Sun Dogs & Moon Halos
By Bert Happel
5 Mar 2009
So Tuesday night I was driving our sons around town like crazy (leave the office and grab #2 from afterschool care, get home to pick up his guitar, drop him off at his lesson on the North side of town, zoom home to pick up #1 and take him to robotics team meeting on the South side of town, go back to pick up #2, take him home and pause for a bite to eat, go pick up #1 to return home for the night - WHEW!) when I noticed the strangest thing - a rainbow segment *in the Western sky*.
I was looking at the sun and seeing the rainbow off to it's side. For "normal" rainbows your back is to the sun. This was not normal.
This was weird. This was cool.
This caused me to pull off the road twice on the North side of town to snap some images. Those included the Main photo and the second of the other three. While on the South side of town I saw the spread rainbow seen in the first additional photo.
Yesterday I was talking about photography with someone at the office and displayed my images from JPG. She looked at these and said "You saw the Sun Dogs too!"
Sun Dogs?!? I'd never heard the phrase. I found that Sun Dogs are an atmospheric solar halo caused by refraction of light by ice crystals in the clouds ( http://en.wikipedia.org/wiki/Sun_dog ).
Wikipedia has a good description but I found better images at:
http://www.atoptics.co.uk/halo/parhelia.htm
http://www.atoptics.co.uk/halo/dogim0.htm
Reading all this made me remember an incident from seven years ago. While taking out the garbage I looked up at the full moon straight overhead. The moon shone brightly in a circular patch of pitch black. But sitting far out from the moon defining the blackness around it was a bright ring of light. It looked like a giant had used a hole punch in the hazy sky. I grabbed my Fuji MX-2900 to try and record some portion of the ring but the limitations of that camera gave images of a moon in pure black sky - no ring at all. Bummer.
Lately I've been using Photoshop Elements to digitize, restore and revive some 80-100 year old negatives (a couple dozen of which are glass) taken by my Grandfather. So I pulled up the moon ring images and began tweaking (OK, I didn't get what I wanted in 2001 but why delete the images when storing them is so easy and cheap?). Sure enough, in the only image without the moon I was able to extract a section of the glowing moon halo ring. From where I was standing there are no overhead obstructions so I am 100% positive that this is the moon halo and not an artifact. The Fuji has a maximum resolution of 1800 pixels so I did a screen capture of the edited image to be able to include it in this essay.
Researching online I found an image that closely resembles what I saw that night in December 2001:
http://www.atoptics.co.uk/halo/circmoon.htm
The biggest surprise to me in all of this was a notation that Sun and Moon halos are fairly common phenomenon. I hope to see more.
"I'm not sure I want to be perfect and finished. Talk about boredom..."
"Look at the sky," he said, and it was such a quick subject-change that I looked at the sky. There was some broken cirrus, way up high, the first bit of moonlight siilvering the edges.
"Pretty sky," I said.
"Is it a perfect sky?"
"Well, it's always a perfect sky, Don."
"Are you telling me that even though it's changing every second, the sky is always a perfect sky?"
"Gee, I'm smart. Yes! ... Perfect, and all the time changing. Yeah. I'll buy that."
from _Illusions_ by Richard Bach
4 responses
-
Litz Go gave props (5 Mar 2009):
wow, Bert, this is a great article and photo essay. my vote!
-
Susan Littlefield gave props (5 Mar 2009):
Sun Dogs? Moon Halos? Bert, not only are the images incredible, but the information you provided is terrific! That's what I love about JPG....another day, another lesson to be learned. Thank you so much for providing these wonderful photos and this terrific information. Definitely a yes vote from me!
-
Norman Caldwell gave props (6 Mar 2009):
Very informative, interesting and well documented. Thanks for sharing!
-
Bert Happel said (6 Mar 2009):
You're right Susan, the range of interests and abilities in this user community is amazing. And if what we post is not entertaining (unlike your puns which are entertaining :-) it had better be interesting or it won't be engaging.
