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Post by Andrew on Jun 6, 2015 18:57:02 GMT
[quote source="/post/105664/thread" From WUWT " Leif Svalgaard September 7, 2013 at 9:08 pm
David Thomson says: September 7, 2013 at 5:55 pmLook at the Earth – Moon system. The center of gravity of these two bodies is neither in the Earth nor the Moon, yet both orbit the barycenter. The Sun does the same thing.
Great confusion here. The Earth+Moon orbits the center of the Sun as do all other planet+moon systems. You do not need to understand the theory [although it is simple enough]. We have very precise measurements of the Earth’s orbit and they show that the E+M orbit the center of the Sun. A simple consequence hereof is the measured value of TSI which varies with the square of the distance to the center. "My bold. Leif is correct. At this very moment in time the Earth is orbiting the center of the Sun, while simultaneously the Sun is experiencing the gravitational pull of Earth. Although at each moment of time the Earth can only be orbiting the center of the Sun, when the historical orbital path is viewed, the Sun is seen to be orbiting the center of mass of the Sun and Earth. So the Sun is wobbling because of the Earth, and yet the Earth can only be orbiting the center of the sun at each moment of time.[/s] Leif knows the Sun orbits the SSBC Leif Svalgaard June 29, 2008 at 1:21 pm There are two issues here: 1) barycentric motion 2) planetary tides The standard [and correct I think] objection to the barycentric motion having any effect is that the Sun is in free fall around the barycenter and therefore does not feel any forces from that [Equivalence postulate of General Relativity or some such, or in simpler terms: the gravitational and centrifugal forces balance completely]. The standard [and correct I think] objection to the planetary tides is that they are too small. To illustrate how confusing the subject can become here are two different conversations from WUWT involving Leif Conversation 1. -------------------------------------------------------------------------------------------------- papertiger August 1, 2008 at 9:33 pm Speaking of wobbles, Jennifer Marohasy contributor, Dr. Ian Wilson of the University of Southern Queensland, has written up a study of the Sun’s orbit around the solar system’s center of gravity, and makes a case for it being in direct control of Pacific Decadal Oscillation. (PDF here) Should we be compensating the flux value for that wiggle also? Leif Svalgaard August 2, 2008 at 7:05 am papertiger: the Sun’s orbit around the solar system’s center of gravity, and makes a case for it being in direct control of Pacific Decadal Oscillation. Should we be compensating the flux value for that wiggle also? No, as the wiggle is purely fictive. It is not the Sun that moves, but the center of gravity that moves as the planets move around. So the distance between the Sun and the Earth stays what it is no matter where the other planets are [to very high precision – there are very, very tiny gravitational perturbations]. The easiest way to observationally [because I have found that many people cannot or won’t understand the theory] verify that is simply to measure the distance. The relative changes in TSI can be measured with amazing precision [0.007 W/m2 against a TSI value of 1361 W/m2 – that is 1 in 200,000], and measurements of TSI by SORCE shows that the observed values of TSI vary just as they should as if the distance between the Sun and the Earth stays what it is no matter where the other planets are. Here is a plot of the observed variation of TSI [black line] and what TSI should have been according to the barycenter people [e.g. here]. And here is their Figure 10 showing some predicted values of TSI if the Sun wiggled around. The red dots on the previous Figure show their predicted values. They do not match at all. Carsten Arnholm, Norway August 2, 2008 at 11:37 am Leif Svalgaard: “ No, as the wiggle is purely fictive. It is not the Sun that moves, but the center of gravity that moves as the planets move around.” Can you clarify this please. I think this is wrong,......
The sun clearly wiggles….Leif Svalgaard August 2, 2008 at 2:36 pm Carsten Arnholm: When one says that something moves one must also say in relation to what. As the question was if the radio flux would have to be adjusted because of the Sun’s ‘movement’, the reference point was clearly the Earth. I gave an observational test that shows that the Earth also moves such that the distance between the Sun and the Earth is that corresponding to no other planets present [the Sun and the Earth moving around ‘their’ center of mass – to high precision, if we take the barycenter to be the arbitrary reference point], hence no ‘jerking around’ of the Sun by the other planets. Did you take the trouble to go check the Figures? Or the SORCE TSI? So, just as TSI is observed not to be influenced by the wiggle, so is the f10.7 flux also not affected, as that was the answer I gave. It is utterly amazing that people still don’t get this. Conversation 2. ---------------------------------------------------------------------------------------- John-X August 3, 2008 at 4:38 pm Leif Svalgaard: You need to edit the Wikipedia page on “Center of Mass” en.wikipedia.org/wiki/Center_of_mass#Barycenter_in_astronomyto clear up the misstatements there, such as, “The Sun orbits a barycenter just above its surface” due to the mass of Jupiter. The animations on the page are very misleading, as they clearly show objects “in freefall” orbiting around a common barycenter. So if you can edit this Wikipedia page, you can probably help prevent some misunderstandings. But I don’t suppose you can do anything about this guy and his “Gravity Simulator” program, which clearly shows the discredited “Barycenter” idea, with the sun moving all around systematically in that crazy “trefoil” pattern. orbitsimulator.com/gravity/articles/ssbarycenter.html Leif Svalgaard August 3, 2008 at 9:04 pm John-X: I have no desire to rewrite the Wikipedia entry. It is OK as it is. What is wrong is how people interpret what they read. Let us go through some simplified exercises. Imagine a solar system with a Sun and a Jupiter in a perfectly circular orbit [same masses and almost same distance as our real solar system such that the Jupiter revolution takes 12 years] and for the time being, no other bodies. This is actually a fair approximation to our real system because Jupiter’s mass is greater than all the other planets together. In this system, the center of mass [CM] will be on the Sun-Jupiter line always at the same distance [1,000,000 km or so – I didn’t calculate it precisely, because it doesn’t matter much] from the center of the Sun, a bit outside of the Sun. Seen from the Sun, Jupiter will complete one full revolution every 12 years and the CM will also, because it is on the Sun-Jupiter line, always right in front of Jupiter. So, the CM orbits the Sun, as seen from the Sun. Seen from Jupiter, the Sun completes one full revolution in 12 years, and the CM also, as it is on the Jupiter-Sun line, right in front of the Sun, just a tad closer to Jupiter than the solar surface. Neither the Sun nor Jupiter will feel any forces because the gravitational force is precisely balanced by the centrifugal force of the orbital movement . At all times, the distance between the Sun and Jupiter would be the same. Seen from the CM [it is actually impossible to put a free observer there, not because the Sun is too hot, but because at the distance of only a million km from the center of the Sun, the orbital period would be very short rather than 12 years – but let that slide, this is a thought experiment after all, and as I have said in earlier posts, it is allowed to not follow the laws of Nature] The Sun would be observed by that observer to revolve about the CM in precisely 12 years and Jupiter would too, located at the opposite point in the sky. Because an observer on the Sun already does not feel any forces [we are ignoring the already calculated minute tidal forces that raise the surface by a hard to measure one thousandth of a meter], us placing an imagined observer at the CM seeing the Sun compete a very tight orbit about the CM would not suddenly cause the observer on the Sun to feel anything. I could now add another planet [or my little pea from a previous discussion] to displace the CM somewhat. That would still not affect the motion of Jupiter and the Sun [except from very, very small gravitational perturbations], nor, all the sudden cause the observer on the Sun to begin to feel any forces. The CM would now not move in the neat circles from before, but in a more complicated path because of the new planet. Seen from the Sun, the two planets would still move in their perfectly circular orbits with their distances being constant. But, as the CM now moves in a complicated path, the Sun [and the planets] will seen from the gyrating CM move in correspondingly complicated orbit{s}. But this is only because we have chosen to view the Sun from a wildly moving point, just like the trees on a downhill mountain side seem to weave left and right seen by a slalom skier completing her run.
This is about as clear as I can make it. If this does not work, I don’t know what else to say.
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Post by icefisher on Jun 7, 2015 1:41:36 GMT
Actually what Leif is guilty of is obfuscating the issue. There is absolutely nothing wrong with what David Thomson wrote in any way.
Leif though apparently disagrees on related matters presented by Thomson (climate affects of the planets). Since he has no argument regarding those related matters, he instead is attempting to obfuscate Thomson's correct observation that the center of gravity moves in relationship to the sun by claiming confusion where no confusion exists. The confusion Svalgaard sees is other readers when aware of the truth put forth by Thomson might actually begin to accept the possibility that climate might be controlled by something other than CO2
So Svalgaard is wrong here. He is wrong in the sense that he is the one both suggesting a confusion and then itemizing it as a confusion when it has nothing whatsoever to do with the implications of the thread. Classic obfuscation.
If Svalgaard had wanted to avoid the obfuscation he could have by saying what Thomson said about the barycenter was correct but that it might be useful to understand what he was going to add to it. However, since he was in dispute with Thomson and his addition was essentially irrelevant that would have hardly served the purpose of the comment.
Beyond that Thomson had argued that when the barycenter crosses the sun it causes a change in magnetic fields.
Here is Thomson's entire post that Leif was responding to:
David Thomson September 7, 2013 at 5:55 pm
"Carsten Arnholm says: September 7, 2013 at 4:53 pm The barycenter is not “solar”. The Barycenter is the center of mass of the solar system. It is not physical in any other way. It cannot “act” on the core of the Sun, being it solid or not. In fact the barycenter cannot act on anything…"
Thomson: the center of the solar system is not at the center of the Sun, then why would you not think the Sun would be gravitationally moved? The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun orbits the center of the solar system the same as the planets do."
Look at the Earth – Moon system. The center of gravity of these two bodies is neither in the Earth nor the Moon, yet both orbit the barycenter. The Sun does the same thing.
The Sun is not in a simple binary system as are the Earth and Moon. The Sun’s orbit around the solar barycenter is wildly variable on the scale of hundreds of years. The variability is what shakes up the Sun’s core and modulates its magnetohydrodynamic systems.
Eventually when this obfuscation does not work. Leif will then say heck the force is only enough to deform the surface by <2mm. But the truth is we don't know what it takes to modify "magnetohydrodynamic systems".
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Post by Andrew on Jun 7, 2015 4:38:01 GMT
Actually what Leif is guilty of is obfuscating the issue. There is absolutely nothing wrong with what David Thomson wrote in any way. Leif though apparently disagrees on related matters presented by Thomson (climate affects of the planets). Since he has no argument regarding those related matters, he instead is attempting to obfuscate Thomson's correct observation that the center of gravity moves in relationship to the sun by claiming confusion where no confusion exists. The confusion Svalgaard sees is other readers when aware of the truth put forth by Thomson might actually begin to accept the possibility that climate might be controlled by something other than CO2 So Svalgaard is wrong here. He is wrong in the sense that he is the one both suggesting a confusion and then itemizing it as a confusion when it has nothing whatsoever to do with the implications of the thread. Classic obfuscation. If Svalgaard had wanted to avoid the obfuscation he could have by saying what Thomson said about the barycenter was correct but that it might be useful to understand what he was going to add to it. However, since he was in dispute with Thomson and his addition was essentially irrelevant that would have hardly served the purpose of the comment. Beyond that Thomson had argued that when the barycenter crosses the sun it causes a change in magnetic fields. Here is Thomson's entire post that Leif was responding to: David Thomson September 7, 2013 at 5:55 pm"Carsten Arnholm says:September 7, 2013 at 4:53 pmThe barycenter is not “solar”. The Barycenter is the center of mass of the solar system. It is not physical in any other way. It cannot “act” on the core of the Sun, being it solid or not. In fact the barycenter cannot act on anything…"Thomson: the center of the solar system is not at the center of the Sun, then why would you not think the Sun would be gravitationally moved? The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun orbits the center of the solar system the same as the planets do."Look at the Earth – Moon system. The center of gravity of these two bodies is neither in the Earth nor the Moon, yet both orbit the barycenter. The Sun does the same thing.The Sun is not in a simple binary system as are the Earth and Moon. The Sun’s orbit around the solar barycenter is wildly variable on the scale of hundreds of years. The variability is what shakes up the Sun’s core and modulates its magnetohydrodynamic systems.Eventually when this obfuscation does not work. Leif will then say heck the force is only enough to deform the surface by <2mm. But the truth is we don't know what it takes to modify "magnetohydrodynamic systems". As pointed out by another poster that day there is an obvious mistake in Thompsons 2nd paragraph. Thompson quickly realised this and replies 'oops my bad' Thomsons text can therefore be written like this: the center of the solar system is not at the center of the Sun, then why would you not think the Sun would be gravitationally moved? The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun orbits the center of the solar system the same as the planets do."
The Sun is not in a simple binary system as are the Earth and Moon. The Sun’s orbit around the solar barycenter is wildly variable on the scale of hundreds of years. The variability is what shakes up the Sun’s core and modulates its magnetohydrodynamic systems. The relevant part for a reply then becomes this part >>The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun is not pulled towards "the centre of the solar systems gravity". It is pulled towards the planets gravity. Likewise the ISS is not pulled towards "the centre of the Earth moon systems gravity". A barycenter has no properties or abilities to change anything. The barycenter is mathematically the center of mass. The only thing capable of changing anything are the individual objects in the system. There is absolutely nothing wrong with what David Thomson wrote in any way. There are two mistakes in Thomsons text. One he realises and one he does not realise Leif .....is attempting to obfuscate Thomson's correct observation that the center of gravity moves in relationship to the sunMost of this "center of gravity" is created by the Sun. If I assume you do not mind me removing the effect of the suns gravity upon itself from the bolded text, we are left with "the gravitational pull of the planets moves in relationship to the sun" From leifs reply to thomson Leif Svalgaard September 7, 2013 at 9:08 pm Great confusion here. The Earth+Moon orbits the center of the Sun as do all other planet+moon systems. You do not need to understand the theory [although it is simple enough]. We have very precise measurements of the Earth’s orbit and they show that the E+M orbit the center of the Sun. A simple consequence hereof is the measured value of TSI which varies with the square of the distance to the center.Leif is referring to the JPL ephemerides which he has referred to elsewhere on WUWT which he says are given to 7 decimal places to give a resolution of a few cms. In the above text Leif says there are no detectable movements that can be asigned to something "created by the barycenter" either in the JPL results or the TSI results. To reduce this down further, Leif is saying, more or less, it does not matter if you cannot understand why the barycenter cannot change anything, because our most accurate tests reveals that nothing is changed even if it were capable of changing anything.
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Post by icefisher on Jun 7, 2015 8:14:24 GMT
As pointed out by another poster that day there is an obvious mistake in Thompsons 2nd paragraph. Thompson quickly realised this and replies 'oops my bad' Thomsons text can therefore be written like this: the center of the solar system is not at the center of the Sun, then why would you not think the Sun would be gravitationally moved? The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun orbits the center of the solar system the same as the planets do."
The Sun is not in a simple binary system as are the Earth and Moon. The Sun’s orbit around the solar barycenter is wildly variable on the scale of hundreds of years. The variability is what shakes up the Sun’s core and modulates its magnetohydrodynamic systems. The relevant part for a reply then becomes this part >>The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun is not pulled towards "the centre of the solar systems gravity". It is pulled towards the planets gravity. Likewise the ISS is not pulled towards "the centre of the Earth moon systems gravity". A barycenter has no properties or abilities to change anything. The barycenter is mathematically the center of mass. The only thing capable of changing anything are the individual objects in the system. thats total nonsense Andrew. You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. Go back and review your force vectors in high school physics. The sun is pulled to it and the planets are pulled to it. And since the planets have a gravity independent speed vector as they move the center of gravity moves. If Saturn and Jupiter are on one side of the sun and in line, the center of gravity is moved further from the sun, if they are on opposite sides it moves closer to the sun, if they are at right angles the center of gravity moves to a position out of line between the two lines connecting the center points of the planets to the center point of the sun. Now you have to also consider the effect of the 7 other planets so it gets a bit complicated. There is absolutely nothing wrong with what David Thomson wrote in any way. There are two mistakes in Thomsons text. One he realises and one he does not realise Leif .....is attempting to obfuscate Thomson's correct observation that the center of gravity moves in relationship to the sunMost of this "center of gravity" is created by the Sun. If I assume you do not mind me removing the effect of the suns gravity upon itself from the bolded text, we are left with "the gravitational pull of the planets moves in relationship to the sun" From leifs reply to thomson Leif Svalgaard September 7, 2013 at 9:08 pm Great confusion here. The Earth+Moon orbits the center of the Sun as do all other planet+moon systems. You do not need to understand the theory [although it is simple enough]. We have very precise measurements of the Earth’s orbit and they show that the E+M orbit the center of the Sun. A simple consequence hereof is the measured value of TSI which varies with the square of the distance to the center.Leif is referring to the JPL ephemerides which he has referred to elsewhere on WUWT which he says are given to 7 decimal places to give a resolution of a few cms. In the above text Leif says there are no detectable movements that can be asigned to something "created by the barycenter" either in the JPL results or the TSI results. To reduce this down further, Leif is saying, more or less, it does not matter if you cannot understand why the barycenter cannot change anything, because our most accurate tests reveals that nothing is changed even if it were capable of changing anything. It may well be that Svalgaard is spewing nonsense as you think he is. I have stated that I believe that the earth orbits the sun center and the barycenter. Thats because if you plot the sun's orbit around the barycenter its average position is the barycenter even though it may never sit on it. The earth precisely orbits the sun but while this is going on the sun (and the earth) is being pulled in the direction of Jupiter while Jupiter is being pulled toward the sun (and earth). If Jupiter did not have an independent speed vector it would plummet almost like a stone into the sun. They would collide in space. But Jupiter's independent speed vector is just right to keep it circling the sun without its orbit decaying. Now Svalgaard no doubt has opinions that the rotation around the barycenter changes nothing. But he does turn right around and acknowledge a planetary deformation from the very same force vectors that the barycenter is constructed from. The point where the sum of the vectors converge is nothing more than a high school physics exercise in 3 dimensional vectors. This point moves around within and outside of the sun. The moving tidal deformation moves around the sun at approximately the rotation rate of the sun so indeed minor changes in the gravitational pull vectors would not be expected to provide much variance to the tides but indeed they do provide some. So once you understand Andrew that the barycenter is not a mythical mathematical construct that represents "nothing is changed" but instead is a mathematical construct of real gravitational force vectors it should dawn on you that indeed the movement of the barycenter does cause change, the only argument is whether its enough change to explain what people are trying to explain. I am not sure what Nautonnier was thinking and saying about Leif as I never found anything as explicit as what you laid out above. But the hilarious part Andrew is you have given complete cover to Nautonnier in whatever he was thinking as you yourself are actually still muddled up over what the barycenter is. Svalgaard may hold the opinion it amounts to nothing important but I am not sure that should be confused with your confusion. Like I said I saw it as Svalgaard obfuscating and not saying what you attribute him saying. You see it (and maybe Nautonnier also) sees it as Svalgaard actually saying the barycenter has no physical reality when clearly it does. Either way Nautonnier understands the barycenter and you do not. Fact is our tides change for the same reasons. The moon is the primary tide maker but when aligned with the sun, about every two weeks we have higher tides. Then seasonally we have larger tides via the earth's orbit position with the sun (closer/further away). The other planets affect our tides likewise albeit to a far lesser degree. Your interpretation that Svalgaard has accurately measured the earth's orbit and concluded that the barycenter is a unreal concept that is capable of changing nothing is complete nonsense its not a matter of zero change its a matter of how much change. Its not exactly rare to see scientists make these nonsense arguments on a whole variety of issues but this one is in complete denial of some of the most basic physics, that of gravity. In many respects this argument is like this. I argue I will drive my car to the church and not go off the road. Svalgaard argues the church is not in the road so I cannot drive my car there without going off the road. In common parlance my argument is sound and Svalgaard is obfuscating. Then you step in and argue Svalgaard is right because there is no such thing as a car. The only thing I left out is a church that is constantly changing sides of the street it is on.
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Post by Andrew on Jun 7, 2015 10:27:05 GMT
>>The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. The Sun is not pulled towards "the centre of the solar systems gravity". It is pulled towards the planets gravity. Likewise the ISS is not pulled towards "the centre of the Earth moon systems gravity". A barycenter has no properties or abilities to change anything. The barycenter is mathematically the center of mass. The only thing capable of changing anything are the individual objects in the system. thats total nonsense Andrew. You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. Nothing is being pulled towards the SSBC except by coincidence. The only relevant forces are the Sun and whatever else is in the solar system. For example when the SSBC is just above the surface of the Sun, the solar flares that eject billions of tonnes of material that suspend momentarily above the Sun do not remain suspended just above the Sun. Similarly the Sun does not cleave into two large parts when the SSBC passes thru it. The Sun remains round.
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Post by icefisher on Jun 7, 2015 18:33:50 GMT
thats total nonsense Andrew. You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. Nothing is being pulled towards the SSBC except by coincidence. The only relevant forces are the Sun and whatever else is in the solar system. For example when the SSBC is just above the surface of the Sun, the solar flares that eject billions of tonnes of material that suspend momentarily above the Sun do not remain suspended just above the Sun. Similarly the Sun does not cleave into two large parts when the SSBC passes thru it. The Sun remains round. The pull is evidenced by the tidal height Andrew. Do you actually believe there is no pull and the tide piles up all by itself? Are you in denial of some of the best known astronomical physics and the laws of gravity? That pull that creates the tides comes from every planet in the solar system and the direction of the pull is the sum of the gravitational vectors. The sun itself is in freefall. Its own gravity does not drive a motive force for the sun, but the pull of the planets do. Since there is zero resistance to the sun moving in space this pull accelerates the sun towards the barycenter. However, it never or seldom centers on the barycenter because the direction of the force is constantly changing so the barycenter is constantly moving out of the path of the sun. The result as it is for planets is an orbit. This is not complicated stuff Andrew. Spend a few minutes thinking about it. What is complicated is understanding how these forces might work to affect the sun's activity and climate on earth. The gravitational acceleration moving the sun toward the barycenter is very small and it varies as planets change their relative positions. The terminal velocity of the sun towards the barycenter as I recall quite small. Stars with planet systems are identified by this changing direction of orbit creating color shifts. Instruments today I believe are precise enough to detect color shifts from Jupiter or larger planets. Thats the "demonstrated" truth of the theory, only stars with planets have this occuring, what the star is circling is called a barycenter (though its probably empty space) and EUREKA its caused by the planets moving the sun toward the barycenter which is the point identified by the gravitational center/barycenter of the solar system. Svalgaard has questioned what affect such extremely small acceleration rate changes could have on the sun or the climate, which is fine, it is a real puzzle. I suggest you go suggest to Leif on the other forum that the fact that solar flare materials do not remain suspended over the surface the sun is sufficient proof that there is no pull, no acceleration, or no movement of the sun towards the barycenter. He should get a good hearty belly laugh out of that. An extension of your nonsense argument would be arguing that because materials ejected above the surface of the earth remain there is sufficient evidence that the earth is not in orbit. Pour some icewater on your ego and understand. The final piece to discuss is whether the earth circles the barycenter of the center of the sun. I think the earth is pulled toward the barycenter and ends up circling it and the center of the sun. Calculations proving that the earth circles the sun I believe are a product of the calculations used that incorporate barycenter whether explicitly or not. If Svalgaard thinks differently on that I would be interested in discussing why but not via the use of your argument that solar ejecta returning to the surface of the sun is evidence of no pull on the sun.
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Post by Andrew on Jun 7, 2015 19:18:02 GMT
Nothing is being pulled towards the SSBC except by coincidence. The only relevant forces are the Sun and whatever else is in the solar system. For example when the SSBC is just above the surface of the Sun, the solar flares that eject billions of tonnes of material that suspend momentarily above the Sun do not remain suspended just above the Sun. Similarly the Sun does not cleave into two large parts when the SSBC passes thru it. The Sun remains round. The pull is evidenced by the tidal height Andrew. Do you actually believe there is no pull and the tide piles up all by itself? Are you in denial of some of the best known astronomical physics and the laws of gravity? That pull that creates the tides comes from every planet in the solar system and the direction of the pull is the sum of the gravitational vectors. The sun itself is in freefall. Its own gravity does not drive a motive force for the sun, but the pull of the planets do. Since there is zero resistance to the sun moving in space this pull accelerates the sun towards the barycenter. However, it never or seldom centers on the barycenter because the direction of the force is constantly changing so the barycenter is constantly moving out of the path of the sun. The result as it is for planets is an orbit. This is not complicated stuff Andrew. Spend a few minutes thinking about it. What is complicated is understanding how these forces might work to affect the sun's activity and climate on earth. The gravitational acceleration moving the sun toward the barycenter is very small and it varies as planets change their relative positions. The terminal velocity of the sun towards the barycenter as I recall quite small. Stars with planet systems are identified by this changing direction of orbit creating color shifts. Instruments today I believe are precise enough to detect color shifts from Jupiter or larger planets. Thats the "demonstrated" truth of the theory, only stars with planets have this occuring, what the star is circling is called a barycenter (though its probably empty space) and EUREKA its caused by the planets moving the sun toward the barycenter which is the point identified by the gravitational center/barycenter of the solar system. Svalgaard has questioned what affect such extremely small acceleration rate changes could have on the sun or the climate, which is fine, it is a real puzzle. I suggest you go suggest to Leif on the other forum that the fact that solar flare materials do not remain suspended over the surface the sun is sufficient proof that there is no pull, no acceleration, or no movement of the sun towards the barycenter. He should get a good hearty belly laugh out of that. An extension of your nonsense argument would be arguing that because materials ejected above the surface of the earth remain there is sufficient evidence that the earth is not in orbit. Pour some icewater on your ego and understand. The final piece to discuss is whether the earth circles the barycenter of the center of the sun. I think the earth is pulled toward the barycenter and ends up circling it and the center of the sun. Calculations proving that the earth circles the sun I believe are a product of the calculations used that incorporate barycenter whether explicitly or not. If Svalgaard thinks differently on that I would be interested in discussing why but not via the use of your argument that solar ejecta returning to the surface of the sun is evidence of no pull on the sun. I have no idea what you are talking about. The tides are created via the effect of planets gravity which are in turn pulling on the Sun. There is no center of gravity at the SSBC. At the SSBC distance from the Sun, the pull of the sun at that distance is hundreds of thousands times the pull of Jupiter. Even at the distance of the Earth the pull of jupiter is only .0062% that of the Sun when Jupiter is closest to the Earth. Obviously an object placed in the exact center of the barycenter will immediately fall towards the Sun Nothing is being pulled towards the SSBC by the SSBC. The only relevant forces are the Sun and whatever else is in the solar system. >>You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. Obviously notIf all of the solar system objects were lined up on the same side, the sun would feel a significant force in the direction of the line, but an object at Earth distance from the sun at right angles to the line would very strongly head towards the Sun with only a very tiny force upon it to cause a course deviation created by the rest of the solar system.
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Post by Andrew on Jun 7, 2015 20:46:00 GMT
your argument that solar ejecta returning to the surface of the sun is evidence of no pull on the sun. As I explained clearly, what I said is evidence for the SSBC not being "the center of the solar systems gravity", and as I explained countless times to Nautonnier and yourself the sun is being pulled around the solar system by the planets, and for the record if you continue to f.uck around with me like this we are done and it will happen quickly. I am totally sick of the strange way you behave. I am expecting you to have a normal point by point conversation with me where you make an honest attempt to understand what I am saying and you show you are interested in learning one way or another. I suggest you go suggest to Leif on the other forum that the fact that solar flare materials do not remain suspended over the surface the sun is sufficient proof that there is no pull, no acceleration, or no movement of the sun towards the barycenter. He should get a good hearty belly laugh out of that If you once more remotely attempt to play this stupid game again we are done. If you not understand something the normal way to behave in a conversation is to highlight what you do not understand and then wait for an answer. Thomson said: >>The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. Leif responded by saying 'Great confusion here'. Actually what Leif is guilty of is obfuscating the issue. There is absolutely nothing wrong with what David Thomson wrote in any way. Any object placed at "the center of the solar systems gravity" aka the SSBC (I assume) will immediately fall towards the Sun. If you disagree you should give the reasons why you diagree and we can take it from there. If you cannot respond in a normal civilised manner we are done. Anger is fine, but this stupid baiting has to end or we are done. Obviously we have a point of disagreement, if you make any attempt to derail the conversation by going off on some irrelevant tangent or you produce reams of text barely related to the topic at hand we are done.
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Post by flearider on Jun 7, 2015 21:19:39 GMT
boys play nice or go to your rooms .. don't make me get the stick out .. or get on the same page .. ones talking about earth tidal forcing the other about planetary tidal forcing ..
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Post by Andrew on Jun 7, 2015 21:28:53 GMT
ones talking about earth tidal forcing the other about planetary tidal forcing .. What makes you think that? Who is talking about Earth tides? What do you mean by earth tidal forcing?? The only relevant tides for the conversation are Solar tides created by the non-solar objects in the solar system
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Post by icefisher on Jun 8, 2015 1:00:58 GMT
your argument that solar ejecta returning to the surface of the sun is evidence of no pull on the sun. As I explained clearly, what I said is evidence for the SSBC not being "the center of the solar systems gravity", and as I explained countless times to Nautonnier and yourself the sun is being pulled around the solar system by the planets, and for the record if you continue to f.uck around with me like this we are done and it will happen quickly. I am totally sick of the strange way you behave. I am expecting you to have a normal point by point conversation with me where you make an honest attempt to understand what I am saying and you show you are interested in learning one way or another. I suggest you go suggest to Leif on the other forum that the fact that solar flare materials do not remain suspended over the surface the sun is sufficient proof that there is no pull, no acceleration, or no movement of the sun towards the barycenter. He should get a good hearty belly laugh out of that If you once more remotely attempt to play this stupid game again we are done. If you not understand something the normal way to behave in a conversation is to highlight what you do not understand and then wait for an answer. Thomson said: >>The Sun has no choice, except to be pulled toward the center of the solar system’s gravity. Leif responded by saying 'Great confusion here'. Actually what Leif is guilty of is obfuscating the issue. There is absolutely nothing wrong with what David Thomson wrote in any way. Any object placed at "the center of the solar systems gravity" aka the SSBC (I assume) will immediately fall towards the Sun. If you disagree you should give the reasons why you diagree and we can take it from there. You remain completely muddled up. Of course an object (with no speed) at the barycenter would fall into the sun, Jupiter would too if it did not have orbital speed and it is much further out from the barycenter than the barycenter itself. The only reason the sun orbits the barycenter and the planet continue to orbit the sun instead of collapsing into the barycenter is the speed of the planets that maintains their orbit and as a result a changing direction of forces as the planets move that make for an orbit. Since Jupiter is so big so as to override The barycenter is a mathematical sumation of all the gravity force vectors converging on a single point. If the planets were frozen in space the sun would move to the barycenter. Its only their movement that maintains their relative altitude from the sun as they are moving independently tangent to their orbit and the curvature of the orbit is the force on the planet exerted by the sun. Here is a pictorial sample of how to calculate its location. We did these kinds of calculations in my high school physics course This is not to true scale and it only has two planets and the actual summation vector is merely eyeballed. Since when you become muddled up your brain synapses short circuit for an infusion of ego juice, I suggest you go ask somebody you will actually listen to as opposed to merely spouting mumbo jumbo back at me.
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Post by sigurdur on Jun 8, 2015 1:25:10 GMT
Andrew: The planets do NOT pull the sun around.
Where the SUN goes, the planets will follow.
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Post by Andrew on Jun 8, 2015 4:45:36 GMT
Of course an object (with no speed) at the barycenter would fall into the sun, So we have established we agree on that. It seems to me that in order to construct a diagram of solar system gravitational influences you need to calculate using Newtons Universal law of gravity where gravity varies directly with the Mass and inversely as the cubes of their distances. The centre of mass is not particularly relevant as far as I can see for calculating what impact the planets now have on the Sun. Presumably if you use Newtons gravity law the centre of gravity remains very close to the center of the sun at all times. Anyway, Venus Mercury and the Earth have more average influence upon the Sun than Jupiter Saturn Uranus and Neptune At a ratio of Venus, mars, Earth 4,40 compared to all the rest of only 2.460. Venus alone is almost the same as Jupiter. adsabs.harvard.edu/full/1927PASP...39..228LThe tide raising forces of the planets vary directly as their masses and inversely as the cubes of their distances from the Sun. The mean relative tidal forces of the planets are are: Jupiter, 2.30 Venus, 2.16 Mercury 1.24 Earth, 1.00 Saturn 0.11 Mars 0.03 Uranus 0.019 Neptune 0.001
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Post by icefisher on Jun 8, 2015 8:55:01 GMT
You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. What does the bolded text mean? See Below If all of the solar system objects were lined up on the same side, the sun would feel a significant force in the direction of the line, but if a new earth sized object was placed at Earth distance from the sun at right angles to the line, the new object would very strongly head towards the Sun with only a very tiny force upon it to cause a course deviation created by the rest of the solar system. Please clearly state what parts of that you disagree with. No way do I disagree since its exactly what I drew above. . . .albeit not to scale and with Saturn and Jupiter as the only planets. You only left out a few things. 1) that the sun would also head for that deviation point. Thats basic physics. A constant force acting on a frictionless body will always cause that body to move in the direction of the force. There is no known minimum force on a frictionless body that would cause it not to move. 2) you left out whether the objects were in stablized orbit or not. If they had no orbit velocity they would fall towards the sun and the sun would fall toward the planets and they would collide near that point (a bit before there centers get to the barycenter). But in a stablized orbit the sun is going to circle the barycenter. If you have only two earths in the system at right angles and a few light years from the sun the deviation would be the same but the orbit of the sun around the barycenter would be much larger and in recognition of stablized orbits the period of that orbit would be very long. Replace the earths with 2 Jupiters in the same positions as the earths and the deviation will be greater and the orbit of the sun around the barycenter as a result will also be greater. These can be calculated using trigonometry. In these binary systems there is no deviation of the barycenter. The deviation gets introduced by adding planets to the system and you end up with this barycenter moving all over the place with multiple deviations and different forces being applied to the sun.
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Post by Andrew on Jun 8, 2015 9:12:28 GMT
What does the bolded text mean? See Below If all of the solar system objects were lined up on the same side, the sun would feel a significant force in the direction of the line, but if a new earth sized object was placed at Earth distance from the sun at right angles to the line, the new object would very strongly head towards the Sun with only a very tiny force upon it to cause a course deviation created by the rest of the solar system. Please clearly state what parts of that you disagree with. No way do I disagree since its exactly what I drew above. . . .albeit not to scale and with Saturn and Jupiter as the only planets. You only left out a few things. 1) that the sun would also head for that deviation point. Thats basic physics. A constant force acting on a frictionless body will always cause that body to move in the direction of the force. There is no known minimum force on a frictionless body that would cause it not to move. 2) you left out whether the objects were in stablized orbit or not. If they had no orbit velocity they would fall towards the sun and the sun would fall toward the planets and they would collide near that point (a bit before there centers get to the barycenter). But in a stablized orbit the sun is going to circle the barycenter. If you have only two earths in the system at right angles and a few light years from the sun the deviation would be the same but the orbit of the sun around the barycenter would be much larger and in recognition of stablized orbits the period of that orbit would be very long. Replace the earths with 2 Jupiters in the same positions as the earths and the deviation will be greater and the orbit of the sun around the barycenter as a result will also be greater. These can be calculated using trigonometry. In these binary systems there is no deviation of the barycenter. The deviation gets introduced by adding planets to the system and you end up with this barycenter moving all over the place with multiple deviations and different forces being applied to the sun. >>You only left out a few things. 1. >>that the sun would also head for that deviation point. Thats basic physics. A constant force acting on a frictionless body will always cause that body to move in the direction of the force. There is no known minimum force on a frictionless body that would cause it not to move. Why did you add that comment??? Why are you constantly adding these comments?Nobody in astrophysics is disputing the sun is influenced by the planets so it should not be necessary to include that 2. My thought experiment was just the solar system with the addition of a new stationary object at Earth distance >>You don't understand what a Barycenter is. Sure its a mathematical construct but it is a mathematical construct of real gravitational forces. All the objects in the solar system are pulled to this point as its the point of where all the forces balance out and anything outside of that point is attracted to it like a magnet. I do not understand this text.If we change the thought experiment and place all of the planets in line on the same side of the Sun and exclude the Earth and place the Earth 90 degrees to the line and have a normal solar system but then stop the Earth, the Earth will not pass thru the barycenter. The gravitational pull is according to newtons gravity law where gravity weakens at the square of the distance so Jupiter Saturn Uranus, Neptune combined have less influence on the falling earth than Mercury and Venus combined. The situation is a bit complex because it takes 65 days for the Earth to hit the Sun. The Mars Jupiter Saturn etc force will be almost constant while the Suns force increases rapidly. There is though an almosts constant jupiter force upon the falling Earth of 0.0062% of the beginning Solar force but the constant jupiter force is only a bit less than the force venus would apply at impact if venus remained in line with Jupiter. Saturn and beyond only apply a very small force upon the falling Earth. >>In these binary systems there is no deviation of the barycenter. That animation shows the barycenter in a fixed position where the Frame Of Reference (FoR) is the BC. The BC is always in a fixed position for the FoR of the BC. Usually we have shown the BC with the FoR of the Sun.
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