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Messages - garygreen

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1
"The solutions we are going to present ... have been built from VSOP87"

Its not a description on how VSOP was programmed. The article is about taking data from VSOP and trying to manipulate it.

sort of, but not really.  read the abstract and section 3.  "solutions" means "the positions of the planets at a given time." 

vsop87 is a model of the solar system using only the elliptic parameters of each planetary orbit (semi-major axis, eccentricity, inclination, etc.).  but just knowing elliptic parameters isn't useful.  we want to know physical coordinates of the planets at a given time.  that's what vsop87a, vsop87b, etc, are for.  they're just outputting the positions of the planets in different coordinate/reference systems.

look at this table:


vsop87 describes each orbit in terms of the shape of the orbit (elliptic parameters).  vsop87a-e describe the positions of the planets in terms of different coordinate and reference systems (eg rectangular vs spherical).

all of these inputs and outputs are in terms of real, physical quantities: the shape of the orbit, the distance from the sun or barycenter, the mass of the object, etc.  i cannot find anything in these documents that describes the kind of pattern-counting that you say astronomy relies upon.

2
I am writing an article about VSOP. I have found some further information on how it works and am putting together an analysis.

I looked at your "it uses kepler" reference and found that the article you quoted is saying that the authors are trying to use kepler equations based on the data from VSOP to do something. It is not saying that VSOP is using kepler equations.

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?db_key=AST&bibcode=1988A%26A...202..309B&letter=.&classic=YES&defaultprint=YES&whole_paper=YES&page=309&epage=309&send=Send+PDF&filetype=.pdf

p. 311

Quote
4. The solutions we are going to present in this paragraph have been built from VSOP87
....

4.1 VSOP87A solution

This solution is built for the bodies given in Table 1. It is represented with heliocentric rectangular variable X, Y, Z

We must first solve Kepler's equations in order to...

nice ellipses.  the quote is "We must first solve Kepler's equation in order to get the expressions of the variables X, Y, Z." 

as in "[VSOP87a] is represented with heliocentric rectangular variables X, Y, Z...We must first solve Kepler's equation in order to get the expressions of the variables X, Y, Z."  i dunno how the literature could be any more clear on this point.  they are saying that vsop87a outputs heliocentric rectangular coordinates for the positions of the planets.  these coordinates are given by solving kepler's laws.

3
Can it do anything more than compute the presumed heliocentric elements?

what? whether or not it can computer the heliocentric coordinates is the thing we're arguing about.  your argument is that astronomers do not use a physical model of the planets to make predictions.  my argument is that vsop87 is exactly one such model.  it is a model of the solar system that predicts the positions of the planets in 3d space.  it's not merely a list of patterns.  the user inputs a time (eg i want to know where mars is in the solar system on april 20th, 2069), and vsop87 outputs heliocentric coordinates.

here's another astronomy site that gives a step-by-step tutorial on how to use vsop87: https://www.caglow.com/info/compute/vsop87
Quote
VSOP87 provides a method for computing the positions of the 8 planets (and the Sun) efficiently and accurately without the major headaches that astronomers from past centuries had to deal with.
...
It consists of a large number of periodic terms that are then added up together in a special way to produce the 3-dimensional heliocentric coordinates of any planet at any moment in time for thousands of years into the future and the past. These coordinates can then be converted through a few transformations into geocentric coordinates which can be used to show their position as seen from Earth.
...
The results of VSOP87C above are heliocentric coordinates, centered on the Sun. Since none of us actually live on the Sun, it might be more useful to obtain geocentric coordinates, centered on the Earth. Using rectangular coordinates, a simple transformation is all that is needed to convert.


4
Yet NASA has a secret working model of the Solar System, the heliocentric solution to the n-body problems, which can simulate all physical laws of the Solar System, which they are keeping privately to themselves?

pretty much everything you say in this post is dead wrong.  also no one is keeping secret models of the solar system.  my first post's last link shows you how to obtain the source code for vosp87 and run it yourself.

VOPS may produce some heliocentric interpretations. But what evidence is there to suggest that they are using those heliocentric concepts to predict the position of bodies in the sky?

There needs to be validation. How do you know that any prediction based on VOPS is done so based on heliocentric coordinates, rather than the geocentric (as seen from the earth) patterns the VOPS application is making those heliocentric coordinates from?

This program seems only good enough to tell us a few things about how a few things should be under the Heliocentric System, which astronomers then proceed to publish as fact about that model.

The numerous n-body problems in celestial mechanics shows that this application cannot be predicting future events based on the motions of a heliocentric system.

this is all completely wrong.  i wish you would bother to read the material i post instead of just making up your own version of things to critique.

5
Flat Earth Theory / Re: 100% undebunkable
« on: July 18, 2018, 08:35:14 PM »
However when looking at momentum of air for in-compressible air the equation for momentum needs to be expanded to



did they not teach you dimensional analysis at uni?

both sides reduce to kg s-1.  this is not a momentum equation.  it's a mass flow equation.

all this is saying is that for an incompressible fluid, you can't have sources or sinks of mass due to fluid flow.

6
Philosophy, Religion & Society / Re: Trump
« on: July 18, 2018, 06:30:01 PM »

7
From what I have read about VSOP the designers have done the following:
then you didn't read any of it very carefully.  you don't have to read all of it.  start with the abstracts.  or read the quotes i already posted.

peruse sections 2, 3, and 4.1.  vsop is a semi-analytic model of the solar system that takes as its input the orbital parameters of the planets (semi-major axis, distance from sun, eccentricity, inclination, etc.) and outputs their heliocentric positions in cartesian coordinates.  section 4.1 even explicitly says "We must first solve Kepler's equation in order to get the expressions of the variables X, Y, Z."

stuff about n-body problems
you don't understand the "problem" of the n-body problem in physics.  it's not that these problems are intractable or unsolvable; it's that they don't have analytic solutions.  that's not the same as saying they can't be solved.  it just means that there's no y=f(x) type expression that will tell you exactly how the system will evolve to an arbitrary level of precision.

let's suppose i have a proton and an electron some distance from one another.  there is an analytic solution, coulomb's law, that will tell me the force on each particle.  there's another analytic solution, newton's 420th law, that will tell me the acceleration of each particle, and so on and so on.

now let's suppose i have 69 particles (some protons, some electrons) arbitrarily arranged in space.  there is no analytic solution that will tell me exactly how the system will evolve over time.  but, since i can find the force between two particles, i can solve my analytic expression for every pair of particles and sum them all up.  i let my system evolve over a tiny time-step, then calculate the forces again, then let my system evolve a bit, etc.  that's what a numerical integration is. 

for example:
https://arxiv.org/abs/astro-ph/0111045
http://lnfm1.sai.msu.ru/~rastor/Books/Heggie_&_Hut-Gravitational_Million_Body_Problem.pdf

8
It has also been alleged that the seemingly simple math used in Astronomical calculation textbooks are "really" based on keplerian orbital dynamics. This article addresses that.

I have collected a number of resources showing that the perverted myth that the Round Earth Theory has been validated, to be false. I ask that any challenger in opposition demonstrates with real evidence that astronomy can predict the motions of the planets as they are described in the Round Earth Theory. More evidence than a link to an obscure pdf or unverified model. It will need to be demonstrated that a model, according to the geometry of the heliocentric system, can predict any positions of the planets at all!

an ephemeris is a table of positions of celestial objects like stars and planets and such.  these tables are derived from models of planetary positions.  one of the most widely used is a model called VSOP87.  btw this is the model from which NASA's eclipse tables are derived.

Planetary theories in rectangular and spherical variables - VSOP 87 solutions: http://adsabs.harvard.edu/abs/1988A&A...202..309B
Numerical expressions for precession formulae and mean elements for the Moon and the planets: http://adsabs.harvard.edu/abs/1994A&A...282..663S

here's a more readable overview that includes source code and instructions for using VSOP87 output positions: http://neoprogrammics.com/vsop87/index.html

Quote
In the simplest terms, the VSOP87 theory can be described as a long-term mathematical model of the solar system, specifically, the orbits of the major planets from Mercury to Neptune.
...
To compute the apparent positions of the planets as viewed from Earth, we first need to know where the planets and the Earth are in their orbits at the same moment.  This is the first and most laborious step in computing the apparent geocentric positions of the planets.
...
All the VSOP87 series do essentially the same thing.  They compute the co-ordinates of the planets for a given moment.
...
These are the raw, instantaneous, geometric, heliocentric co-ordinates from which the apparent geocentric ecliptical and equatorial co-ordinates and distance are subsequently derived.  By geometric co-ordinates we mean that no corrections for the location of the observer have yet been applied, such as for parallax, light-time, aberration, etc.  This is the actual location of the planet in space, not its apparent location to the eye.

9
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 15, 2018, 04:55:30 AM »
If the distances/attributes of the Round Earth Model can explain the moon tilt illusion for gibbous and crescent moons, I have absolutely no problem admitting that. As I have seen, it cannot. It cannot explain it, and this is why the literature is so vague about the matter.

the literature is silent on this problem because you are simply manufacturing the problem.  why would there be literature on a nonexistent problem?

As I said, the only time the moon and sun is seen in the sky is when they are on opposite sides of the sky. Otherwise, when the moon gets too close to the sun it disappears.

absurdly incorrect.  do a google search for "daytime moon."  you'll find many examples of crescent and gibbous moons.  how have you never seen a daytime crescent?

Find a panorama of the moon pointing into the sky above the sun and draw your string on it.

lol.  that you think this is a correct procedure demonstrates exactly how confused you are.  hint: straight lines in 3d space often stop being straight when you project them onto a 2d surface.  this is pretty much exactly the thing that i've been trying to tell you the whole time.  you're thinking of everything like an image.


What you are trying to do is say that the sky is a dome and that if you make vertical triangles along the top of the image, cut it out with scissors, and paste it together in a domish way that there is a way to make (force) the moon to point at the sun. By manipulating it in this manner you can also force the moon to point at any number of objects on that opposite horizon.

This is not coherent. It is the "celestial sphere" explanation given by some astronomers; but this explanation falls flat with the slightest breeze.

- The sun and moon are not painted on a celestial sphere around the earth where straight lines become curved.
- The sun and moon exist in regular geometric space where an arrow will always point to the object it is pointing at, not in an entirely different direction.

There will need to be a more coherent explanation than this celestial sphere theory. In RET the observers aren't in a planetarium with lines projected on a screen above them that turn into curves. The observers are in regular space.

what?  i've not said anything about triangles or celestial domes or anything else of the sort.

your argument is that the line perpendicular to the moon's terminator does not intersect the sun.  my argument is super simple: yes it does.  literally all you have to do demonstrate this fact to yourself is hold a taut string in front of your face.

instead you'd rather argue about cartoons and draw things on panoramas.  i don't get why.

10
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 15, 2018, 12:54:08 AM »
Astronomers do care about this sort of thing. Over the years every time this topic comes up and the audience provides quotes from astronomical texts, we see that astronomers don't really know why, have trouble explaining it, and mumble something vague about celestial spheres.

there isn't anything to explain.  you're just plain wrong that there's a problem to begin with.



you're saying that the line i've drawn won't point at the sun.  i'm telling you that it absolutely does, and you can demonstrate that it does by making your own straight line with a piece of string.  if you align one end of your string to be like the perpendicular line i've drawn on this moon, then you will find that the other end points at the sun.

you don't have to do any math.  you say this line doesn't point at the sun.  i say it does.  don't take my word for it.  see for yourself.

11
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 11:27:11 PM »
You can't explain this mathematically, and we have not seen a mathematical analysis by an astronomer using the distances and sizes in RET.

there's no math involved.  you're saying that a line isn't straight.  i'm saying it is.  you can use a line you know is straight (taut string) to demonstrate the fact of the matter for yourself.

stop arguing with thought experiments and cartoons.  you're better than that.  be an empiricist.

12
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 09:58:41 PM »
you're just thinking of the space as a 2d projection.  it's a 3d space.



Are you asserting that if Dexter fires his laser cannon, that the laser beam will leave the weapon and eventually intersect the horizon of the earth?

you're kinda just proving my point here. 

also i'm genuinely stunned that you of all people would use a carton as evidence of your claims.  instead of arguing about cartoons, why not just do the experiment?  i don't understand your reluctance.  it costs virtually no time or money.  as an empiricist, what reason could you possibly have not to see for yourself?

13
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 09:42:02 PM »
How does the string point to the direction of the sun if the sun is below the horizon and the moon is pointing upwards into the sky?

Are you telling us that any and all angles that are pointing upwards are eventually going to come back and meet the earth's horizon rather traveling out into space?  ::)

instead of imaging the experiment in your head, just do it.  it takes 20 seconds and a piece of string.  if you do the experiment, then you will see exactly why you're confused.

you're just thinking of the space as a 2d projection.  it's a 3d space.

14
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 01:13:58 PM »
Do the math.

no math required.  you only need a piece of string and maybe 20 seconds of your time.  if you would stop being a rationalist for a moment and actually do an experiment yourself, you'd see that the string points to the sun's location, even if the sun is below the horizon.

it seems like you're perfectly willing to depart from an empiricist mindset the moment it's inconvenient to your narrative.

15
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 02:09:24 AM »
The sun is below the horizon in the above image, Gary. The phase is pointing upwards away from the earth. If you track the straight path it goes out into space.

If you have a line angled above the horizontal, pointing upwards, it can't end up below the horizontal.

You are repeating nonsense you read in an astronomy book.

no, i've actually done it myself a bunch of times.  it always works.  i promise you: if you try it for yourself, you will see that i'm right.

you're just not thinking of the light's path through space correctly.  hint: it's not a coincidence that the moon was on the southeast horizon at sunset. 

16
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 14, 2018, 01:05:15 AM »
If I were to provide supporting evidence for that concept, I would point to the fact that the lunar phase does not point at the sun.

it always does.  you can demonstrate this to yourself with a piece of string.  hold the string taut to make it into a straight line.  now align it perpendicular to the moon's phase and see where it points.  be careful, because it's going to point right at the sun.

17
you'd have to take me to space and show me the disk.

18
Flat Earth Theory / Re: Full Moon Impossible on Flat Earth?
« on: July 12, 2018, 02:58:50 PM »
According to the NOAA website the calculator is based on a book called Astronomical Algorithms (PDF) by Jean Meeus. Reading closely, the book admits that the algorithms are just using statistical (pattern-based) methods:

you obviously haven't read it closely.  you just saw a chapter on curve fitting and moved on.

maybe try some of the other chapters:
16. angular separation
29. equation of kepler
30. elements of planetary orbits

tbh basically all the chapters are making geometric arguments.  he shows you the equations and defines all the terms.


19
Arts & Entertainment / Re: World Cup 2018
« on: July 11, 2018, 10:26:23 PM »
ugh who gives a shit about france/croatia.  lame.

20
Arts & Entertainment / Re: World Cup 2018
« on: July 10, 2018, 01:55:05 PM »
motherfuckers be scheduling meetings during the world cup.  ffs.  idiots.
Why don't you just book your calendar out during those times?
this is one of those unfortunate situations where the boss has returned from vacation and wants to retroactively micromanage the last two weeks of work.  my calendar is fucked.

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