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Thread: Moon movements.!!!

  1. #31
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    Quote Originally Posted by sadang View Post
    Timmy, in your first animation, the Moon is not rotating around its own axial center of rotation wrt the center of revolving (or to any point internal to the circle of revolution of the Moon), but it SEEMS to have its own axial rotation wrt the Sun (or to any point external to the circle of revolution of the Moon). So, in the Earth-Moon system, I clearly sustain that the Moon does not have its own axial rotation movement. I also sustain, that outside of the same Earth-Moon system, the Moon has ONLY an APPARENT, not a REAL own axial rotation movement.

    - 1919 - Electrical Experimenter - Nikola Tesla - Famous Scientific Illusions
    - 1919 - Electrical Experimenter - Nikola Tesla - Moon's Rotation

    I invite everyone who understand what is general relativity, and can analyze the motion of an object in different reference systems, and to expose the arguments for or against those supported by me.
    My bold. What is your definition of "real"?

    I stand by my remarks in post #6. In my opinion you are giving us an example of the quibbling with words that I mentioned there. The Moon is clearly undergoing a compound motion as reckoned in a frame of reference in which the background stars are virtually stationary. I find no mathematical fault in describing this motion as a vector sum of a rotation of the Moon about its center combined with a translation of that center along an approximately elliptical orbit.

  2. #32
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    I suppose I might as well add my question for sadang:

    What distinguishes axial rotation from rotation which is
    not axial?

    -- Jeff, in Minneapolis
    http://www.FreeMars.org/jeff/

    "I find astronomy very interesting, but I wouldn't if I thought we
    were just going to sit here and look." -- "Van Rijn"

    "The other planets? Well, they just happen to be there, but the
    point of rockets is to explore them!" -- Kai Yeves

  3. #33
    @Jens
    The bicycle wheel will rotate in both cases, in your hand and going on the ground. In both cases we can say that it has its own axial rotation. But I think it is not the same case as with the Moon.

    @Timmy
    Yes, I totally agree! It rotates and has its OWN angular momentum (i wrote with caps look font because we know that there can be two kind of angular momentum; rotating/spin angular momentum and revolution/orbital angular momentum, or with other words, rotating/spin angular momentum is permanently wrt an external - to its own physical body - point of reference, and revolution/orbital angular momentum could be wrt to an external - to the circle/elliptic of revolution/orbiting - point of reference or wrt to the center of rotation/spin/symmetry/gravity/mass...depending on each case in part).

    @Hornblower
    I read your post no.6, and I agree with you, the Moon continuously changes the direction it is facing with respect to the fixed stars as it goes around its orbit. But fixed stars represent an external (see the above explanations) point of reference to the cirecle of revolution of the Moon. And now, because in the case of any object orbiting around a something else, there will always exists two point of references, one internal and other external to the circle/ellipse of revolution, tell me please how you see the Moon angular momentum wrt to the any internal point of reference (more easier wrt to the center of rotation)

    @Jeff Root
    Own axial rotation, is a term that I use instead of spin rotation, because someone caught my attention that the spin is used only at the quantum level. But of course, we can agree, here on this forum, to use spin rotation. I do not mind the conventions and the words used. I only care to understand how things are with our Moon. It is as I say, or I have gone crazy?

  4. #34
    Quote Originally Posted by sadang View Post
    @Jens
    The bicycle wheel will rotate in both cases, in your hand and going on the ground. In both cases we can say that it has its own axial rotation. But I think it is not the same case as with the Moon.
    In a sense, it is the same case though. Suppose that we look at the moon from a vantage point on the sun. What would we see? I think basically what you would see is this: you would see the moon going forward in one direction, though it would isolate nearer and closer to you, and the speed would get faster and slower at times. And you would see it slowly rotating so that you would see all its faces from time to time.
    As above, so below

  5. #35
    Quote Originally Posted by sadang View Post
    And now, because in the case of any object orbiting around a something else, there will always exists two point of references, one internal and other external to the circle/ellipse of revolution, tell me please how you see the Moon angular momentum wrt to the any internal point of reference (more easier wrt to the center of rotation)
    I know this question wasn't addressed to me, but sort of as a follow-up, because you mentioned the fixed stars. How about a Foucault pendulum. Do you think it would work on the moon?
    As above, so below

  6. #36
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    Quote Originally Posted by Jens View Post
    I know this question wasn't addressed to me, but sort of as a follow-up, because you mentioned the fixed stars. How about a Foucault pendulum. Do you think it would work on the moon?
    What a great idea! If we build a polar colony on the Moon, also build a huge Foucault pendulum on the pole! Line the swinging up with the direction to the Sun. It will make a revolution every 28 days, that's 56 little chess pieces in a circle around the low point of the swing to knock over at 2 per day. The colonists will waste more time watching the pendulum swing sooo slowly at 1/6 g than we waste playing solitaire on Windows.

  7. #37
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    Quote Originally Posted by P Timmy View Post
    In the animation below... do you agree that the object in the center is rotating on an internal axis and has angular momentum?
    Quote Originally Posted by sadang View Post
    Yes, I totally agree! It rotates and has its OWN angular momentum
    The objects in the animation are interchangeable. The object in the center is rotating while in a stationary position... and the other object is rotating while revolving around the center object. You agree that the object in the center is rotating and has angular momentum... so why would the object in the center not have that angular momentum just because it was in orbit?


  8. #38
    @Jens
    Yes, you are right. We, from Sun or from any other point of reference external to circle/ellipse of revolution/orbit of the Moon around the Earth, will see all faces of the Moon on the duration of a complete revolution. But this happens due to the Moon consecutive placement on the revolution/orbit path around the Earth, not due to the Moon's spin rotation.

    Let's make a short analysis of the cases when we can not see all faces of an object that revolve:
    1 - from a external, fixed or moving point of view (internal to the circle/ellipse of rotation - any other kind of movement except the rotation motion with the same revolution/orbital angular speed, around the same center of rotation like of the object revolving):
    a - when the object is revolving around a center of rotation/symmetry/mass and has no spin rotation - false
    b - when the object is revolving around a center of rotation/symmetry/mass and has spin rotation - false

    2 - from an internal, fixed or moving point of view (internal to the circle/ellipse of rotation)
    a - when the object is revolving around a center of rotation/symmetry/mass and has no spin rotation - true
    b - when the object is revolving around a center of rotation/symmetry/mass and has spin rotation - false

    From this short analysis we can see the single point of view from which we con not see all faces of the object is point "a" from second case, namely, "when the object is revolving around a center of rotation/symmetry/mass and has no spin rotation". Do you consider that there is something wrong in my reasoning? If yes, please argue here!

    In connection with the Foucault's pendulum, because I consider that the Moon has no spin rotation, I suppose it will not working in proper manner. It will not work!

    @John Mendenhall
    Great and nice imagination! I like your description. And of course, your triky suggestion! Even I am not sure if Foucault pendulum is a right instrument to indicate the Earth spin rotation (Decrypting the Eclipse - A Solar Eclipse, Global Measurements and a Mystery), let's make a short analysis about the movement of the Foucault pendulum in two cases when it is on the Moon's pole:
    1. - wrt the Sun
    If the pendulum will start swinging lined up with the Sun, after 24 hours, when the Moon will move on the orbit with a specific distance from the initial point of start, the pendulum will indicate on the same initial direction, will swing following permanently the same path, that means it will have a 0 degree deviation to the initial point of swinging. Not imagine that the pendulum will permanently follow the relatively fixed position of the Sun, and will divide the Moon into 56 slices. In conclusion, the pendulum will maintain the same direction of swinging wrt the Moon, but will apparently change its direction of swinging wrt to the Sun, due to Moon's orbital motion. So, after 7, 14, 21 and 28 days the pendulum will swing on the same direction wrt the Moon, but its swinging line will make a 90, 180, 270 and 360 degrees wrt the Sun.
    2. - wrt the Earth
    If the pendulum will start swinging lined up with the Earth, after 24 hours, when the Moon will move on the orbit with a specific distance from the initial point of start, the pendulum will indicate on the same initial direction, will swing following permanently the same path, that means it will have a 0 degree deviation to the initial point of swinging. Not imagine that the pendulum will permanently follow the relatively fixed position of the Earth, and will divide the Moon into 56 slices. In conclusion, the pendulum will maintain the same direction of swinging wrt the Moon, and will not change its direction of swinging wrt to the Earth, on its orbital motion. So, after 7, 14, 21 and 28 days the pendulum will swing on the same direction wrt the Moon, and will maintain the same 0 degree for the swinging line wrt the Earth.

    @Timmy
    That two objects are interchangeable just like objects, not like their own separate movements. Let's take the example of a bicycle wheel:


    If the wheel rotate, the flag on this wheel, will make a 360 degree rotation around the central axis of rotation of the wheel, not around its own axis of rotation/spin. This is the case in your animation. You can say about that flag that it has a 360 degree rotation around its own axis, over a period of a complete rotation of the wheel? I think you can't!

    Now, concrete to your animation.
    1. If you translate the central object to a distance at least twice at its own diameter, you wiil transform the spinning object in a revolving object, which will revolve around the central point of origin/rotation/symmetry, transforming its spin rotation in consecutive placement of the object on the curved orbital path. The speed of revolving will be in a certain report with the initial spin motion.
    2. If you translate the orbiting object to its center of revolution/orbit/rotation, will transform the revolving object in a spinning object, having a spinning speed in a certain report with the initial revolving speed.

    I am not sure if this is an correct explanation, because, after all this analysis of rotational motion from different points of reference, my brain is already spinning, along with all my ideas!

  9. #39
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    Quote Originally Posted by sadang View Post
    So, in the Earth-Moon system, I clearly sustain that the Moon does not have its own axial rotation movement. I also sustain, that outside of the same Earth-Moon system, the Moon has ONLY an APPARENT, not a REAL own axial rotation movement.
    Welcome to the discussion group, sadang.

    The Moon is rotating about its axis. The Earth is rotating about its axis. Both the Earth and Moon are revolving around their common barycenter. The Earth-Moon barycenter revolves around the Sun.

    As an astronaut remaining on the surface of the Moon, you would see the Sun and stars rise, traverse the sky, and set. Only the Earth would appear to remain near the same spot in your lunar horizontal coordinate system for the sky. There is a slight bulge at the lunar equator relative to its rotational axis. This implies a true inertial rotation about its axis.
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  10. #40
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    Quote Originally Posted by sadang View Post
    @Timmy
    That two objects are interchangeable just like objects, not like their own separate movements.
    Well how about this:::

    Imagine a "top" (a child's toy... gif below) spinning. Sometimes these toys spin while in a stationary position... and sometimes they move in a straight line or a circle while they continue to spin. I think you agree that the toy has angular momentum while spinning in a stationary position... but what if the toy begins to move in a circle as it continues to spin... wouldn't it still have angular momentum?

    Last edited by P Timmy; 2012-May-16 at 10:37 PM.

  11. #41
    Quote Originally Posted by sadang View Post
    @Jens
    Yes, you are right. We, from Sun or from any other point of reference external to circle/ellipse of revolution/orbit of the Moon around the Earth, will see all faces of the Moon on the duration of a complete revolution. But this happens due to the Moon consecutive placement on the revolution/orbit path around the Earth, not due to the Moon's spin rotation.
    What if the moon was orbiting around the earth, but was moving in such a way that if you looked from the sun, you would always see the same face of the moon? (In this case, an observer on earth would see the moon rotate once every 30 days). In that case, would you say the moon is rotating?
    As above, so below

  12. #42
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    Thanks for the links to articles by one of my favorite scientists! They are archetypically teslian!

    In the next to last paragraph of the second article he says:
    As I have shown before, a ball flying off will rotate at the rate of the wheel and in the same direction.
    So he's actually done the experiment, but he still denies it! How unbelievably quirky!

    He even allows that a Foucault pendulum on the moon would show rotation. And still denies that the moon possesses rotational momentum. Weird.

  13. #43
    @Centaur
    Thanks for wishes!

    I would have liked to be an astronaut .... but ... maybe next time! As an astronaut left on the Moon, I will see, indeed, stars spinning around me over a period of ~28 days, and the Earth remaining permanently near the same spot, but this is due to movement of revolution of the Moon, not because its spin motion.

    In connection with its slight bulge at the Moon equator, this small difference of about 2Km between equatorial and polar radius, I think it is not a result of an axial rotation (centrifugal force or/and tidal bulge). And if we consider the real center of mass, displaced with about 1,8Km towards the Earth, and also that the higher bulge is on the far side of the Moon, I think the true inertial rotation about its own axis, became a really strange argument. Bellow is an image with a cross section of the Moon:


    And more info about these aspects can be found here:
    - Lunar Reconnaissance Orbiter Camera

    @Timmy
    In the case of a top toy, it will have initially a high speed spin rotation (a great angular speed), when it is in a stationary position, and after a while, when it start to move in circles, it will have both, revolving angular speed, and a spin angular momentum. But this toy rotation, is not similar to the Moon's rotation, because we can see all faces of this toy, when it rotate in a stationary position, and also, when it move in circles, even if we look at it form the internal circle of rotation or from its external circle of revolution.

    I do not want to upset anyone, but I consider naturally, ad of common sense, that an object has its own axial rotation movement only when it actually rotates, whether static or in motion of revolution or rotating around something physical, or just around a simple rotation center. This means that me, located within the circle of rotation can see all faces of that object orbiting around me, over a period of time longer or shorter, directly related to its own angular momentum speed.

    @Jens
    Yes, in this case the Moon will rotate wrt any point of reference internal to its circle/ellipse of orbit/revolution, but will not rotate wrt the Sun, or any other point of reference external to the same circle/ellipse of orbit/revolution.It is a weird result, but this is the reality. Try yourself, with three apples and make with them the Moon, Earth and Sun:
    1 - rotate the Moon around the Earth with a fixed face towards the Earth, and will observe the Moon will rotate wrt the Sun (will show all faces to the Sun).
    2 - rotate the Moon around the earth with a fixed face towards the Sun and will see that the Moon will rotate wrt the Earth (will show all faces to the Earth).

    @grapes
    I like to see that you are the first who indeed read the articles of Tesla. I appreciate this, because I give more credit to Tesla than to the actual science. But, of course, this is just my point of view, and should be considered only in this form. I am a guy with an open mind, without preconceptions or dogma, and who analyze a phenomenon on all sides, from all points of view.

    This statement of Tesla, noticed by you
    As I have shown before, a ball flying off will rotate at the rate of the wheel and in the same direction.
    have to be corroborated together with this one
    There is no true analogy to these in the motion of the moon. If the gravitational string, as it were, would snap, the satellite would go off in a tangent without the slightest swerving or rotation, for there is no moment about the axis and, consequently, no tendency whatever to spinning motion.
    Related to what Tesla said about Foucault pendulum...
    Even the wellknown experiment with the Foucault pendulum, altho exhibiting similar phenomena as on our globe, would merely demonstrate a motion of the satellite about some axis. The view I have advanced is NOT BASED ON A THEORY but on facts demonstrable by experiment. It is not a matter of definition as some would have it. A MASS REVOLVING ON ITS AXIS MUST BE POSEST OF MOMENTUM. If it has none, there is no axial rotation, all appearances to the contrary notwithstanding.
    I am not sure at what phenomena he make references in his assertion that "... altho exhibiting similar phenomena as on our globe...", but what is clear for me is what he say next, namely, "[i]... would merely demonstrate a motion of the satellite about some axis...". From this phrase is evident that he referes to some other axis of rotation, like that of revolution around the Earth, or around the Sun, or around the galactic center, or... any other kind of exis of rotation, not only to the Moon's axial spinning axis.

    At least, this is what I undestand from those written by Tesla. If you understand other way, and consider that I am wrong in my understandings, please post here your point of view and will try togheter, or with help from others, to find the real sense of what Tesla claim in his articles.

  14. #44
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    Quote Originally Posted by sadang View Post
    At least, this is what I undestand from those written by Tesla. If you understand other way, and consider that I am wrong in my understandings, please post here your point of view and will try togheter, or with help from others, to find the real sense of what Tesla claim in his articles.
    Clearly, Tesla knew what to do, and how to do it. And, unlike most, he actually did it, apparently. He just couldn't reconcile it in his head. Truly, a beautifully crazy person.

  15. #45
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    sadang
    In the case of a top toy, it will have initially a high speed spin rotation (a great angular speed), when it is in a stationary position, and after a while, when it start to move in circles, it will have both, revolving angular speed, and a spin angular momentum.
    Yes... the top has rotational momentum whether its rotating in a stationary position or rotating while moving in a circle.
    And whether stationary or moving in a circle... the top would have rotational momentum even if it was rotating only once every 27.3 days.

    The objects below are spinning tops and both are spinning one time every 27.3 days... don't you agree that both have rotational momentum?


  16. #46
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    Quote Originally Posted by sadang View Post
    As an astronaut left on the Moon, I will see, indeed, stars spinning around me over a period of ~28 days, and the Earth remaining permanently near the same spot, but this is due to movement of revolution of the Moon, not because its spin motion.

    Please read my post #25 in this thread. If you were located far north of the solar system yet were blind to the Earth, you would see the Moon revolving around the Sun in a continuously concave orbit, unlike all other planetary satellites. At the same time you would see the Moon rotating on its axis. Simply because the Moon's originally shorter rotation period eventually increased to 27.32 days, does not mean the rotation stopped. I would be dumbfounded if a Foucault pendulum could not prove this. If you agree this is all so, yet still want to claim the Moon is not rotating, then we are dealing with semantics and you are out on a limb by yourself.
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  17. #47
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    To Sadang
    According to you... the doll in the center makes two real rotations during the time it takes the doll in orbit to make a complete revolution... and the doll in orbit rotates two times per revolution but only one of those rotations is real and the other rotation is only apparent.

    As to the doll in orbit... which of its rotations is real... the first one it makes... or the second one it makes?


  18. #48
    @Timmy
    1'st post - I don't agree. The central top indeed, have angular momentum, but the revolving top don't have any angular momentum. The revolving top is like a top that revolve in a circle without having spinning speed. An impossibility!

    2'nd post - In second animation, you exposed correctly the rotation of both dolls. Let's make the analysis of each one doll separately:
    1. - central doll
    1.a - from any external POV
    - make two real axial rotations over e period of complete revolution of the orbiting doll. That means we can see two real rotation around its own axis, from any external point of reference, from anywhere in the universe.
    1.b - from any internal POV
    - nor applicable

    2. - orbiting doll
    2.a - from any external POV
    - it will make two rotations around its own axis over a complete revolution time.
    2.b - from any internal POV
    - it will make a single rotation around its own axis over a complete revolution time.

    Now, from your comment
    ... and the doll in orbit rotates two times per revolution but only one of those rotations is real and the other rotation is only apparent...
    I see that you consider the movement of the orbiting doll only from external point of view (external to the circle of revolution). Maybe I am wrong, but this is what I understand from your phrase

    But now, make an exercise of imagination, and look at the movement of the orbiting doll, from any internal point of view (internal to the circle of revolution). From this poin you will see only a single rotation around its own axis of the orbiting doll over a complete revolving movement. Look closely, and tell me if I am right or wrong?

    And to answer to your question, I can only say that I don't know which answer is the correct one: two axial rotations seen from any external POV or one axial rotation seen from any internal POV! This is the big question! Why is this difference, if my reasoning is correct? Or maybe is not right and if you notice where I'm wrong, please show me!

    @Centaur
    I do not want, to get me wrong. From articles of Tesla and in what I read on the net and from my personal library, I do not clear at all, why the science says the Moon own axial rotation is synchronous with that of the revolution, when it seems to me obvious that the Moon does not rotate around its own axis.

    On the other hand, I'm not trying to convince anyone of anything, but, I am trying to explain myself, this dichotomy, which represents the existence or not of the Moon's own axial rotation, analyzed from two points of view, internal and external of the circle of revolution.

    Returning to you last message, I would not want to debate in this topic the rotation of the Moon around the Sun, because I did it on another forum, and we will contradict more, and will dilute the actual theme of topic. My short answer is: I don't agree with the Moon rotation around the Sun. Let's resume only at the Moon's axial rotation!

    Your statement
    "Simply because the Moon's originally shorter rotation period eventually increased to 27.32 days, does not mean the rotation stopped"
    it is only a working hypothesis, and not a relative or absolute truth!. Neither Newton nor anyone else ever since can not say with certainty how the Moon formed, or who initially gave the impulse for the rotation of celestial bodies. This represents just one of many absolutes hypothetical work, expressed in Newton's axioms expressed in "Philosophić Naturalis Principia Mathematica", and which is based the whole his gravitational theory.

    Also, to this rhetorical interrogation,
    "...does not mean the rotation stopped. I would be dumbfounded if a Foucault pendulum could not prove this..."
    I can not answer, other than with another rhetorical interrogation statement: "I would be dumbfounded if a Foucault pendulum could prove this!".

  19. #49
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    Quote Originally Posted by sadang View Post
    I can not answer, other than with another rhetorical interrogation statement: "I would be dumbfounded if a Foucault pendulum could prove this!"
    Actually, I think Tesla concedes that a Foucault pendulum on the moon would show rotation. Tesla's error is in not breaking down the math far enough--not one of his strong points.

    I'll see if I can find the quote in that paper.

    ETA: OK, second paper, second page, first few lines:
    Even the well-known experiment with the Foucault pendulum, altho exhibiting similar phenomenon as on our globe, would merely demonstrate motion of the satellite about some axis.

  20. #50
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    Quote Originally Posted by sadang View Post
    ...when it seems to me obvious that the Moon does not rotate around its own axis.
    The Moon's rotation rate is virtually constant as though it were clockwork. It's angular speed of revolution relative to the Earth varies due to the eccentricity of its orbit. This causes the Earth not to appear at a fixed location in the lunar sky, but produces an apparent monthly oscillation. Earthbound observers see this as a libration of the Moon's surface. Due to the interaction of Earth's orbit around the Sun and the Moon's orbit around the Earth, as viewed from Earth the Moon does not align itself with a particular star in exactly the same period of time from month to month. But a particular star crosses a lunar observers meridian every 27.321662 days precisely. Therefore the Moon's rotation rate and revolution rate are not constantly in perfect sync. It is only after a long period of time that the rates average to the same value. The Moon has an inertial rotation about its axis. I can't imagine why you so adamantly want to dispute this.
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  21. #51
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    Quote Originally Posted by sadang View Post
    And to answer to your question, I can only say that I don't know which answer is the correct one: two axial rotations seen from any external POV or one axial rotation seen from any internal POV! This is the big question! Why is this difference, if my reasoning is correct? Or maybe is not right and if you notice where I'm wrong, please show me!
    sadang,

    Let me make this VERY clear. As long as you really are "just asking", so as to understand the mainstream physics, then this conversation may continue. But you may not cross the line into advocating a non-mainstream idea (such as the moon doesn't rotate); that may ONLY be done in the ATM forum. Consider that an official warning. If you violate this, you will be infracted.
    At night the stars put on a show for free (Carole King)

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  22. #52
    @grapes
    I already answered to your last message, in my previous message. I will insert here, using quotes the entire explanations given there. here it is:
    Related to what Tesla said about Foucault pendulum...
    Even the wellknown experiment with the Foucault pendulum, altho exhibiting similar phenomena as on our globe, would merely demonstrate a motion of the satellite about some axis. The view I have advanced is NOT BASED ON A THEORY but on facts demonstrable by experiment. It is not a matter of definition as some would have it. A MASS REVOLVING ON ITS AXIS MUST BE POSEST OF MOMENTUM. If it has none, there is no axial rotation, all appearances to the contrary notwithstanding.
    I am not sure at what phenomena he make references in his assertion that "... altho exhibiting similar phenomena as on our globe...", but what is clear for me is what he say next, namely, "... would merely demonstrate a motion of the satellite about some axis...". From this phrase is evident that he referes to some other axis of rotation, like that of revolution around the Earth, or around the Sun, or around the galactic center, or... any other kind of exis of rotation, not only to the Moon's axial spinning axis.

    At least, this is what I understand from those written by Tesla. If you understand other way, and consider that I am wrong in my understandings, please post here your point of view and will try together, or with help from others, to find the real sense of what Tesla claim in his articles.
    @Centaur
    The synchronicity to which I referred in the previous message, is described on wikipedia, that is, ...The Moon is in synchronous rotation: it rotates about its axis in about the same time it takes to orbit the Earth.. And your explanation is more accurate, I understand it, I appreciate it, I agree with it, and thank you for it.

    But the libration movement of the Moon, as seen from Earth, and the fact that the Moon's rotation rate and revolution rate are not constantly in perfect sync, only after a long period of time, is not an explanation or proof of the Moon's own axial rotation.

    You ask why I want to dispute the Moon's axial rotation! Is very simple, because I don't want to accept something that I don't understand. And that is why I'm here, to understand. But not superficially, but to really understand, as deeper as is possible, the reality and the existence of its own axial rotation movements of the Moon.

    @Swift
    I really don't understand your intervention! What I did wrong? Or I have to ask, and accept any explanations as it is? Exactly like a robot! If I don't understand something, I consider natural to ask explanations, and to express my opinion, because of this I have a head over the shoulders and a brain in it.

    And what is an ATM forum?

    Anyway, I consider your behavior, as one of intimidation, or censorship or free speech and think. And if you really think I did something wrong, you can close my account or delete my posts, or just tell me not to post, and is enough!

  23. #53
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    Quote Originally Posted by sadang View Post
    @grapes
    I already answered to your last message, in my previous message.
    I was surprised when I first read that article to find Tesla agreeing with most of the objections to the argument. In other words, when people usually deny that the moon rotates, they also deny that a ball loosed from a whirling string would continue rotating, or they deny that a Foucault pendulum on the moon would show the rotation--but Tesla was too smart for that. He actually did the experiments. However, he was led astray by a simple error in math, one that any freshman engineer (OK, an engineer who has finished freshman year) would know to avoid.

    Tesla forgot to apply the parallel axis theorem. Stupid mistake.

    ETA: Speaking of stupid mistakes, I re-read that part of the paper and now I'm thinking that Tesla denies the parallel axis theorem, that it doesn't agree with his experiments! This is even more interesting. But, sorry about that.

  24. #54
    @grapes
    Tesla indeed, made the experiments weight whirled on a string or in a sling.. He studied the results and he concluded that it is not the same case as is for the Moon, as he stated in the second article:
    "There is no true analogy to these in the motion of the moon. If the gravitational string, as it were, would snap, the satellite would go off in a tangent without the slightest swerving or rotation, for there is no moment about the axis and, consequently, no tendency whatever to spinning motion."
    In this statement of Tesla, I underlined that phrases that I consider essential.
    - There is no true analogy to these in the motion of the moon - from this phrase he clearly disagree with the Moon's own axial rotation
    - gravitational string - using this phrase he clearly differentiate this kind of string apart from the above mentioned whirling string or sling.
    - for there is no moment about the axis - again he clearly maintain the assertion that the Moon has no own axial rotation motion.

    Conclusion - He consider the case of the Moon linked to Earth by "the gravitational string" a separate and totally different case, apart from a weight whirled by a string or a sling. He don't agree with these two often used analogies.

    Related to Foucault pendulum experiments, I repeat again what he wrote in his article: "... Even the wellknown experiment with the Foucault pendulum, altho exhibiting similar phenomena as on our globe, would merely demonstrate a motion of the satellite about some axis...". I also underlined the phrases that I consider relevant from his statement.
    Let's see:
    - altho exhibiting similar phenomena as on our globe - means it will display phenomena similar to those on Earth, not identical.
    - about some axis - means about some axis, any different external axis of rotation, not strictly about its center of mass, or it own rotational axis, or its center of symmetry, or its center of gravity.... For an object can exists an infinity of axis of rotation, even internal or external to its physical body limits.

    As we know for sure, a Foucault pendulum can only show the rotational movement of a physical body on it is placed, wrt an external point of reference. Always, wrt to an external point of reference. If the rotational motion does not exists, there will be just a swinging movement of the pendulum. As is the case of the Moon. This is what he finely is trying to suggests in that phrase. At least in my opinion!

    Conclusion - He did not consider the Moon to exhibits identical phenomena like on the Earth, but instead, he consider that the pendulum will exhibit no own axial rotation of the Moon.

    Now, related to the theorem of parallel axis, that you consider he missed in his analysis of Moon's rotation. This theorem has availability when the analyzed object has a really axis of rotation, and conclusively it really has an axial rotation. But, as we can see from his article's mathematical and experimental demonstrations, he proved that the Moon has no axial rotation, at all. The Moon has indeed, an axis of rotation, but this axis is external to its physical body, and is the axis of revolution/orbiting. This is the single axis of the Moon. And yes, now we can apply the theorem of two parallel axis, and can calculate the Iz.

    And do not forget an essential thing, any inertial momentum calculation is done in relation to something else, not with himself. In relation with other reference. In this specific case, we try to calculate the inertial moment of the new axis, parallel to first, starting this calculation from the premise that the first axis (Ix) has a real inertial moment. Wrong premises, wrong results!

    Conclusion: He did not apply the theorem of two parallel axis, because he did not consider it valid in the case of the Moon, not because he did not know it, or because it doesn't agree with his experiments!

    This is just my point of view, not an absolute truth. My arguments are not necessarily against those exposed by you, but my arguments just come to complete your arguments, according to what and how I understand what was written by Tesla.

  25. #55
    Quote Originally Posted by sadang View Post
    @grapes
    @Swift
    I really don't understand your intervention! What I did wrong? Or I have to ask, and accept any explanations as it is? Exactly like a robot! If I don't understand something, I consider natural to ask explanations, and to express my opinion, because of this I have a head over the shoulders and a brain in it.

    And what is an ATM forum?

    Anyway, I consider your behavior, as one of intimidation, or censorship or free speech and think. And if you really think I did something wrong, you can close my account or delete my posts, or just tell me not to post, and is enough!
    Read the rules for posting to the Forum, they are linked at the bottom of this post. Asking questions is OK as long as that is all you are doing. IF you get mainstream answers to a question but then dispute them and advocate your own, or someone elses ideas that are against the mainstream of science it must be done in the ATM Forum. Please take some time to read the rules for posting to the board, they are linked at the bottom of this post.
    Please do not argue or dispute Moderator actions ina thread, it is disruptive, if you have a disagreement then use the reporting triangle at the bottom left corner of the post and report it to the moderation team.

    Nobody is censoring you or disputing your 'free speech' the Internet is full of places for you to advocate any idea you want. On this board there are certain rules that go with this advocacy and certain places that it is allowed.

    Thank you
    Rules For Posting To This Board
    All Moderation in Purple

  26. #56
    @captain swoop
    Thank you very much for this clear explanations. I read the forum rules and I consider that are very restrictive. Just seems to be a forum that respects free speech and thinking, in reality is censored any deviation from the current scientific rules. Just like in the joke with monkeys and bananas that can be read here: Monkeys and bananas!. I ask all those reading this post to ask himself: With which monkey, I can identify? And the fundamental question, why ? I am really disappointed to still see this kind of behavior in the actual stage of e(in)volution of humanity. Really disappointed!

    So, my decision is to stop posting here, on this topic and also on this forum, because in my analysis of the Moon's movements, I will have to go to the basis of gravitational theory, to the premises on which it was based, to all those Newton's axiomatic defined absolutes described in his Principia, and in this case I can not understand how someone could take the decision of what is right or wrong.

    @All
    Sorry for my intervention inopportune, and for daring to put all those uncomfortable questions, but if I have caused as little curiosity, always look for answers by yourself, always beyond appearances, even if for that you have to turn the world upside down! Thank you for supporting me and success on the road of knowledge.

  27. #57
    Join Date
    May 2005
    Posts
    5,443
    Quote Originally Posted by sadang View Post
    - altho exhibiting similar phenomena as on our globe - means it will display phenomena similar to those on Earth, not identical.
    Of course it won't be identical, the moon rotates once per month, the earth once per day.
    Conclusion - He did not consider the Moon to exhibits identical phenomena like on the Earth, but instead, he consider that the pendulum will exhibit no own axial rotation of the Moon.
    No he said it would exhibit similar behavior--in referring to it aligning with outside references.

    Conclusion: He did not apply the theorem of two parallel axis, because he did not consider it valid in the case of the Moon, not because he did not know it, or because it doesn't agree with his experiments!
    He says it's not appropriate for the moon because it's not appropriate for the experiments!

    The whole article depends upon a simple experiment that is done in a freshman lab! This is incredible! How in the world did he screw that up?

  28. #58
    Join Date
    Dec 2004
    Posts
    12,195
    Sadang,

    I think it is too bad that you choose to run away when
    faced with a daunting task of your own making. You
    want to convince other people that your goofy ideas
    about rotation are right, but you aren't willing to do
    the work required to convince anyone. All you end up
    doing is demonstrate that, like Tesla, your knowledge
    of physics and your beliefs about physics conflict with
    each other.

    I repeat: The person for you to converse with is
    Gerald Kelleher, also known online as Oriel36. He is
    the one guy you want to talk to.

    -- Jeff, in Minneapolis
    http://www.FreeMars.org/jeff/

    "I find astronomy very interesting, but I wouldn't if I thought we
    were just going to sit here and look." -- "Van Rijn"

    "The other planets? Well, they just happen to be there, but the
    point of rockets is to explore them!" -- Kai Yeves

  29. #59
    Join Date
    Mar 2012
    Posts
    355
    Quote Originally Posted by sadang View Post
    @captain swoop
    Thank you very much for this clear explanations.
    Yes... thank you for the clear and respectful explanation... and below is a link to advice for posting at ATM.

    http://www.bautforum.com/showthread....465#post352465

    Even though I read the rules before posting here... it now appears that I should have started this thread in the ATM area (link below)...

    http://www.bautforum.com/forumdispla...the-Mainstream

    and then there wouldn't have been any need to warn Sadang about infractions if he did break a rule in this thread. So I apologize for my part that lead up to Sadang choosing to leave. But how about moving this thread to ATM and maybe Sadang would come back... and those that choose to could continue on with what has been a very respectful thread with potential to come to a meeting of the minds?

  30. #60
    Join Date
    Jun 2002
    Posts
    13,000
    Quote Originally Posted by P Timmy View Post
    ...it now appears that I should have started this thread in the ATM area...
    Not at all. You were not advocating an ATM idea.


    ...how about moving this thread to ATM and maybe Sadang would come back...
    Since he finds the rules here, "restrictive", I doubt he would.

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