Ancient people weren't stupid though. Sure there would be those who thought the world was ending, but we have a lot of evidence that people attempted to understand these phenomena to the best of their abilities. For example, one of the leading theories on the purpose of Stonehenge was that it was an observatory designed to predict eclipses. As for me, I'd probably start worshiping the sun after the eclipse is finished so that it wouldn't go away again, then start building Stonehenge of course hahahaha.