How I Killed Pluto and Why It Had It Coming - Mike Brown [14]
I had almost memorized the trail, but every twenty-nine days I was reminded that there is quite a big difference between memorization and near memorization.
Every twenty-nine days the moon became new and entirely disappeared from the sky, and I was almost lost. If by luck there were clouds that night, I might be able to get enough illumination from the reflected lights of Los Angeles, just a few miles away, to help me on my way. But on days with no moon and no clouds and only the stars and planets to light the way, I would shuffle slowly down the trail knowing that over here—somewhere—was a rock that stuck out—there!—and over here I had to reach out to feel a branch—here! It was a good thing that my skin does not react strongly to the touch of poison oak.
These days I live in a more normal suburban setting and drive my car right up to my house. I even have indoor plumbing. The moon has almost no direct effect on my day-to-day life, but still, I consciously track its phases and its location in the sky and try to show my daughter every month when it comes around full. All of this, though, is just because I like the moon and find its motions and shapes fascinating. If I get busy, I can go for weeks without really noticing where it is in the sky. Back when I lived in the cabin, though, the moon mattered, and I couldn’t help but feel its monthly absences and the dark skies and my own slow shuffling down the trail.
Contrary to the way it might sound, however, back then the moon was not my friend. The two-and-a-half-year-old daughter of one of my best friends—a girl who would, a few years later, be the flower girl at my wedding—would say, when asked about the bright object nearly full in the night sky: “That’s the moon. The moon is Mike’s nemesis.” And indeed, the moon was my nemesis, because I was looking for planets. Astronomers build telescopes in the most remote places they can find—the mountains of Chile, volcanoes in Hawaii, the plains of Antarctica, even in outer space—partially in the hope of escaping the city glare that increasingly permeates the skies. For all that effort, though, we can’t hide from the brightest light that illuminates the night skies and washes out the faintest stars: the full moon.
As a new graduate student in astronomy at Berkeley, I had never previously considered the moon to be an obstacle. It was still the world that people had walked on early in my childhood, the scene that I’d drawn picture books of, the thing I’d tried to reproduce in my muddy, rock-splattered backyard; it was not a menace to be avoided. But I soon learned the lingo: Nights when the moon was full or nearly full were called “bright time” and were to be avoided by serious astronomers looking for faint objects in the sky. Times when the quarter moon was out for half of the night were “gray time.” But the coveted nights were those when the moon was new and didn’t disturb the dark sky at all. Only on those nights—“dark time”—do astronomers have a hope of detecting the very faintest blips of light that their telescopes can possibly see. I was now looking for planets, and a distant planet would indeed be a faint blip of light that the full moon would thoroughly overwhelm. So the moon became my nemesis.
I had started looking for planets by accident. In 1997 I began working as an assistant