One hour later (with 4 minutes), find the star again. (Hint: It will have risen somewhat, in a path similar to what the sun would do if it were located there.) Now find the Pointer Stars of the Big Dipper (See "Finding North" Exercise), or the Southern Cross, if in Southern Hemisphere. Remembering that the Pointers are 5° apart from each other (or Cross-bars 6°), estimate how far the star has moved in an hour to a precision of about 1°. Which of the following best describes the star's motion?
That complete's the exercise. We see that the stars rise and set very much like the sun and for the same reason: the earth is turning. Stars that rise in the east in the evening will set in the west about dawn. For a follow up, the next time you see the sun rising on whatever actual horizon you have, note the time if you are going to be at that location for one hour. Then estimate (without the benefit of the pointer stars) how many degrees it moves in an hour. Was it about the same as the star? If not, why not?
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