[Alsor on Axis wobbling (or not)]

[macaw]

According to the elementary principles of field theory: the body in equilibrium has the equipotential on boundary surface. Deformation of body is the result of equalizing the potential at the surface: external + internal = uniform at surface).

Traditional Lunisolar precession model is based only on Newton's law, therefore, is not compatible with the more general field theory (Newton did not know full field theory).

The explanation that I gave you is NOT based on Newtonian mechanics.
The "explanation" that you wrote is not based on "field theory".
In the end, nature does not care about "explanations", the bottom line is that observational data contradicts your theory and confirms the mainstream view.

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A. There are no tidal forces and rotation: a sphere - equipotential surface.

Correct.

B. Tidal forces present: the sphere is no longer equipotential surface, so changes the shape, and thus formed an elongated spheroid - with the equipotential surface.

Incorrect, the Earth is NOT a fluid and it is far from being a perfect fluid. This is the mistake that you keep repeating.

[Garrison]

I am only saying what in fact we register - the movement of the image.

Cosmology knows the various apparent phenomena such as superluminal motion, multiple images of the same object, distorted images of entire galaxies, various lenses, and many others, including perhaps some as yet unknown.
http://en.wikipedia.org/wiki/Caustic_(optics)

None of which in any way refutes the data supporting precession, unless you have any evidence that any of these phenomena could actually affect the measurement of precession

Very good question.
Solar System after eliminating the Earth's axis precession (the tropical year = period of Earth's orbit) will function correctly - no unnecessary adjustments, and anomalies.

But our model of the solar system functions perfectly well with precession, we send spaceprobes on complex orbital paths that require precise knowledge of the positions of the planets years in the future and, unless someone forgets to convert metric to imperial, they get where they are going. In other words the evidence doesn't support you contention of 'unnecessary adjustments.

I made some preliminary computer simulations, and there is no chance for any expansion of the period of Earth's orbit about the 20 minutes - phases drift drastically. You can not jump over the elementary laws of geometry.

You can create computer simulations to show anything, the question is how does the model compare to real world data? Does it make predictions that can be experimentally proven? If not then I'm afraid its potential a case of GIGO.

[captain swoop]

Since when is 'According to me' valid support or evidence for your own speculation?

[Alsor]

I think I'm starting to see where you're going wrong.

The Earth is exposed to multiple changing influences, which means the equipotential surface that the physical surface is trying to conform to is changing over time but since the Earth is not a fluid and is therefore rather unable to assume this idealized and dynamic shape instantly, your fundamental assumption is wrong.
At NO TIME is the physical surface of the Earth identical to the equipotential surface.

I have already spoken about this: we calculate the torque from the tidal potential gradients, and not from changes in those gradients!

According to the lunisolar precession model, the torque depends only on the current configuration of bodies. Configuration changes, so torque is simply averaged over time.


Earth is gravitationally bound, the shape does not change permanently!

[Alsor]

In the end, nature does not care about "explanations", the bottom line is that observational data contradicts your theory and confirms the mainstream view.

Your stream must go back to school.

Incorrect, the Earth is NOT a fluid and it is far from being a perfect fluid. This is the mistake that you keep repeating.

Never.
You do not understand, what means 'gravitationally bound'.
http://en.wikipedia.org/wiki/Earth_tide

And I well know what mistake you are doing from the beginning (a fairly obvious fact, nobody did not mention here).

[macaw]

Your stream must go back to school.



Never.
You do not understand, what means 'gravitationally bound'.
http://en.wikipedia.org/wiki/Earth_tide

And I well know what mistake you are doing from the beginning (a fairly obvious fact, nobody did not mention here).

If you repeatedly deny the obvious it doesn't mean that you are answering the challenges, it simply means that you are failing to respond. Personal attacks don't count as a valid answer, nor do diversions.

[Robert Tulip]

Sirius is not subject to the mythological precession.
http://en.wikipedia.org/wiki/Sothic_cycle
This gives Sirius the unusual characteristic of appearing to stay stable relative to the equinox and solstices, and for the same reason, the helical rising (or zenith) of Sirius does not slip through the calendar (at the precession rate of about one day per 71.6 years), as other stars do.

Hello Alsor, as it happens I have recently posted information that can help to correct your misconception (shared also by believers in a binary star theory) that observation of Sirius somehow disproves precession. The heliacal rising point of Sirius oscillates over the period of precession. At 1000 AD Sirius was at its furthest point from the South Celestial Pole, and so created the illusion that it did not precess, because by accident it seemed the whole sky rotated about the heliacal rising point of Sirius, which was at its northernmost turning point on the horizon. You can see what I mean by looking at the diagrams linked here. Happy to explain further.

[Alsor]

Hello Alsor, as it happens I have recently posted information that can help to correct your misconception (shared also by believers in a binary star theory) that observation of Sirius somehow disproves precession. The heliacal rising point of Sirius oscillates over the period of precession. At 1000 AD Sirius was at its furthest point from the South Celestial Pole, and so created the illusion that it did not precess, because by accident it seemed the whole sky rotated about the heliacal rising point of Sirius, which was at its northernmost turning point on the horizon. You can see what I mean by looking at the diagrams linked here. Happy to explain further.

I showed sufficient arguments that the precession of the axis is only a fiction borrowed from ancient mythology, the Bible / Koran, ect.

Sirius moves according to the orbital plane precession of Earth, which is about 5''/ year, but this is changing in a cycle of ~70 thousand years (Venus is close and has a comparable angular momentum and mass).
But the transits of Venus are undistorted over many centuries, so the precession of the orbits of both planets are simply cleverly synchronized.

Moment of inertia of the Earth is different - larger than this derived from hypothetical precession.

Chandler Wobble - this is the actual free precession of a slightly disturbed rotor (is constant, only the amplitude changes).

p = (1 - Ix / Iz) * W * cos (a) = const, a = ~ 90;
1 - Ix / Iz = 1 / 430;

for spheroid:
1 - Iz / Iz = 1 - b / a = f = 1 / 300;

Why so big difference?
Rotating mass is not actually a spheroid, but has a slightly different shape - more mass on the average latitudes.

[Garrison]

I
Moment of inertia of the Earth is different - larger than this derived from hypothetical precession

It is not hypothetical, as was pointed out earlier in the thread one of your own links provided one source of evidence. You have offered no cogent refutation of that evidence, or of any of the rest that has been offered to you.

Rotating mass is not actually a spheroid, but has a slightly different shape - more mass on the average latitudes.

If by rotating mass you mean the Earth then that is hardly news, there is a satellite mapping the variations as I write:

GOCE

Such variations are accounted for in model of the Earth's motion so what is your point in bringing it up?

[HenrikOlsen]

But the transits of Venus are undistorted over many centuries, so the precession of the orbits of both planets are simply cleverly synchronized.

The Venus transits are dependent on the position of Venus and the Earth relative to the Sun, they are not dependent on which direction its axis is pointing.

Why do you think precession of the axis would be involved?

[Alsor]

It is not hypothetical, as was pointed out earlier in the thread one of your own links provided one source of evidence. You have offered no cogent refutation of that evidence, or of any of the rest that has been offered to you.

I do not have to present arguments against the optical effects - that are common phenomena.

But I can hint about what's going on... maybe one day, and in another topic.

If by rotating mass you mean the Earth then that is hardly news, there is a satellite mapping the variations as I write:
GOCE
Such variations are accounted for in model of the Earth's motion so what is your point in bringing it up?

I say that the Chandler Wobble period is constant, which means that it is a free precession, and not forced (by a constant torque).

Thus, we can determine the ratio of moments of inertia: Ixy / Iz.
And it is clear that it does not fit the spheroid.
We also have a quadrupole moment of Earth: J2, and we know the radius: polar and equatorial.

From this we can calculate several important parameters of the Earth.

[Alsor]

The Venus transits are dependent on the position of Venous and the Earth relative to the Sun, they are not dependent on which direction its axis is pointing.

Why do you think precession of the axis would be involved?

Yes, but we also know the synodic period: 583.92 d, which is proportional to the orbital periods of both planets.
Increase both x times, and then the synodic period also increases x times.

583.92 days gives the Earth's orbital period = tropical year, no longer.

20.5 minutes times 250 years = 3.5 days.
You see, it is impossible - the days of transits are well known, and even hours.

[macaw]

I showed sufficient arguments that the precession of the axis is only a fiction borrowed from ancient mythology, the Bible / Koran, ect.

The precession is confirmed by observation.
No one used any of the holy books to claim the effect, quite the opposite, we have used observation.
Your calculations, on the other hand, have been proven: a) incorrect and b)in disagreement with observation.

[HenrikOlsen]

Yes, but we also know the synodic period: 583.92 d, which is proportional to the orbital periods of both planets.
Increase both x times, and then the synodic period also increases x times.

583.92 days gives the Earth's orbital period = tropical year, no longer.

20.5 minutes times 250 years = 3.5 days.

583.92 d is proportional how? Do you even know what synodic period means? And how it relates to tropical year?
1/224.701 = 1/583.924 + 1/365.256. Simple. Easy. What are you confused about?

What does all this have to do with precession of the Earth's axis?
What is x?
Where did you get 20.5 minutes from?
Where did you get 250 years from?

You see, it is impossible - the days of transits are well known, and even hours.

The future transit times are know to the second. Because it uses a description of the solar system that is actually reflecting the actual solar system rather than some idealized construct thought up without reference to actual measurements.

[Alsor]

583.92 d is proportional how? Do you even know what synodic period means? And how it relates to tropical year?
1/224.701 = 1/583.924 + 1/365.256. Simple. Easy. What are you confused about?

Simple, easy, and never used.

You have dates of transits: 1761 - 1769, and 2004 - 2012
http://en.wikipedia.org/wiki/Transit_of_Venus

So calculate the time between transits of 1761 and 2004, and then the synodic period, and check if it matches the second of the pair - in 2012 and 1769 respectively.

[HenrikOlsen]

1761 June 6
5 synodic periods, ~2920 days
1769 June 3–4
66 synodic periods, ~38538 days
1874 December 9
5 synodic periods, ~2920 days
1882 December 6
76 synodic periods, ~44379 days
2004 June 8
5 synodic periods, ~2920 days
2012 June 6

In both the pairs you mentioned, it's about 88756 days or 152 synodic periods. Using just the days, this gives a synodic period of 583.92 which is also the mainstream value to within the uncertainty caused by using whole days instead of the precise times.

I didn't bother to use the precise times of the transits because it's fairly obvious that there are no problems, definitely not on the scale of 3.5 days.

Now tell us where you got the 20.5 minutes from and 250 years from, I see those numbers nowhere.
And next time, please show your own calculations first rather than making me waste my time confirming the mainstream.

And tell me what all this has to do with the precession of the Earth's axis?

[Alsor]

In both the pairs you mentioned, it's about 88756 days or 152 synodic periods. Using just the days, this gives a synodic period of 583.92 which is also the mainstream value to within the uncertainty caused by using whole days instead of the precise times.

I didn't bother to use the precise times of the transits because it's fairly obvious that there are no problems, definitely not on the scale of 3.5 days.

Now tell us where you got the 20.5 minutes from and 250 years from, I see those numbers nowhere.
And next time, please show your own calculations first rather than making me waste my time confirming the mainstream.

And tell me what all this has to do with the precession of the Earth's axis?

584.92 d - the correct synodic period (with an error less than 1 minute).

Because there is no precession of the Earth's axis (is physically impossible):
Earth orbital period = 365.2422 d
Venus-Earth synodic = 583.92 d
Venus orbital period: 1/(1/583.92 + 1/365.2422) = 224.6952 d;

5 : 8 : 13 (synodic : Earth : Venus)

Pentagram rotation (backward):
5 * 583.92 / 365.2422 = 7.9936;
8 - 7.9936 = 0.0064;
0.0064 / 8 = 0.0008; (per 1 y).

0.0008 * 250 = 0.2 = 1/5;
Pentagram rotates 72 degrees per 250 years.

[HenrikOlsen]

Venus orbital period 224.701d, problem go boom.

[macaw]

Because there is no precession of the Earth's axis (is physically impossible).

Why do you keep repeating falsities that have already been refuted (both by calculation and, more importantly, by observation)?

[Garrison]

Because there is no precession of the Earth's axis (is physically impossible):

Now you might just be able to make a case, if you had the proper evidence and theoretical model, that the Earth doesn't have any procession(and lets be clear so far you have failed to do so). To claim it is impossible however is taking things to another level. Please explain what in mainstream physics rules out precession?

[grapes]

584.92 d - the correct synodic period (with an error less than 1 minute).

Because there is no precession of the Earth's axis (is physically impossible):
Earth orbital period = 365.2422 d
Venus-Earth synodic = 583.92 d
Venus orbital period: 1/(1/583.92 + 1/365.2422) = 224.6952 d;

As Henrik points out, the Venus orbital period is usually taken to be 224.70069 d, why do you insist on the different value?

[HenrikOlsen]

As Henrik points out, the Venus orbital period is usually taken to be 224.70069 d, why do you insist on the different value?

He's using the tropical/Gregorian year of 365.2422 days rather than the sidereal year of 365.256 days to calculate the sidereal period of Venus, which is why he's getting it wrong.

[Alsor]

As Henrik points out, the Venus orbital period is usually taken to be 224.70069 d, why do you insist on the different value?

This is a fictitious period calculated from the model of the lunisolar precession (in force only since 2000 - JPL2000).

The valid period is shorter minutes.
http://en.wikipedia.org/wiki/Transit...ury_from_Venus
"orbital period of Venus (224.695434 days)."


5 T = 5 * 583.92 = 252,253,440 s

06/08/2004 8:20 - 06/06/2012 1:29 = 252263340 s

difference: +9900 = 5 * 1980 s

06/08/2004 8:19 ​​- 06/06/1761 5:19 = 7668529200 s

152 T = 7668504576
difference: +24624 = 152 * 162s
-------

152 synodic periods, with a deviation 162 s (per 1 cycle).
The next 5, and the deviation 1980s!

These older dates are probably wrong - calculated from the theory, not recorded in practice.
In 2012, the transit should be earlier than 2 hours (8 * 20 min = 2 hours and 40 minutes).

It is better to use the cycles of the Moon - there errors grow more than 12 times faster, so just check a few decades.
20 minutes per year in the lunar orbit is very high.

[HenrikOlsen]

Every date I mentioned was observed directly by people. With watches. Please stop rejecting reality when it doesn't fit your preconceived ideas.

The 224.695434 days is the tropical period of Venus, it's the sidereal period of 224.70069 days that should be used. This is the value the rest of us has been using.
The Mercury-Venus transit page uses tropical orbital periods for both Mercury and Venus which is just plain wrong.

[grapes]

This is a fictitious period calculated from the model of the lunisolar precession (in force only since 2000 - JPL2000).

Interesting! This NASA/JPL website about Venus lists its sidereal orbital period as .61519726 "earth years."

If you multiply that by the earth tropical year, which the NASA site clearly calls an "earth year", since it lists the earth sidereal year as "1.0000174 earth years," you get the smaller value for Venus.

[Garrison]

These older dates are probably wrong - calculated from the theory, not recorded in practice.
In 2012, the transit should be earlier than 2 hours (8 * 20 min = 2 hours and 40 minutes).

It's already been explained that precession has been measured not simply predicted, on what basis do you continue to ignore this evidence?

ETA: And are you going to answer my question from post #80?

[Alsor]

Now you might just be able to make a case, if you had the proper evidence and theoretical model, that the Earth doesn't have any procession(and lets be clear so far you have failed to do so). To claim it is impossible however is taking things to another level. Please explain what in mainstream physics rules out precession?

1. The correct calculation must take into account the tidal deformations.

2. They are observed - up to 60 cm at the equator, exactly as much as needed.

3. Gravitational equilibrium = equipotential surface (not necessarily perfectly and permanently, just an average over time - no evolution).

4. Formal proof zero torque on the mass in equilibrium remains in force.

[Alsor]

It's already been explained that precession has been measured not simply predicted, on what basis do you continue to ignore this evidence?

'Precession' of the equinoxes was measured, not the axis.

[Garrison]

1. The correct calculation must take into account the tidal deformations.

2. They are observed - up to 60 cm at the equator, exactly as much as needed.

3. Gravitational equilibrium = equipotential surface (not necessarily perfectly and permanently, just an average over time - no evolution).

4. Formal proof zero torque on the mass in equilibrium remains in force.

I'm not seeing any citations or evidence there, just more of your claims.

[Garrison]

'Precession' of the equinoxes was measured, not the axis.

Different names for the same thing as explained here:

http://en.wikipedia.org/wiki/Precess...e_equinoxes.29

So effectively you are stating they did measure precession of the axis.