2026-10-20

How Long Light Takes to Say Goodbye

At Aldaba Station, thirty-eight light-years from home, Inés Barroso's job was to calibrate the Eye, a telescope so vast that its mirrors floated a thousand kilometers apart in the void. To tune it she needed a known object, and every technician used the same one: Earth. Inés trained it on the planet each night, and each night Earth gave back a small city of yellow lights. It was Zaragoza, her own.

It took her weeks to grasp the obvious: what she saw was not happening now. The light reaching Aldaba had left thirty-eight years ago, just as her ship departed. She had made the voyage at nearly the speed of light, asleep, and had arrived at the same moment as her own farewell. So the Eye showed her, night after night, the Earth of the day after she left, and then the day after that.

One early morning, just to see, she pushed the magnification down to a neighborhood, a street, a fourth-floor apartment with the light on. In the window stood a woman of sixty with her arm raised, waving at the sky. She didn't know which star to wave at, so she waved at all of them. Inés pressed her face to the eyepiece, laughed, cried a little, and raised her hand to answer someone who had gone thirty-eight years without being able to see her.

It became a habit. Every night at a quarter past ten, her mother appeared in the window and waved. A year of light went by, then another. Her mother turned gray, leaned on a cane, grew thinner, and kept waving. That was when Inés learned the one cruel truth of her trade: the Eye could not skip ahead. It showed her mother's life at exactly the speed it happened, not a minute faster, and one night, inevitably, the window would stay dark.

She ran the numbers. Perhaps twenty years of nights remained, and she would have to watch every one, afraid of missing the very last time her mother waved. It was Tomás, the physicist on duty, who gave her a way out as he stirred his coffee in the canteen. 'If you move away from the source, you see it more slowly. It's the Doppler effect, but for time. At six-tenths of the speed of light, each day of your mother's will last you two.'

Aldaba was a station, but it was also still a ship with its sails folded. The council objected: the fuel, the mission, the planets of the system still waiting to be cataloged. Inés signed a pledge to cover the cost from her own reserve allotment and ten years of extra shifts. One morning, without ceremony, the engines woke and the station began to draw away from Earth, facing backward, like someone walking in reverse so as not to stop looking.

Now each of her mother's nights lasts two of hers. Inés has calculated that at nine-tenths of light speed the window will light up once every five days, and at ninety-nine hundredths, once a fortnight. She will never reach the final night, because the farther she goes, the slower it arrives. Her mother waves from the fourth floor, with her cane and her patience, and Inés, no longer sure whether she is fleeing or staying, raises her hand and answers, each time a little more slowly.