Gas core reactor rocket

Gas core reactor rockets are a conceptual type of rocket that is propelled by the exhausted coolant of a gaseous fission reactor. The nuclear fission reactor core may be either a vapor, gas, or plasma. They may be capable of creating specific impulses of 3 000 - 5 000 s (30 to 50 kN•s/kg) and thrust which is enough for relatively fast interplanetary travel. Heat transfer to the working fluid (propellant) is by thermal radiation, mostly in the ultraviolet, given off by the fission gas at a working temperature of around 25 000°C.
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