Not a code. A call.
She typed three commands: Decode. Sequence. Repeat. 389339
On October 14, 1998, a radio telescope in Arecibo had recorded a single, anomalous blip from the direction of Proxima Centauri. The signal-to-noise ratio was so low that the automated system had flagged it as a microwave oven. But the raw timestamp, converted from sidereal seconds into a truncated integer, was . Not a code