And now, for the oldest question of all time: Why is the sky blue?
Here on Virtually Rick we want to arm you with the answers so the next time a kid puts you on the spot you won’t have to be embarrassed, change the subject or buy them candy to shut them up.
Ready? So come with me, let’s get virtual!
The Sky is like Isaac Newton’s prism experiment. Actually that’s Brian May -- but anyway -- Isaac Newton’s prism experiment!
Remember that? You probably used it at school! And, at this point it’s a brilliant excuse to show you Pink Floyd’s Dark Side of the Moon album cover.
As you can see, the prism splits up the white light into a spectrum of colors (and probably your mind too if you’re listening to the album!).
Let’s start with your TV screen.
Switch it on and -- oh -- the screen is completely white!
That means a) you probably need to get it fixed but also b) the color you’re seeing is white right?
Well yes and no!
Look closer and you’ll see the pixels on the screen are actually red, green and blue -- and when all three colors in a pixel shine with the same strength it tricks our eyes into thinking we see the color white.
Genius!
Just don’t ask me to explain why orange is the new black.
But white light from the sun is made up of lots of colors. How many? Ever seen a rainbow?
Well then you know precisely! It’s seven: Red, orange, yellow, green, blue, indigo and violet.
So why are the colors of a rainbow always in the same order?
Because those colors each travel at a different wavelengths. Like different radio stations that our eyes are tuned into so our eyes and brain know precisely which color we’re seeing.
Tune to a long wavelength and you see a red color, tune them to a short wavelength and you’ll see blue or indigo or violet.
But, we can only see what’s visble not invisible. Well obvies!!
In fact if our eyes WERE more sensitive we’d see a lot more stuff on what’s called 'the electromagnetic spectrum.' But we can’t, so stop it!
So why do we see a rainbow in the first place? Raindrops!
Light moves pretty fast. You’ve heard of the 'speed of light,' right? Well turns out you can slow light down if it passes through things and it slows down as it passes through a drop of water, which bends or refracts the light, separating it out into all the colors that make up white light.
Basically . . . back to Pink Floyd again.
WOAHH MANNN COSMIC. Except WAYYYY bigger…and in the sky.
OK, that’s enough.
So why is the sky blue? Well hang on -- it’s because of our air -- the atmosphere! Which acts like a prism or the raindrops.
Simplifying this massively, white sunlight is moving fast until it hits the atmosphere and slows down. And most of the top colors of the rainbow, reds, oranges and yellows make it through mixed together as white-ish sunlight but blue and violet are just the right wavelengths to bounce off the particles of gas in the atmosphere so they get separated from the other colors (PINK FLOYD AGAIN - WOW!!! Ok stop it) and get scattered all over the place making the sky appear blue to us.
So now you know. Easy huh? Actually, perhaps it’s easier when kids do ask you tell them why the sky is blue to say that you don’t know.
I grew up in England where the sky was always grey. And please don’t ask me to explain that!