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Old 12-07-2009, 01:54 PM
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Starkler (Geoff)
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Quote:
Originally Posted by g__day View Post
The maths is fairly simple. The Sun is about 8 light minutes away from Earth and about 30 arc minutes wide and the Earth rotates at 15 degrees an hour (360 degrees / 24 or 15 arc miniutes a minute if you like). So in the eight minutes it takes light from the Sun to reach the Earth the Sun's true position is actually 15 / (60 / 8) = 2 arc minutes or four Sun diameters ahead of where you see it.
2 degrees, not 2 arc minutes.

I think Bojan is right. If you consider the Sun to be fixed in position and the earth rotating in relation to it, at any given time the observer is looking directly at where it is. But wait! Is this any different to the earth being a stationary object and the Sun orbiting the earth every 24 hrs? My brain hurts.
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