ON DAY 700, ALSO KNOWN AS A+1.335 (ONE YEAR AND 335 DAYS SINCE the destruction of the moon), the Cloud Ark, as seen from the Earth, looked like a bright bead strung on a silver chain. For the reasons that Dr. Dubois Jerome Xavier Harris had tried to articulate during his soliloquy aboard Arklet 2, back on A+1.0, it was expensive, in terms of propellant, to maintain an actual cloud or swarm of arklets around Izzy. Much cheaper and more reliable was to have them precede or follow the space station along the same orbital path, like a queue of ducklings with Mom in the middle. Once an arklet had found its place in that train, changing its position was a maneuver whose complications were a perennial source of surprise and consternation to newly arrived members of the so-called General Population.