Have you ever thought about the reason we can see so many colors? When you think of the color of the sun, what do you think of? I'm sure we've all drawn the sun as a big yellow circle at one point in our lives, but the sun doesn't just give off yellow light. If it did, we would see the whole world as yellow! The sun gives off a plethora of colors that makes it's way to Earth. After the light bounces off objects (trees, buildings, bodies) our eyes pick it up as color. Our eyes see the grass as green because it absorbs all colors except for green. The green light that hits it gets reflected back and out into the atmosphere where our eyes pick it up, send it to our brains and translate it as the color green.
The only reason we see the Earth the way we do is because the way the light bounces off of different objects in our lives. Light bends and moves in every direction. The sky is blue because of Rayleigh Scattering. Stop signs are red because they reflect red light. AND there are actually invisible red fish in the deep ocean. I know what you're thinking; a red fish that is invisible? But it's red!The cool thing is, red light can't penetrate the the deep waters of the ocean, so fish have evolved to be red. If there is no red light where they're at, then there is no light for them to reflect for other fish to see which makes them practically invisible!
Light is so cool! We see the world the way we see it because of the way light bounces off of different objects! This is what I find interesting.
Yes, I am a geek.