This is something you don’t see every day, a rainbow upside down.  The giant smiley face in the sky was captured in Britain and only happens under perfect conditions.  The sky must be clear and the ice crystals have to be a certain type to get this effect.

 

"It is convex to the sun and is formed by refraction in suitably-oriented ice crystals and may show vivid rainbow colouring, as in this case."

 

[via Telegraph]