Double Lunar Moonbow

May 19, 2015

ARCO-IRIS_NOITE_591719

Photographer: António Araújo
Summary AuthorsAntónio Araújo; Jim Foster
 
This photo shows a double rainbow observed above Terra Chã, Azores Islands, Portugal. What's odd about this bow is that it was captured at night, two days before the full Moon. It's a moonbow: a rainbow with the Moon as the light source rather than the Sun. The colors were surprisingly strong and clear on this occasion, especially considering that the Moon's light, even when full, is feeble compared to the Sun. I used a 20-second exposure on this photo, but the colors were obvious even when viewed with the naked eye. Note that the Moon was approximately 94 percent illuminated. It's behind the camera in a clear part of the sky. Photo taken December 4, 2014 at 8:41 p.m.
 
Photo details: Canon 5D Mark III camera; Canon 16-35mm lens; f/2.8; f/4; ISO 3200.