Engineers at the University of Pennsylvania have designed a solar-powered data center that would orbit Earth on long, plant-like tethers. Traditional satellite designs often rely on motors and thrusters to keep solar panels pointed at the sun. The constant, gentle push of photons — known as solar radiation pressure — would act on the thin-film solar panels like wind on a weather vane. Bargatin argues that many current orbital data center concepts are either too small to matter or too complex to build. The Penn design aims for a middle path, using “tethers,” solar panels and optical communication links that are already well understood.