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Author Question: What is proper motion? A) It is the true, not apparent, motion of a star in space. B) It is the ... (Read 38 times)

bcretired

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on: Jul 27, 2018
What is proper motion?
 
  A) It is the true, not apparent, motion of a star in space.
  B) It is the apparent shift as we go to opposite sides of our orbit every six months.
  C) It is the annual apparent motion of a star across the sky.
  D) It is the motion of a star towards or away from us, revealed by Doppler shifts.
  E) It is the orbital motion of a star around the Galaxy.

Question 2

How does Drake define a technological civilization?
 
  A) one that can get into space
  B) one that can communicate over interstellar distances
  C) one that has a written language
  D) one that can construct metal tools
  E) one that can have the intelligence not to destroy itself


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lou

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

C

Answer to Question 2

B


bcretired

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Reply 2 on: Jul 27, 2018
Wow, this really help

kalskdjl1212

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Reply 3 on: Yesterday
:D TYSM

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