Main      Site Guide    
Message Forum
Re: I just wanted to say... Rayleigh scattering!
Posted By: Wolfspirit, on host 206.47.244.94
Date: Saturday, October 23, 1999, at 20:51:38
In Reply To: Re: I just wanted to say... posted by Stephen on Saturday, October 23, 1999, at 10:59:03:

> >
> > -Morris Cecil "You know, I wonder what the exact scientific explanation is behind the weird colors that the sky gets when the sun sets. That has to be proof that God exists." Glalet
> > Sat 23 Oct A.D. 1999
>
> Hey, something I actually got out of my Astronomy 100 class I'm taking: the reason for the colors when the sun rises/sets is due to the amount of atmosphere that you look through. The reason the sky normally appears blue is that various particles in the atmosphere are of the right size that they scatter blue light. Put enough of them together, and it looks blue (this is why the air that is around us seems colorless while the air miles above seems blue: you're just looking through more of it). When the sun is rising or setting, you're looking through at it nearer the horizon and hence through a different amount of atmosphere than when it is higher in the sky. This is what gives us those stunning color displays.
>
> Ste "Hoping I was actually paying attention that day in class... sigh" phen


Of course you were :-) The only point you might want to expand on is that when the sun is nearest the horizon, the rays are traveling tangent to the viewer and, hence, through a larger distance of air. The further the sunlight has to travel through air molecules, the more likely the shorter-wave component of light (blue) is scattered out -- allowing only warmer red, orange, and yellow light to reach and delight the viewer's eyes.

Wolfspirit

Replies To This Message