User talk:Petter Strandmark
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Hello, Petter Strandmark, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are some pages that you might find helpful:
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And don't forget, the edit summary is your friend. :) – Oleg Alexandrov (talk) 17:32, 20 January 2007 (UTC)
- Thanks, but I've been a member since 2005! --Petter 17:34, 20 January 2007 (UTC)
- You're not a member 'til you're welcomed. :) Oleg Alexandrov (talk) 18:07, 21 January 2007 (UTC)
[edit] Rayleigh Scattering
You recently edited Rayleigh Scattering to remove the phrase "and the reddening at sunset" from an image description. Did you find the phrase misleading in some way? The body of the article describes how Rayleigh scattering is responsible for red sunsets. Spiel496 (talk) 17:29, 7 February 2008 (UTC)
- From Sunset: The red hues of the sky at sunset and sunrise are caused by Mie Scattering, not Rayleigh Scattering. --Petter (talk) 01:00, 8 February 2008 (UTC)
- The Mie theory page makes no mention of a wavelength dependence. My intuition is that the light scattering off larger particles, like those in clouds, tends to be the same color as the incident light. So, while Mie scattering may explain why I see clouds, it does not seem to explain why they are being lit with red light. Is there something about the Rayleigh explanation you find lacking? Spiel496 (talk) 16:56, 8 February 2008 (UTC)
- My understanding (although I'm no expert at all :-) ):
- The fact that the sun is red during sunset is explained by Rayleigh Scattering (blue is scattered away).
- The fact that the sky is red during sunset is explained by Mie theory
- Rayleigh Scattering couldn't explain why the sky is red during sunset, because red wavelengths aren't scattered very much (
). Thus, all red light should come from the sun if only Rayleigh Scattering is considered. --Petter (talk) 18:36, 8 February 2008 (UTC)
- OK, it doesn't sound like we're in disagreement about the physics. The article was only trying to make your first point, that the sun is red because Rayleigh scattering took away the blue light. I think Mie scattering is a bit of a round-about way to explain why a cloud would glow red at sunset. I mean, it's being lit up by a red sun; what color would one expect? Spiel496 (talk) 22:08, 8 February 2008 (UTC)
- My understanding (although I'm no expert at all :-) ):
- The Mie theory page makes no mention of a wavelength dependence. My intuition is that the light scattering off larger particles, like those in clouds, tends to be the same color as the incident light. So, while Mie scattering may explain why I see clouds, it does not seem to explain why they are being lit with red light. Is there something about the Rayleigh explanation you find lacking? Spiel496 (talk) 16:56, 8 February 2008 (UTC)
