Quote:
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Originally Posted by JohnOwens
Quote:
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Originally Posted by IMO
Every clear night these cameras produce a timelapse movie (design interval 3m56s ... any guesses why?) of the rotation of the sky....
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Difference between a solar day, 24h even, and a sidereal day, 23h 56m 4.0905s. |
Of course, but why do we do it?
It allows us to do photometry on a star over a series of nights with the star at the same airmass and position on the image.