A PBS documentary tells me two thousand years ago in Babylon astronomers notched eighteen years of eclipse repetition in cuneiform. They’d discovered what Edmond Halley named the saros cycle— measuring time without place. To calculate path, Halley tracked the moon’s 17th-century orbit numbers, came within four minutes & twenty miles & now: we know within seconds where darkness will fall, & when—a dance of knowledge & perseverance. Saros—according to the Suda, a Byzantine measure, a Chaldean number.
