The moons of Jupiter and Saturn hide liquid water — and possibly life — beneath kilometers of ice. But reaching them is extraordinarily difficult: surface temperatures drop to −180°C, and radiation levels exceed the lethal human dose by a factor of 50. Standard electronics simply don't survive.
Until now, spacecraft have protected their electronics inside "warm boxes" — insulated, heated enclosures that are heavy and power-hungry. For distant ocean world missions, this approach is too costly and bulky.
A team at Georgia Tech led by Professor John Cressler has developed electronics based on silicon-germanium (SiGe) transistors that require no protective enclosure at all. The physics works in their favor: at low temperatures, electrons actually move faster through SiGe transistors, not slower. Meanwhile, the device structure minimizes radiation-vulnerable oxide layers, allowing the components to withstand 5 Mrad of ionizing radiation.
The key result is a working RF communications module smaller than 10 mm² that transmits data at −180°C under continuous radiation exposure — a first-of-its-kind achievement. Systems like this could operate autonomously in ice-boring probes, underwater vehicles beneath Europa's surface, or lunar rovers traversing permanently shadowed craters without any heating system at all.