Monday, March 23, 2009

Anticipating and Seeing a Circumzenithal Arc

I've been chasing circumzenithal arcs for some time. This is the first plainly visible one that I anticipated based on the conditions: sun low in the sky, cirrus clouds passing overhead, and no clouds dimming the sun. The photo below was taken about 1 minute before the arc formed using the maximum field of view for my 18-55mm focal length lens and has been cropped in width.


3 comments:

kdar74 said...

I saw this rainbow looking thing in the clouds just today april 19th around 6:30 pm on the 5 north towards valencia, ca. But i didn't take a photo... my camera was dead. It was amazing.. i have never seen anything like it before in the day sky. The clouds looked like they were interfered by something- almost feather like.
There was something similar i saw back in 2002 at night where there were bright colors in the clouds but this was much BIGGER and still unexplained.

jg said...

Thanks for your comment.

If you ever get a picture of anything like what you saw, send it to the Atmospheric Optics website:

http://www.atoptics.co.uk/

Of course, I'd like to see the photo too.

I've displayed my other attempts to catch a circumzenuthal arc here:

http://www.brightstarstemeculavalley.org/pages/AestheticAndScientific.html

JG

jg said...

Oops. The link got cut off. Here they are again:
Aesthetic and Scientific Interestshttp://www.atoptics.co.uk/