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    Navigation without Leap Seconds
    From: Frank Reed
    Date: 2008 Apr 14, 21:50 -0400

    The fascinating article which Fred Hebard linked:
     http://www.physicstoday.org/vol-59/iss-3/p10.html
    includes a detailed discussion about the problems of gravitational time
    dilation and extremely accurate clocks. That's the main topic, and it's
    great stuff.
    
    The article also mentions leap seconds and navigation:
    "Celestial navigators --that vanishing breed-- also like leap seconds. The
    Global Positioning System, however, cannot tolerate time jumps and employs a
    time scale that avoids leap seconds."
    
    So here's my question: what's the best way of doing celestial navigation if
    leap seconds are dropped from official time-keeping? I don't think it should
    be all that difficult to work around, but I'm not sure what the best
    approach would be. Assume we get to a point where the cumulative time
    difference is, let's say, 60 seconds (that shouldn't happen for decades, so
    this is just for the sake of argument). Should we treat the difference as a
    60 second clock correction before working the sights? Or should it be a 15
    minute of arc longitude correction after working the sights? Or something
    else entirely??
    
     -FER
    Celestial Navigation Weekend, June 6-8, 2008 at Mystic Seaport Museum:
    www.fer3.com/Mystic2008
    
    
    
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