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Joseph Leahy imaged this strange dark shape in the sky that mimicked the profile of the mountain below it. Taken from Valdez, Alaska not long after sunrise on June 5, '08. ©2008 M. Joseph Leahy, shown with permission.

The dark shape is the shadow of the mountain. But how? How can the shadow be above the mountain when sun rays always point downwards? And what is the shadow being cast upon?

The mountain shadow is cast on a thin translucent cloud layer nearer to the camera and lower than the mountain. The shadow is viewed from the underside of the layer - like watching a movie through the back of the screen. It appears larger than the mountain and above it because it is much closer to the camera. We sometimes see similar cloud shadows above the clouds casting them.     More mountain shadows.