[time-nuts] Re: Brain Burp re Noon and the Sun!

[Steve Allen]

On Thu 2023-11-23T09:54:46-0500 Bob kb8tq via time-nuts hath writ:
> Since we’re not confused enough already :) :) :).
>
> Let’s say you are *really* picky about this.

In that case we need to define the notions of "pole" and "meridian".

Since 1968 90 degrees north and south latitude are almost universally
intended to mean points in a conventional reference frame.
The actual poles wander around not at those conventional points,
and because of that the actual meridian is not the one on a map,
and the actual meridian today is different than it was a month ago.
Various observatories tasked with timekeeping were making corrections
for this starting in the 1950s.  This was UT1 vs. UT0.

Now UT1 is based on an entirely different convention that is vaguely
related to the classical pole and meridian model.

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