Column – Wondering why
Why is the sky blue? This common question is one I know how to answer, although learning the truth required that I set aside a tale I’d heard in childhood. That assertion claimed the sky’s color was a reflection of the ocean. I was skeptical. I had enough experience to have observed that blue was only one of the ocean’s many colors. I had also seen clear blue skies in Kansas, which lacks ocean access.
When I became interested in astronomy, I learned a more accurate answer. Sunlight contains all the colors of the rainbow. Wavelengths associated with individual colors behave differently in earth’s atmosphere. Blue light scatters readily, so on a clear day this is the predominant color entering a viewer’s eyes. Thus, the sky appears blue. On a steamy day, extra moisture in the air causes a greater variety of wavelengths to scatter, and the sky can appear white. When the sun sits near the horizon at dusk or dawn, its light has to travel farther through the atmosphere. By the time it reaches a viewer’s eyes, most of the blue has already been scattered, leaving oranges and reds to color the experience. If earth didn’t have an atmosphere to scatter light rays, the sky would appear black.
Don’t take my word for it. Go online and look it up. Type the query into your favorite search engine. You may need to use a bit of care if you stumble upon a fanciful blog written by someone lacking expertise. No one monitors the internet to make sure all posts are factual. But if you consider the sources of the answers you find, you’ll discover many with authority. You’ll find explanations from NASA and other space agencies, weather experts including the National Oceanic and Atmospheric Administration, physics departments of several universities, respected homework sites, encyclopedias and more.
Another question I’ve been pondering is this: Why do worms crawl out onto the sidewalk when it rains? The notion that worms surface to avoid drowning may involve more folklore than fact. When I searched this question, I found old and undated mentions of the drowning theory. They lacked citations. I kept looking. A discussion written in April 2019 by Matthew Miller, Director of Science Communications for The Nature Conservancy, pointed out that earthworms don’t have lungs, so they can’t drown in the conventional sense. Worms breathe through their skin, a process that requires moisture. Miller summarized current research regarding several theories. He provided links to it. I had no reason to be suspicious of Miller, but I know it is easy to make fake documents. So instead of just clicking, I conducted my own searches for the supporting material. I took another step to verify the credentials and affiliations of the researchers he cited. Miller’s conclusion seems well supported. The most likely reason some worms surface during rainstorms is to migrate. Worms seeking mates or new territory can cover longer distances above ground when it is wet out because they require wetness to breathe.
Another question that’s been on my mind lately proved harder to answer with confidence. Why do dumplings float when they’re done? A cooking subsection of StackExchange, a website for questions and answers, offered this explanation: Two factors occur simultaneously. Starch molecules in the dough undergo chemical changes when the dumplings approach readiness. This facilitates a process whereby tiny air pockets in the dough fill with water vapor. The vapor is less dense than the boiling water, so the dumplings begin to float. The answer cites a decades-old book, On Food and Cooking by Harold McGee, which I did not have at hand for easy confirmation. Accepting the answer as true required reliance on StackExchange’s protocols for moderating discussions and rating the dependability of people providing answers. If something more important than idle curiosity had been at stake, that wouldn’t have been enough.
Are you wondering about the “why” of anything? Internet answers can be helpful, valuable or entertaining. They can also be wrong, hurtful or destructive. Sorting out which is which often requires a few extra keystrokes, but the effort will increase your confidence in the truthfulness of what you discover.
KAREN BELLENIR has been writing for The Farmville Herald since 2009. Her book, Happy to Be Here: A Transplant Takes Root in Farmville, Virginia features a compilation of her columns. It is available from PierPress.com. You can contact Karen at kbellenir@PierPress.com.