A question about Sunrises


by Lifed
Tags: sunrises
Lifed
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#1
May9-12, 05:21 PM
P: 4
Hello everyone!

It's my first time here, so I hope everything is appropriate and I apologize if it isn't. I'd like to know if anybody has any information about these beams of light shown in the image below:

i46.tinypic.com/qqohvp.png

If anyone knows what they're called or what property of light they are caused by it would be incredibly useful for me, as I'm super interested. Also they're gorgeous.

Well, the image tags didn't work, but there's the link. I promise it's not spam
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Vorde
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#2
May9-12, 05:35 PM
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They aren't real beams of light, they are various manifestations of lens flare. Its the mechanism of the lens in the camera/eye that creates these false images, they aren't actually there.
Lifed
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#3
May9-12, 05:56 PM
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Aha, interesting. Even though they're artificial they're still awesome.

Since you seem to be rather knowledgeable, I have another question if you don't mind. Is there any cool physics related stuff to do with sunrises besides the typical Rayleigh scattering?

Jimmy
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#4
May9-12, 06:46 PM
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A question about Sunrises


Quote Quote by Lifed View Post
Is there any cool physics related stuff to do with sunrises besides the typical Rayleigh scattering?
Green Flash:

http://hyperphysics.phy-astr.gsu.edu...os/redsun.html

http://en.wikipedia.org/wiki/Green_flash
Lifed
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#5
May9-12, 06:58 PM
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Aw man, if I could get a picture of a green flash it would probably be the greatest moment of my life. Thanks man.
davenn
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#6
May9-12, 07:13 PM
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I was in Honolulu down on Waikiki Beach, Hawaii some years back
we were all down on the beach waiting for the green flash as the sun set over the ocean horizon.

RIGHT at the time it was going to happen this huge tanker ship sailed across the horizon right in front of the setting sun. As you can imagine there were dozens of us with cameras at the ready totally disappointed at not seeing the flash :(

maybe another time :)

Dave
davenn
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May9-12, 07:18 PM
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Quote Quote by Lifed View Post
there any cool physics related stuff to do with sunrises besides the typical Rayleigh scattering?
for sunrises and sunsets look in the opposite direction for the shadow of the horizon as it moves over the landscape.
another cool one seen from time to time are anticrepuscular rays .... have a look at the link below :)

anticrepuscular rays

they can also be good to photo

cheers
Dave
Lifed
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#8
May9-12, 08:06 PM
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Wooh! You guys rock. I have one more question, to do with Rayleigh scattering. I've noticed that in a lot of sunrise/sunset pictures some parts of the sky or clouds appear more yellow than the sunrise. Wouldn't, since all of the light is travelling the same distance to my eyes and therefore are scattered the same amount, everything I see be the same wavelength and as such the same color?
Vorde
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#9
May9-12, 08:23 PM
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The thing is you can approximate everything by saying all clouds are the same and all air is the same so it will all scatter equality, but in reality somethings are a bit different than others and will scatter differently.

To further this, the more air in between the light source and you, the more the light is going to get scattered. This is why sunsets are colorful, and it also is responsible for smaller distortions.
sophiecentaur
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May10-12, 04:50 AM
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Quote Quote by Lifed View Post
Wooh! You guys rock. I have one more question, to do with Rayleigh scattering. I've noticed that in a lot of sunrise/sunset pictures some parts of the sky or clouds appear more yellow than the sunrise. Wouldn't, since all of the light is travelling the same distance to my eyes and therefore are scattered the same amount, everything I see be the same wavelength and as such the same color?
Clouds at a different height and different distance from you can appear to be in the same direction. (Draw it out and it becomes obvious). This means that the path length of light passing through clouds which appear to be in the 'same place' can be different and subject to different amounts of scattering - hence their colours may look different.


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