Yes, the explanation you refer to above is the standard one used in physics. It is a model of the underlying reality which is useful for making predictions.
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Hello Ricmat
I would not intentionally put you on the spot but so far you probably have come closest to the difference between determining a cause as opposed to the consequences arising from some dynamic.For instance,nobody knows why the Earth turns in its daily rotation or orbits the central Sun but we experience the consequences of those motions in their barest form as day/night cycle and seasonal variations in daylight/darkness.
The ‘predictive’ part of Newton’s agenda requires attention because it comes directly from the ‘predictive’ Ra/Dec framework which was newly created by John Flamsteed as clocks and telescopes began to appear -
“With the invention of the telescope, it became possible for astronomers to observe celestial objects in greater detail, provided that the telescope could be kept pointed at the object for a period of time. The easiest way to do that is to use an equatorial mount for the telescope, which allows the telescope to rotate at the same rate as the earth. As the equatorial mount became widely adopted for observation, the equatorial coordinate system, which includes right ascension, was adopted at the same time for simplicity. The first star catalog to use right ascension and declination was John Flamsteed’s Historia Coelestis Britannica (1712, 1725).”
en.wikipedia.org/wiki/Right_ascension
Forgive me for ‘shouting’ as I dislike it ,but it is of such great importance that I need to stress the difference.
The geocentric and heliocentric astronomers had made decisions regarding solar system structure by discriminating planetary motions AGAINST the stellar background with Copernicus resolving the apparent backward motion of the planets by showing that the Earth’s own orbital motion accounts for it -
apod.nasa.gov/apod/image/0112/JuSa2000_tezel.gif
The key to organising the arrangement of planets around the central Sun is based on the length of time each planet returns to the same spot against the stellar background .The ‘periodic times’ argument is central to the heliocentric idea of switching the geocentric proposal of the Sun between Venus and Mars with the Earth’s orbital motion -
"Of all things visible, the highest is the heaven of the fixed stars.
This, I see, is doubted by nobody. But the ancient philosophers wanted to arrange the planets in accordance with the duration of the revolutions. Their principle assumes that of objects moving equally fast, those farther away seem to travel more slowly, as is proved in Euclid’s Optics. The highest planet is Saturn, which completes the biggest circuit in the longest time. Below it is Jupiter, followed by Mars.
With regard to Venus and Mercury, however, differences of opinion are found. For, these planets do not pass through every elongation from the sun, as the other planets do. Hence Venus and Mercury are located above the sun by some authorities, like Plato’s Timaeus [38 D], but below the sun by others, like Ptolemy [Syntaxis, IX, 1] and many of the modems. Al-Bitruji places Venus above the sun, and Mercury below it. " Copernicus
webexhibits.org/calendars/year-text-Copernicus.html
Briefly,Flamsteed’s Ra/Dec ‘predictive’ framework has the planets moving WITH the stellar background ,great for an observational convenience like telescopes but fundamentally a 365/366 calendar creation.In Flamsteed’s scheme,which Newton built on as ‘predictive’, the planets are like ornaments on a rotating Christmas tree and whereas Flamsteed may have convinced himself he was working off an annual orbital cycle of 365 days 5 hours 49 minutes,his scheme shows the horror of equable 365/366 days of the calendar system.
For whatever reasons that I cannot comprehend,mention Newton and everybody today feels compelled to shout ‘genius’,brilliant this or that but in fact Newton was busy distorting astronomical insights to get planetary motions to fit into his terrestial ballistics agenda.He shows no indication that he understands astonomical timekeeping principles nor that Flamsteed made a shocking basic error.
At the end of the 19th century,some strong individuals had enough of Isaac yet could not figure out how he was distorting timekeeping and heliocentric principles -
“This absolute time can be measured by comparison with no motion; it has therefore neither a practical nor a scientific value; and no one is justified in saying that he knows aught about it. It is an idle metaphysical conception.”
Mach, Analyse der Empfindungen, 6th ed.
The thing about it that absolute/relative time as Newton has it represents the difference between unequal natural noon and 24 hour clock noon which in turn was the basis for daily rotation in 24 hours through 360 degrees -
“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;” Principia
I have urged some particpants to go back and look at how Copernicus reasoned that the Earth has an orbital motion by resolving retrogrades and how the 24 hour day is created from unequal natural noon and applied to the daily cycle as a 24 hour/360 degrees constant as a means to find their way out of the labyrinth that Newton created .
The ‘laws of motion’ otherwise known as the ’ Universal theory of gravitation’ is a bright shining lie that conceals much and reveals nothing worthwhile,that is not an opinion but a technical and astronomical certainty.
So,who wishes to work through this in a 21st century setting ?.
