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Author Question: I observe a galaxy that is 100 million light-years away: what do I see? A) the light from the ... (Read 85 times)

Charlie

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on: Jul 27, 2018
I observe a galaxy that is 100 million light-years away: what do I see?
 
  A) the light from the galaxy as it is today, but it is blueshifted
  B) the light from the galaxy as it is today, but it is redshifted
  C) the light from the galaxy as it was 100 million years ago and it it blueshifted
  D) the light from the galaxy as it was 100 million years ago and it is redshifted
  E) Nothing: the galaxy lies beyond the cosmological horizon.

Question 2

Most active galactic nuclei are powered by
 
  A) supermassive black holes.
  B) a large number of supernovae.
  C) mergers of compact objects.
  D) black hole mergers.
  E) extra-terrestrial civilizations.


karmakat49

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Reply #1 on: Jul 27, 2018
Answer to Question 1

D

Answer to Question 2

A


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