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Author Question: The mass of visible matter in a galaxy can be estimated by measuring its luminosity. When this is ... (Read 83 times)

ss2343

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on: Jul 27, 2018
The mass of visible matter in a galaxy can be estimated by measuring its luminosity. When this is compared with the measured mass of the galaxy, astronomers find that ____.
 
  a. the measured mass is about ten times the estimated mass, due to the effects of the central black hole
  b. the measured mass is approximately equal to the estimated mass
 c. there is no clear relationship between the estimated and measured mass
 d. the measured mass is about ten times the estimated mass, due to the effects of dark matter
 e. the estimated mass is about ten times the measured mass, due to the effects of dark matter

Question 2

What technique often requires the use of a laser guide star?
 
  a. active optics
 b. photometry
 c. adaptive optics
 d. comparison spectrum
 e. representational color imaging


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ErinKing

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

d

Answer to Question 2

c


ss2343

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Reply #2 on: Jul 27, 2018
Thanks


ErinKing

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Reply #3 on: Jul 27, 2018
Welcome :)


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