Good morning! Today's Science Solutions blog entry is to explain, without doing any research previously, why the sky is blue.

In short, the sky is blue because of reflecting light on the electromagnetic spectrum. If you didn't already know, light and waves come on a huge spectrum, ranked by wavelength and frequency of waves. Only a small part of that spectrum is visible to humans. Our brains register the light waves as color. There are seven primary colors of light that make up a rainbow - red, orange, yellow, green, blue, indigo, and violet. When an object appears to us as a certain color, it means that while all of the light waves are hitting it, it's only reflecting the light in the color we see. Basically, the sky is blue because it is absorbing light that we'd see as red, orange, yellow, green, indigo, or violet. It's reflecting the light that our brain tells us is blue. This principle goes for anything that you see as a certain color. For example, the construction paper I'm facing is absorbing light that isn't yellow and reflecting the yellow light into my eyes. If an object is black, it means that there is an absence of light waves hitting it and it appears dark and colorless. White light and color is the result of all of the colors in the visible light spectrum blending together to make one lighter color. 

I didn't do any research for this specifically as we were instructed not to, but it comes from what we've been learning in science the past two weeks. We're studying optics, or the study of light and color. The unit has a lot of vocabulary and "Why is the sky blue?" is actually one of them. To be more detailed, the sky reflects the blue light because of the gases in the atmosphere and the ozone layer. Other planets and satellites don't have that type of protection from the sun's radiation, so their skies would appear a different color to us if we were on them. Some planets, such as Saturn, have atmospheres, but no ozone layers. Saturn's sky would look orange to us if it were ever possible to stand on it, but that's an entirely different field of science. It's interesting to me how they tend to cross over into each other.

Happy Tuesday, and welcome back to Science Solutions! Our blog assignment for today is to explain what we think the greatest scientific discovery in history was and why. Today is a four-day week as we had last week and yesterday off for spring/Easter vacation and Cesar Chavez day.

In my opinion, the greatest scientific discovery was probably Charles Darwin's theory of evolution. Even though there were important discoveries that came before it, I feel like it was fundamentally important because it provided a basis and prelude for anthropologic and historical studies. Knowing where we came from is a big element of history, and when we added science to it, more and more historical knowledge became more clear and sensical. I believe in evolution since so many things around us fit into the theory and tell us that it makes sense.

Darwin's discovery set in motion a timeline of the Earth that most people use today. If it weren't for his hard work and studying, modern geology and biology wouldn't make any sense or would be unbeknownst to people. Our psychological behavior would be more covered up and would make much less sense for anyone. Even the bodily systems and the study of anatomy fit in with Darwin's theory. So do the discoveries of other scientists in the fields of natural selection and genetic mutations. Past discoveries like the Big Bang theory also compliment Darwin's work. Together they provide a base that we can add more scientific learnings as well as human history and communications on. That's why we study them and all of the big scientific discoveries.

This is not to say that Darwin's theory could stand on its own. We know more about the theory now than Charles Darwin did at his time. We can prove it to be more true than we previously thought by using the works of other scientists like those who discovered the secret of DNA or mutations. There are fundamental things that we need to know before others and use in our studies and discoveries in order to make our knowledge layered and concise. Scientific knowledge as we know it is rather like a patchwork, and without one significant discovery, it would all make less or little sense. I don't think that there is ever enough to know and we should keep using discoveries from the past to enrich our scientific learning of the world around us.