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Tonight I grabbed my dark green down-filled jacket, unused since last winter, out of the front hall closet and went outside. Still in my pajamas, I was eventually roused from the couch after hearing so much about an ongoing meteor shower. I made sure to turn off all the house lights I thought would pollute the air with obscuring photons. It was a mixture of the end of fall and the beginning of another warm winter outside. My car still held a blanket from summer picnic outings, and it now served its purpose covering my sweatpants as I lay face-up on the driveway.

The Geminid meteor shower, with origins still not fully understood by scientists, is expected to give night gazers a wonderful show tonight and tomorrow morning. Most meteor showers are caused by icy comets that venture close enough to the Sun for their bodies to melt and break up. The pieces in turn burn up in our atmosphere and produce “shooting stars”. However, the Geminid meteor shower is hypothesized to be a “rock comet,” rather than an icy one. The process of disintegration is the same, but the but object has to get much closer to the Sun in order to scorch off the gravely debris. Though there is some evidence to suggest that a rock comet indeed produces the Geminids, no one has nailed down the true composition of 3200 Phaethon, the object in question.

Meteorites do not, contrary to a popular notion, heat up and eventually disintegrate because of friction. It’s a principle of thermodynamics that when you compress a gas the temperature increases. And temperature is really a measure of the speed of particles. Consider the following air particles in a changing volume:

As the volume decreases (e.g., compression) the particles in that volume now move about faster (relatively speaking) because they have less distance to travel. The faster the particles bounce around, the larger the temperature. In a meteor shower, a meteorite rapidly compresses the air in front of it, heating the air to such a degree that the rock and ice and metal have no choice but to yield to entropy.

***

I could see my breath in the midnight air. During my time outside, waiting the obligatory period for my vision to adjust, I only saw a handful of shooting stars. They disappear as fast as they appear: bright sparks of fire on an otherwise cold evening.

To me, they were tiny flashes of superheated air and rocky debris; a thin and fleeting stroke across the heavens. But imagine the meteorite’s perspective (if there could be such a thing). An object, probably not much larger than a small pebble, rockets into a thick atmosphere, entirely different from the ultra-rarefied infinity it crossed to get here. Hurtling into Earth’s shroud at thousands of miles per hour, the surface heats rapidly, forming something of a plasma before the cracking and scorching give way to disintegration. It’s a terribly violent process. To us its an instantaneous light show.

Even after allowing my rods and cones to adjust to the darkness, I strained my eyes incessantly, seemingly hoping for a jump in my eyes’ evolution. I didn’t see much. It’s funny, considering the relative sizes, that we can survey such a large swath of sky and still miss a direct glimpse of a meteorite. It’s funny that you strain so hard to see what should be by all accounts spectacular fireballs. Maybe I wasn’t in the right area or had too much light pollution or went out at the wrong time. Still, even a few flashes were enough to evoke the only kind of spirituality I have ever considered legitimate.

The common screed against the godless is that awe leaves us. Without a divine component, profound feelings are possible, but serve no purpose, as there is none. This is what they say. But anyone, anyone who looks up at the sky and contemplates but for a moment our place in the cosmos sees right through this fallacy. To attempt to grasp the universe in your mind’s eye is fundamentally awe-inspiring, and tonight’s meteor shower was a perfect vehicle to deliver such beauty into my night. No myths need spinning, no covenants need signing. The simplest way to unfettered wonder is, as Neil deGrasse Tyson puts it, to keep looking up.

A Geminid meteor streaks across the sky over the Mojave Desert in 2009.

You feel so small.

***

Watching a meteor shower can be frustrating. In a hyper-aware state, you mistake everything for what you are looking for. Every blinking plane or twinkle of Venus draws your attention away, only for a real shooting star to streak across your periphery. The same kind of frantic surveying propels other, less physical, human endeavors too. “Ghost hunters” take every creak in a board, every window shutter banging against aluminum siding, every gust against a drafty house, as confirmation that a spirit surrounds them. I’d like to think that focusing our ample powers of over-perception on star-gazing is a bit more noble, but not much can be said laying on a cold cement driveway in slippers.

Quirks in human perception aside, a meteor shower does for us what so many books and TV shows and information campaigns strive to: it gets us think, and more importantly to care, about our place in the universe. It immediately throws Earth into perspective. The ground beneath your feet zooms away, resizing in the mind to its true cosmic proportion.

Laying there on the pavement, my eyes rushed outward as I looked inward.

I have never heard Earth described more beautifully as when Carl Sagan did in his famous “Pale Blue Dot” video. Sagan describes us as but a “mote of dust, suspended in a sunbeam.” I love that it is that same cosmic dust, the dust of which we are all made, colliding with our home that gets us to uncover those feelings again.

Especially tonight, or if you ever have the chance to witness another meteor shower for yourself, go out, look up, and gaze wonder-filled as the universe knocks on our door.



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