Wednesday, March 16, 2050

The Permafrost Problem

Back in the 20th century, an oil company was drilling for oil in northern Alaska. The oil company built its local headquarters the way it would have back in Texas, flat on the ground. What the oil company people had forgotten, though, was that the ground in northern Alaska is permafrost, basically frozen mud. In due course, the oil company's headquarters building heated up the permafrost it was resting on, and the permafrost melted, becoming ordinary mud. The building sank.

Establishing a research base on Pluto was like trying to set up a base in Alaska, only much worse. Most of the surface of Pluto is nitrogen ice at a temperature of 40 Kelvins or so, compounded by the fact that Pluto's atmosphere is terribly thin and impermanent. This means that the surface of Pluto will sublimate away at the slightest excuse. Building a base on Pluto was not like people from Texas trying to put up a building on Alaskan permafrost. It was more like people from the Sun trying to put up a building with a temperature of 5000 degrees Celsius on the surface of the Earth without having the rock below it melt into lava.

At first, the Agency's Proposals Division was afraid it would have to use some form of magnetic levitation, like a bullet train, to keep the base on Pluto out of contact with the surface. That would probably have been too expensive, and caused the Powers That Be to turn down the Pluto mission. Fortunately, advances in materials science have led to the development of astonishingly effective insulators. The Proposals Division finally came up with an acceptably cheap design in which the station rests on three insulated pads. The bottoms of the pads are at 40 Kelvins where they come into contact with the surface of Pluto, while the tops of the pads are at room temperature where they come into contact with the station's legs.

As an aside, I face the same problem myself whenever I venture out onto Pluto's surface. The same material insulating the station from the surface can be found in the thick-soled boots I wear over my spacesuit. I also have to wear gauntlets of the same material so I can handle samples of Plutonian surface material without having them evaporate away. If I ever found myself flat on my back on the surface, it would take less than a minute for the heat to be sucked out of my body through the uninsulated spacesuit. I'd become a permanent, frozen feature of the landscape.

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