Saturday, July 19, 2014

Crepuscular Rays: Where 'God' is?


I love looking at the night sky, especially when lit with stars like bright Venus or the Big Dipper and/or Litle Dipper; those are the ones I know about and are easily recognizable. I can see them quite easily where I live. And I also love looking at cloud formations and the sky during cloudless days.

One such phenomenon that I love to witness is what is known as 'crepuscular rays' that seem to radiate downwards from the sky. When I first noticed them, I used to think, "Is that where God is?"

I was delighted to discover then that crepuscular rays are also "known as 'God rays' in atmospheric optics, are rays of sunlight that appear to radiate from the point in the sky where the sun is located. These rays, which stream through gaps in clouds (particularly stratocumulus) or between other objects, are columns of sunlit air separated by darker cloud-shadowed regions. Despite seeming to converge at a point, the rays are in fact near-parallel shafts of sunlight, and their apparent convergence is a perspective effect (similar, for example, to the way that parallel railway lines seem to converge at a point in the distance). (Bolding is mine for emphasis.)

The name comes from their frequent occurrences during crepuscular hours (those around dawn and dusk), when the contrasts between light and dark are the most obvious. Crepuscular comes from the Latin word "crepusculum", meaning twilight
." (http://en.wikipedia.org/wiki/Crepuscular_rays)

Conversely, there are also anticrepuscular rays: "Anticrepuscular rays are similar to crepuscular rays, but seen opposite the sun in the sky. Anticrepuscular rays are near-parallel, but appear to converge at the antisolar point because of linear perspective.

Anticrepuscular rays are most frequently visible near sunrise or sunset. Crepuscular rays are usually much brighter than anticrepuscular rays. This is because for crepuscular rays, seen on the same side of the sky as the sun, the atmospheric light scattering and making them visible is taking place at small angles.
"

"Although anticrepuscular rays appear to converge onto a point opposite the sun, the convergence is actually an illusion. The rays are in fact (almost) parallel, and the apparent convergence is to the vanishing point at infinity." (http://en.wikipedia.org/wiki/Anticrepuscular_rays)

Forgive me for not writing much today, but I feel I need to give my hands and eyes a break, and have some fun in the sun. For some of you, it may indeed be a day of rest.

What do you love to observe about the sky? Have you noticed either of these rays before (perhaps above the clouds in an airplane)? How did they make you feel? What did you think about when you saw them?

4 comments:

  1. I have some great photographs I've clicked of this phenomenon that you've mentioned. I did not know it had a name to it. But yes its beautiful and heartening to catch the rays converging. Thanks for sharing this info.

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    1. And thank you for reading and for your comment. I'd love to see the photos as perhaps I'll use them (as mine seem to have gone). :) <3

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  2. Wow! These pictures are awesome..Never seen something like this. Thanks for that write -up..I now now what they are called :) <3

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    1. I'm glad you enjoyed the photos Parul, though I wish I took them! ;) What inspired this post was that I noticed these types of rays YEARS ago and always wondered about them. I always felt 'God' is there, like shining through the rays. ;) <3

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