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Bundle: Foundations of Astronomy, Enhanced, Loose-Leaf Version, 13th + MindTap Astronomy, 2 terms (12 months) Printed Access Card
13th Edition
ISBN: 9781337214353
Author: Seeds, Michael A., Backman, Dana
Publisher: Cengage Learning
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Question
Chapter 16, Problem 12P
To determine
Orbital period of the stars in the galaxy.
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Students have asked these similar questions
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 = 250 km s−1. Using Kepler’s 3rd Law, determine the mass in the Milky Way that lies interior to 50 kpc. Express your answer in units of the Solar mass.
given:
a (distance to center of galaxy in AU) = 1,717,914,439 AU
P (suns orbital period in years) = 203,782,828.3 years
M (mass of milky way galaxy in solar masses) = 1.22 x 10^11 Msun
Question:
Assume the Milky Way Galaxy is made up entirely of stars like the Sun, i.e. on average each star has the mass of 1 MSun. Under this assumption, approximately how many stars are there in our galaxy? Express this answer in billions of stars (1 billion = 109).
Figure 2 shows the "rotation curve" of
NGC 2742. It plots the “radial velocity
(V)" (how fast material is moving
either toward or away from us) that is
measured for objects at different
distances (R = radius") from the
center of the galaxy. The center of the
galaxy is at 0 kpc (kiloparsecs) with a
speed of 9 km/sec away from us.
(These velocities have been corrected
for the observed tilt of the galaxy and
represent true orbital velocities of the
stars and gas.)
200
100
U4779
-100
As you can see, one side of the galaxy
is moving with a negative velocity
(spinning toward us), while the other
side has a positive velocity (spinning
away from us). Using Newton's
gravity equation, we will be able to
determine the gravitational mass of the
entire galaxy and how the mass varies
versus distance from the galaxy's center.
-200
-8
8
-4
Radius (kpc)
Read the following text carefully and follow the instructions:
Select five radii spaced evenly from 0-10 kpc across the galaxy. Your selections should…
Chapter 16 Solutions
Bundle: Foundations of Astronomy, Enhanced, Loose-Leaf Version, 13th + MindTap Astronomy, 2 terms (12 months) Printed Access Card
Ch. 16 - Prob. 1RQCh. 16 - Of the nearby galaxies, which is the most common...Ch. 16 - Prob. 3RQCh. 16 - My center is round, and I have no spiral arms...Ch. 16 - Prob. 5RQCh. 16 - Which are more common, barred or nonbarred spiral...Ch. 16 - Prob. 7RQCh. 16 - Prob. 8RQCh. 16 - Prob. 9RQCh. 16 - Prob. 10RQ
Ch. 16 - Prob. 11RQCh. 16 - Prob. 12RQCh. 16 - Prob. 13RQCh. 16 - Prob. 14RQCh. 16 - Prob. 15RQCh. 16 - Prob. 16RQCh. 16 - Prob. 17RQCh. 16 - Prob. 18RQCh. 16 - Prob. 19RQCh. 16 - Prob. 20RQCh. 16 - Prob. 21RQCh. 16 - What is the percentage range of galaxy diameters...Ch. 16 - What is the percentage range of galaxy masses...Ch. 16 - Prob. 24RQCh. 16 - Prob. 25RQCh. 16 - Prob. 26RQCh. 16 - Prob. 27RQCh. 16 - Prob. 28RQCh. 16 - Prob. 29RQCh. 16 - Prob. 30RQCh. 16 - Prob. 31RQCh. 16 - Prob. 32RQCh. 16 - Prob. 33RQCh. 16 - Prob. 34RQCh. 16 - Prob. 1DQCh. 16 - Prob. 2DQCh. 16 - Prob. 3DQCh. 16 - Prob. 4DQCh. 16 - Prob. 1PCh. 16 - Prob. 2PCh. 16 - Prob. 3PCh. 16 - Prob. 4PCh. 16 - Prob. 5PCh. 16 - Prob. 6PCh. 16 - Prob. 7PCh. 16 - Prob. 8PCh. 16 - Prob. 9PCh. 16 - Prob. 10PCh. 16 - Prob. 11PCh. 16 - Prob. 12PCh. 16 - Prob. 13PCh. 16 - Prob. 14PCh. 16 - Prob. 15PCh. 16 - Prob. 16PCh. 16 - Prob. 1LTLCh. 16 - Prob. 2LTLCh. 16 - Prob. 3LTLCh. 16 - Prob. 4LTLCh. 16 - Prob. 5LTLCh. 16 - Prob. 6LTL
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