10 days to a working week is not long if your weekends are 5 days long :) Anyway, astronomy does use "Julian Dates" which are timezone agnostic (which means er

10 days to a working week is not long if your weekends are 5 days long :) Anyway, astronomy does use "Julian Dates" which are timezone agnostic (which means era and location agnostic), rational number time markers 0-based on the "beginning of history". The problems of seasonality and divisibility remain when you start caring about human life patterns more, as you suggest.