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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Question
Chapter 19, Problem 46EAP
To determine
The type of orbit that the stars probably have around the Milky Way.
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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!
2. A galaxy cluster has a galaxy behind it whose image we see as being smeared out and curved, with an angular radius of curvature on the sky of θE. The background galaxy is at redshift zgal and the cluster is at zclust. What is the mass of the cluster in solar masses? Give your response in scientific notation with one decimal place. (The Hubble constant is of course 70 km/s/Mpc, and you can assume the Hubble law for these low redshifts).
Values:
zgal = 0.11
zclust = 0.07
θE = 117.4 arcseconds
The Tully-Fischer method relies on being able to relate the mass of a galaxy to its rotation velocity.
Stars in the outer-most regions of the Milky Way galaxy, located at a distance of 50 kpc from the
galactic centre, are observed to orbit at a speed vrot
determine the mass in the Milky Way that lies interior to 50 kpc. Express your answer in units of
the Solar mass.
250 km s-1. Using Kepler's 3rd Law,
Chapter 19 Solutions
The Cosmic Perspective (9th Edition)
Ch. 19 - Prob. 1VSCCh. 19 - Prob. 2VSCCh. 19 - Prob. 3VSCCh. 19 - Prob. 4VSCCh. 19 - Prob. 5VSCCh. 19 - Prob. 6VSCCh. 19 - Prob. 1EAPCh. 19 - Prob. 2EAPCh. 19 - Prob. 3EAPCh. 19 - Prob. 4EAP
Ch. 19 - Prob. 5EAPCh. 19 - Prob. 6EAPCh. 19 - Prob. 7EAPCh. 19 - Prob. 8EAPCh. 19 - Prob. 9EAPCh. 19 - Prob. 10EAPCh. 19 - Prob. 11EAPCh. 19 - Prob. 12EAPCh. 19 - Prob. 13EAPCh. 19 - Prob. 14EAPCh. 19 - Prob. 15EAPCh. 19 - Prob. 16EAPCh. 19 - Prob. 17EAPCh. 19 - Does It Make Sense? Decitie whether the statement...Ch. 19 - Prob. 19EAPCh. 19 - Prob. 20EAPCh. 19 - Prob. 21EAPCh. 19 - Prob. 22EAPCh. 19 - Prob. 23EAPCh. 19 - Prob. 24EAPCh. 19 - Prob. 25EAPCh. 19 - Prob. 26EAPCh. 19 - Prob. 27EAPCh. 19 - Prob. 28EAPCh. 19 - Prob. 29EAPCh. 19 - Prob. 30EAPCh. 19 - Choose the best answer to each of the following....Ch. 19 - Prob. 32EAPCh. 19 - Prob. 33EAPCh. 19 - Prob. 34EAPCh. 19 - Prob. 35EAPCh. 19 - Prob. 36EAPCh. 19 - Prob. 37EAPCh. 19 - Prob. 39EAPCh. 19 - Prob. 40EAPCh. 19 - Prob. 41EAPCh. 19 - Prob. 42EAPCh. 19 - Prob. 44EAPCh. 19 - Prob. 45EAPCh. 19 - Prob. 46EAPCh. 19 - Prob. 47EAPCh. 19 - Prob. 48EAPCh. 19 - Prob. 49EAPCh. 19 - Prob. 50EAPCh. 19 - Prob. 52EAPCh. 19 - Mass of the Central Black Hole. Suppose you...Ch. 19 - Prob. 54EAPCh. 19 - Prob. 55EAPCh. 19 - Prob. 56EAPCh. 19 - Prob. 57EAPCh. 19 - Prob. 58EAPCh. 19 - The Speed of Supernova Debris. The kinetic energy...
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