Angus Macdonald

A stone thrown into water leaves ripples. A satellite orbiting Earth also leaves a trace — not on water, but in the laws of physics. Its orbit is not a frozen line: it slowly rotates, like the hand of a giant clock.

In 2034, a rocket leaves a spaceport with an unusual payload: two spheres the size of a large globe, each weighing nearly a ton. No engines, no electronics. Just a mirrored surface of hundreds of corner-cube reflectors — tiny prisms that return light exactly to where it came from. This is the future space tuning fork.