rainbow explanation?

[stator vane]

can anyone give me a site to review the rainbow event?

i see it often whilst flying--the circle around the shadow of the airplane i am flying in downsun and on some cloud deck.

a very beautiful site indeed.

once into BRU sep 2003, late in the afternoon, on downwind vectors into 25R, sun directly behind us, i saw the situation arising and called all the cabin crew into the flight deck and if i only had a camera!!!! we flew straight into our own shadow with the rainbow circle around us head on. the full shadow of the wings and engines etc. a site of a life time!!!!

marvelous site, but i need a review as to what causes the event.

thanks in advance

[brimstone]

It's called "Glory" or the "Brocken bow". A Glory frequently accompanies the Brocken Spectre which is another optical phenomenon named after the mountain in Germany where it is well known.

The precise explanation of Glory is complex since it involves both back scattering of light and interference which together produce a series of diffraction rings.

Armed with this I'm sure Mr Google will be able to assist you further.

[B Fraser]

The optical physics are too complex (and dull) to explain in mere words however Google is indeed the best chance of finding some decent piccies. Other optical goodies to watch out for are "Sun Dogs" which are often seen from the ground when the sun's rays are refracted by ice crystals in sheets of thin cirrus producing a bright patch or even a small section of a rainbow.

(The refraction is always observed at a radial distance of 22.5 degrees from the sun)

Another cool sight is a moonbow (I kid you not) so check out http://www.sundog.clara.co.uk/rainbows/moonbow.htm

Complete halos around the moon are quite common when there is a thin even cirrus sheet and the following link gives you some idea of what such an event looks like http://www.sundog.clara.co.uk/halo/circmoon.htm

cool


:ok:

[stator vane]

after 14 years in alaska, i saw quite a few sun dogs and the northern lights. the best year was 84 i think, very bright lights then.

haven't seen the moonbow yet though.

and i did see the flash of green just as the sun set under the horizon in alaska once.

i've read "the strange properties of lights" and it is so bloody complicated but interesting to try to understand it. just studying the reflections of the EFIS panels off the side windows of the 737 at night is beyond my full comprehension.

thanks again.

[john_tullamarine]

I've put Les Cowley's site (listed earlier) in the useful URL sticky thread.

For those interested, Les would always appreciate any unusual inflight pix - his email in listed on the site homepage.

[Milt]

Rainbows

The little 'rainbows' often seen on stratus cloud tops which contain your own aircraft shadow are not as rare as the full sized rain drop rainbows under raining cloud which apparently need special met conditions and sunlight to materialise.

In a lifetime of flying I have only seen the phenomenon twice and look as hard as I could I was unable to see any pot of gold.

There was a thread going on the subject a year or so ago and some fascinating photos appeared. But I have yet to see a good photo of the full circle of the full whammy

Once seen - never forgotten.

[chiglet]

"Slightly" off thread, A high speed "boat" [Hoverspeed Cat, for example] has said Circular rainbows, due to spray and sun...very relaxing, and hypnot ic
watp,iktch

[ground effect]

Check out the link below for a great shot of a FULL circular rainbow.

http://www.mountainlight.com/gallery.aviation/aa0791pic.html

Shot was taken by the late great Galen Rowell (died in plane crash 2003?), one of the worlds foremost SLR landscape/adventure photographers. For those interested on the subject search around his site for more amazing natural light images plus lots of articles to read on photography/light etc etc.

It goes without saying that Brocken Spectres are common when you spend so much time above the clouds. Am a climber who is lucky to have seen these amazing spectres twice with my feet firmly planted on the ground!!!!:ok: