RORSAT[1] were Soviet satellites that carried radar and were powered by small nuclear reactors. The reactors provided between 2 and 6 kW of power. [1] https://

RORSAT[1] were Soviet satellites that carried radar and were powered by small nuclear reactors. The reactors provided between 2 and 6 kW of power. [1] https://en.wikipedia.org/wiki/RORSAT https://en.wikipedia.org/wiki/RORSAT