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Author Question: What factors are important when trying to classify a spiral galaxy? a. amount of dust and gas in ... (Read 39 times)

lracut11

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on: Jul 27, 2018
What factors are important when trying to classify a spiral galaxy?
 
  a. amount of dust and gas in the galaxy
  b. structure of the spiral arms
  c. size of the central region
  d. All of the other choices are important.

Question 2

Why are reflection nebulae blue in color?
 
  What will be an ideal response?


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Viet Thy

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

d

Answer to Question 2

Reflection nebulae look blue for the same reason the sky looks blue. Short wavelengths scatter more easily than long wavelengths, so blue photons are scattered. The blue color shows that the dust particles must be very small to preferentially scatter blue photons.


lracut11

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Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review

lindahyatt42

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Reply 3 on: Yesterday
Thanks for the timely response, appreciate it

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