Another known cause of red shift in light is the source being in a high gravitational field. Discuss how this can be eliminated asthe source of galactic red shifts, given that the shifts are proportional to distance and not to the size of the galaxy

Another known cause of red shift in light is the source being in a high gravitational field. Discuss how this can be eliminated asthe source of galactic red shifts, given that the shifts are proportional to distance and not to the size of the galaxy

Astronomy

1st Edition

ISBN:9781938168284

Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Publisher:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Chapter28: The Evolution And Distribution Of Galaxies

Section: Chapter Questions

Problem 13E: If we see a double image of a quasar produced by a gravitational lens and can obtain a spectrum of...

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A galaxy is 30 Mpc away from us and has a recession velocity of 2000 km.s-1. What isHubble’s constant based on these values?
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Can you answer all of them from this rpoblem?
Distances to very remote galaxies are estimated based on their apparent type, which indicate the number of stars in thegalaxy, and their measured brightness. Explain how the measured brightness would vary with distance. Would there be anycorrection necessary to compensate for the red shift of the galaxy (all distant galaxies have significant red shifts)? Discusspossible causes of uncertainties in these measurements
A galaxy at redshift z has an infrared luminosity of LIR. What is the approximate star formation rate of the galaxy? Express your answer in solar masses per year, rounding to the nearest integer. Values: z = 0.3 LIR = 15.9 × 1 0 37 ×10 37 W
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