Caption: (a) First-ever picture of a third order (tertiary) rainbow. Michael Grossmann took this image on May 15, 2011 in Kampfelbach, Germany. Two reference positions (A and B) for image orientation are indicated. (b) Processed version of image (a) after contrast expansion and unsharp masking, showing a rainbow-like pattern next to the image center, marked by the arrows. Credit: Michael Grossmann/Applied Optics.