A satellite goes dark over Europe. Solar panels knocked offline by a cyber hit or a rival’s laser. No power for critical systems. Game over for that billion-dollar asset. Latvian startup Deep Space Energy says the fix is sitting in the byproducts of existing nuclear storage right now. Their radioisotope generator, built around a radically simplified Stirling engine, turns heat from Americium-241 into electricity with five times less fuel than the old NASA-style RTGs (thermos-electric generators)