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Old 08-July-2008, 03:15 PM
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aurora aurora is offline
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If the Sun is moving through the Universe and all the other things we are looking at are moving, we dont know what direction or speed they are moving (vector geometry without a fixed point?) and thus, what distance they are.
Direction and speed have to be computed relative to something.

Distances in space are so vast that the velocities of stars or galaxies are relatively unimportant in the calculation of distance.

Even so, you don't need to know direction and speed in order to determine distance
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