Why is the sky blue?

[Skat Bo]

Do any of you know why the sky is blue? I do, and I'm curious to find out how many others do aswell. Maybe you all will have a jolly debate over who is right and wrong with your guesses.

To prove that I do know, before anyone else tells me, I'll supply you with a hint:

The answer is only two words long, and both begin with the letter 'A'.

 

[Tez]

Hmm - Neither "Rayleigh" nor "scattering" begin with an A....

 

[no one in particular]

The answer is only two words long...

Well it may take you two words, but since you asked a “why” question you were not being very specific (so says Earthborn, and I will always agree with her. I am afraid of her, actually) I will answer your question with just one word: Scatter.


edit: Damn physicist!

 

[Skat Bo]

Ok, let me be more specific. What is the scientific terminology for it. Or, what does it scatter precisely. The first question requires only two words, both begining with the letter 'A', but the second will need some sentences.

 

[Tez]

Re: Re: Why is the sky blue?

Well it may take you two words, but since you asked a “why” question you were not being very specific (so says Earthborn, and I will always agree with her. I am afraid of her, actually) I will answer your question with just one word: Scatter.


edit: Damn physicist!

 

[kerfer]

Hmm - Neither "Rayleigh" nor "scattering" begin with an A....

Duh.

That's because it's not because of Rayleigh scattering.

Sheesh. What a dummy you are.

It's because of Giant Aardvarks! Giant Aardvarks eat all the other colors. They don't like blue.

(Borrow one A from Aardvark, and put it before Giant, and they both start with 'A'. I always thought Aardvark had too many A's anyway.)

(there's at least one up there somewhere)

 

[Tez]

Ok, let me be more specific. What is the scientific terminology for it. Or, what does it scatter precisely. The first question requires only two words, both begining with the letter 'A', but the second will need some sentences.

Skat Bo, I understand exactly why the sky is blue. My claim to shame is I worked in quantum optics for several years - I can, off the top of my head, derive the appropriate cross section for Rayleigh scattering as a function of frequency. And yet, in all honesty, I have no freaking idea which two words youre looking for!. Thus, either the two glasses of wine I have consumed have lowered my intelligence down to the level of your average cosmologist p MartinM) or perhaps we should be playing hangman for obscure scientific terminology...

 

[Skat Bo]

*Stares blankly at computer screen, waiting for a correct answer (Though ardvarks is close) *

 

[Skat Bo]

Hangman it is!

A********** A**********

Each word is eleven letters long.

 

[Tez]

Do we have an "S"?

 

[Skat Bo]

A***s****** A**********

One 'S'!

 

[Tez]

How about a "t"?

 

[Skat Bo]

At**s****** Att****t***



Four 'T's!

 

[LucyR]

Rayleigh scattering.

Rayleigh scattering is elastic (i.e. no frequency change in the scattered radiation) but it does result in scattering over 4pi.

The scattering efficiency is inversely proportional to the fourth power of the wavelength, so for the lowest frequencies the scattering is small, while for the highest frequencies the scattering is such that very little light reaches your eyes from points in the sky far from the sun.

Similar considerations also explain, at least in part, the predominantly red colour of sunsets.

There of course other processes involved, such as absorption and Mie scattering.

Were you thinking of atmospheric absorption?

 

[Skat Bo]

Close, very close. But the second word isn't the one I'm thinking.

 

[Tez]

Aha - I got it!!
[COLOR=f7f7f7]Atmospheric Attenuation[/COLOR]

 

[Skat Bo]

*Applause*
Bravo!

I bestow upon you the *Trumpet Fanfare* Rub on the head for luck award!!!!!

 

[LucyR]

What fun.

 

[Skat Bo]

Hey, how do you set up the avatar? It only gives me the option to pick g2 (Which doesn't work) or do someting with a URL, but I don't understand it. Can someone help me?

 

[Tez]

Hey, how do you set up the avatar? It only gives me the option to pick g2 (Which doesn't work) or do someting with a URL, but I don't understand it. Can someone help me?

Talking to the wrong person here - I could never think of an avatar, so never bothered working it out. I do know that there's some minimum number of posts you need, perhaps you haven't exceeded it...