Abstract: A fission based nuclear thermal propulsion rocket engine. An embodiment provides a source of fissionable material such as plutonium in a carrier fluid having neutron moderating constituents, such as hydrogen and/or carbon, therein. In various embodiments, the carrier fluid may be methane, or ethane, or a combination thereof. A neutron source is provided, such as from a neutron beam generator. By way of engine design geometry, various embodiments may provide for intersection of neutrons with the fissionable material injected by way of the carrier fluid, while in a reactor provided in the form of a reaction chamber. Impact of neutrons on fissionable material results in a nuclear fission in sub-critical mass reaction conditions in the reactor, resulting in release of heat energy to the materials within the reactor.

Abstract: A nuclear thermal propulsion rocket engine. A source of fissionable material is provided in a bed of fuel pebbles located in a reactor. A fluid having neutron moderating constituents, such as hydrogen and/or carbon, therein, is provided, which may be in the form of methane, or ethane, or a combination thereof, or may further include various isotopes of hydrogen. An external neutron source is provided using a neutron beam generator. Reactor design geometry provides containment of fissionable material, and for any byproducts of fission reactions, in the reactor during acceleration of the rocket. Impact of neutrons on fissionable material results in a nuclear fission reaction conditions in the reactor, resulting in release of heat energy to fluids provided to the reactor. The reactor is sized and shaped to contain fuel pebbles containing fissionable material, and to confine expandable fluids as they remove heat from fuel pebbles.

Abstract: A nuclear thermal propulsion rocket engine. A source of fissionable material such as plutonium is provided utilizing a carrier fluid having neutron moderating constituents, such as hydrogen and/or carbon, therein. A carrier fluid may be methane, or ethane, or a combination thereof. A neutron source is provided, such as from a neutron beam generator. Reactor design geometry provides containment of fissionable material in the reactor during acceleration. Collisions occur between neutrons and fissionable material injected by way of the carrier fluid. Impact of neutrons on fissionable material results in a nuclear fission in sub-critical mass reaction conditions in the reactor, resulting in release of heat energy to fluids provided to the reactor.