[time-nuts] Javascript "Countdown to the Leapsecond" Nixie Clock

Kiwi Geoff geoff36 at gmail.com
Tue Jan 13 17:35:46 EST 2015

Hello All,

A few days ago, I mentioned that I had uncovered a 1 hour error in
Tom's (very cute) Nixie Countdown clock, by calculating the "delta"
using the MJD (Modified Julian Date).

Tom <tvb at leapsecond.com> wrote:
> So at one level we're all set. But the question still is, why did or does the
> code not work right for New Zealand time zones or maybe Seattle also.

I thought the easiest way to display this, was to replicate his method
and mine on a web page that shows all the workings in UTC.

This uncovered an amazing "time paradox" of how one can be 1 hour out
in the countdown clock but 12 hours early (at least in NZ) for the
Leap Second Event to be predicted.

Here is my "Countdown Comparison" utility here (no MJD , just Javascript):


That hopefully "should work" in your time-zone - Geoff nervously twitches ;-) !

Have a "click" and see if the little Utility makes sense where you
live in the world.

Tom's Nixie Countdown clock is found here:


Hope that helps anyone playing with Time and Dates in JavaScript - it
can be VERY tricky !

Regards, Kiwi Geoff ( Christchurch , New Zealand , UTC+13 ).

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