4
Korolev is the father of the Soviet rocket program, argubly its most important person, somewhat akin to von Braun in the USA. He's a designer of R7, direct predecessor of Soyuz that is still flying people to space. You know the shape when the boosters/first stage of Soyuz disconnect from the central stage? It's called Korolev's cross to this day. It's definitely named after the scientist. And anyway, russians didn't have a king, they had a tzar.