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Offline GreatATuin

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Comet Shoemaker–Levy 9
« on: April 25, 2020, 10:48:30 PM »
In 1993, a comet was discovered. Calculations showed that it would collide with Jupiter in July 1994.

As the fragments of the comet collided with the planet between July 16 and July 22, even amateur astronomers with small telescopes could see the effects of the impact, which were at least as visible as the famous "red spot".

How could such a prediction be made, more than a year before the event, without very precise knowledge of the orbits of Jupiter and the comet? How does that fit with a flat Earth view claiming that little is known about the celestial bodies and their distances, and predictions are only based on patterns? This collision was the first one ever observed between two bodies of the Solar System, it's hard to find a pattern when there's a single occurrence.
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Offline Tom Bishop

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Re: Comet Shoemaker–Levy 9
« Reply #1 on: April 25, 2020, 11:59:41 PM »


It was discovered March 1993 and it appears to have been predicted to impact Jupiter in May or June 1993. Not even a complete orbit. They predicted a partial orbit.

I can't find the method used to predict the orbit, but I would bet that it's probably the epicycle method of prediction used elsewhere in astronomy.
« Last Edit: April 26, 2020, 12:04:30 AM by Tom Bishop »
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Re: Comet Shoemaker–Levy 9
« Reply #2 on: April 26, 2020, 01:16:14 AM »
It was discovered March 1993 and it appears to have been predicted to impact Jupiter in May or June 1993. Not even a complete orbit. They predicted a partial orbit.

I can't find the method used to predict the orbit, but I would bet that it's probably the epicycle method of prediction used elsewhere in astronomy.

It was discovered on March 24, 1993 and on May 22, 1993 a prediction was published indicating it was likely going to hit Jupiter on July 25, 1994.

It hit Jupiter between July 16 and 22, 1994.

They were only three days off, 14 months in advance, a month after discovering it.

This is extremely strong evidence that the calculations used in modern astronomy work.

Calling them "patterns" with no knowledge of how they were actually made or any references is not evidence at all.

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Re: Comet Shoemaker–Levy 9
« Reply #3 on: April 26, 2020, 02:50:18 AM »
It's only a segment of an orbit, regardless of whether it took 14 months.

Did I call them patterns or did I say that I would bet that a method was similar to another method?
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Re: Comet Shoemaker–Levy 9
« Reply #4 on: April 26, 2020, 03:27:59 AM »


It was discovered March 1993 and it appears to have been predicted to impact Jupiter in May or June 1993. Not even a complete orbit. They predicted a partial orbit.

I can't find the method used to predict the orbit, but I would bet that it's probably the epicycle method of prediction used elsewhere in astronomy.

I'm not sure what a partial orbit versus a complete orbit has to do with anything. In any case, you are wrong in terms of it probably being an epicycle prediction. Yeomans, D. K. & Chodas are the ones who calculated just when the fragments and which ones would impact Jupiter and where on Jupiter. There's this:


http://adsabs.harvard.edu/full/1994BAAS...26R1022Y

Not much is known about the celestial bodies and their distances.

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Offline Tom Bishop

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Re: Comet Shoemaker–Levy 9
« Reply #5 on: April 26, 2020, 03:42:20 AM »
I clicked on your link and saw that the first page described how it was using perturbative analysis, which are epicycle methods.

"The equations of motion include perturbations due to all nine planets"

Perturbations = The modern epicycles with a gravitational twist
« Last Edit: April 26, 2020, 03:47:03 AM by Tom Bishop »
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Re: Comet Shoemaker–Levy 9
« Reply #6 on: April 26, 2020, 04:01:07 AM »
I clicked on your link and saw that the first page described how it was using perturbative analysis, which are epicycle methods.

"The equations of motion include perturbations due to all nine planets"

Perturbations = The modern epicycles with a gravitational twist

With a relativistic twist and supported by data from the 4 Galilean satellites. And don't forget the use of the disruption model developed by Sekanina, Zdenek; Chodas, Paul W.; Yeomans, Donald K:

Tidal Disruption and the Appearance of Periodic Comet Shoemaker-Levy 9

A unified model is presented that quantitatively interprets the observed characteristics of the nuclear train, the two dust trails, and the tail region of P/Shoemaker-Levy 9 in terms of a collisionally modified rotation velocity distribution of the comet's debris.

https://trs.jpl.nasa.gov/handle/2014/36567

Calculated and predicted through modern means, not just perturbations. And they were spot on.
Not much is known about the celestial bodies and their distances.

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Re: Comet Shoemaker–Levy 9
« Reply #7 on: April 26, 2020, 04:26:22 AM »
I clicked on your link and saw that the first page described how it was using perturbative analysis, which are epicycle methods.

"The equations of motion include perturbations due to all nine planets"

Perturbations = The modern epicycles with a gravitational twist

Im not certain that equal sign is right. I found this:

https://arxiv.org/abs/0807.2708

This article derives Copernicus epicycles from Newtonian gravity using linear algebra. It shows that by taking a perturbed circular orbit (from weak gravitational effects) Newtonian gravity can explain the observations made by early astronomers.

This sounds like a good thing for Newtonian gravity: it is consistent with observations.

So it doesn’t appear from this that perturbations are re-vamped epicycles, but instead that Newtonian gravity has the power to explain even very old observations.
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Offline Tom Bishop

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Re: Comet Shoemaker–Levy 9
« Reply #8 on: April 26, 2020, 05:03:02 AM »
Dr. Gopi Krishna Vijaya says that astronomers are really using epicycles with a gravitational disguise.

Replacing the Foundations of Astronomy - .pdf

Epicycles Once More

“ Following the Newtonian era, in the 18th century there were a series of mathematicians – Bernoulli, Clairaut, Euler, D’Alembert, Lagrange, Laplace, Leverrier – who basically picked up where Newton left off and ran with it. There were no descendants to the wholistic viewpoints of Tycho and Kepler, but only those who made several improvements of a mathematical nature to Newtonian theory. Calculus became a powerful tool in calculating the effects of gravitation of all the planets upon each other, due to their assumed masses. The motion of the nearest neighbor – the Moon – was a surprisingly hard nut to crack even for Newton, and several new mathematical techniques had to be invented just to tackle that.

In the process, a new form of theory became popular: Perturbation theory. In this approach, a small approximate deviation from Newton's law is assumed, based on empirical data, and then a rigorous calculation of differential equation is used to nail down the actual value of the deviation. It does not take much to recognize that this was simply the approach taken before Kepler by Copernicus and others for over a thousand years – adding epicycles to make the observations fit. It is the same concept, but now dressed up in gravitational disguise: ”



“ In other words, the entire thought process took several steps backwards, to redo the same process as the Ptolemaic - Copernican epicycle theory, only with different variables. The more logical way of approach would have been to redirect the focus of the improved mathematical techniques to the assumptions in Newton’s theory, but instead the same equations were re-derived with calculus, without examining the assumptions. Hence any modern day textbook gives the same derivation for circular and elliptical motion that Newton first derived in his Principia. The equivalence of the epicycle theory and gravitational theory has not been realized, and any new discovery that fits in with the mathematical framework of Newtonian gravity is lauded as a “triumph of the theory of gravitation.” In reality, it is simply the triumph of fitting curves to the data or minor linear extrapolations – something that had already been done at least since 2nd century AD. Yet the situation is conceptually identical. ”
« Last Edit: April 26, 2020, 07:03:28 AM by Tom Bishop »
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Offline GreatATuin

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Re: Comet Shoemaker–Levy 9
« Reply #9 on: April 26, 2020, 07:13:51 AM »
Are you arguing they couldn't make the prediction they did make?

Do we, or do we not, know the orbit of Jupiter precisely enough to predict more than one year in advance, not only that a comet will hit it, but also where on the planet it will hit?

Is that compatible with not knowing the distances between celestial bodies?
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Re: Comet Shoemaker–Levy 9
« Reply #10 on: April 26, 2020, 11:12:11 AM »
Please try to post in the correct board in the future.

Please not that this is not the right board for asking entry-level FET questions. If your post starts with "I'm new and I just wanted to ask" or "The Earth can't be flat because of this concept", you're in the wrong place and should probably be looking at the Flat Earth Theory board (and the FAQ).
Read the FAQ before asking your question - chances are we've already addressed it.
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Re: Comet Shoemaker–Levy 9
« Reply #11 on: April 26, 2020, 01:16:54 PM »
Please try to post in the correct board in the future.

Please not that this is not the right board for asking entry-level FET questions. If your post starts with "I'm new and I just wanted to ask" or "The Earth can't be flat because of this concept", you're in the wrong place and should probably be looking at the Flat Earth Theory board (and the FAQ).
It didn't look particularly "entry-level" to me, it's not addressed in the FAQ and doesn't even directly deal with the shape of the Earth: it's about our knowledge of the position and movement of celestial bodies.

But well, your forum your rules, I'm fine with either board.
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Re: Comet Shoemaker–Levy 9
« Reply #12 on: April 26, 2020, 01:17:00 PM »
It's only a segment of an orbit, regardless of whether it took 14 months.

Did I call them patterns or did I say that I would bet that a method was similar to another method?

Don't be disingenuous.  Your only actual reference to these "similar methods" was your Wiki page titled "Astronomical Prediction Based on Patterns" so don't claim patterns had nothing to do with your answer. 

The prediction worked, it was extremely accurate, it shows that the math and theory is correct and we understand how planets and comets and bodies move, and even collide.

And that segment was 14 months of an 18 month orbit, very nearly a full orbit. 


Offline BRrollin

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Re: Comet Shoemaker–Levy 9
« Reply #13 on: April 26, 2020, 03:12:50 PM »
Dr. Gopi Krishna Vijaya says that astronomers are really using epicycles with a gravitational disguise.

Replacing the Foundations of Astronomy - .pdf

Epicycles Once More

“ Following the Newtonian era, in the 18th century there were a series of mathematicians – Bernoulli, Clairaut, Euler, D’Alembert, Lagrange, Laplace, Leverrier – who basically picked up where Newton left off and ran with it. There were no descendants to the wholistic viewpoints of Tycho and Kepler, but only those who made several improvements of a mathematical nature to Newtonian theory. Calculus became a powerful tool in calculating the effects of gravitation of all the planets upon each other, due to their assumed masses. The motion of the nearest neighbor – the Moon – was a surprisingly hard nut to crack even for Newton, and several new mathematical techniques had to be invented just to tackle that.

In the process, a new form of theory became popular: Perturbation theory. In this approach, a small approximate deviation from Newton's law is assumed, based on empirical data, and then a rigorous calculation of differential equation is used to nail down the actual value of the deviation. It does not take much to recognize that this was simply the approach taken before Kepler by Copernicus and others for over a thousand years – adding epicycles to make the observations fit. It is the same concept, but now dressed up in gravitational disguise: ”



“ In other words, the entire thought process took several steps backwards, to redo the same process as the Ptolemaic - Copernican epicycle theory, only with different variables. The more logical way of approach would have been to redirect the focus of the improved mathematical techniques to the assumptions in Newton’s theory, but instead the same equations were re-derived with calculus, without examining the assumptions. Hence any modern day textbook gives the same derivation for circular and elliptical motion that Newton first derived in his Principia. The equivalence of the epicycle theory and gravitational theory has not been realized, and any new discovery that fits in with the mathematical framework of Newtonian gravity is lauded as a “triumph of the theory of gravitation.” In reality, it is simply the triumph of fitting curves to the data or minor linear extrapolations – something that had already been done at least since 2nd century AD. Yet the situation is conceptually identical. ”

Hmm, I see your point. One can draw many parallels as this author has done. But this description does not gel with the history of science. It is almost as though the author comments on the intention of those who developed the subject. Epicycles fell out of favor because it was descriptive rather than explanatory. Newton provided the explanation.

Of course, since both involve circular geometry, it is not a surprise that one can find mathematical transformations between the two. But over interpreting that would be a mistake.

At any rate, it is clearly confirmed from the article I posted that the mathematical theory (which is what matters in the end) predicts epicycles, and not the other way around.
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Re: Comet Shoemaker–Levy 9
« Reply #14 on: April 27, 2020, 12:45:31 AM »
Dr. Gopi Krishna Vijaya says that astronomers are really using epicycles with a gravitational disguise.

Replacing the Foundations of Astronomy - .pdf

I read Dr. Gopi Krishna Vijaya’s paper. Interesting until I got to who he recommends as far as researchers in this space - One recommended individual, Miles Mathis, stood out as I have read his work before. Dr. Gopi writes:

"Miles Mathis has independently detected both the problems with the conventional explanations for orbital motion as well as the need for an outward force against gravity, and has also, among other things, shown how Lagrange implicitly assumed it in his equations.

Miles Mathis is the same guy who claims Pi = 4, from his paper:

Abstract: I show that in all kinematic situations, π is 4.

And has page after page of what he considers fake, just a smattering of Mathis’ work:

PAPER UPDATE, added 3/11/20, The Lincoln Assassination. I show that we now have the grand slam: Lincoln was a gay Jewish actor who faked his death. See p. 29.
NEW PAPER, added 10/10/19, The 22 July Massacre in Norway was Fake, part 1. This is the Breivik event, where 77 people were allegedly killed. You probably already know it didn't happen, but here I do the world the favor of proving it. I also tie it to many other events and people.
NEW PAPER, added 4/17/15, Stephen Hawking died and has been replaced. I show lots of photographic evidence that Hawking died in 1985 and has been played by an impostor since then.
NEW PAPER, added 9/29/17, Looks like the Bushes are Jewish, too. Another big day at the genealogy sites and the peerage.

Mathis is a crackpot and Dr. Gobi cites him as "Other researchers (who) have shed additional light on these phenomena. Sullies the whole thing with the credibility meter plummeting.
Not much is known about the celestial bodies and their distances.

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Offline Tom Bishop

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Re: Comet Shoemaker–Levy 9
« Reply #15 on: April 27, 2020, 01:09:10 AM »
Physics hero Issac Newton believed in alchemy, young earth creationism, and made end-of-the-world predictions. That doesn't make everything Newton ever wrote to be wrong or uncitable, however. People can cite Newton without believing his other stuff. He believed in that other stuff, yet is somehow called the 'greatest physcist to have ever lived'. Vijaya is referencing something because he thinks it's correct.

By your posting you appear to be saying that you believe that this paper debunks you, and so you need to somehow discredit the author. And, desperately, you are telling us about something that someone else believes, who is not the author, that is unrelated to astronomy.

You can find several celestial mechanics experts calling perturbation theory to be based on epicycles as well - https://wiki.tfes.org/Astronomical_Prediction_Based_on_Patterns
 
Gravitation Vs. Relativity
Charles Lane Poor, Ph.D.
Professor Emeritus of Celestial Mechanics,
Columbia University

Motion of the Planets p.132

  “ The deviations from the “ideal” in the elements of a planet’s orbit are called “perturbations” or “variations”.... In calculating the perturbations, the mathematician is forced to adopt the old device of Hipparchus, the discredited and discarded epicycle. It is true that the name, epicycle, is no longer used, and that one may hunt in vain through astronomical text-books for the slightest hint of the present day use of this device, which in the popular mind is connected with absurd and fantastic theories. The physicist and the mathematician now speak of harmonic motion, of Fourier’s series, of the development of a function into a series of sines and cosines. The name has been changed, but the essentials of the device remain. And the essential, the fundamental point of the device, under whatever name it may be concealed, is the representation of an irregular motion as the combination of a number of simple, uniform circular motions. ”
« Last Edit: April 27, 2020, 01:29:58 AM by Tom Bishop »
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Re: Comet Shoemaker–Levy 9
« Reply #16 on: April 27, 2020, 01:57:43 AM »
Physics hero Issac Newton believed in alchemy, young earth creationism, and made end-of-the-world predictions. That doesn't make everything Newton ever wrote to be wrong or uncitable, however. People can cite Newton without believing his other stuff. He believed in that other stuff, yet is somehow called the 'greatest physcist to have ever lived'. Vijaya is referencing something because he thinks it's correct.

By your posting you appear to be saying that you believe that this paper debunks you, and so you need to somehow discredit the author. And, desperately, you are telling us about something that someone else believes, who is not the author, that is unrelated to astronomy.

You can find several celestial mechanics experts calling perturbation theory to be based on epicycles as well - https://wiki.tfes.org/Astronomical_Prediction_Based_on_Patterns
 
Gravitation Vs. Relativity
Charles Lane Poor, Ph.D.
Professor Emeritus of Celestial Mechanics,
Columbia University

Motion of the Planets p.132

  “ The deviations from the “ideal” in the elements of a planet’s orbit are called “perturbations” or “variations”.... In calculating the perturbations, the mathematician is forced to adopt the old device of Hipparchus, the discredited and discarded epicycle. It is true that the name, epicycle, is no longer used, and that one may hunt in vain through astronomical text-books for the slightest hint of the present day use of this device, which in the popular mind is connected with absurd and fantastic theories. The physicist and the mathematician now speak of harmonic motion, of Fourier’s series, of the development of a function into a series of sines and cosines. The name has been changed, but the essentials of the device remain. And the essential, the fundamental point of the device, under whatever name it may be concealed, is the representation of an irregular motion as the combination of a number of simple, uniform circular motions. ”

Simply, I just find your source material subject as stated before. And your reference on 'perturbations' is lovely, but the fact remains that these astronomers found, derived, calculated, and predicted a collision with Jupiter, when it would occur, and where it would occur on Jupiter's surface. And it was witnessed.

Now, how does FET account for that? Can FET make such a prediction? I think not. If and when FET can do all that, post it, in the mean time keep searching for how RE doesn't 'fit' observation. I'm looking forward to how FET can or does. Lay it on us how FET could make such a prediction.
Not much is known about the celestial bodies and their distances.

Offline BRrollin

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Re: Comet Shoemaker–Levy 9
« Reply #17 on: April 27, 2020, 04:28:04 AM »
Physics hero Issac Newton believed in alchemy, young earth creationism, and made end-of-the-world predictions. That doesn't make everything Newton ever wrote to be wrong or uncitable, however. People can cite Newton without believing his other stuff. He believed in that other stuff, yet is somehow called the 'greatest physcist to have ever lived'. Vijaya is referencing something because he thinks it's correct.

By your posting you appear to be saying that you believe that this paper debunks you, and so you need to somehow discredit the author. And, desperately, you are telling us about something that someone else believes, who is not the author, that is unrelated to astronomy.

You can find several celestial mechanics experts calling perturbation theory to be based on epicycles as well - https://wiki.tfes.org/Astronomical_Prediction_Based_on_Patterns
 
Gravitation Vs. Relativity
Charles Lane Poor, Ph.D.
Professor Emeritus of Celestial Mechanics,
Columbia University

Motion of the Planets p.132

  “ The deviations from the “ideal” in the elements of a planet’s orbit are called “perturbations” or “variations”.... In calculating the perturbations, the mathematician is forced to adopt the old device of Hipparchus, the discredited and discarded epicycle. It is true that the name, epicycle, is no longer used, and that one may hunt in vain through astronomical text-books for the slightest hint of the present day use of this device, which in the popular mind is connected with absurd and fantastic theories. The physicist and the mathematician now speak of harmonic motion, of Fourier’s series, of the development of a function into a series of sines and cosines. The name has been changed, but the essentials of the device remain. And the essential, the fundamental point of the device, under whatever name it may be concealed, is the representation of an irregular motion as the combination of a number of simple, uniform circular motions. ”

I’m confused. How can a paper “debunk” me? This isn’t personal. I’m offering different perspectives to further the discussion.

I cited a published paper of physics which shows the mathematical formalism. It stands for itself, and clearly details that Newtonian mechanics predicts epicycle observations. Do you wish to challenge the formalism?

From your reply, you appear to try to poison the well by discussing Newton’s failed ideas. That is irrelevant here. Also, I have never heard him called the greatest physicist. That’s a new one to me!

Next, you cite an opinion of a retired physicist, which is fine. Everyone may have their opinion. But the argument offered by him is best placed in an editorial - not a scientific journal. In fact, he ends the passage with a statement that confirms the formalism - obviously one can represent Newtonian mechanics by performing linear transformations on circles - the Newtonian gravitational force law has this embedded within it. And this comes as no surprise to anyone who understands it.

I hesitate to place much credence in TFES wiki sources, since I have found several instances throughout the fora of those sources being pseudoscience, along with evidence to support those statements.

In the end, any scientist may have their opinion on the philosophical implications of what the formalism shows. That is their prerogative. But that opinion should not be confused with the science - which are models themselves.

And the Newtonian model unequivocally demonstrates that epicycles follow as an observational consequence. And that fact can only be impeached by those who do not understand it.

But perhaps you see something in the math that they have all missed. I think that would be interesting to hear about!
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Offline Tom Bishop

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Re: Comet Shoemaker–Levy 9
« Reply #18 on: April 28, 2020, 11:39:52 PM »
How is a Columbia University Professor Emeritus of Celestial Mechanics an invalid source? I doubt that your credentials are as good to tell us how this works.

From the paper you posted, in the summary and conclusion section:

Quote
In this paper, we derived the Copernican system of epicycles from Newton’s gravitational force law in vector form
via linear perturbation theory in Clifford (geometric) algebra Cl2,0 of the plane.

It says that they derived Copernicus's epicycles with the Newtonian perturbation theory, which we had learned were also epicycles with a gravitational disguise.

Ptolmy's epicycle theory is described as follows:

  “ The circle is the geometric figure possessing perfect symmetry, so Ptolemy and earlier Greek astronomers began with the intuition that celestial bodies orbit in circles at uniform speed. Observations then determined the deviations from the ideal, which Ptolemy modeled using mathematical contrivances unrelated to physical principles (deferents, epicycles, and equants).

...Ptolemy’s science was superficially anti-Platonic in that he emphasized the role of careful observation. However, at a deeper level, his science was a logical application of Platonism; in astronomy and in optics, he started with the “perfect” model and then merely described without explanation the inherently unintelligible deviations from it. ”

Charles Lane Poor says:

"The deviations from the “ideal” in the elements of a planet’s orbit are called “perturbations” or “variations”.... In calculating the perturbations, the mathematician is forced to adopt the old device of Hipparchus, the discredited and discarded epicycle."

Dr. Vijaya said earlier:

"In the process, a new form of theory became popular: Perturbation theory. In this approach, a small approximate deviation from Newton's law is assumed, based on empirical data, and then a rigorous calculation of differential equation is used to nail down the actual value of the deviation. It does not take much to recognize that this was simply the approach taken before Kepler by Copernicus and others for over a thousand years – adding epicycles to make the observations fit. It is the same concept, but now dressed up in gravitational disguise"

Sounds pretty clear what the Newtonian Perturbation Theory is to me.
« Last Edit: April 29, 2020, 01:06:24 AM by Tom Bishop »
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Re: Comet Shoemaker–Levy 9
« Reply #19 on: April 28, 2020, 11:56:27 PM »
How is a Columbia University Professor Emeritus of Celestial Mechanics an invalid source? I doubt that your credentials are as good to tell us how this works.

Sounds like a smart guy, but he is beside the point. The point is, these astronomers found, derived, calculated, and predicted a collision with Jupiter, when it would occur, and where it would occur on Jupiter's surface. And it was witnessed.

How does FET account for that? Can FET make such a prediction? If so, how?
Not much is known about the celestial bodies and their distances.