eli5: If the sun revolves around the galaxy, why do we still see the same constellation that was discovered by the Romans (probably 1000s of years ago). surely they should have been scattered by now due to revolution of the sun combined with the revolution of the earth around with sun

Question

Thnx to all, for the answer. I had a good time discussing and clearing my doubt.

In: 179

Answer 1

Each star is moving fast by human being travel standards, but in terms of distances in the universe its EXTREMELY SLOW.

Our galaxy makes a full rotation in about 200 million years. when we’re talking ~2000 years since Roman times, the galaxy has made about 1/100,000th of a full rotation. If you took a photo of our galaxy 2000 years ago, and today, they would look near identical. Keep in mind that the stars we see are ALSO moving with the galaxy, so there really isnt a whole lot of “Scattering”