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    Re: Leap second today
    From: Bill B
    Date: 2012 Jun 30, 17:43 -0400

    On 6/30/2012 4:52 PM, Gary LaPook wrote:
    > If, as is the normal case, you are only working your sights to the
    > precision of of one second of time, then you make no change and the NA
    > is always right to this level of precision. This change will result in a
    > change of the GHA by 0.25 minutes which is de minimus at this normal
    > level of precision. If you are a perfectionist then you have always made
    > the corrections of the tenths of a second broadcast on WWV so you will
    > just go on doing the same thing except the value you use will change
    > from the current plus 0.6 seconds to a minus 0.4 seconds. When you apply
    > these corrections properly there will be no change in the GHAs.
    I thought I might look to the GHA of Aires in the daily pages of the NA
    for confirmation that they do not add a leap second to the tables, but 1
    s is a little below its resolution.  The GHA of Aires usually toggles
    back and forth between an increase of and 0d 59!1 and  0d 59!2 change
    within a 24 hour2 over a two-day period.
    There is no indication of that pattern being broken around June 30th,
    until it reaches the difference between 0 hours July2 and 0 hours July
    4, where the difference remains 0d 59!1 for two consecutive days.  Given
    the resolution that is evidence of nothing more than rounding, so no
    help there.
    Bill B

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