Nuclear reactor

The reactor is a core power-plant of any spaceship, providing it with both thermal and electrical power.

Both fission and fusion reactors provide heat directly, through the respective nuclear reaction. Production of the electrical power from the supplied heat is performed by turbines, magnetoplasmadynamic genrators or thermoelectric generators in small crafts.

Exhaust of a nuclear thermal rocket will cool down the reactor with every burn, and waste heat is disposed with radiators.