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Commentary on the description of Wallis



 
 
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  #1  
Old April 3rd 11, 07:23 PM posted to sci.astro.amateur
oriel36[_2_]
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Default Commentary on the description of Wallis

In 1666 or 20 years before a toxic strain of empiricism hijacked cause
and effect there were men discussing issues which have been more or
less dormant for the last 3 centuries -

http://books.google.com/books?id=RyB...ge&q&f=fals e

It may not be possible to work for people engaged presently in science
but it may be possible to work with people on this matter as I am sure
people have some fear approaching matters such as the Equation of Time
as these men approached it and they readily admit that they were
unclear as to what causes the natural noon cycles to vary from one
cycle to the next and where the Equation of Time fits in in terms of
planetary dynamics.

First things first,the variations in the natural noon cycles is best
understood in terms of the Earth's two types of daylight/darkness
cycles arising from two separate causes,the primary one is daily
rotation which causes the Sun to return to noon a full 365 times in
any year and the secondary daylight/darkness is understood best at the
polar coordinates which turn unevenly to the central Sun due to the
orbital motion of the planet and its orbital trait which turns to the
central Sun and coincident with its orbital period.

The original equalization of the 24 hour day did not involve the
Equation of Time but must have been derived from a careful sampling
method where ,for a given amount of natural noon cycles,there would
have been a total sample of the number of rotations divided equally to
arrive at the 24 hour day which in turn was used to gauge the annual
cycle which in turn allowed the refined number of cycles to total 1461
for 4 annual cycles and 365 1/4 or 365 days 5 hours 49 minutes for 1
annual cycle.

The application of planetary dynamics to this system is fraught with
intricacies yet the employment of physical brakes such as the limiting
number of rotations and day/night cycles a year,in this case no more
than a full 365, tend to ease the difficulties rather than create
confusion. Think of the Equation of Time as a new kid on the block,a
type of reasoning which uses the entire sequence of 1461 cycles or
rotations over a calendar cycle and it was John Harrison I believe who
first adapted the Equation of Time to the calendar system.

The system requires only the ability to acknowledge that the orbital
daylight/darkness cycle has a separate cause to the day/night cycle of
daily rotation hence the combination of both motions are observed in
the natural noon inequalities.Unlike Wallis,we can actually see the
dual turning to the Sun directly as the daily rotation of Uranus turns
parallel with the rings while the rings themselves turn almost at
right angles to the Sun denoting the way the planet turns once to the
Sun every 84 years.

http://hubblesite.org/newscenter/arc...99/11/video/b/

Readers are not asked to understand the difference between right
ascension and the Equation of Time as the guys in the late 17th
century couldn't be blamed for that but contemporary imaging allows
the reader to interpret two separate motions to the Sun directly and
then apply the same reasoning to the Earth.

  #2  
Old April 4th 11, 09:03 AM posted to sci.astro.amateur
Quadibloc
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Posts: 7,018
Default Commentary on the description of Wallis

On Apr 3, 12:23*pm, oriel36 wrote:

It may not be possible to work for people engaged presently in science
but it may be possible to work with people on this matter as I am sure
people have some fear approaching matters such as the Equation of Time
as these men approached it and they readily admit that they were
unclear as to what causes the natural noon cycles to vary from one
cycle to the next and where the Equation of Time fits in in terms of
planetary dynamics.


While I could not follow your link to the specific text you sought to
indicate - apparently the document preview is unavailable outside the
U.S. - I did some subsequent searching on the matter.

Wallis was himself responsible for having both the lunar theory of
Horrox (based on the ellipses of Kepler, and not using Newton's
gravity as far as I know) _and_ an essay by Flamsteed on the causes of
the Equation of Time.

So apparently he did consider the work of Flamsteed to have merit...

The system requires only the ability to acknowledge that the orbital
daylight/darkness cycle has a separate cause to the day/night cycle of
daily rotation hence the combination of both motions are observed in
the natural noon inequalities.


We *do* acknowledge this - which is why we say that the presence of
the orbital daylight/darkness cycle means that either one more, or one
less, rotations may take place during a year than the number of net
daylight/darkness cycles we experience, because both orbital motion
and rotation are present as causes of the daylight/darkness cycle.
(And it happens to be one more rotation, because the rotation of the
Earth and its orbit around the Sun are both counterclockwise.)

John Savard
 




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