Re: [LEAPSECS] ideas for new UTC rules

From: Poul-Henning Kamp <phk_at_PHK.FREEBSD.DK>
Date: Fri, 14 Apr 2006 19:39:31 +0200

In message <>, Steve Allen writes:
>On Fri 2006-04-14T09:43:45 +0200, Poul-Henning Kamp hath writ:
>> If you put a provisional table of leapseconds into your products and
>> reality turns out differently, who is liable for the discrepancies ?
>It's a good question. My immediate response is that my notions are
>also part of the
> "Full Time-Scale-Aware Lawyer Employment act of {YA}"

I don't want us to adopt anything that makes that necessary.

>> If you add 10 more leapsecond opportunities per year you will
>> decrease reliability of the provisional table, compared to if
>> there is only two opportunities per year.
>The motivation is that allowing ten more per year requires action on
>the part of all systems to upgrade anything which now believes only
>June and December (and they get ten years of notice to do so). More
>importantly, it allows the IERS to react better to any surprises in
>decadal fluctuations of LOD.

How does it allow IERS to react better if their horizon is defined
as five or ten years ?

>Paraphrasing Westly in the fireswamps of The Princess Bride
> DUT1 signals? I don't think they exist.
>Well, I don't think anyone uses them. If there are still many
>applications for DUT1 signals, most likely they are for sextant-style
>navigation. If the leap seconds are being predicted five years in
>advance then the annually published navigation almnacs can incorporate
>projections which are as good as the broadcast signals.


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.
Received on Fri Apr 14 2006 - 10:49:45 PDT

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