[tz] [PATCH 1/1] Add UTC to zone tables

Guy Harris guy at alum.mit.edu
Sun Mar 13 01:17:47 UTC 2016


On Mar 12, 2016, at 5:00 PM, J William Piggott <elseifthen at gmx.com> wrote:

> Any latitude could have been chosen as the universal reference, that
> wouldn't make its geographic origin disappear.

But that means that the particular longitude chosen as the universal reference has no Deep Significance.

> What is your solution? How should the UTC _file_ be cataloged in the
> zone tables?

At the top level, not under any continent, or even under Etc.

> What coordinates should the entry have?

None.  It's not intended to be local time for a particular location.

> What CC should be used?

None.

> The answers are obvious once you recognize that UTC does have a geographic origin.

I recognize that UTC:

	http://www.itu.int/dms_pubrec/itu-r/rec/tf/R-REC-TF.460-6-200202-I!!PDF-E.pdf

happens to be a time offset from TAI by a number of seconds "to ensure approximate agreement with UT1", and that UT1 is "{the mean solar time of the prime meridian obtained from direct astronomical observation} corrected for the effects of small movements of the Earth relative to the axis of rotation (polar variation)".

I do *NOT* recognize that it is a form of European time, and therefore should have the continent of Europe associated with it; for one thing, the prime meridian cuts through Africa as well.




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