NASA wants to send a football field-sized radiator into space for its nuclear-electric Mars rocket
NASA plans to assemble a large radiator in space for nuclear-electric Mars propulsion.

NASA is developing a nuclear electric propulsion system involving the assembly in space of a massive radiator the size of a football field. Known as MARVL (Modular Assembled Radiators for Nuclear Electric Propulsion Vehicles), the project will use robots to connect radiator panels that dissipate waste heat generated by the reactor.
This innovative approach solves the challenge of fitting the large radiator into rocket constraints by sending it in parts for robotic assembly off-planet. The MARVL radiator will use liquid metal coolants like a sodium-potassium alloy, capitalizing on NASA's expertise in robotics to address significant technological challenges.
NASA's venture will influence spacecraft design by considering in-space assembly, promoting new possibilities for nuclear propulsion vehicles. Although full-scale nuclear spacecraft remain a distant vision, MARVL represents a step toward realizing key elements of this technology.