Physics To Go is an online monthly mini-magazine and a collection of more than 1000 websites with physics images, activites, and info. You can view an archived version of our July 1, 2009 issue, Atmospheric scattering below, or click to see our September 1, 2013 issue, Two views of Earth.

Physics in Your World

HyperPhysics: Blue Sky and Rayleigh Scattering image
image credit: Kabir Bakie, Creative Commons; larger image

HyperPhysics: Blue Sky and Rayleigh Scattering

The brilliant blue color of the sky is due to scattering by molecules in the atmosphere.

- Visit HyperPhysics: Blue Sky and Rayleigh Scattering for detailed explanations about why the sky is blue and an overview of different kinds of scattering.
- See this University of California article to learn why the sky appears blue, not violet.

Login to Comment on this Item


Physics at Home

Why is the Sky Blue?

Perform a scattering experiment on your own to learn why the sky is blue during the day but reddish at sunset.


Search/Browse

From Physics Research

Why isn't the Martian sky blue like the Earth's? image
image credit: NASA JPL; image source; larger image

Why isn't the Martian sky blue like the Earth's?

The Martian sky is butterscotch, not blue like our own--the butterscotch color is produced by light scattering from dust particles blown into the atmosphere by the strong Martian winds. For more on the Martian sky, see this NASA Q & A.

(This feature was updated on July 28, 2011.)


Worth a Look

Atmospheric Optics: Rays and Shadows

See pictures and detailed explanations of atmospheric phenomena at Atmospheric Optics:  Rays and Shadows. Many of the optical effects are caused by scattering sunlight.


Recent Submissions