Figure 57.5: Locations of the first 20 orders of rainbows in the sky. Each order bow is dimmer and wider
than the previous one. Only the 1st and 2nd order bows are visible in Nature, but the higher-order bows may
be observed in laboratory experiments, as described in theAmateur Scientistcolumn ofScientific American,
July 1977.
Figure 57.6: First ever photograph of a third-order (tertiary) rainbow, taken in southern Germany in 2011. (a)
Original photograph. PointsAandBare reference positions for image orientation. (b) Computer-enhanced
version that shows the third-order bow. Arrows show the location of the rainbow image. The Sun is off to the
right. (Großmann, Schmidt, and Haußmann,Applied Optics, 50 , 28, F134F141 (2011).)