Re: The great Western adaption

oriel36 wrote:
It would probably be of little use to point out
that it is impossible to work the annual orbital cycle of the Earth
using a system with an alternative number of days every 4th year but
such is Newtonian system which forces planetary motion into the
celestial sphere geometry above.

It is true that I see no particular problem with the year and the day
being incommensurable. Synodic or sidereal.

A location on Earth does Not,I repeat,does Not return to face the Sun
every 24 hours.My astronomical ancestors knew that the total length of
a day varies and created the Equation of Time (EoT) system which uses
noon to equalise the variations in the total length of a day to an
equable 24 hour day

I left out these complications, due to the elliptical nature of the
Earth's orbit, but I am glad that you are aware of them.

But don't those complications mean that the idea of a 24-hour axial
period that has any meaning *except* as the mean solar day, which is
what you seem to be advocating, is even *less* tenable?

Here you plummet back to your celestial sphere roots and that is
fairly usual,these posting are designed to make participants familiar
with the astronomical timekeeping side of things and no demands are
made beyond appreciating what our pre-Copernican and heliocentric
ancestors did and how they did it.

The celestial sphere defines a reference frame. Your "no demands are
made" statement here means I may be misunderstanding you in a different
sense.

Instead of claiming that the "celestial sphere" system - in its
simplicity and consistency - is _wrong_, you may simply be trying to
say that earlier systems of understanding the Solar System can also be
valid and consistent at least from the calendrical and horological
perspectives - even if we are pushed to the Newtonian celestial sphere
system when we try to account for the planets as moving bodies ruled by
Newton's Laws.

But you are advocating a heliocentric viewpoint, not a geocentric one,
and the idea of a heliocentric viewpoint *other* than the current
celestial sphere one - and other than Tycho Brahe's compromise, which
you seem to reject also - causes me a problem, since I can't visualize
what that viewpoint might *be*. Thus, I still don't understand what you
are saying some of our astronomical predecessors were doing.


The Earth does return to face in the *same direction* every 23 hours
and 56 minutes. That is a fact.

The 'fact' is that you are working on a 1461 day cycle broken into 3
years of 365 days and 1 year of 366 days,an impossible way to work with
the Earth's orbital motion and consequently the annual cycle.

It certainly is true that the Earth spends the *same* amount of time
every year going around the Sun once. But that time happens to be 365
days plus an odd fraction, somewhat less than 1/4 of a day. Why is it
untenable for that to happen?

The Earth travels slower the further it exists from the Sun and faster
the closer it exists,a simple attempt to fit the .986 degree sidereal
view will generate the ugly spectacle of the being contrary to this
Keplerian insight.

I assure you, when I use a 24 hour day on my clocks and watches, I am
not doing so with the intent of claiming that this mean solar day
matches exactly what I would see on a sundial; I am not denying the
Equation of Time!

In claiming that the 24 hour day is more real than the 23 hour and 56
minute day, it seems like you're trying to work the Equation of Time
backwards, but I'm sure _that_ is only a clumsy and overly-literal
reading on my part.

But it *really* seems to me that the Equation of Time only even begins
to make sense if we start from what you call the erroneous viewpoint of
Newton and Flamsteed, if we start from the celestial sphere as our
basis. So when I say I am baffled by your position, I am not being
merely rhetorical.

I may be doing a great disservice to the astronomical timekeepers who
origially created the clock and calendar systems which we use today
insofar as I am presenting where Flamsteed/Newton jumped the tracks by
creating celestial sphere geometry out of axial rotation and
orientation.

The heliocentric astronomers could easily adapt what the antecedent
astronomical timekeepers created insofar as the unused portion left
over from explaining the observed motion of the planets is axial
rotation.You can see the orbital motion of the Earth overtaking the
slower moving outer planets as an independent motion to affirm that we
see planetary motion around the Sun from a moving Earth -

http://antwrp.gsfc.nasa.gov/apod/image/0112/JuSa2000_tezel.gif

There is really nothing difficult in making the effort to draw the
conclusion that axial rotation causes the daily cycle and from there to
overlay the pre-existing Equation of Time system which creates the 24
hour day on top of the principle of axial rotation as being constant
and independent.Every single person here uses that principle day in and
day out whether they care to appreciate it or not but I would much
prefer if they did become familiar with this shared astronomical
timekeeping heritage,both pre-Copernican and heliocentric.

Perhaps in future I will be less inclined to explain where Newton went
astray for I am only obliged to present what is correct.

To the extent that you believe that Newton and Flamsteed went astray,
that the celestial sphere is not a good reference frame to start from,
I believe you to be mistaken. Furthermore, I feel that this error will
hinder your attempts to show how pre-Copernican and heliocentric
astronomy both share a common valid core of ideas between them by
rendering these unintelligible.

Using the celestial sphere as a starting point is not just
"indoctrination". It makes sense as the simplest place to start from
and disentangle all the other individual motions of the various bodies
in the Solar System. Because that's going to be the starting point of
the people reading your words, it will keep them from making sense to
these readers. I wish to grapple with your claim that Newton and
Flamsteed went astray, because I hope to show you how you have
misunderstood them.

John Savard

.

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