Universe
11th Edition
ISBN: 9781319039448
Author: Robert Geller, Roger Freedman, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 21, Problem 11Q
(a)
To determine
The year in which an observer on Earth saw the nebula formed from supernova explosion, assuming constant expansion rate of Crab Nebula. It is given that the apparent size of Crab Nebula is about 5 arcmin and its size increases at the rate of 0.23 arsec per year.
(b)
To determine
Whether the answer calculated in part (a) agrees with the known year of the supernova, which is, 1054 C.E. If not, explain whether it is due to any assumption made while computing the value in part (a) or due to any other physical effect of Crab Nebula.
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International Astronomical Union reported on 24 Feb 1987:
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Time left 1:45:56
A star has initially a radius of 680000000 m and a period of rotation about its axis of 33 days.
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Chapter 21 Solutions
Universe
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