Spaceweather.com reader Chris Erikson was driving to work yesterday when he saw something strange. It was a rainy day on the Columbia River Gorge near the Oregon-Washington border, and a beautiful double rainbow arced across the sky. Suddenly, as passed the riverbank, another rainbow cut across the double 'bow. "I've never seen such a thing before," says Erikson, who snapped this picture through the front windshield:

photo Chris Erikson

This is called a "reflection rainbow."  To understand where it comes from, remember how normal rainbows form: Sunlight bounces in and out of falling raindrops. Those raindrops act like tiny prisms, spreading sunbeams into their constituent colors. Reflection rainbows form in the same way, except the source of light is not the sun; it's the reflection of the sun from a body of water. 


"The sun must have been reflecting from the Columbia River, which was only 200 feet to my left," says Erikson. "Here's a map showing where I was."

Rainbows come in a variety of forms. The reflection rainbow Erikson photographed is just one of many you can see if you are alert for the unusual. 
Bron: http://spaceweather.com/  | Gewijzigd: 30 januari 2017, 12:51 uur, door Joyce.s