Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Question
Chapter 17, Problem 57Q
To determine
The aspect of the spectrum of a G2 star that one needs to concentrate on to find the luminosity class of the star given that some giant and supergiant stars are of the same spectral type.
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. The spectrum of Star A peaks at 700 nm. The spectrum of Star B peaks at 470 nm. We know
nothing about what stage of stellar evolution either of these stars are in. Which of the
following are true?
A. Star A has a higher luminosity than Star B.
B. Star B has a higher luminosity than Star A.
C. Star A is cooler than Star B.
D. Not enough information to comment on their luminosities.
E. B and C
F. C and D
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"51 Pegasi" is the name of the first normal star (besides the Sun) around which a planet was discovered. It is in the constellation Pegasus the horse. Its parallax is measured to be 0.064 arcsec.
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Chapter 17 Solutions
Universe: Stars And Galaxies
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