[LEAPSECS] The definition of a day

[Peter Vince]

     There have been some strong views expressed that a "day" has to mean a
solar day, i.e. midnight-to-midnight (or midday-to-midday).  That is fine,
but we seem to be arguing about what precision that is defined to.  One
camp is arguing for a smooth atomic time that slowly drifts away from mean
solar time by minutes over a period of centuries, while the other wants us
to stick rigidly to mean solar time, inserting an extra second (no, sorry -
"resetting the clocks by a second") every so often, which currently causes
some disruption and confusion.

     You can probably guess from the tone of the above which camp I fall
in, but my problem is this: the equation of time and the analemma result in
a true solar day (midnight-to-midnight, or midday-to-midday) varying by up
to plus or minus a quarter of an hour - four times a year!  Now I could
detect that by carefully noting the times of sunrise and sunset, but it
doesn't affect me one iota as a human being.  What HAS affected me is the
disruption caused by, and please forgive the loose phraseology, the adding
of an extra second every now and then.

     Surely it would be better to allow "civil time" to run smoothly from
atomic clocks, and give ourselves a few hundred years to quietly consider
how to correct the slow drift that has reached the same order of magnitude
as the analemma effect, which we regularly ignore and/or aren't even aware
of?

Peter
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