How I Killed Pluto and Why It Had It Coming - Mike Brown [16]
Opening the blackout curtains, I was greeted with more fog and now a heavy covering of wet snow. I was informed that the snow meant that there was no chance the telescope would be working that night; the dome enclosing it was frozen shut and would require direct sunlight to get unstuck. The snow also meant that the roads up and down the mountain were impassable in my two-wheel-drive truck. Instead of a quick meal before sunset with the other astronomers so that we could all run to our different telescopes when darkness arrived, we were all stuck at the Monastery for Thanksgiving. There was no television and no Internet connection, so after dinner, the other astronomers and I built a fire and caught up on our scientific reading. I was still scouring everything I could find to help me come up with ideas of what I might do. Every time I had a thought, I would ask the others around the fireplace questions about the local telescopes and how I could use them to help with this problem or that.
“How well does the infrared camera at the Hale Telescope work?” Very well, was the answer. A general conversation would follow. We would all drift back to our reading.
“Is there a long-slit mode for the echelle spectrograph?” I would pipe out. No, was the answer, but we all speculated about how a quick modification would make one possible.
“Does anyone know anything about the new thermal imager that is coming next year?” Yes, indeed.
During the course of the evening, I covered, I thought, every combination of telescope and camera and spectrograph and instrument that was available at Palomar.
Eventually one of the other astronomers asked: “Have you ever thought about the 48-inch Schmidt Telescope?”
No. I hadn’t. In fact, I only vaguely knew where it was. Down one of those side roads I never drove down? That little dome over by the water tower, maybe?
I did know, though, that when astronomers were building the huge 200-inch Hale Telescope more than fifty years ago, they realized that having the biggest telescope in the world didn’t do you much good if you didn’t know where to point it (a dilemma with which I am quite familiar). They decided that they needed to make a detailed atlas of the entire sky—a road map for the big telescope. So they built a smaller telescope, then known simply as the 48-inch Schmidt (after the size of the mirror and the general type of telescope), just down the road. The 48-inch Schmidt took pictures of the sky night after night until finally—for the first time in history—every patch had been photographed. The resulting maps of the skies—the Palomar Observatory Sky Survey—are famous throughout the astronomical world. At one time, all astronomy libraries had a wall full of cabinets containing fourteen-inch-square prints that together made up the complete Palomar Observatory Sky Survey. Each print, when pulled out of its special protective envelope, shows an area of the sky that looks about as big as your fully outstretched hand held at arm’s length. It takes 1,200 of those prints to cover the whole sky, from Polaris, the North Star, all the way down to the Southern Cross.
As a graduate student, I had been instructed in the arcane mysteries of the correct use of the Palomar Observatory Sky Survey, which was simply called POSS by the cognoscenti. First, you go to the astronomy library and open the big cabinets; then, based on the sky coordinates of where you want to be looking, either you find the library ladder and climb to the top (if you’re looking in the far north), or you sit on the floor (for the farthest southern objects), or, if you are fortunate enough to be looking for something directly overhead, you can stand comfortably and look straight ahead. With luck, you will find that the prints are stacked in the order they are supposed to