How do they start a nuclear chain reaction in a fission reactor?
I know we need a critical mass but what I dont know is where that first little particle comes from that splits the next and the next... do they have a gun to fire particles or is it a case that if you have a critical mass the reaction stars by itself.
AND... no I am not building one to replace the solar panels because it is wet...because it is wet I ask but it is along the line of idle curiosity.. I can not find how it starts.
alex
