sci.astro.amateur
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Re: Starmapping software

Subject: Re: Starmapping software
From: "OG"
Date: Mon, 2 Oct 2006 20:43:13 +0100
Newsgroups: sci.astro.amateur
"oriel36" <geraldkelleher@xxxxxxxxx> wrote in message 
news:1159809785.851218.96500@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>
>
> Let me show you what you believe through Flamsteed's justification of
> the return of a star to a meridian -
>
> http://www.nmm.ac.uk/server/show/nav.00500300l005001000
>
> In your mind a shadow returns to noon in 24 hours exactly

What does 'a shadow returning to noon' mean? . Noon is a time, A shadow is a 
moving line on the ground. You have confused yourself once again.

> In your mind a shadow returns to noon in 24 hours exactly

Does the NMM definition of the 24 hour solar day include the word 'exactly' 
in reference to the passage of the sun across the sky? No, I didn't think so 
either.

> In your mind a shadow returns to noon in 24 hours exactly in order to
> justify the reurn of a star in 23 hours 56 minutes 04 seconds.

The sidereal day is exact. There is no need to posit an exactness to the 
solar day to determine the exactness of the sidereal day.

> I can no longer compete with such rubbish as the NMM explanation above
> when the actual principles which correlate clocks with axial rotation
> through the noon Equation of Time correction at precisely 4 minutes for
> each degree of rotation are so gorgeous that I have trouble imagining
> why anyone would intentionally destroy it

It does not 'destroy' it to point out that it is dependent on a fudge 
factor, a correction.  You know what a "correction" is?  it is something 
needed to make something else correct!

<snippage>

> The two step process which correlates axial rotation with the clocks
> in 24 hours/360 degrees precisely is now open for anyone who cares to
> explain it as a shared astronomical heritage which is gorgeous and
> pragmatic.

Yes (apart from not being exact) it is indeed gorgeous; but it is 
emphatically not exclusive of other more exact and useful means of 
expressing the relationship between heavens and earth. 



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