Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 17, Problem 21Q
To determine
The ratio of the luminosities for the given conditions.
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You measure a star to have a parallax angle of 0.12 arc-seconds. What fraction of a degree is this?
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Chapter 17 Solutions
Universe: Stars And Galaxies
Ch. 17 - Prob. 1QCh. 17 - Prob. 2QCh. 17 - Prob. 3QCh. 17 - Prob. 4QCh. 17 - Prob. 5QCh. 17 - Prob. 6QCh. 17 - Prob. 7QCh. 17 - Prob. 8QCh. 17 - Prob. 9QCh. 17 - Prob. 10Q
Ch. 17 - Prob. 11QCh. 17 - Prob. 12QCh. 17 - Prob. 13QCh. 17 - Prob. 14QCh. 17 - Prob. 15QCh. 17 - Prob. 16QCh. 17 - Prob. 17QCh. 17 - Prob. 18QCh. 17 - Prob. 19QCh. 17 - Prob. 20QCh. 17 - Prob. 21QCh. 17 - Prob. 22QCh. 17 - Prob. 23QCh. 17 - Prob. 24QCh. 17 - Prob. 25QCh. 17 - Prob. 26QCh. 17 - Prob. 27QCh. 17 - Prob. 28QCh. 17 - Prob. 29QCh. 17 - Prob. 30QCh. 17 - Prob. 31QCh. 17 - Prob. 32QCh. 17 - Prob. 33QCh. 17 - Prob. 34QCh. 17 - Prob. 35QCh. 17 - Prob. 36QCh. 17 - Prob. 37QCh. 17 - Prob. 38QCh. 17 - Prob. 39QCh. 17 - Prob. 40QCh. 17 - Prob. 41QCh. 17 - Prob. 42QCh. 17 - Prob. 43QCh. 17 - Prob. 44QCh. 17 - Prob. 45QCh. 17 - Prob. 46QCh. 17 - Prob. 47QCh. 17 - Prob. 48QCh. 17 - Prob. 49QCh. 17 - Prob. 50QCh. 17 - Prob. 51QCh. 17 - Prob. 52QCh. 17 - Prob. 53QCh. 17 - Prob. 54QCh. 17 - Prob. 55QCh. 17 - Prob. 56QCh. 17 - Prob. 57QCh. 17 - Prob. 58QCh. 17 - Prob. 59QCh. 17 - Prob. 60QCh. 17 - Prob. 61QCh. 17 - Prob. 62QCh. 17 - Prob. 63QCh. 17 - Prob. 64QCh. 17 - Prob. 65QCh. 17 - Prob. 66QCh. 17 - Prob. 67QCh. 17 - Prob. 68QCh. 17 - Prob. 69QCh. 17 - Prob. 70QCh. 17 - Prob. 71QCh. 17 - Prob. 72QCh. 17 - Prob. 73QCh. 17 - Prob. 74QCh. 17 - Prob. 75QCh. 17 - Prob. 76QCh. 17 - Prob. 77QCh. 17 - Prob. 78QCh. 17 - Prob. 79QCh. 17 - Prob. 80Q
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- Two stars-A and B, of luminosities 0.5 and 4.5 times the observed to have the luminosity of the Sun, respectively-are same apparent brightness. Which star is more distant, and how much farther away is it than the other?arrow_forwardA brand new telescope has been named after you. It is therefore only fitting that you get to make the very first set of observations. During your first night observing, you first measure the apparent brightness and spectrum of a group of stars that appear close to each other within the telescopes field of view. From a separate set of observations 6 months later, you are able to measure each star’s parallax. Next you plot the luminosity and temperature of each star in a Hertzsprung-Russell Diagram What features below help you conclude that the group of stars is a star cluster? Explain Approximately how old do you think this star cluster is? Explain How do you expect the spectrum of the most luminous and least luminous main sequence stars in the cluster to differ? Explain why these differences occur in terms of the star’s properties and any measured absorption lines. A year after your discovery, another new star cluster has been found by the same telescope, but its distance is too far…arrow_forwardL = ( 0.0813 ) x (Rs) ^2 x 10-0.4m x Ls where L = luminosity of the desired star Rs = distance of the stars in light years m = apparent magnitude of star Ls = Luminosity of Sun = 1.00 The calculated value of Polaris' luminosity is: a. 2382 times Ls b. 6040 times Ls c. 5566 times Ls d. 2612 times Lsarrow_forward
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