Anticrepuscular Rays Over Colorado-explanantion.

[Antaletriangle]

Explanation: What's happening over the horizon? Although the scene may appear somehow supernatural, nothing more unusual is occurring than a setting Sun and some well placed clouds. Pictured above are anticrepuscular rays. To understand them, start by picturing common crepuscular rays that are seen any time that sunlight pours though scattered clouds. Now although sunlight indeed travels along straight lines, the projections of these lines onto the spherical sky are great circles. Therefore, the crepuscular rays from a setting (or rising) sun will appear to re-converge on the other side of the sky. At the anti-solar point 180 degrees around from the Sun, they are referred to as anticrepuscular rays. Pictured above is a particularly striking set of anticrepuscular rays photographed in 2001 from a moving car just outside of Boulder, Colorado, USA.

As in some UFO cases there is sometimes a more mundane explanantion-I believe that Star peeps and their craft are here /have been here well before our good selves but we sometimes need to try and understand the world around us a little more also,as some people may have translated the above image to be project bluebeam or some alien craft, myself if i'd seen this 'live' i would have been thunderstruck by it and in a little awe of it's majesty.We carry on the belief and the search but try and keep a balance also.
Courtesy:Astronomy Picture of the Day

[Fredkc]

A picture is worth 1000 words. I for saw the term Anticrepuscular and, not being any kind of weather watcher, I had to look it up. Next came a very typical, circular definition which was of no use at all:

"Anticrepuscular rays are similar to crepuscular rays, but seen opposite the sun in the sky. "

Gee, thanks.

Fortunately WikiPedia had a bit more help.
1. This picture.
2. And a great 180 deg. panorama shot on their page for such rays.