How NASA will use robots to create rocket fuel on Mars: The year is 2038

After 18 months living and working on the surface of Mars, a crew of six explorers boards a deep-space transport rocket and leaves for Earth. No humans are staying behind, but work goes on without them: Autonomous robots will keep running a mining and chemical-synthesis plant they'd started years before this first crewed mission ever set foot on the planet. The plant produces water, oxygen, and rocket fuel using local resources, and it will methodically build up all the necessary supplies for the next Mars mission, set to arrive in another two years.