Unusual Rainbow Clouds

Discussion

4 replies

Posted by Andrew Yip on January 12, 2009 at 12:23 AM

I saw these unusual rainbow clouds (at center) just after sunset today. I've never seen anything like it before.

Posted by Aaron Ellingsen on January 12, 2009 at 2:25 AM

I've seen this a few times before. I believe it is called irisation. When cloud particles are close together and very uniform in size they refract the light just like a prizm would. It is also basically the same iridescent effect that is seen on soap bubbles.

Posted by Andrew Yip on January 12, 2009 at 11:18 AM

Neat! Thanks for the explanation Aaron.

Posted by Joseph Campisi on January 13, 2009 at 4:01 AM

Very cool phenomena, Andrew. I guess "sundog" would be the layman's term?

Posted by Andrew Yip on January 13, 2009 at 10:51 AM

Based on the other pictures I could find online, it sounds like they might be slightly different phenomena. Here are the wikipedia pages:

http://en.wikipedia.org/wiki/Sun_dog
http://en.wikipedia.org/wiki/Irisation