What color is the sky?

If you really think about it, the answer is perfectly clear! What color is the sky? Ask just about anyone and they will undoubtedly say, "blue." A few will take a moment and ponder if this is a trick question. They are likely to say, "sky blue." You know what is really weird about this? There is hardly a soul who hasn't experienced a night on Earth, yet no one is likely to say, "black." Hmmm. There just might be more to this question. Okay, so here's a little bit of a spoiler. Our sky is neither blue nor black. Well, actually, it's both, but neither. That makes sense, right? Sometimes for fun, when I ask this question to a group, I give my own answer. With the believable conviction of a true naturalist, I claim that the sky in my world is orange. I have found that expressing such things tends to gain one a lot of attention and, in equal parts, very little integrity. I have also found that backing it up and proving such grand assertations gains one great respect and trust. That's because the sky is not orange. And, yes, it sometimes is, sort of. Let me illustrate: Not long ago, I was traveling in a car with my wife and mother-in-law. The sun had just set behind us and the view in my rearview mirror was one of orange-tastic awe. I proclaimed the orange sky to my passengers and, well, they frankly ignored me because they tend to do that during focused shopping trips. But they also ignored me because they fully knew the sky is never orange. I persuaded them to turn and look, and it was like they had never seen such a thing as an orange sky before. They were astonished. It would, however, be my contention that they had seen it many times before, but they just didn't classify it as such. This time, I focused them on looking at something common from a different perspective, and this time they saw an orange sky. In fact, if you really watch a sunset or a sunrise, you will see the sky pass through all sorts of warm colors and a few cool ones, too. It turns out that many days start and end with the sky presenting itself in just about every color. So, what about a white sky? Well, that happens during the beginning and ending of some days, too, but it also happens in the middle of the day. Again, an illustration: Let's take a perfectly normal day where a clear sky dominates the clouds. Next time you're smiling under such sky, look to the zenith, which is straight up. Take in the blue. Now, slowly move your focus down to the horizon. What you will notice is that the sky's apparent "sky blue" is noticeably darker at the zenith than it is at the horizon. In fact, sometimes the daytime sky at the horizon can be considered more white than blue. So, "sky blue" is really a gradient of blue. This not only weakens the consideration that the sky is actually blue, as in a uniform sky-blue color, but it also begs the bigger question: Why do paint companies produce only a singular shade of sky blue? Would shades such as "zenith blue" or "horizon sky" be so unmarketable? Notice, too, that when the sky is blue, the blue seems so very far away. Could we visit it? Could we find a spot to be enveloped by it? Could we touch it? Perhaps we could capture this blue sky in a jar, and then market it and make a killing. (More about this in a moment.) Unfortunately, touching or capturing or even approaching the blue of the sky is about as possible as touching a rainbow. In fact, even when astronauts, even the faddish pseudo-astronauts (apologies to Captain James Kirk), rocket upward they never get any closer to the blue of the sky. For them, the blue of our sky is there, out in front of them, until it isn't. As they climb upward and our atmospheric gases thin with altitude, our blue sky dilutes to black. This leads to the strong assumption that our blue sky requires atmospheric gases. As it turns out, no atmospheric gas equals no sky-blue color. At this point, the creation of our sky's apparent blue color gets complicated. It is all based upon the sun backlighting our atmospheric gases, and they in turn absorb, refract, reflect and transmit the sun's visible spectrum of light. Each color of light has a different size wavelength and, by golly, blue is the only one that makes it to our eyes. (Wanna know more? Google Rayleigh Scattering.) So, does that mean that blue sky is an optical illusion? A grand prism parlor trick where all of the colors of the rainbow go left except blue, which goes right, and that is right where your eyes are. Again, like a rainbow, the color appears to be clearly there, but it is completely unapproachable -- you can head toward it, but you will never reach it. Take away the sun, and our sky is black. Pass sunlight sideways through thick angles of our atmosphere, which means it goes through much more prismatic, air -- like at sunrise and sunset -- then other colors do reach our eyes … like my orange sky! Okay, but this still isn't the answer to what color our sky is. One last illustration: As previously mentioned, wouldn't it be cool to capture our colorful sky in a jar? You can, in fact, place a part of our atmosphere in a jar -- a jar of air. Yet, no matter what angle you look at this jar of atmosphere, sky blue and all other colors of our sky fail to appear. We all would, without exception, say that the jar is clearly empty. So, again, what color is the sky? I hope now you can deduce, and see, that the answer to this question is perfectly clear.