[LEAPSECS] What is GMT?

Michael Sokolov msokolov at ivan.Harhan.ORG
Wed Jan 4 15:44:27 EST 2012


Warner Losh <imp at bsdimp.com> wrote:


> There's a bit of an ambiguity in when that might be, since DUT1 drifts only

> approximately 300ms every 6 months, there's often two or three choices for

> dates for a leap second such that DUT1 still remains below 0.9s. Would you

> try to resolve that at all, or just use whatever published DUT1 numbers to

> reconstruct an approximation of UT1 and use that for your "GMT" base?


I would proceed by building the apparatus first, then worrying about
those things. The implementation I have in mind will be driven by the
utrdef.txt file, and I've already posted a draft spec and an example
utrdef.txt file a few months ago.

My vision is that there will be a community of people who will have an
unmet need for some form of Mean Solar Time once UTC ceases to fulfill
this need as a result of deleterious redefinition. Someone needs to
step up and create a Mean Solar Time Users mailing list to serve as a
community gathering place for all people who are faced with a
non-negotiable requirement for MST (be it legal, religious,
philosophical or simply a personal choice) and who will need *some*
way to continue satisfying this requirement in a post-UTC world. The
MST Users mailing list needs to welcome *everyone* who has a need for
MST regardless of the specific reason(s) why, and it needs to be open
to *all* possible options for satisfying this requirement, be they
leaps, rubberization or foregoing all precision timekeeping altogether
and using only sundials.

I would very much prefer for the MST Users mailing list to be created
by someone other than me, but if no one else is willing, I'll bite the
bullet and create it on one of my servers.

Back to your original question, my preference would be to leave those
decisions to the consensus of the MST Users community, but that
requires creating the mailing list first. My vision is that questions
like the one you've asked would be brought to the MST Users list for
discussion, and once consensus is reached, I as the maintainer of the
official utrdef.txt file used by the rubber duckies would merely
encode the community consensus decision in the utrdef.txt file format.

MS


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