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No need for this Greg.

On Jan 11, 2009, at 12:23 PM, Greg R. wrote:

>
> 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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