Colony Ship Aurora

Navigator First Class Yuna Park was born in the starboard agricultural ring of the Aurora, sixty-two light-years from a planet she had never seen, and she had made her peace with that fact long ago. Earth was a story her grandmother told — blue skies, open water, wind that did not come from ventilation ducts. Yuna understood these things the way she understood mythology: intellectually, without the ache of personal loss.

The transmission arrived during third-shift, when the bridge crew was at minimum staffing and Yuna was running routine course corrections. It came in on a frequency the Aurora's communications array was not designed to receive — a frequency that, according to the ship's technical manuals, did not exist. The message was four words long, repeated on a loop with a precision that could only be mechanical: TURN BACK. DO NOT ARRIVE.

She should have flagged it immediately. Protocol was unambiguous on unidentified transmissions. Instead, Yuna sat alone on the bridge, watching the message cycle through its repetition, and felt for the first time in her life what her grandmother must have felt when she looked out the observation windows at the receding sun — a terrible, nauseating vertigo, as though the floor of everything she knew had simply ceased to exist.