[LEAPSECS] UTC Redefinition Advanced

Poul-Henning Kamp phk at phk.freebsd.dk
Mon Oct 25 11:28:21 EDT 2010

In message <6F0A7636-BC9C-4617-B925-EF3849744448 at noao.edu>, Rob Seaman writes:

>Leap seconds are a means to an end. The end won't vanish when the

>leap seconds do.

But didn't that end vanish a long time ago, as in "more than 100 years" ago ?

Humans used the suns position to reckon time since times before history,
fair enough.

But only because it was the best they had.

At every turn since, where a better method have been discovered, it has
been applied instead.

In the later half of the 1800's were mass produced clockwork became
widespread, people relied on the clocks even though they were later
(se below) found to have no precise correlation to earth rotation
angle, but tended to be set to whatever the locals preferred.

With the advent of mass transportation in the shape of trains, this
was found to suck, and using the new electric telegraph, the clocks
were synchronized to whatever degree possible.

Since that point in time, the clocks have been synchronized to
whatever the proper authority stipulates, with no regards to solar
time, mean or otherwise.

Dropping leap seconds amounts to the central authority adopting the
same method of time-counting as everybody else uses, and has used
since the dawn of history: 24 hours to a day, 60 minutes to the hour,
60 seconds to the minute.

The suns position in the sky has nothing to do with this, that is
in the hands of the local(-ish) politicians who legislate your

So yes, leap seconds were an means to an end, and now that astronomers
have had a further 40 years to catch up with the mechanization of
time-reckogning, it is time to drop that hack which handicaps everybody


PS: You still have not answered my question: Why did you use UTC
when you knew it was the wrong timescale for your astronomical
applications ?

Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

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