Comets have transfixed humanity since ancient times. With their unpredictable apparitions tickling our pattern-seeking propensity, our hunger for casual correlations, our primal tendency toward equating unpredictability and randomness with evil, they came to be seen as omens of drought, famine, and bloodshed. Long after astronomy stripped them of such superstitious enchantment, they have continued to exert a pull on the popular imagination.
