The Great American Eclipse of 2017
I’m continuing the topic of the upcoming solar eclipse known as the Great American Eclipse.
The states the eclipse will traverse are, in order: Oregon, Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, North Carolina, and South Carolina. Twelve million Americans live in the eclipse band; but 200 million are within one day’s drive. For Mary and me, it’s two days, but we’re going anyway.
Did you know the sun has an atmosphere? Obviously, it is nothing like our atmosphere; but there is an area of gas extending away from the surface. There is a thin layer of low-density gas near the surface of the sun called the chromosphere. The part of the chromosphere closest to the surface of the sun is cooler; but, amazingly, the further from the sun, the hotter it gets.
And just like we have layers in our atmosphere, the sun’s atmosphere has two layers. Just past the chromosphere is the corona. It extends out from the sun a very long way, about 10% of the way to earth. It’s significantly hotter than the chromosphere; in fact it is far hotter than the surface of the sun itself! I know, you’d think it would have to be cooler, since it’s millions of miles away from the sun and all that. Trust me, the explanation won’t fit in this blog post.
We cannot see the sun’s atmosphere, not the chromosphere nor the corona. Even though they are hotter than the sun, we still can’t see them. At least, not with the naked eye. The reason is density. The atoms may be hotter but there are not many of them. So, the density of the sun’s atoms outshines the relatively scarce atoms in its atmosphere. Think of a tree full of green leaves with just three dark green leaves. You’re not going to see those few dark leaves amid all those other leaves.
During the total solar eclipse today, those of us in the eclipse band will get to see the sun’s atmosphere with our naked eyes. For two whole minutes, the light from the surface of the sun will be blocked, allowing us to see the less bright atmosphere around the sun. Cool! (Well, not really cool. The sun’s atmosphere is hotter than the sun. But you know what I mean.)
My astronomy book says the inner atmosphere, the chromosphere, will appear pink and the much larger outer atmosphere, the corona, will have a pale white glow. I’ll let you know. Silly? Sure; you have a TV. But what fun is that?
Please be sure to review my previous post on: The Total Solar Eclipse of 1919
Gene Doremus is a high energy, “all-fun-all-the-time” type of teacher. His enthusiasm on every conceivable topic is contagious. A biblical, Christ-centered worldview permeates everything he does.
Gene had a 31-year Air Force career, starting as a Cold War defender, then Operation Desert Shield/Storm, and finally Enduring Freedom and Iraqi Freedom. Most of his time was in the Munitions career field, but he finished as Professor of Aerospace Studies at California State University, San Bernardino. He retired as a Lieutenant Colonel in 2005. He has a B.A. in Political Science, an M.P.A. in Public Administration, and completed Air Command & Staff College in residence.