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Ignoring his usual pomposity (not to mention the unnecessary verbosity and 
prolixity in this post), I take it that George agrees substantially with what 
I originally posted (at least in principle, if not necessarily with my 
particular choice of words).

So thanks for finally agreeing with me, George - if only in your usual oblique 
(and occasionally obtuse) manner. That wasn't so hard, was it?

--
GregR



--- On Sat, 1/10/09, George Huxtable  wrote:

> From: George Huxtable 
> Subject: [NavList 6976] Re: Leap seconds
> To: NavList@fer3.com
> Date: Saturday, January 10, 2009, 3:52 PM
> Referring, apparently,  to posting [6933] (with which I have
> no
> disagreement) from Gary LaPook, GregR has written-
>
>
> "George:
>
> Are you reading this? Because this is EXACTLY what I was
> referring to
> earlier (i.e. that whatever time scale we use as navigators
> is totally
> irrelevant - as long as we can correlate it to the time in
> an almanac, or
> whatever is used to obtain the date/time for a celestial
> event).
>
> I still don't know if you were being troll-ish earlier
> or honestly trying to
> contribute to the discussion, but at least I'm not the
> only one who
> understands the concept - however abstract it might be for
> some on the list
> to comprehend."
>
> =============================
>
> Coming from anyone else on this list, I would simply laugh
> off the personal
> comments in that posting, but GregR has a track record of
> repeated and
> unwarranted personal unpleasantness in some of his earlier
> contributions, so
> I am disinclined to treat such matters lightly, from him.
>
> If he can avoid getting overheated, and deal with any
> question on a straight
> factual basis, as I will do, we may be able to manage
> fruitful discussion
> between us. Otherwise, not.
>
> ============================
>
> To be honest, I'm not really sure what Greg is arguing
> about. He contends
> "that whatever time scale we use as navigators is
> totally irrelevant - as
> long as we can correlate it to the time in an almanac, or
> whatever is used
> to obtain the date/time for a celestial event"
>
> I might well agree, depending on what meaning we agree on
> for "correlate".
> If that includes adjusting for the number of leap seconds
> that would have
> occurred since the almanac was produced, which is what
> would need to happen
> if we adopted Atomic Time for our clocks, then GregR and I
> do not differ.
>
> I don't know how long in advance almanacs are
> calculated and printed, but
> let's say, for the purpose of argument, five years. So
> that means that the
> almanacs that we use today were produced in 2004. There was
> no way the
> compilers could predict, then, just how much the Earth
> would slow in the
> next 5 years. If we were to switch to Atomic Time, it would
> mean that before
> we could use any of the data in an almanac, we would need
> to discover how
> much the Earth's spin had diverged from its nominal
> rate in that interval,
> and allow for it by adjusting the reading of an accurate
> clock. That applies
> to predictions, not just of the Sun, but of any planet, and
> via GHA Aries,
> any star. Each one of us, individually, would have to work
> out our own
> correction, depending on the date of our almanac and the
> (unpredictable)
> adjustment that's called for. Instead of what happens
> now, when it's done
> automatically (within less than a second of error, anyway)
> for us all, by
> applying leap-seconds to everyone's clock.
>
> It's a matter of discussion whether Atomic Time or the
> present compromise of
> Leap-second-adjusted time is the most convenient way to
> work our clocks in
> the future. My personal opinion is that neither is, but a
> smoothly adjusted
> clock-rate, that corresponds as well as possible to the
> observed rotation of
> the Earth, would be more viable over the long run. But that
> isn't relevant
> to our present discussion.
>
> Let's take the chance, now, to clear up some loose ends
> from GregR's initial
> posting, [6805]. He had written "Besides, the almanacs
> have been on UT since
> when - mid 70s? (and thus pretty much
> "disconnected" from "sun time")."
> On
> the contrary, we have seen that almanacs are, indeed,
> closely connected with
> Sun Time, because UT is, within less than a second, by the
> operation of leap
> seconds. And I have asked him what it is that he reckons
> occurred in the
> mid-70s to change that situation, to which there has been
> no reply.
>
> George.
>
> contact George Huxtable, at  george@hux.me.uk
> or at +44 1865 820222 (from UK, 01865 820222)
> or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
>
>
>
>
>
>

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