Long vs Short light wavelength absorption

AI Thread Summary
Shorter wavelengths of light are more significantly affected by dust clouds than longer wavelengths, leading to a reddening effect for stars behind such clouds. This phenomenon occurs because shorter wavelengths have higher energy and experience more collisions with dust particles. The discussion references an analogy comparing light wavelengths to ripples on a pond, where larger ripples pass undisturbed while smaller ones get distorted. The concept is further explained in the referenced astrophysics book, highlighting the environmental impact on light absorption and scattering. This information is valuable for understanding light behavior in astrophysical contexts.
jumphigh
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Hi all

I was reading through an astrophysics book{1} and there I came across this sentence:

" A dust cloud can either scatter or absorb light that passes through it. Since shorter wavelengths are affected more significantly than longer ones, a star lying behind the cloud appears reddened to an observer."

I do not understand why shorter wavelengths are affected more than longer wavelengths. I may be missing some basic relation but I can't figure it out right now.

Thanks

{1}: "An introduction to modern astrophysics", R. W. Carroll, D. A. Ostlie, page 439
 
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hmm...I think it would be sth like this:

shorter wavelength -> higher energy particles -> more collision with dust cloud particles

is that correct?
 
well i found the answer before anybody answers me, i thought i should post it for future ref

same book, page 440 explains in detail about how shorter wavelength can be greater affected by the environment than long wavelengths.

As an example, the large ripples on a pond can travel along without being disturbed by the leafs and dust grains on the surface of the pond whereas small ripples get distorted.

I hope this post will be useful for someone in future.
 
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