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Time and timekeeping



 
 
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  #1  
Old October 25th 17, 06:59 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Time and timekeeping

The theorists assume they are discussing time when it is really timekeeping they are referring to. Of course this goes back to a person who decided to define timekeeping as time itself using a calendar based facility known as the Equation of Time -

"Absolute time, in astronomy, is distinguished from relative, by the
equation or correlation of the vulgar time. For the natural days are
truly unequal, though they are commonly considered as equal and used
for a measure of time; astronomers correct this inequality for their
more accurate deducing of the celestial motions...The necessity of
which equation, for determining the times of a phænomenon, is evinced
as well from the experiments of the pendulum clock, as by eclipses of
the satellites of Jupiter." Principia

Before you all run back to relativity as an utterly bankrupt notion based on absolute/relative time,space and motion run back further and deal with the actual mess Newton created at the expense of astronomy and timekeeping. Of course intellectual rednecks only want to know enough that suits them but that is what rednecks always do.



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  #2  
Old October 26th 17, 09:13 AM posted to sci.astro.amateur
Martin Brown[_3_]
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Default Time and timekeeping

On 25/10/2017 18:59, Gerald Kelleher wrote:
The theorists assume they are discussing time when it is really
timekeeping they are referring to. Of course this goes back to a
person who decided to define timekeeping as time itself using a
calendar based facility known as the Equation of Time -


The equation of time is just the first order correction for a whole host
of other effects that alter the spin of the Earth. The transit of the
sun makes for a very poor time standard by comparison with a star.

Astronomers realised this a very long time ago by the Babylonians.

http://www.precisedirections.co.uk/S...rly%20Days.pdf


Pragmatically people divided daylight and nighttime into 12 hours of
length which varied radically with the seasons (at least in the UK).

Monastery clock pendulums at the time were adjustable to allow longer or
shorter "hours" for day and night time away from the equinoxes.

https://en.wikipedia.org/wiki/Roman_timekeeping

--
Regards,
Martin Brown
  #3  
Old October 26th 17, 02:12 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 889
Default Time and timekeeping

On Thursday, October 26, 2017 at 9:13:32 AM UTC+1, Martin Brown wrote:
On 25/10/2017 18:59, Gerald Kelleher wrote:
The theorists assume they are discussing time when it is really
timekeeping they are referring to. Of course this goes back to a
person who decided to define timekeeping as time itself using a
calendar based facility known as the Equation of Time -


The equation of time is just the first order correction for a whole host
of other effects that alter the spin of the Earth. The transit of the
sun makes for a very poor time standard by comparison with a star.


This is a foolish statement, the 'Equation of Time' is a timekeeping facility that only works within the calendar framework so before the theorists so running after a notion that 'clocks measure' time, the job of a clock is merely to maintain a constant pace in terms of the AM/PM cycle or its subdivisions of hours,minutes and seconds. The language of astronomy and timekeeping is to determine where the dynamics of the Earth's orbital motion (producing the natural inequality in the total length for each meridian crossing of the Sun) meshes with human devised clock noon. The primary understanding is that the natural day with its variability is the anchor for the 24 hour weekday and the division into constant hours ,minutes and seconds.

The creation of the Lat/Long system imposed on the Earth's daily rotational geometry in terms of time/distance separation (15 degrees/hour) exploits the equalizing effects of the Equation of Time so that the 'average' 24 hour day is translated into 'constant' rotation at 15 degrees per hour, 1 degree for every 4 minutes or any other correlation. It is that neat trick of converting 'average' to 'constant' that allowed for terrestrial Lat/Long coordinates and more importantly the close but not exact correspondence between the 24 hour weekday and one rotation.

The RA/Dec framework is basically a shortcut which is built on the previous principle supplied by the Equation of Time. The EoT required a meridian line which followed the particular meridian from pole to pole where the observation is made. Only when this line was constructed could the observer determine natural noon on that meridian -

" Draw a Meridian line upon a floor... and then hang two plummets, each by a small thred or wire, directly over the said Meridian, at the distance of some 2. feet or more one from the other, as the smalness of the thred will admit. When the middle of the Sun (the Eye being placed so, as to bring both the threds into one line) appears to be in the same line exactly... you are then immediately to set the Watch, not precisely to the hour of 12. but by so much less, as is the Aequation of the day by the Table." Huygen's

https://adcs.home.xs4all.nl/Huygens/06/kort-E.html

The Ra/Dec observations are homocentric ,meaning that any two forefront references do not follow the Earth's rotation from pole to pole but track around the observer. The crucial point here is that unless an observer actually goes further back in history to the creation of the 4 year/ 4 orbital period calendar cycle can they make some progress and discover why it is important not to mix up the reference systems for either the Earth's daily/orbital motions or timekeeping. This language is as definite and intricate as computer language or any engineering language but few are familiar with the components.

Your description is purpose designed for calendar based RA/Dec predictions but at the expense of an astronomy that is bursting at the seams with new imaging. I have learned your language but unfortunately you may have to go back further in history to look at the few other astronomical/timekeeping languages to sort the whole thing out in an honest way.







  #4  
Old October 26th 17, 03:23 PM posted to sci.astro.amateur
Quadibloc
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Default Time and timekeeping

On Thursday, October 26, 2017 at 7:12:08 AM UTC-6, Gerald Kelleher wrote:

This is a foolish statement, the 'Equation of Time' is a timekeeping
facility that only works within the calendar framework so before the
theorists so running after a notion that 'clocks measure' time, the job
of a clock is merely to maintain a constant pace in terms of the AM/PM
cycle or its subdivisions of hours,minutes and seconds.


This nicely sums up *precisely* where you have gone wrong.

Time is a fundamental property of the whole Universe.

So it doesn't speed up or slow down because of the details of the motion
of one little planet going around one little star.

You seem to think that the *time of day* is time itself. Which is simply silly; if you go east by 15 degrees of longitude, the time of day is an hour later - but at the same moment of time.

What clocks measure, which advances at a uniform pace, is what is useful
for telling how long it takes to bake a cake... or how long it takes for
crystals to dissolve... or how long it takes for an oscillation
generated by an inductor-capacitor network to complete.

And it is precisely because that is time itself, whereas the time of day
is simply an accident of location, that the rotational period of the
Earth is not a complete cycle of the time of day, but instead a rotation
of the kind that is uniform within true time - the so-called "sidereal
day".

John Savard
  #5  
Old October 26th 17, 04:07 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Time and timekeeping

If people want to create a software language to model the motions of the Earth and other planets, solar system structure or galactic inputs as distinct from predicting astronomical events using celestial sphere software (RA/Dec) then there is a lot of amendments required. Let those who follow modelling using RA/Dec stick with it but even at a basic level it is absurd despite its usefulness for predicting events as times and dates.

Already a sci-fi nuisance attached himself to my response despite an explanation which allows the 'average' 24 hour day to substitute for 'constant' rotation at a rate of 15 degrees per hour, 1 degree per 4 minutes, ect. I wouldn't give these nuisances the satisfaction of knowing why RA/Dec can't compete with the Lat/Long system when it comes to the intricate principles and references involved, it is unbearable to suffer their graffiti in these threads although it may give them some pleasure.

I understand that whoever creates the template for modelling motions outside celestial sphere software will make a fortune as all the agencies or organizations use the calendar based framework inherited from the Greeks and later astronomers.
  #6  
Old October 26th 17, 06:21 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 889
Default Time and timekeeping

On Thursday, October 26, 2017 at 9:13:32 AM UTC+1, Martin Brown wrote:

Astronomers realised this a very long time ago by the Babylonians.


[ In 1669, Christiaan Huygens (1629 - 1695) published the first ‘modern’ table of the Equation of Time in his “Instructions Concerning the Use of Pendulum-Watches for finding the Longitude at Sea”. Thereafter the Equation of Time became the concern of time tellers and thus sundial makers. It was around this time that the term Equatio Dierum translated to Equation of Time. ]


http://www.precisedirections.co.uk/S...rly%20Days.pdf




Thank you for posting this website however the original proposal of Huygens is flawed in respect to the Equation of Time as I have pointed out many times using his own words. It helps genuine theorists comes to grips with Newton's attempt to explain the Equation of Time as 'absolute/relative time' even though it is a timekeeping facility.

Newton's idea that geocentric observations transfer into heliocentric conclusions is based on Huygens flawed principle which attempts to squeeze the Equation of Time into the orbital period of the Earth -

" Here take notice, that the Sun or the Earth passeth the 12. Signes, or makes an entire revolution in the Ecliptick in 365 days, 5 hours 49 min. or there about, and that those days, reckon'd from noon to noon, are of different lenghts; as is known to all that are vers'd in Astronomy. Now between the longest and the shortest of those days, a day may be taken of such a length, as 365 such days, 5. hours &c. (the same numbers as before) make up, or are equall to that revolution:" Huygens

Your website references Ptolemy but here is where the original Sun centered astronomers got into trouble which they couldn't resolve or could only half resolve.

". . . the ancient hypotheses clearly fail to account for certain important matters. For example, they do not comprehend the causes of the numbers, extents and durations of the retrogradations and of their agreeing so well with the position and mean motion of the sun. Copernicus alone gives an explanation to those things that provoke astonishment among other astronomers, thus destroying the source of astonishment, which lies in the ignorance of the causes." Kepler 1596, Mysterium Cosmographicum

If anyone has regard for the astronomers going all the way back to antiquity they will not take the opportunity to focus on me but look at the necessary partitioning between predictive astronomy (calendar based) and a new software program that models motions and structure outside a celestial sphere contrivance.



  #7  
Old October 27th 17, 01:50 PM posted to sci.astro.amateur
Martin Brown[_3_]
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Default Time and timekeeping

On 26/10/2017 14:12, Gerald Kelleher wrote:
On Thursday, October 26, 2017 at 9:13:32 AM UTC+1, Martin Brown
wrote:
On 25/10/2017 18:59, Gerald Kelleher wrote:


The theorists assume they are discussing time when it is really
timekeeping they are referring to. Of course this goes back to a
person who decided to define timekeeping as time itself using a
calendar based facility known as the Equation of Time -


The equation of time is just the first order correction for a whole
host of other effects that alter the spin of the Earth. The transit
of the sun makes for a very poor time standard by comparison with a
star.


This is a foolish statement, the 'Equation of Time' is a timekeeping
facility that only works within the calendar framework so before the
theorists so running after a notion that 'clocks measure' time, the
job of a clock is merely to maintain a constant pace in terms of the
AM/PM cycle or its subdivisions of hours,minutes and seconds. The


The problem (even from antiquity) is that our clocks became more
accurate than the motion of the sun. In antiquity the Babylonians were
aware that the sun moves across the sky at a variable rate which was
quite an achievement with the naked eye instruments of the day.

Over 2 thousand years later you still haven't grasped those basics.

Our atomic clocks now maintain insane accuracy such that the seasonal
change in the moment of inertia of the Earth as the leaves fall from
northern hemisphere trees is detectable in the discreprancy between
(atomic) terrestrial dynamical time and the rotation of the Earth.

IERS Bulletin C ann the prediction of leap seconds is online he

http://hanksville.org/futureofutc/pr...522_Gambis.pdf

Genuine astronomers might enjoy reading it.

--
Regards,
Martin Brown
  #8  
Old October 27th 17, 02:56 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 889
Default Time and timekeeping

On Friday, October 27, 2017 at 1:50:55 PM UTC+1, Martin Brown wrote:
On 26/10/2017 14:12, Gerald Kelleher wrote:
On Thursday, October 26, 2017 at 9:13:32 AM UTC+1, Martin Brown
wrote:
On 25/10/2017 18:59, Gerald Kelleher wrote:


The theorists assume they are discussing time when it is really
timekeeping they are referring to. Of course this goes back to a
person who decided to define timekeeping as time itself using a
calendar based facility known as the Equation of Time -

The equation of time is just the first order correction for a whole
host of other effects that alter the spin of the Earth. The transit
of the sun makes for a very poor time standard by comparison with a
star.


This is a foolish statement, the 'Equation of Time' is a timekeeping
facility that only works within the calendar framework so before the
theorists so running after a notion that 'clocks measure' time, the
job of a clock is merely to maintain a constant pace in terms of the
AM/PM cycle or its subdivisions of hours,minutes and seconds. The


The problem (even from antiquity) is that our clocks became more
accurate than the motion of the sun. In antiquity the Babylonians were
aware that the sun moves across the sky at a variable rate which was
quite an achievement with the naked eye instruments of the day.

Over 2 thousand years later you still haven't grasped those basics.


So much for correcting a reckless conclusion which tried to subvert the principles of the Lat/Long system with the nonsensical Ra/Dec format, even pointing out that both these principles are an outrigger of the calendar framework seems to pass you by.

It is not a question of understanding but actually enjoying how the 'average' 24 hour weekday gets translated into a 'constant' rotational rate of 15 degrees per hour and using these accurate clocks it is then possible to make a homocentric observation using a rotating celestial sphere around the observer using two sticks and a clock which registers the average 24 hour day and the constant rates of timekeeping (hours,minutes,seconds).

So it is not 'your' clocks ,timekeeping is the property of all humanity and the myriad of achievements currently disrupted by your crowd.






Our atomic clocks now maintain insane accuracy such that the seasonal
change in the moment of inertia of the Earth as the leaves fall from
northern hemisphere trees is detectable in the discreprancy between
(atomic) terrestrial dynamical time and the rotation of the Earth.

IERS Bulletin C ann the prediction of leap seconds is online he

http://hanksville.org/futureofutc/pr...522_Gambis.pdf

Genuine astronomers might enjoy reading it.

--
Regards,
Martin Brown


  #9  
Old October 30th 17, 11:38 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 889
Default Time and timekeeping

On Friday, October 27, 2017 at 1:50:55 PM UTC+1, Martin Brown wrote:


Our atomic clocks now maintain insane accuracy such that the seasonal
change in the moment of inertia of the Earth as the leaves fall from
northern hemisphere trees is detectable in the discreprancy between
(atomic) terrestrial dynamical time and the rotation of the Earth.


I am sure this entertains those who know no better but if things were normal we would be discussing the real variations which arise as a separate surface rotation throughout the planet's orbit.

The daylight side of the polar day is now well established as that location turns solely in response to the planet's orbital motion and, of course, turns parallel to the orbital plane -

https://www.usap.gov/videoclipsandmaps/spwebcam.cfm

The Equation of Time is a global correction therefore there are no hemispherical components as the accelerating and decelerating responses found in the orbital surface rotation show up in the varying length of each noon irrespective of location on the planet where the Sun comes into view each weekday.

Isolating daily and orbital surface rotations is a quest but it doesn't rely on falling leaves, it does have components like the largest single weather event on the planet like Arctic sea ice evolution so I face no real competition in terms of cause and effect in this matter.





  #10  
Old October 31st 17, 01:47 AM posted to sci.astro.amateur
palsing[_2_]
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Default Time and timekeeping

On Friday, October 27, 2017 at 6:56:03 AM UTC-7, Gerald Kelleher wrote:

So much for correcting a reckless conclusion which tried to subvert the principles of the Lat/Long system with the nonsensical Ra/Dec format...


Tell us, Gerald, what exactly is 'nonsensical' about the Ra/Dec format? It is essential for locating objects in the night sky, and in that regard, it is an essential tool for astronomers, both amateur and professional. Virtually everyone understands this very well, except, obviously, yourself. It has little, if anything, to do with timekeeping on Earth, and in no way is it attempting to "subvert the principles of the Lat/Long system"... now THAT notion is truly nonsensical!

It will take you many years to unlearn what you think you know about astronomy, for right now it is essentially nothing at all...
 




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