Sunday, March 24, 2013

What's a Parry Arc...Asked Nobody EVER!

Four minutes of sky November 26, 2011
A Parry Arc is a rare halo, an optical phenomenon which occasionally appears over a 22 degree halo together with an upper tangent arc.  On April 8, 1820 Sir William Edward Parry during one of his Arctic expeditions in search for the Northwest Passage made a drawing of this atmospheric phenomenon, hence the name.
Photo by Jane George, Huntsville, Alabama
Two months ago I had never heard of such a thing, but came across the photo of the month on The Cloud Appreciation Society website. They had a photo of this rather beautiful phenomenon that was shot of the Hurricane Sandy skies above Alabama.
The sky over our yard November 26, 2011
When I looked at the photo, it occurred to me that I had photographed something like it although in much less interesting skies. I had photographed it in November 2011, called it rainbows in the sky in my iPhoto album, and didn't think much of it. Last month I sent the photo to Les Cowley of Atmospheric Optics. He wrote me back and told me that I had indeed photographed a rare Parry Arc.

Here's the thing about the internet that I LOVE. Two months ago I had no idea what a Parry Arc was or even existed. I saw a photo that reminded me of something I had photographed over a year ago. A kind and generous-with-his-time physicist corresponds with me from the UK and confirms it. What would I have done even ten years ago with my never-ending desire to know everything? I really don't know. I guess we would have driven to the library, but I'm not sure I know how to search for something I'm not even sure exists. I think I could have done it with subject card catalogues, but imagine the work that would have been ahead of me starting out with a search on "rainbows in the sky."


  1. Lovely to see your Parry Arc photo! It is a joy that the internet is a library of astonishing dimensions, isn't it?

  2. Love it! And i love your never ending curiosity. the internet is indeed amazing.

  3. you would have had to have set up a tent in the library for all the time it would take you to research! internet technology has opened doors to learning i never imagined possible. and - look at you! you are something else, indeed, with the amazing sky captures, robin! :)

  4. Pure, unbridled curiosity is a wonderful thing to behold!

  5. There's no question that the internet has opened new worlds for us. I was in Huntsville on the day that amazing display appeared in the sky. It stopped me cold. I tried to take some pictures, and posted them back on Dec 3. I didn't get anything nearly good as the one at

    That display was a once-in-a-lifetime event, or close to it. Usually anyone who is interested in that kind of thing is happy to share with someone else who is also interested. I tried to get one of my coworkers to share my awe that day, but it didn't seem to register with him.

    Keep looking up.

  6. Truly amazing. I have never heard of that.

  7. Like you I am just thrilled with the ease we can obtain information these days. Without the Internet, that rare shot would have just been filed under "hum, that is interesting" and forgotten
    Congrats on your Parry Arc capture.

  8. How true! Great post on the wonders of the atmosphere and the wonder of the net.

  9. "What would I have done even ten years ago with my never-ending desire to know everything? " I used to have to go to the library Every Day to look up today's list of lookups, and knew as soon as I first heard of the Internet that this day was coming. The world kf knowledge available every minute from anywhere, I will live to see it!!! Now I'm just online almost all the time. Ask/answer. Wonder/find out. All but instant. Isn't living in the future grand?

  10. Okay, this kind of makes me sad. Two or three days after my cattle dog Bridget died, I saw a "rainbow" in the sky--no rain at all that day, and I didn't really notice any clouds (it definitely wasn't luminescence, which I would have recognized). I thought about the Dalai Lama talking about the rainbows that appear for no reason after the death of a bodhisattva. I figured my crazy, happy old girl had been a bodhisattva.

    Well, maybe she was. Maybe that rainbow that appeared out of nowhere for no apparent reason really was her message to me. And why not a Parry arc? Or another kinds of rainbow that hangs in the sky with no discernible cause?

    But your Parry arc is freakin' awesome! The things you see and know that every reader of your blog will go outside and look into the sky more often now, right? We will see things and share them with our friends and family. And so it grows.

  11. I will definitely look at the sky through smarter eyes. Great photograph.

  12. After a long day, I first read that as a PARTY Arc, and I kinda like that more than Parry Arc.

    But either way, it's way cool.