[ntp:questions] Re: no more leap seconds?

David Woolley david at djwhome.demon.co.uk
Sat Aug 13 09:01:29 UTC 2005

In article <dNSdnWvP6b-cVmffRVn-rg at comcast.com>,
Richard B. Gilbert <rgilbert88 at comcast.net> wrote:

> Let's be realistic about this.   If the first leap hour does not occur 
> for 600 years, programmers will not begin to consider the problem until 
> about 2603 AD.    Can you say "Y2K all over again"?   I saw an article 

I agree.

Moreover, a pre-requisite for introducing leap hours would be the
elimination of daylight saving time, because:

- failing to account for daylight saving time changes is also very
  common amongst programmers;

- the existence of daylight saving time is predicated on the idea that
  it is important that civil time reflect the sunrise times on a yearly
  cycle, so allowing sunrise times to sawtooth by a further hour would
  only be acceptable, if there was no real demand for daylight saving

My feeling is that you would have to limit leaps to no more than
10 minutes before ordinary people started to become aware, and even
non-astronomers might start to notice things like sun-dials not working
properly at that sort of error.

As an aside on how difficult even the concept of daylight saving time can
be to ordinary people, for short time I was on the management committee
for the blocks of flats (US: condominium) where I live.  One of the
issues that I failed to convince the other members about was that they
should not reset the dusk to dawn time switches when they changed all
the other clocks.

(The external lighting is controlled by mechanical time switches that have
cams that vary the dusk and dawn times to match those for the latitude
for which the switch is calibrated.  The also had fixed switch off times,
that would have varied in wall clock time, if the dusk to dawn part had
been allowed to work properly.  I'm close to the Greenwich meridian,
so longtitude is not an issue.)

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