An interesting question but it's a definition not an invention
Apart from the history...
Scientific definition of a second:
"the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two
hyperfine levels of the ground state of the caesium 133 atom"
Second - Wikipedia, the free encyclopedia
The other key defining units are distance (metre) and mass (Kilogram). We get the MKS system with definitions that should apply anywhere in the Universe. But if you are in a black hole
... don't worry your dead.