At 9,200 feet, there is 20 percent less oxygen than at sea level, enough to take all the air from my lungs after just three steps. But it didn’t stop Mike Brown and Konstantin Batygin from hastily shuffling into the lobby of Hale Pōhaku to check the weather forecast. They stared at the TV monitor, craning their necks, suitcases in one hand, fingers pointing to the screens with the other. “It’s Sunday,” Brown said, “there’s no new forecast until tomorrow. Damn.” We were at base camp on the dormant volcano Mauna Kea, on the big Island of Hawaii. The pair were here to use one of the most powerful telescopes in the world, called Subaru. Tomorrow night, December 3, marked the start of their sixth observing run and their next attempt to find the biggest missing object in our solar system, called — for the moment — Planet Nine.
The Onizuka Center for International Astronomy, located at Hale Pōhaku, looked exactly as you might imagine a Hawaiian dormitory built in the early 1980s would. Each table was covered in an azure nylon tablecloth with salt and pepper shakers. The backs of the chairs depicted scenes from around the island: Mauna Kea, palm trees, snow-capped volcanoes, sandy beaches. It was 7 p.m. when we arrived, and most everyone who lived and worked at these dorms was asleep. (In astronomers’ quarters, most people sleep during the day or wake at odd hours of the night to go to work.) The cafeteria was empty. “Oh my god, they have Pop-Tarts! They haven’t had Pop-Tarts here for ten years!” said Brown as he unwrapped the shiny foil package to put one in the toaster. This was a good sign — Pop-Tarts are the nonsuperstitious tradition of astronomical observing — and also dinner.
We would have a snack and go over the game plan for tomorrow night. Brown and Batygin sat down at one of the round tables, laptops out. Brown, a professor of planetary astronomy at the California Institute of Technology in Pasadena, felt optimistic.