Centuries hence, some unfortunate families will pass down the hereditary role of guarding nuclear waste burial sites to protect the unwary; others will become the custodians of the last libraries of the old world. Visiting pilgrims will wander those dusty stacks, marveling at Icelandic sagas and National Geographic coffee-table books, noting how printing quality dropped toward the end of the industrial era, and wondering about the terrible cataclysm implied by the historical record breaking off around 2024.

Arago’s claim that Pope Callixtus III had Halley’s comet excommunicated appears to be apocryphal, but in August 2006, the International Astronomical Union formally demoted Pluto from planet proper to dwarf planet. Even celestial bodies have less job security in the Information Age than they did under religious rule.