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  • Why does the Sun appear white through clouds?
    Sunlight is "white" Blue sky is due to Rayleigh scattering, where the intensity of scattered light depends on the fourth power of the frequency, then this is why the sky is blue, since blue is in the upper bound of the visible spectrum in frequency This is because the molecules in atmosphere have a size much smaller than the wavelength of light
  • Why isnt sunlight polarized? - Physics Stack Exchange
    The sunlight which does arrive from all directions, the blue sky from Rayleigh scattering, is polarized See en wikipedia org wiki Rayleigh_sky_model
  • How can sunlight be white , but pictures of the sun be orange?
    The main reason why the sun doesn't look white is due to Rayeleigh Scattering means that the blue light from the sun is scattered so it appears to be yellow or even orange when viewed through thicker atmosphere This means that when you take a photograph of the sun (through the necessary filters) from the surface of the earth it will appear yellow or even orange
  • optics - If blue light has a higher energy than red light, why does it . . .
    As E=hf=hcλ, blue light - with a smaller wavelength - should have a higher energy However, it is the case that blue light scatters the As you've said in your question, blue light has a smaller wavelength than red light Assuming you are talking about the sky, the scattering is from particles much smaller than the wavelength of light
  • optics - Why does the sky look black in pictures taken from the summit . . .
    In pictures taken from the summit of Mount Everest (such as this one), the colour of the sky is a very dark blue or even black in some pictures I remember from my own experiences of hiking in the Himalayas that the sky appeared to be darker blue as I climbed higher
  • Why does moonlight have a lower color temperature?
    blue sky making things on the ground look yellow in comparison (because there's no sky in this photo, and the color balance is set to the same for both photos) eye being unable to perceive colors or perceiving them wrongly (Purkinje effect) when it's dark sun or moon at horizon (because they are high in the sky for this photo)
  • Why does Sun appear white at noon? - Physics Stack Exchange
    Why "at noon?" Are you asking about the difference between the apparent color of the Sun when it is high in the sky vs its apparent color when it is low on the horizon? Or are you asking, why does it ever appear white? and did you only say "at noon" because that's the best time to observe the Sun's true color?
  • Why is the sky not purple? - Physics Stack Exchange
    The net effect is that the red and green cones are stimulated about equally by the light from the sky, while the blue is stimulated more strongly This combination accounts for the pale sky blue colour It may not be a coincidence that our vision is adjusted to see the sky as a pure hue
  • visible light - Why is the sky never green? It can be blue or orange . . .
    The sky does not skip over the green range of frequencies The sky is green Remove the scattered light from the Sun and the Moon and even the starlight, if you so wish, and you'll be left with something called airglow (check out the link, it's awesome, great pics, and nice explanation)
  • Why is the sky *uniformly* blue? - Physics Stack Exchange
    I've read a lot of answers to the questions why the sky is blue However all the answers I found contain mostly qualitative analysis: Rayleigh scattering is changing the direction of blue light, so there is more blue light coming to the eye along the line of sight than the red one However these explanations raise additional questions





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