The duration of a second is defined using Caesium-133 [1], not using anything else like daytime or rotational speed. It's independent of such factors and will a

The duration of a second is defined using Caesium-133 [1], not using anything else like daytime or rotational speed. It's independent of such factors and will always be the same in a given frame of reference. No need to update those values. edit: I think it will lead to the same or more problems because everyone would have to change all time-related constants. Easier to add a second to the day constant (because the day constant is a subset of the seconds constant, but the seconds constant affects many more aspects than just the day constant). [1]: https://en.wikipedia.org/wiki/Isotopes_of_caesium#Caesium-133 https://en.wikipedia.org/wiki/Isotopes_of_caesium#Caesium-13...