The laser did not arrive clean. It had fallen through 36,000 kilometers of heaving sky above southwestern China, and the atmosphere had done what it always does to light. The beam scattered. The signal smeared. By the time it touched the ground at Lijiang Observatory, it was no longer a tight pulse of data. It was a weak, shapeless glow spread across hundreds of meters of cold mountain air.

Most receivers would have registered only noise. This one found a one gigabit-per-second data stream buried inside the wreckage. The laser that carried it drew 2 watts, less power than a small LED bulb. From a distance equal to the planet's full circumference, the link moved data five times faster than typical Starlink speeds.