Wednesday, November 20, 2013

La Luna

Note: This program first aired on November 16, 2013.

Late fall is a time of quietude, of contemplation, and of reflection. The settling that is an inevitable result of the shortening days and the withdrawal that so easily comes with the cold wind, prepares us for the introspection of the long nights of the winter ahead. Along with darkness winter brings with it cold dry air, and nothing feels as naked and stark as staring up at a winter night sky, the cold infinity of deep space brought just that much closer by the utter lack of mist or cloud or earthly dampness of any kind. We are watery beings, full of fluid and lust, water is the fundamental unit of life. It is no coincidence that our most barren landscapes, our driest ecosystems are infact cold deserts, basic physical principles assure us that cold air can hold less water vapor than warm air, and all humidity is relative to temperature. So when we turn our eyes upward in the deepest of winter nights, the utter blank of the universe is just a little bit closer, we are just a little less insulated from it. That makes winter the perfect time, not only to contemplate our infinitesimal place in the universe, but also to watch the stars and the moon, and learn their patterns, learn their secrets.

When we look to the sky night after night, some things appear with regularity, though their positions change, they change so slowly that unless we are dedicated star watchers, we may not notice the subtlety of this gradual shift. Other things appear, on casual observation, completely randomly. In this shape, in this part of the sky one night, a different shape, at a different time in a different part of the sky on another. The worst offender in this second group is of course, the moon.

The moon is the closest celestial body to the Earth, by far. It functions as Earth’s natural satellite, a body captured in orbit, stuck in place by the perfect balance between the force of Earth’s gravity working the mass of the satellite, and the satellite’s own tendency as a body in motion to stay in motion in a straight line. Cut the cord of Earth’s gravity on the moon and where does the moon go? Not flying off perpendicular to us, straight out into space, but flying off on a path that follows the tangent line of whatever instantaneous location the moon occupied the moment gravity cut out.

We take the moon for granted, shining down on us on clear nights, keeping us awake but if you look at it long enough, and with a quiet enough mind, you will remember to ask the essential questions: what is the moon? What is it made of? And where did it come from? How did it get there? The simple answer is the moon is made of us. The same stuff that makes up the corporeal parts of our being is the material of the moon. As the song says, we are stardust, and it is worth remembering that every once in a while. We’ll look at those questions in more depth next week. In the mean time, as the moon is rolling towards full, take a moment each night to watch it with a quiet mind. And listen to the questions the moon asks you.

Photo by Rob Thomas, November full moon 2013.


From the Planetary Science Research group, info about lunar geology:

Many scientists are very devoted to the moon, and fund their own institutes pursuing lunar science:

They like to chat it up at NASA, here’s the transcript of a NASA chat about the moon:

One of the driest places on Earth: