What is that?

Photographer Tony Everhardt captured a “super mirage” of West Sister Island. The mirage occurs because light travels in a straight line when the air is the same temperature, but it bends when there are temperature differences. Cold air is denser than warm air, so light bends more easily as it passes through it. When light bends toward colder air, objects appear higher than they actually are. This is called a superior mirage. The photo was taken from the Ottawa National Wildlife Refuge. (Photo by Tony Everhardt)