Everyone knows that the moon started out as a renegade fragment of the sun, a solar flare that fled that hellish furnace and congealed into a flat frozen pond suspended between the planets. But did you know that anger began as music, played too often and too loudly by drunken performers at weddings and garden parties? Or that turtles evolved from knuckles, ice from tears, and darkness from misunderstanding? As for the dominant thesis regarding the origin of love, I abstain from comment, nor will I allow myself to address the idea that dance began as a kiss, that happiness was an accidental import from Spain, that the ancient game of jump-the-fire gave rise to politics. But I will confess that I began as an astronomer—a liking for bright flashes, vast distances, unreachable things, a hand stretched always toward the furthest limit— and that my longing for you has not taken me very far from that original desire to inscribe a comet’s orbit around the walls of our city, to gently stroke the surface of the stars.