The Flying Dutchman
This incredible picture was taken in the Mission District of San Fransisco. Although it appears as though a ship is floating in mid-air, this is simply a radio tower on top of Twin Peaks, which overlooks the city. San Fransisco's unique topography often causes fog to obscure the view.
Fallstreak Hole
This natural phenomenon has a number of names, including a fallstreak hole, a hole-punch cloud, or a cloud hole. It is formed when water molecules are cooled but do not have anything around which they can solidiy. After a catalyst causes the molecules to freeze instantaneously, the absence of water molecules causes this hole to appear in the clouds.