The Fixed Point in a Turning Sky

For thousands of years, sailors crossing the Mediterranean, the Atlantic, and the vast Pacific have looked up at night and found one star that does not move. Polaris, the North Star, holds its position while every other point of light in the heavens wheels and shifts through the darkness. The ancient Phoenicians staked their lives on it. So did the Vikings navigating to Iceland, and the escaped enslaved people following the "drinking gourd" north to freedom.…