A November Tradition
What on earth would make a sane person get up at 1:30am on a cold morning and trudge outdoors? I ask myself that question each November when the alarm goes off on the peak date of the Leonid meteor shower. As I shake off sleep, the bed has never felt so warm and cozy. I am prepared, however. My clothes are at the foot of the bed, so I can dress without turning on a light and spoiling my night vision. The coffee is ready to go, just waiting for me to hit the “On” button. I check the sky through the side door window. Two folding lounge chairs are beside the door with sleeping bags and a blanket. We carry the lounge chairs outside (if you set them out the night before they will be wet), unfold them and crawl into our sleeping bags. Warm again, we savor our coffee and watch as a bright streak of light zips over our heads. Suddenly everything seems just right. Is there anything better than this?
Meteors are caused by particles in space that are in the path of the earth as it swings through its orbit. Although these objects, called meteoroids, range in size from dust particles to large objects, most are quite small. As they slam into the earth's atmosphere most end their existence with a brief flash of light. A few make it to the surface. When they do, they are called meteorites. Wethersfield, Connecticut has the dubious distinction of being the only town known to have two houses hit by meteorites, one in 1971 and one in 1982.
About 200,000,000 years ago, it is believed that a meteorite about 1000 feet in diameter slammed into Tennessee near Erin. It penetrated to a depth of around 2000 feet below the surface and exploded with the force of a 1000 megaton bomb.[i]
Now called the Wells Creek Structure, the highly eroded crater can still be seen from the air. It shows up prominently on geologic maps of Tennessee as a small spot where the underlying layers of rock from previous geologic periods are exposed, the overlying layers having been pulverized and displaced by the cataclysmic impact.
You can see sporadic meteors on just about any clear night. Meteor showers are caused when the earth passes through a stream of particles in space. In many cases these trails of debris are left along the orbits of comets. The Leonid meteor shower, for instance, is caused by debris from comet Temple-Tuttle, discovered in 1865. Because all meteors associated with a particular shower come from the same direction, the laws of perspective make them appear to radiate from a single point in the sky, called the radiant. The same effect causes two railroad tracks to appear to converge in the distance. Meteor showers are named for their radiant. The Leonids, for instance, radiate from a point within the “sickle” of the constellation, Leo. Most showers last for a number of days and have a predicted peak at which the hourly number of meteors reaches its maximum. Bright meteors, sometimes called fireballs, can leave a trail in the upper atmosphere that can last for several minutes.
The word meteor seems a little uninspired to me. It comes from the Greek meteora (things in the sky) and in its original sense refers to any phenomenon, clouds, rainbows or whatever, that appears in the sky. Meteorology comes from the same root word. "Falling stars" and "shooting stars" convey the sense of motion, if erring in the source. According to James Mooney in his Myths of the Cherokee (1900), the Cherokee word for meteor was Atsil-Tluntutsi, meaning “fire-panther.” That word describes the event very well, I think.
I don’t remember when I saw my first meteor, but several stand out in my mind. When I was seventeen my family and I were driving home from my grandfather’s funeral in Cordele, Georgia. It was late at night and no one had said anything for miles. I was looking out the right rear window when a brilliant emerald green meteor blazed into view and disappeared over the horizon.
A few years ago we were taking photos of American Toads near Tullahoma, Tennessee. We had just gotten a nice sequence of two toads mating in a mud puddle in the middle of a jeep road. A fireball as bright as a three quarter moon arced over the trees, lighting up the field around us.
One of our best experiences occurred during the 1998 Leonid meteor shower. Just on impulse, I decided to check the sky the morning before the predicted peak of the shower was supposed to occur. As I looked out our side door window I saw a bright fireball. We decided to get dressed and go outside. What followed was one of the most amazing celestial displays I’ve seen in 30 years of watching the sky. The earth was passing through a stream of larger than normal particles that had not been predicted by anyone. We saw one fireball after another, many leaving trails in the sky that lasted for several minutes. Some went all the way across the sky and disappeared over the western horizon. We sat transfixed until dawn brightened the sky and ended the show. The following night, when the shower was predicted to peak, we saw very few fireballs. We had just been very, very fortunate.
This year’s Leonids are supposed to peak on the morning of November 19th. If it’s a clear night, we’ll definitely be outside looking up. A moon near full will cut down on the number of meteors that we’ll be able to see, but this is the last year that the possibility of a meteor storm has been predicted, with large hourly numbers possible.
What I like most about meteor watching is just getting out under the stars. There is a different feeling to the sky in the early morning hours. The world is a quieter place. The fire-panthers leap silently over our heads. Down below us, across the railroad tracks that border our field, a pair of Great Horned Owls call softly back and forth. I scoot a little farther down into my sleeping bag. It won't be long now before the eastern sky begins to lighten. I savor these last few moments and wait for dawn.
[i] Geology of the Wells Creek Structure, Tennessee, C. W. Wilson, Jr. and R. G. Stearns, 1968, Tennessee Division of Geology, Bulletin 68.