On 2011-09-21, Richard B. Gilbert <[email protected]> wrote: > On 9/21/2011 2:59 PM, John Hasler wrote: >> Richard B. Gilbert writes: >>> It's unfortunate that the earth DOES NOT rotate exactly 360 degrees in >>> exactly 24.000000000000 hours. This bit of poor design causes all >>> sorts of problems. Leap seconds are just one of the symptoms! >> >> Leapseconds are localization, like time zones, daylight saving, and >> leapyears. It's unfortunate that they are considered part of the >> timestream. > > Too bad that the movements of of the planets, moons, etc. are not better > behaved. Lacking the powers of the divine we must work around the fact > that the earth does not rotate exactly once in each twenty-four hours,
Again, that was the exact definition of the second until very recently. That we now (for the past 50 years or so) define the second in a way divorced from the rotation of the earth is what the problem is, not that the earth does not rotate in exactly 24 hours. > and the fact that its revolution around the Sun is similarly messy, > taking 365 days, six hours, and a few odd minutes and seconds which we > account for (mostly) by declaring a "leap year" every four years. Those > "odd minutes and seconds" also add up and must be accounted for every > hundred years or so. It would of course have been better if we had adopted the Dee proposal of 8 leap years every 33 years, instead of the current mishmash (every 4 years except centries except every fourth century, etc--essentially -- 97 leap years out of every 400) since it would have been more accurate and given a much smaller deviation of the calendar year from the true year (+- 1/2 day instead of +- 2 days or so) Of course everyone complains that doing arthmetic mod 33 is harder than arithmetic mod 400. _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
