Nuclear engine IS a nuclear reactor. https://en.wikipedia.org/wiki/Nuclear_reactor https://en.wikipedia.org/wiki/Nuclear_reactor "A nuclear reactor, formerly

Nuclear engine IS a nuclear reactor. https://en.wikipedia.org/wiki/Nuclear_reactor https://en.wikipedia.org/wiki/Nuclear_reactor "A nuclear reactor, formerly known as an atomic pile, is a device used to initiate and control a self-sustained nuclear chain reaction." Nuclear engine is a device used to initate and control a self-sustained nuclear chain reaction. This is in contrast to nuclear bomb which initiates but does not control the chain reaction. Once the reaction is started nothing else can be done with it (ie. there is no control involved other than setting up initial parameters).