The Cosmic Perspective (9th Edition)
9th Edition
ISBN: 9780134874364
Author: Jeffrey O. Bennett, Megan O. Donahue, Nicholas Schneider, Mark Voit
Publisher: PEARSON
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Chapter 22, Problem 51EAP
To determine
The peak wavelength and corresponding temperature.
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The Milky Way grew through merging with many smaller galaxies. What are the observational signatures of this process?
O The motion of old stars in the bulge and halo of our galaxy are randomly orientated, meaning they were formed from collisions of small,
accreted, galaxies all on different paths.
O The ordered motion of the bulge / halo stars means that they came from many objects.
The random motions of stars in the disk means it was formed from collisions of small, accreted, galaxies.
O The motion of young stars in the disk are all in the same direction, meaning they came in as seperate objects.
An astronomer observed the motions of some galaxies. Based on his observations, he made the following statements. Which one of them is most likely to be false? Take Hubble's constant to be 67 km/s/Mpc.
A. A galaxy observed to be moving away from us at a speed of 70 km/s is at a distance of about 1 Mpc from us.
B. A galaxy observed to be moving away from us at a speed of 700 km/s is at a distance of about 10 Mpc from us.
C. A galaxy observed to be moving away from us at a speed of 7000 km/s is at a distance of about 100 Mpc from us.
D. A galaxy observed to be moving away from us at a speed of 70000 km/s is at a distance of about 1 Gpc from us.
Is the answer D? Thank you!
1. The current (critical) density of our universe is pe = 10-26kg/m³. Assume the universe is
filled with cubes with equal size that each contain one person of m = 100kg. What would
the length of the side of such a cube have to be in order to give the correct critical density?
How many hydrogen atoms would you need in a box of 1 m³ to reach the critical density?
The matter we know, which consists mostly of hydrogen, constitutes only 4.8% of the current
critical energy density of our universe. So how many hydrogen atoms are actually in a box
of 1 m3 in our universe? Deep space is very empty and a much better vacuum than we can
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Chapter 22 Solutions
The Cosmic Perspective (9th Edition)
Ch. 22 - Prob. 1VSCCh. 22 - Prob. 2VSCCh. 22 - Prob. 3VSCCh. 22 - Explain what we mean by the Big Bang theory.Ch. 22 - Prob. 2EAPCh. 22 - Prob. 3EAPCh. 22 - Prob. 4EAPCh. 22 - Prob. 5EAPCh. 22 - Prob. 6EAPCh. 22 - Prob. 7EAP
Ch. 22 - 8. Why do we think there was slightly more matter...Ch. 22 - 9. How long did the era of nucleosynthesis last?...Ch. 22 - 10. When we observe the cosmic microwave...Ch. 22 - 11. Briefly describe how the cosmic microwave...Ch. 22 - 12. How does the chemical abundance of helium in...Ch. 22 - Prob. 13EAPCh. 22 - Prob. 14EAPCh. 22 - Prob. 15EAPCh. 22 - Prob. 16EAPCh. 22 - Prob. 17EAPCh. 22 - Decide whether the statement makes sense (or is...Ch. 22 - Prob. 19EAPCh. 22 - Prob. 20EAPCh. 22 - Prob. 21EAPCh. 22 - Prob. 22EAPCh. 22 - Prob. 23EAPCh. 22 - Prob. 24EAPCh. 22 - Decide whether the statement makes sense (or is...Ch. 22 - Choose the best answer to each of the following....Ch. 22 - Prob. 27EAPCh. 22 - Prob. 28EAPCh. 22 - Prob. 29EAPCh. 22 - Prob. 30EAPCh. 22 - Prob. 31EAPCh. 22 - Prob. 32EAPCh. 22 - Prob. 33EAPCh. 22 - Prob. 34EAPCh. 22 - Prob. 35EAPCh. 22 - Prob. 37EAPCh. 22 - Prob. 38EAPCh. 22 - Prob. 41EAPCh. 22 - Prob. 42EAPCh. 22 - Prob. 43EAPCh. 22 - Prob. 44EAPCh. 22 - Prob. 45EAPCh. 22 - Prob. 46EAPCh. 22 - Prob. 47EAPCh. 22 - Prob. 48EAPCh. 22 - Prob. 49EAPCh. 22 - Gravity vs. the Electromagnetic Force. The amount...Ch. 22 - Prob. 51EAPCh. 22 - Prob. 52EAPCh. 22 - Prob. 53EAPCh. 22 - Prob. 54EAPCh. 22 - Daytime at “Night.” According to Olbers’ paradox,...
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