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Thread: Trojan

  1. #91
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    Quote Originally Posted by Dave Lee View Post
    In the same token, all the objects in the galaxy (including the Sun) must revolve around some center of mass.
    I have called it Trojan Point, you can call it primary point.
    A Trojan Point is not the center of mass of any bodies

    In general, objects do not orbit around centers of mass. Once you have more than two bodies, things get complicated. The center of mass of the earth-moon system is a long ways from the center of the earth, so clearly earth satellites do not orbit that center of mass.

    ETA: That's an extreme case, and you've already restricted it to bodies inside the orbit, but the effect of bodies outside the orbit can be ignored if they are a uniform spherical shell. That's not the case here, nor in the disk of the galaxy.
    Last edited by grapes; 2018-Jan-09 at 10:52 AM. Reason: Eta

  2. #92
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    Quote Originally Posted by AGN Fuel View Post
    That (simplified) diagram shows the orbit of the moon around the Sun (travelling in conjunction with the Earth, which is not shown). It does not represent any "up and down" motion equivalent to the bobbing motion of the sun as it passes up and down through the galactic plane. There is NO equivalence in your example.
    Why?
    It is absolutely Identical Sine wave.
    As I have stated, the only difference is in the amplitude and the rotation phase.
    Based on the following diagram:
    https://www.quora.com/Does-the-moon-...around-the-sun
    The rotation of the moon is Horizontal with regards to the Earth/Sun disc plane.
    Therefore it is moving in and out.
    I don't know what is the real orbital phase of the moon with regards to the Earth/Sun disc plane.
    If it is vertical, than the moon will go up and down.
    I assume that in reality, the moon is orbiting somewhere in between a perfect horizontal to a perfect vertical (as the sun does).

    So, the effects of the moon revolving around the Earth, while the Earth revolve around the sun is identical to the Sun which is revolving around its center of mass, while this one revolve around the center of the galaxy. In both revolving we should have by 100% same sine wave shape (except of amplitude and phase).
    Last edited by Dave Lee; 2018-Jan-09 at 11:14 AM.

  3. #93
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    Quote Originally Posted by grapes View Post
    In general, objects do not orbit around centers of mass. Once you have more than two bodies, things get complicated. The center of mass of the earth-moon system is a long ways from the center of the earth, so clearly earth satellites do not orbit that center of mass.

    Well, if I understand it correctly:
    The moon and the Earth are revolving around their common center of mass.
    Due to the difference in the total mass, this center of mass is located very close to the center of Earth.
    However, this center of mass revolving around the Sun.
    So, it is not the Earth which revolving around the Sun. In reality - it is the Virtual point which is represented by Earth/Moon center of mass

  4. #94
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    Quote Originally Posted by Strange View Post
    The galaxy is more complex, gravitationally.
    Fully agree

    Quote Originally Posted by Strange View Post
    It is not just a central point that the Sun orbits.
    The Sun revolve around its Center of mass.
    You can call it privary point. you can call it the Sum of all the vectors form the near by stars or mass. But there is a clear point which the Sun revolve around it.
    For this discussion, lets call it "point P".

    Quote Originally Posted by Strange View Post
    The Sun does orbit around the centre of the galaxy, in a roughly circular motion.
    It is not the Sun which orbits around the center of the galaxy it is "Point P".
    And yes, "point P" orbits in a roughly circular motion around the center of the galaxy.

    Quote Originally Posted by Strange View Post
    This is separate from its motion above and below the galactic disk, which is caused by the mass of the disk and this cannot be treated the same way as one body orbiting another.
    So, "Point P" is located at the galactic Disc.
    However, as the Sun orbits around this point, it is moving up and down, while "point P" orbits in a roughly circular motion around the center of the galaxy.
    Last edited by Dave Lee; 2018-Jan-09 at 11:44 AM.

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    Quote Originally Posted by Dave Lee View Post
    The Sun revolve around its Center of mass.
    You can call it privary point. you can call it the Sum of all the vectors form the near by stars or mass. But there is a clear point which the Sun revolve around it.
    For this discussion, lets call it "point P".
    That would be the centre of the galaxy. If you think it isn't, then please show in mathematical detail where this Point P is and why.

    So, "Point P" is located at the galactic Disc.

    However, as the Sun orbits around this point, it is moving up and down, while "point P" orbits in a roughly circular motion around the center of the galaxy.
    Please prove this in suitable mathematical detail.

    Just repeatedly asserting something does not make it true.

  6. #96
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    Quote Originally Posted by Dave Lee View Post
    Sorry.
    There is no difference in the rolls between moon, planet or Star in the galaxy.
    There is no VIP in the system.
    If you want to be part of the galaxy, you must obey to the same rolls (even if we call you Star or Sun)!
    Just answer the question, please:
    Quote Originally Posted by grant hutchison View Post
    If we ignore your supposed explanation for the movement, your last line answers my question. (The combined motions you describe will actually result in a trochoidal curve, not a sinusoid.)

    So as the sun moves around the galaxy, it also goes up, stops moving upwards, and then comes down again.
    And as the ball in Jens's example moves from thrower to catcher, it also goes up, stops moving upwards, and then comes down again.

    Direct question: Do you agree with that?
    Grant Hutchison
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  7. #97
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    Quote Originally Posted by Dave Lee View Post
    Why?
    It is absolutely Identical Sine wave.
    As I have stated, the only difference is in the amplitude and the rotation phase.
    Actually, neither the moon's orbit around the Earth, nor the Sun's orbit around the galaxy, trace out a sine wave.

    By the way, are you aware that the described movement of the sun around the galaxy is a theoretical one? We haven't been around long enough to observe it.
    The bobbing motion you're so exercised about is based on a calculation, and the calculation is derived from exactly the gravitational mathematics we've all been telling you about, and which you claim can't produce the up and down motion.

    Quote Originally Posted by Dave Lee View Post
    The Sun revolve around its Center of mass.
    You can call it privary point. you can call it the Sum of all the vectors form the near by stars or mass. But there is a clear point which the Sun revolve around it.
    For this discussion, lets call it "point P".
    You can stop the discussion right there, because this is a false claim. As has already been pointed out to you repeatedly There is not a clear point around which the sun revolves. This misunderstanding underlies your whole argument.

    Grant Hutchison
    Last edited by grant hutchison; 2018-Jan-09 at 02:58 PM. Reason: clarity
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  8. #98
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    Quote Originally Posted by Dave Lee View Post
    Quote Originally Posted by grapes View Post
    In general, objects do not orbit around centers of mass. Once you have more than two bodies, things get complicated. The center of mass of the earth-moon system is a long ways from the center of the earth, so clearly earth satellites do not orbit that center of mass.

    Well, if I understand it correctly:
    The moon and the Earth are revolving around their common center of mass.
    Due to the difference in the total mass, this center of mass is located very close to the center of Earth.
    It is closer to the surface of the earth than to the center. It's approx the ratio between their relative distances divided by their relative masses, so it's about 3/4 of the radius of the earth. That's quite a ways away from the center of the earth.
    However, this center of mass revolving around the Sun.
    So, it is not the Earth which revolving around the Sun. In reality - it is the Virtual point which is represented by Earth/Moon center of mass
    Even if there were only the three bodies, sun, earth, and moon, the earth/moon center of mass would not follow a perfect ellipse around the sun.

    If you say the earth and moon are not revolving around the sun, then you have to say that their center of mass is also not. It's complicated, and you cannot simplify it in the way that you are trying to simplify it.

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    Quote Originally Posted by grapes View Post
    It is closer to the surface of the earth than to the center. It's approx the ratio between their relative distances divided by their relative masses, so it's about 3/4 of the radius of the earth. That's quite a ways away from the center of the earth.
    Even if there were only the three bodies, sun, earth, and moon, the earth/moon center of mass would not follow a perfect ellipse around the sun.
    If you say the earth and moon are not revolving around the sun, then you have to say that their center of mass is also not. It's complicated, and you cannot simplify it in the way that you are trying to simplify it.
    Thanks
    That is perfectly clear.

  10. #100
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    Quote Originally Posted by Reality Check View Post
    The Sun orbits around the center of mass of all of the stars within its orbit around the galaxy with an influence by the mass of stars outside of the orbit.
    Yes, that is fully correct.

    Quote Originally Posted by Reality Check View Post
    This is an orbit in three dimensions.
    Sorry.
    This is a severe violation of basic science!
    There is no way to set an orbital in three dimensions.
    There is no Zig Zag orbital revolving (Bobbing Up and Down or in and out) in the Data sheet of Newton or Kepler.
    Any orbital by definition MUST be set in two dimensions.

    Please look at the following elliptical orbit by Kepler:

    http://astronomer-wpengine.netdna-ss...06/kepler1.gif

    Quote Originally Posted by Reality Check View Post
    The Sun is not orbiting exactly parallel to the galaxy disk.
    That is also correct!

    Quote Originally Posted by Reality Check View Post
    It falls "below" the disk and gravity then pulls it up. It climbs "above" the disk and gravity pulls it down. Thus the orbit is a "sinusoidal wave" going up and down though the disk.
    Again, this is a violation of orbital revolving.
    The whole idea of kepler is that gravity holds the planet at any given moment and keep it in two dimensions.
    Therefore, there is no option for the planet to fall below the disc.
    If you can find in the spec a new Kepler law for Orbital in Three dimensions - I would like to see it
    Last edited by Dave Lee; 2018-Jan-09 at 07:11 PM.

  11. #101
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    Quote Originally Posted by Dave Lee View Post
    Sorry.
    This is a severe violation of basic science!
    There is no way to set an orbital in three dimensions.
    There is no Zig Zag orbital revolving (Bobbing Up and Down or in and out) in the Data sheet of Newton or Kepler.
    Any orbital by definition MUST be set in two dimensions.
    This is nonsense, and again reflects your limited understanding of gravity.
    Orbits are only two dimensional in central gravitational fields. Even the orbits of the moon and other Earth satellites are three dimensional.

    Grant Hutchison
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  12. #102
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    Quote Originally Posted by grant hutchison View Post
    Even the orbits of the moon and other Earth satellites are three dimensional.

    Grant Hutchison
    What do you mean please?
    Last edited by Dave Lee; 2018-Jan-09 at 07:40 PM.

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    Quote Originally Posted by Dave Lee View Post
    What do you mean?
    Earth satellites are not restricted to a plane, even in the ECEF reference frame.

    ETA: https://en.wikipedia.org/wiki/ECEF
    Last edited by grapes; 2018-Jan-09 at 07:41 PM. Reason: ETA

  14. #104
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    Quote Originally Posted by grapes View Post
    Earth satellites are not restricted to a plane, even in the ECEF reference frame.

    ETA: https://en.wikipedia.org/wiki/ECEF
    Thanks
    But that isn't an indication for any orbital of Moon, planet or star in three dimensions.

  15. #105
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    Quote Originally Posted by Dave Lee View Post
    Thanks
    But that isn't an indication for any orbital of Moon, planet or star in three dimensions.
    ?

    If they're not in a plane, they're in three dimensions...

  16. #106
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    Quote Originally Posted by Dave Lee View Post
    Quote Originally Posted by grant hutchison
    Even the orbits of the moon and other Earth satellites are three dimensional.

    Grant Hutchison
    What do you mean please?
    Exactly what I said. They do not form simple Keplerian ellipses. They have no unique orbital plane. Their orbits do not join up again after one revolution, but instead trace complex three dimensional figures around the Earth. The Earth's gravity is not a purely central force. None of Earth's satellites orbit around a unique central point.

    Grant Hutchison
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  17. #107
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    Quote Originally Posted by Dave Lee View Post
    Again, this is a violation of orbital revolving.
    The whole idea of kepler is that gravity holds the planet at any given moment and keep it in two dimensions.
    Therefore, there is no option for the planet to fall below the disc.
    A spherical body orbits a static gravitational attractor in an ellipse. Two spherical non-colliding bodies will orbit in a plane. A gravitational system with more than two bodies will no longer be stably planar - they will form a three-dimensional system (such as a galaxy or our solar system).

    https://en.wikipedia.org/wiki/Orbita...ination#Orbits

    Quote Originally Posted by Dave Lee View Post
    If you can find in the spec a new Kepler law for Orbital in Three dimensions - I would like to see it
    For an example, read up on Pierre-Simon Laplace's analysis of the stability of the solar system. Mathematical analysis of planetary motion did not cease forever in the early 1600's.

  18. #108
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    Quote Originally Posted by grant hutchison View Post
    Exactly what I said. They do not form simple Keplerian ellipses. They have no unique orbital plane. Their orbits do not join up again after one revolution, but instead trace complex three dimensional figures around the Earth. The Earth's gravity is not a purely central force. None of Earth's satellites orbit around a unique central point.

    Grant Hutchison
    This example is a very special case for satellite around the Earth. (Not Earth/Moon or Earth/Sun orbital Path)

    Never the less, it is stated:
    "The z-axis extends through True north, which does not coincide with the instantaneous earth rotational axis"

    The outcome is:
    "This means that ECEF rotates with the earth, and therefore coordinates of a point fixed on the surface of the earth do not change."

    Therefore, this example does not represent a case that the orbital object is zig zag (Up Down or In out) several times during one orbital cycle.
    Hence, it is not relevant for our discussion.
    Last edited by Dave Lee; 2018-Jan-09 at 09:05 PM.

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    Quote Originally Posted by VQkr View Post
    A spherical body orbits a static gravitational attractor in an ellipse. Two spherical non-colliding bodies will orbit in a plane. A gravitational system with more than two bodies will no longer be stably planar - they will form a three-dimensional system (such as a galaxy or our solar system).
    Sure

    However, the elliptic orbital cycle of each planet is in two dimension.
    "The inclination is one of the six orbital elements describing the shape and orientation of a celestial orbit. It is the angle between the orbital plane and the plane of reference, normally stated in degrees. "

    Therefore, as stated, this example does not represent a case that the orbital object is zig zag (Up Down or In out) several times during one orbital cycle.

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    Quote Originally Posted by Dave Lee View Post
    This example is a very special case for satellite around the Earth. (Not Earth/Moon or Earth/Sun orbital Path)
    Well, no. It's a killer counterexample to your idea that all orbits are two-dimensional. So now we can move on from that misleading idea.
    And, as it turns out, it's a completely general result, applying to all situations in which the mass distribution is not perfectly spherical; which is to say, all orbits in the Universe. (And in fact the orbit of the moon is one of the best examples of a non-Keplerian orbit we have in the solar system.)

    Hornblower has already given you a hint about how the situation of Earth-orbiting satellites can be extended to the sun's orbit around the galaxy:
    Quote Originally Posted by Hornblower View Post
    Let me add that if we could magically make the mass of the disk vanishingly small and just leave a spherical core as the significant source of gravity, the Sun would simply be in an orbit that is inclined to the plane of the disk, with one up and down cycle per orbital period. This "bobbing", which I am guessing is a popular media verbal creation, is simply a rapid precession of the plane of the orbit. If I am not mistaken, it is analogous to what a satellite in a low Earth orbit does in response to Earth's equatorial bulge, only faster in proportion to the orbital period. It makes 3 or 4 cycles per orbit, while the satellite takes many orbits to make one cycle.
    and we can get back that in more detail if you ever get around to answering my direction question:
    Quote Originally Posted by grant hutchison View Post
    If we ignore your supposed explanation for the movement, your last line answers my question. (The combined motions you describe will actually result in a trochoidal curve, not a sinusoid.)

    So as the sun moves around the galaxy, it also goes up, stops moving upwards, and then comes down again.
    And as the ball in Jens's example moves from thrower to catcher, it also goes up, stops moving upwards, and then comes down again.

    Direct question: Do you agree with that?
    Grant Hutchison
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  21. #111
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    Quote Originally Posted by Dave Lee View Post
    Sorry.
    This is a severe violation of basic science!
    The basic science is that we exist in a universe with 3 dimensions of space! Orbits are not all in the same 2 dimensional plane. Look at the various inclination of the objects in the Solar System. Look at the stars in the galaxy bulge which includes stars orbiting at different angles to the galaxy disk. They have an "orbital set in three dimensions".

    The easily learned science is that there is "Zig Zag orbital revolving (Bobbing Up and Down or in and out)" for stars in galaxy disks. A irrelevant cartoon does not change this textbook physics.

    ETA: The physical counterexample that the Earth's orbit is not 2 dimensional has already been given to you.
    Last edited by Reality Check; 2018-Jan-09 at 10:51 PM.

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  23. #113
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    Quote Originally Posted by Dave Lee View Post
    This example is a very special case for satellite around the Earth.
    You've got that completely backwards. Keplerian orbits are a simplification that only applies to 2 body systems with point masses. For any system of 3 bodies or more or incorporating mass distributions that aren't spherically symmetrical, planar orbits are the special case, and in the real world there is always variation in 3 dimensions.

    It's funny that you keep making this particular claim alongside your misunderstandings of the Lagrangian points, because orbits around those points are particularly non-Keplerian and frequently highly 3-dimensional:

    https://www.nasa.gov/sites/default/f...62311_full.jpg
    http://www-user.rhrk.uni-kl.de/~ande...on/Trojasc.jpg
    http://i.imgur.com/Yju5AFg.png
    http://www.astro.uwo.ca/~wiegert/201...1_rot02500.png
    https://en.wikipedia.org/wiki/File:E...an1st_path.jpg

  24. #114
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    Quote Originally Posted by Dave Lee View Post

    The Sun revolve around its Center of mass.
    You can call it privary point. you can call it the Sum of all the vectors form the near by stars or mass. But there is a clear point which the Sun revolve around it.
    For this discussion, lets call it "point P".
    Somehow it seems as if you are mixing up orbit with revolution. Are you talking about the sun's movement around the galaxy, or its revolution? I'm wondering, because in another post you wrote:

    The rotation of the moon is Horizontal with regards to the Earth/Sun disc plane.
    Therefore it is moving in and out.
    Are you talking about the moon's orbit, or its rotation? They are very different things, and I don't understand why you bring this up.
    As above, so below

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    Quote Originally Posted by Reality Check View Post
    The basic science is that we exist in a universe with 3 dimensions of space! Orbits are not all in the same 2 dimensional plane. Look at the various inclination of the objects in the Solar System. Look at the stars in the galaxy bulge which includes stars orbiting at different angles to the galaxy disk. They have an "orbital set in three dimensions".

    Yes, I fully agree with you.
    However,

    Quote Originally Posted by Reality Check View Post
    The easily learned science is that there is "Zig Zag orbital revolving (Bobbing Up and Down or in and out)" for stars in galaxy disks. A irrelevant cartoon does not change this textbook physics.
    You have failed to show a Zig Zag orbiting path in three dimensions by only one orbital Cycle.

    I have proved that it is feasible only by two orbital cycles.
    I have offered the Moon/Sun orbital as the ultimate solution for the Sun movement.

    Please look at the following animation:
    https://www.youtube.com/watch?v=W47Wa7onrIQ

    In this case, the moon orbits the Earth at the same disc plane as the Earth/Sun Plane.
    Now just focus on Moon/Sun orbital Cycle.
    What do we see?

    We see clearly that as the moon complete one cycle around the Sun it bobbing several times in and out (with direction to the Sun) and set a clear Zig Zag orbital cycle.

    However, in this animation the Moon/Earth Orbital plane is horizontal to the Earth/Sun orbital plane.
    Now, try to imagin that the moon/Earth orbital plane is Vertical to the Earth/Sun orbital plane.

    In this case, the moon will be bobbing up down several times before complete one cycle around the Sun.
    Hence, by two simple orbital cycles, you can get the requested Zig Zag orbital shape in the third dimension as the Sun does.

    So, there is no need for the Sun to fall from the orbital disc plane as stated:

    "it falls "below" the disk and gravity then pulls it up. It climbs "above" the disk and gravity pulls it down. Thus the orbit is a "sinusoidal wave" going up and down though the disk."

    and there is no need to pull it back to the disc plane.
    In all your examles for three dimension there is no solution for the pull back activity.
    That is clear - This is a violation of Kepler and Newton laws.

    Therefore:
    Only two simple orbital cycles is needed to complete the Sun orbital unique path around the galaxy.

    Hence, the Sun orbital Path is as follow:

    1. For the first orbital cycle:

    "The Sun orbits around the center of mass of all of the stars within its orbit around the galaxy with an influence by the mass of stars outside of the orbit."

    2. For the second orbital cycle
    This Center of mass orbits around the Galaxy.

    However,
    Now we have to show how this two layers of orbital cycles set the Unique spiral shape of the galaxy and how do we overcome on the Rotation curves problem.
    Last edited by Dave Lee; 2018-Jan-10 at 05:07 AM.

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    Quote Originally Posted by Dave Lee View Post
    In all your examles for three dimension there is no solution for the pull back activity.
    You have been given references to these solutions.

    This is a violation of Kepler and Newton laws.
    Kepler's laws don't apply to stars orbiting the galaxy.

    Newton's laws are used to calculate the fact that the sun (and other stars) will rise above and then fall back through the galactic plane. Therefore this can't violate Newton's laws.

    Only two simple orbital cycles is needed to complete the Sun orbital unique path around the galaxy.
    People might take this claim seriously if you derived it mathematically from Newton's laws of gravity.

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    Quote Originally Posted by Dave Lee View Post
    Quote Originally Posted by Reality Check
    The easily learned science is that there is "Zig Zag orbital revolving (Bobbing Up and Down or in and out)" for stars in galaxy disks. A irrelevant cartoon does not change this textbook physics.
    You have failed to show a Zig Zag orbiting path in three dimensions by only one orbital Cycle.
    No, that is the given. That motion has been calculated for us, using Newton's law of gravity.

    That was Grant's point in this post:
    Quote Originally Posted by grant hutchison View Post
    By the way, are you aware that the described movement of the sun around the galaxy is a theoretical one? We haven't been around long enough to observe it.
    The bobbing motion you're so exercised about is based on a calculation, and the calculation is derived from exactly the gravitational mathematics we've all been telling you about, and which you claim can't produce the up and down motion.
    Dave Lee, the bobbing motion has been calculated from Newton's law. Lagrange points have been shown to be a result of Newton's law.

    Grant has started another thread to discuss those Lagrange points.

    ETA: https://forum.cosmoquest.org/showthr...iility-(redux)
    Last edited by grapes; 2018-Jan-10 at 10:25 AM. Reason: Eta

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    Quote Originally Posted by Dave Lee View Post
    You have failed to show a Zig Zag orbiting path in three dimensions by only one orbital Cycle.

    I have proved that it is feasible only by two orbital cycles.
    I have offered the Moon/Sun orbital as the ultimate solution for the Sun movement.
    Once again, the motion of the sun around the galaxy has been calculated, not observed. And it has been calculated from Newtonian gravity. Job done.


    Quote Originally Posted by Dave Lee View Post
    In all your examles for three dimension there is no solution for the pull back activity.
    Quote Originally Posted by Dave Lee View Post
    That is clear - This is a violation of Kepler and Newton laws.
    Nonsense. The explanation has been given to you on multiple occasions.


    Quote Originally Posted by Dave Lee View Post
    Hence, the Sun orbital Path is as follow:

    1. For the first orbital cycle:

    "The Sun orbits around the center of mass of all of the stars within its orbit around the galaxy with an influence by the mass of stars outside of the orbit."

    2. For the second orbital cycle
    This Center of mass orbits around the Galaxy.
    Oh-ho. The trojan points have mysteriously disappeared from your argument, and you're invoking local disc stars. You're moving closer to the correct explanation.


    Quote Originally Posted by Dave Lee View Post
    However,
    Now we have to show how this two layers of orbital cycles set the Unique spiral shape of the galaxy and how do we overcome on the Rotation curves problem.
    Don't bother. You have yet to justify the strange orbits you've invented, which again ignore the extremely non-central gravity of a disc.

    And you also might get around to answering my very simple direct question, from earlier in the thread:
    Quote Originally Posted by grant hutchison View Post
    If we ignore your supposed explanation for the movement, your last line answers my question. (The combined motions you describe will actually result in a trochoidal curve, not a sinusoid.)

    So as the sun moves around the galaxy, it also goes up, stops moving upwards, and then comes down again.
    And as the ball in Jens's example moves from thrower to catcher, it also goes up, stops moving upwards, and then comes down again.

    Direct question: Do you agree with that?
    Grant Hutchison
    Last edited by grant hutchison; 2018-Jan-10 at 01:47 PM.
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    During life, we all develop attitudes and strategies to make our interactions with others more pleasant and useful. If I mention mine here, those comments can apply only to myself, my experiences and my situation. Such remarks cannot and should not be construed as dismissing, denigrating, devaluing or criticizing any different attitudes and strategies that other people have evolved as a result of their different situation and different experiences.

  29. #119
    Join Date
    Sep 2015
    Posts
    520
    Motion of Earth and Sun around the Milky Way

    Please look at the following diagram:

    https://www.physicsforums.com/thread...ky-way.888643/

    It shows a perfect image about the motions of The Earth and Moon while the Sun orbits the Galaxy.

    With regards to the Earth:
    It is clear that the Earth is bobbing up and down while it orbits the Sun.
    Same issue with the Moon.

    With regards to the orbital Sun around the Milky way:
    Based on this diagram, it seems that the upwards orbital sine wave (with reference to the galactic plane) is almost double in its amplitude comparing to the downward sine wave.
    That shows that the Sun' center of mass is not located directly at the galactic plane, but somewhere higher.
    Therefore, the Sun orbits around this Center of mass while it continue its orbital motion around the galaxy.
    As long as the Center of mass is located in the arm, there is no ploblem with that.
    Last edited by Dave Lee; 2018-Jan-10 at 06:59 PM.

  30. #120
    Join Date
    Aug 2008
    Location
    Wellington, New Zealand
    Posts
    3,800
    Quote Originally Posted by Dave Lee View Post
    However, ...
    I do not have to show you anything, especially when you have been shown it multiple times already! You even state this in a later post: It is clear that the Earth is bobbing up and down while it orbits the Sun. Same issue with the Moon.
    What mainstream physics states and physical measurements of orbits show is that real objects in orbits "bob" up in down in their orbits. The Earth is bobbing up and down because it is in a "solar disk" made of the other objects in the Solar System. The Sun is bobbing up and down because it is in a galaxy disk made of the other objects in the Milky Way.

    So formal questions to be answered by you:
    IF02a: Are you persisting in the idea that it is physically impossible for the Sun to "bob" up and down during its orbit around the center of the galaxy.
    If yes:
    IF03a: Define what you mean by "by only one orbital Cycle".
    IF03b:Show that a "Zig Zag orbiting path in three dimensions by only one orbital Cycle" is physically impossible.

    IF01: What does the Sun orbit around in your ATM idea (show your work)?
    Last edited by Reality Check; 2018-Jan-10 at 07:57 PM.

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