" Even when we cannot see parts of the moon, they are still physically there. During a new moon, when it is completely lit from behind, it appears only as a black, starless circle in the sky. For while we sometimes cannot see the moon, it is still there as a silhouette. Which is why I get upset when a crescent moon is shown with stars visible through the middle of it! "

― , Humble Pi: A Comedy of Maths Errors