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xkcd #2897: Light Leap Years
(imgs.xkcd.com)
Alt text:
When Pope Gregory XIII briefly shortened the light-year in 1582, it led to navigational chaos and the loss of several Papal starships.
You'd be imprecise for civil timekeeping, but spot on for astronomy
The civil rule is it's a leap year if the year is divisible by 4, unless it is also divisible by 100 unless it is also divisible by 400
We saw the rules play out in 2000 (at least those of us over 23 saw it) which is a year divisible by 100 and by 400 so it was a leap year
Yours (and astronomy's) is Julian style "if it's divisible by 4"
I prefer the newer calendars, where there is no good mental calculation for leap years - it's a leap year when the computer says it's a leap year
I almost certainly won't be alive for it, but it's funny to think about how confused people are going to be when 2100 isn't a leap year.