According to folklore, last night's full Moon was the "Snow Moon."
When it rose over Lake Superior, however, it looked more like molten lava. Thomas Spence of Tofte, MN, photographed the moonrise:
“There was great atmospheric distortion,” says Spence. “Ice piles and open water added to the fantastic scene.”
This is an ‘inferior mirage’, caused by a layer of relatively warm air just above the lake’s surface. A temperature gradient in the air–warmer near the open water and cooler above–created an upside-down image of the Moon below the actual Moon. The two images, reddened by the filtering effect of the low atmosphere, merged into a molten shape.
The mirage is also known as an ‘Etruscan vase mirage,’ so-called by Jules Verne, and an ‘omega mirage’ after its resemblance to the last letter of the Greek alphabet.