Nor Any Drop to Drink

After the Swedish mystic and theologian Emanuel Swedenborg had visions of celestial worlds “in the universe beyond our solar system,” he wrote of an inhabited planet with a “trough that was supplied with water by a small ditch from a lake.” That was in 1758. More than a century later, in 1880, the British writer Percy Greg described an unnamed explorer who travelled to Mars aboard the Astronaut, which he stocked with “a supply of water sufficient to last for double the period which the voyage was expected to occupy.” The prudent measure would prove unnecessary, though, as he soon encountered alien seas of “greyish blue” and advanced infrastructure that supplied “water of extraordinary purity to a population of perhaps a quarter of a million.”

In the twentieth century, Ray Bradbury imagined a planet that was more arid than Greg’s but that nonetheless had adequate fresh water...