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Author Topic: Why do sunbeams appear to spread out?  (Read 2223 times)

Kenneth Silva

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Why do sunbeams appear to spread out?
« on: 15/10/2011 12:30:05 »
Kenneth Silva  asked the Naked Scientists:
   
Distance of sun from Earth.

I was out, walking my dog this morning, just as the sun came up. There was a thin cloud cover, but the sun's rays were coming through. I noticed that the light rays came in a fanned pattern. If I trace the rays back to a point of origination, I determine that the sun is maybe a mile up in the sky.

Either they've been lying to us all these years as to how far away the sun is, or something else is going on here.

Why are the light rays fanned out? Shouldn't they be more parallel if the sun is 93,000,000 miles away?

Thanks.
Ken Silva
Phoenix, AZ
USA

What do you think?
« Last Edit: 15/10/2011 12:30:05 by _system »


 

Offline Soul Surfer

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Why do sunbeams appear to spread out?
« Reply #1 on: 15/10/2011 15:41:40 »
It is a perspective effect the rays are straight parallel lines but they appear to converge in the same way that railway tracks appear to converge as they recede into the distance.
 

Offline Geezer

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Why do sunbeams appear to spread out?
« Reply #2 on: 15/10/2011 16:21:59 »
I think the light has to be coming from a nearby bright spot caused by different densities in the cloud to observe that effect. The "rays" look as if they are emanating from the sun, but they are really emanating from an image of the sun projected onto something in the Earth's atmosphere.
 

Offline Bored chemist

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Why do sunbeams appear to spread out?
« Reply #3 on: 15/10/2011 16:47:38 »
 

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Why do sunbeams appear to spread out?
« Reply #3 on: 15/10/2011 16:47:38 »

 

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