February 18, 2002
The photo above shows a classic glory - an image of the jet airplane is ringed by colors of light. Glories aren't as rare as you might think. In fact, they're quite often seen by passengers as an aircraft moves between clouds and Sun - only passengers on the side of an aircraft looking away from the Sun can see them. If you have a strong light source (here it's the Sun) at your back, and you're looking into clouds or fog, then it's possible to see the shadow of the aircraft you're traveling on surrounded by a glory. This optical phenomena results from diffraction, in this case, the back-scattering of light by small droplets of water. The radius of the glory is dependent on the size of the drops - the smaller the drops, the bigger the glory.