of four students, with each student taking on one of the following roles: scribe: takes notes on the group’s activities; pro-poser: suggests tentative explanations to the group; skeptic: points out weaknesses in proposed explanations; moderator: leads group discussion and makes sure everyone contributes.
a. Work together to estimate the number of stars in the Milky Way from just these two facts: (1) the number of stars within 12 light-years of the Sun, which you can count in Appendix F, and (2) the total volume of the Milky Way’s disk (100,000 light-years in diameter and 1000 light-years thick), which is about 1 billion times the volume of the region of your star count.
b. Discuss how your value from part a compares to the value given in this chapter. Make a list of possible reasons why your technique may have underestimated or overestimated the actual number.
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Chapter 1 Solutions
Essential Cosmic Perspective
Ch. 1 - Prob. 1VSCCh. 1 - Prob. 2VSCCh. 1 - About how far away from Earth would the Sun be...Ch. 1 - Prob. 4VSCCh. 1 - Prob. 1EAPCh. 1 - Define astronomical unit and light-year.Ch. 1 - Explain the statement The farther away we look in...Ch. 1 - Prob. 4EAPCh. 1 - Prob. 5EAPCh. 1 - What do we mean when we say that the universe is...
Ch. 1 - In what sense are we “star stuff”?Ch. 1 - Use the cosmic calendar to describe how the human...Ch. 1 - Briefly explain Earth’s daily rotation and annual...Ch. 1 - Prob. 10EAPCh. 1 - Prob. 11EAPCh. 1 - Prob. 12EAPCh. 1 - Prob. 13EAPCh. 1 - Prob. 14EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 16EAPCh. 1 - Prob. 17EAPCh. 1 - Prob. 18EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 20EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 22EAPCh. 1 - Prob. 23EAPCh. 1 - An astronomical unit is (a) any planet’s average...Ch. 1 - The star Betelgeuse s about 600 light-years away....Ch. 1 - Prob. 26EAPCh. 1 - Prob. 27EAPCh. 1 - Prob. 28EAPCh. 1 - Prob. 29EAPCh. 1 - Prob. 30EAPCh. 1 - Prob. 31EAPCh. 1 - Prob. 32EAPCh. 1 - Prob. 34EAPCh. 1 - Thinking About Scale. One key to success m science...Ch. 1 - Prob. 36EAPCh. 1 - A Human Adventure. Astronomical discoveries...Ch. 1 - Prob. 38EAPCh. 1 - Group Activity: Counting the Milky Way’s Stars....Ch. 1 - Prob. 40EAPCh. 1 - Prob. 41EAPCh. 1 - Prob. 42EAPCh. 1 - Prob. 43EAPCh. 1 - Prob. 44EAPCh. 1 - Moonlight and Sunlight. How long does it take...Ch. 1 - Prob. 46EAPCh. 1 - Driving Trips. Imagine that you could drive your...Ch. 1 - Prob. 48EAPCh. 1 - Prob. 49EAPCh. 1 - Age of the Universe. Suppose we did not yet know...
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