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========== A calendar year is made of three hundred and
sixty five days -- a number that refuses tobe divide nicely, which is why we end up with
uneven months of either 30 or 31 days. Exceptfor February -- the runt of the litter -- which
only gets 28... except when it gets 29 andthen the year is 366 days long.Why does that happen? What kind of crazy universe
do we live in where some years are longerthan others?To answer this we need to know: just what
is a year?Way oversimplifying it: a year is the time
it takes Earth to make one trip around thesun. This happens to line up with the cycle
of the seasons.Now, drawing a little diagram like this showing
the Earth jauntily going around the sun iseasy to do, but accurately tracking a year
is tricky when you're on Earth becau...