We are a ball of rock spinning around the sun in a galaxy that is also rotating and moving through space. How is it that we still see the same constellations as seafarers thousands of years ago considering all of this movement?
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We don’t, quite. Those stars have moved *very slightly* in our sky since ancient times, but only very slightly.
The fastest moving star – in terms of its position in the sky, not its actual speed – is [Barnard’s Star](https://en.wikipedia.org/wiki/Barnard%27s_Star). It’s too dim to see with the naked eye, but if you could see it, it’d move by about half the width of the Moon in the sky over the course of a human lifetime – enough to notice, but not much.
The fastest-moving naked eye star, [Groombridge 1830](https://en.wikipedia.org/wiki/Groombridge_1830) (which you could only barely make out under the darkest skies possible with exceptional vision) moves about half that fast. The fastest that would be reasonably visible under normal dark skies, [61 Cygni](https://en.wikipedia.org/wiki/61_Cygni), is only a third that fast (and it’s still the seventh-fastest in the sky).
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