[LEAPSECS] A leap second proposal to consider -- LSEM

Steve Allen sla at ucolick.org
Wed Nov 3 14:17:01 EDT 2010

On Wed 2010-11-03T11:06:36 -0700, Rob Seaman hath writ:

> > The key point of LSEM is that 100% of the months would have leap seconds,


> I think this is a previously undiscussed option.

I think this is unimplementatble silliness.

Look at the plot of the history of time scales

Over and over during the past century (really starting with
astronomers, with Ptolemy or even earlier) humans have found it
necessary to define and use a time scale which is as uniform as

For the sake of our operational system we should broadcast the most
uniform time scale that we are capable of producing.

For millennia the civil authorities have found it necessary to
redefine civil time in a way that suits them. Operational systems
don't like that (just ask every European whose iPhone alarm went off
an hour late this week).

Operational time is not civil time. They are two different needs,
both are valuable, and we have ways of handling the changing offsets.

The ITU-R should define broadcasts to be as uniform as possible while
making it clear that the purpose they are serving has no relation
to civil time.

Steve Allen <sla at ucolick.org> WGS-84 (GPS)
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