NASA’s Skyfall mission will test nuclear electric propulsion with the Space Reactor-1 Freedom spacecraft. Launching in 2028, it will deploy helicopter swarms on Mars to scout landing sites and search for water, potentially cutting travel time by 25%.​NASA’s Skyfall mission will test nuclear electric propulsion with the Space Reactor-1 Freedom spacecraft. Launching in 2028, it will deploy helicopter swarms on Mars to scout landing sites and search for water, potentially cutting travel time by 25%.  ​ science