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Thanksgiving and the Great Lights
A Perfect Balance > Thanksgiving is sadly becoming just another one of those excuses to get some time off, like Memorial Day. And like Christmas it suffers from so much busy work, from family to food to football, that the entire day can pass us by and we can completely forget to celebrate it.
But now the family is gone, the extra food is in the Tupperware, and the football is… well, that will never go away I guess. So let's have our own mini-Thanksgiving! And we'll concentrate on the cosmos - specifically the Sun and Moon - to see what there might be to be thankful for.
There of course is a poetic way to look at this dynamic duo. The greater light to rule the day and the lesser light to rule the night have been revered - sometimes as gods - for millennia. They are amazingly reliable timekeepers and season markers. And there is something about the sunrise and sunset, or the crescent Moon sinking in the west, or one rising full in the east, that has this way of drowning some of us in thanksgiving and praise.
But allow me to put on a pair of cold, clinical scientific spectacles and see if there might be even more in those celestial spheres to be thankful for.
When we look deeper into the Sun and Moon we see that they are the exact same size in the sky, a phenomenon that occurs on no other planet in the solar system. This allows for those mind-altering solar eclipses, but is a wonderful thing in its own right.
It also means they are both at just the right distance to be life-sustaining orbs and not the killers they could be. What?
We don't want the Sun to be bigger or smaller in the skies above. "Bigger" could mean several things; that it is really a larger ball of gas or it is the same size as our Sun, just closer. Both would spell doom.
A naturally bigger star would burn much faster, spew out more of the lethal wavelengths of light like ultraviolet and x-rays, and die much sooner. Nothing but bad news in that.
And if our Sun appeared bigger because it was closer - closer even just by just millions of miles - we'd be headed for a heat wave that would shut this planet down. (see Venus)
Contrariwise, we don't want our Sun smaller in the sky, as in farther away. We'd freeze. (see Mars) And a legitimately smaller star, one with a smaller radius, would not give us enough energy to live. We'd have to snuggle in closer to that fire to stay warm. But in doing that the small star would, because of the laws of physics, slow down our own rotation to a near stop. And daytimes that last dozens and dozens of hours followed by equally long nighttimes are not conducive to life.
The Sun is not too big, not too small, not too close, not too far - and I am thankful for that.
And we do not want the Moon any bigger or smaller. It was much closer and bigger in the sky when it was first formed more than 4 billion years ago. Back then our planet spun so fast that our days were about 5 hours long! Winds were breakneck. And the Moon, after its miraculous formation, must have been a terrible and awesome sight in the sky, very close and thus many times bigger.
But through the eons the Moon has been slowly moving away from us, diminishing in apparent size. During this time it has tugged on us with its own just-right gravity because of its just-right mass to slow us down to a just-right 24-hour spin.
It will continue to get farther away and smaller in the sky, and will also continue to slow us down. But longer days and nights mean more extreme temperature changes, from way above 100 degrees to well below freezing. We are here at exactly the right time.
The Moon is not too big, not too small, not too close, not too far - and I am thankful for that.
There is a lot more about those two heavenly bodies that would give us a greater appreciation of them both. Suffice it to say now that they are wonderful daily reminders of how, in spite of our attempts to ruin the place, we have truly been blessed with a wonderful home.
Posted by Mark Ritter at 2006.11.26 12:49 PM | Comments (0)
