北极星与它周围的尘埃
2021年04月28日 North Star: Polaris and Surrounding Dust Image Credit & Copyright: Bray Falls Explanation: Why is Polaris called the North Star? First, Polaris is the nearest bright star toward the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to revolve around Polaris, but Polaris itself always stays in the same northerly direct...