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Author Question: A spaceship visits Alpha Centauri and returns to Earth. Alpha Centauri is 4.5 light-years from Earth ... (Read 148 times)

awywial

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on: Jul 27, 2018
A spaceship visits Alpha Centauri and returns to Earth. Alpha Centauri is 4.5 light-years from Earth (our second closest star).
 
  If the spaceship travels at one-half the speed of light for essentially all of its expedition, how long was the ship gone according to an observer on the spaceship?

Question 2

What is the minimum distance of two points on the moon that can be just resolved by the Keck 10. meter telescope in Hawaii (use a wavelength of 600. nm, lunar distance of 380. thousand Km):
 
  (a) if there were no atmosphere?
  (b) if the atmosphere limits resolution to 0.2 arc-sec?


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meganlapinski

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

7.8 years

Answer to Question 2

(a) 28. meters
(b) 0.4 Km


awywial

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Reply #2 on: Jul 27, 2018
Thanks


meganlapinski

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


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