The third rainbow was caused by an image of the sun
reflected from Potter's Marsh into the falling rain above.
September 26, 2010
I have a file showing Double Rainbows, which are commonplace. Today on Spaceweather.com, they featured photos and stories about triple rainbows and more. Sunlight reflected once inside raindrops produces the primary arc; sunlight reflected twice produces the secondary. But three rainbows is not the record. Atmospheric optics expert Les Cowley has documented cases of four, five and even six bows in the same scene. Check out Atmospheric Optics and Google Images
