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    Re: Navigation without Leap Seconds
    From: Richard M Pisko
    Date: 2008 Apr 18, 21:38 -0600

    On Fri, 18 Apr 2008 01:00:44 -0600,  wrote:
    > It would seem that most everyone here is in agreement that there would
    > be no
    > real problem for celestial navigation if leap seconds are abolished. Does
    > anyone disagree?
    Personally, I would be sorry to hear the double tick disappear from WWV.
    I have a surveying friend down in West Virginia who might rather take
    crossing lines of position than run a traverse or triangulations from a
    couple of distant monuments and build a new tower.  The traditional
    navigation procedure would take multiple sights and tenths of seconds
    timing to get a better fix than the newer consumer grade GPS; but he can
    still do that in theory.  Of course, setting up an RTK base station on a
    monument, and using professional equipment of that nature would be
    quicker, more accurate, and more expensive.  The RTK is basically
    celestial navigation by machine software and radio connections, but is too
    modern, I think.
    For a more traditional surveying problem, determining azimuths from the
    sun, it is surprising how fast that sun moves off the crosshair
    intersections (simplified by using a Roeloffs prism).  Those tenth of a
    second corrections from UTC to UT1 really are necessary for accuracy to
    the seconds of arc.  Not so for Polaris shots, but then slight tilting of
    the telescope's horizontal axis combined with the high altitude of the
    star introduces errors not eliminated by transiting the scope . . .  at
    least on the old optical theodolites I like . . . unless set with a well
    adjusted striding level.  Still not Celestial *navigation*, but at least
    not very electronic.
    I thank Geoffrey Kolbe for his comments and link in Navlist 4878; and that
    DUT1 figure of about -0.38 seconds currently.  I passed it on.
    Richard . . .
    Using Opera 9.2.4 after the "Dog" died
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