OK, this is something of a ‘marker posting’. Not a lot of ‘great insight’ but marking the existence of something I’ve been trying to show “exists” for a couple of years now. That is “Spin Orbit Coupling” at the macro level.
Substantially every time I’ve got on a Google Train of “Spin Orbit Coupling” it’s pulled into a sub atomic station. It’s just all over the place at that scale. You can’t hardly say “particle” without some kind of spin orbit coupling effect popping up.
Physics (like the conservation of angular momentum) implied to me that this is a property that ought to exist at all physical scales. I could not imagine a way to have angular momentum act differently at the sub atomic scale than at the macro… Yet despite my expectation, I could find almost nothing that said “spin orbit coupling” in the context of “planet”. The one exception being a paper by Ian Wilson that showed a Length Of Day (LOD) correlation with the PDO and correlation with the solar system orbital state. Yet “mainstream” climate folks were not keen on that paper, so I wanted ‘more than one’ reference. That, and the lack of other references was a bit unnerving.
But now I’ve run into a couple of more examples.
Why Does This Matter?
So, who cares? Well, the whole complaint about the “Solar output modulated by planets” thesis comes down to “only tides can happen and they are too small to matter”. But if there can be spin-orbit couples, then the entire Angular Momentum of the outer planets can have impact. As Angular momentum increases greatly with Radius, this means they could have a lot of ‘pull’ ;-) (Please, it’s only a little pun…)
Basically, if Spin Orbit Coupling is active and recognized at the macro / planet level, then folks need to address the question of what is happening to solar SPIN when the Angular Momentum of the solar system changes as the barycenter moves into and out of the sun. Having a spin change (even, or perhaps especially) if concentrated into particular layers or bands, could easily explain planetary modulation of solar output.
So where did I find a reference?
First, the bad news: It’s largely Wikipedia.
Second, the good news: The articles are not contentious, so ought to be fairly politically neutral. (Though now that I’ve tied them to Global Warming there is the risk that the Political Thought Police of AGW will go and erase or re-write them.)
For an example of the typical, highly subatomic particle oriented article, there is this one:
Just full of stuff that sounds very sub-atomic specific and particle centric:
In quantum physics, the spin-orbit interaction (also called spin-orbit effect or spin-orbit coupling) is any interaction of a particle’s spin with its motion. The first and best known example of this is that spin-orbit interaction causes shifts in an electron’s atomic energy levels due to electromagnetic interaction between the electron’s spin and the nucleus’s magnetic field. This is detectable as a splitting of spectral lines. A similar effect, due to the relationship between angular momentum and the strong nuclear force, occurs for protons and neutrons moving inside the nucleus, leading to a shift in their energy levels in the nucleus shell model. In the field of spintronics, spin-orbit effects for electrons in semiconductors and other materials are explored and put to useful work.
Then here are two places where I’ve found a non-particle level reference:
While much of that article is about sub-atomic spin-orbit coupling, it contained this giant gem:
In astronomy, spin-orbit coupling reflects the general law of conservation of angular momentum, which holds for celestial systems as well.
EXACTLY what I was looking for. My understanding that physics of momentum is the same at any and ALL scales, reflected in this one statement. I know, I ought not to have been so tentative about it and I ought to have just baldly asserted that it was the case. But there are enough things that are ‘different’ in the sub-atomic and quantum worlds that I was leery of just leaping from that to the Galactic without a bit of moral support / confirmation. It goes on:
In simple cases, the direction of the angular momentum vector is neglected, and the spin-orbit coupling is the ratio between the frequency with which a planet or other celestial body spins about its own axis to that with which it orbits another body. This is more commonly known as orbital resonance. Often, the underlying physical effects are tidal forces.
This lead to the insight that there was a ‘name change’ hiding the connection. That in astronomy, the concept was being hidden in / blended with “Orbital Resonance”. So here we have The Giant Missing Clue. The name was changed. But the point is clearly made that ‘body spin” can be interchanged with orbital rotation. Just like the earth spin is being changed by the moon via tides. I note in passing that it says “Often” … “effects are tidal forces.” (but not always?)
Also of note is that statement that the angular momentum vector is neglected in “simple cases”. Astronomy seems over full of “neglecting” and “simple cases”. In particular I note that they say when the momentum vector is ignored it is often called “orbital resonance”. OK, but what if I don’t want to ignore that vector? This, I think, is where the improvement will come. Just apply straight Angular Momentum physics, but do all of it this time…
But at least now we have something (even if small) to point at when asserting that maybe, just maybe, that whole Solar System Barycenter Conservation Of Planetary Angular Momentum thing could actually stir the sun up a bit. Be it “spin”, or “tides”, or “nutation”, or “precession”, or …
The problem is no longer “Can it?”. The problem is now “What happens to the COMBINED angular momentum of ALL the planets AND the sun as orbital positions change? How does this change the solar motions?”. And given that Angular Momentum is dominated by the Radius, there is A LOT of angular momentum to spread around.
Types of resonance
In general, an orbital resonance may:
involve one or any combination of the orbit parameters (e.g. eccentricity versus semimajor axis, or eccentricity versus orbit inclination).
act on any time scale from short term, commensurable with the orbit periods, to secular, measured in 104 to 106 years.
lead to either long term stabilization of the orbits or be the cause of their destabilization.
So any orbital feature can be involved, and that includes things like pole precession, nutation (“wobble”), etc. And this implied, through them, to spin.
A Lindblad resonance drives spiral density waves both in galaxies (where stars are subject to forcing by the spiral arms themselves) and in Saturn’s rings (where ring particles are subject to forcing by Saturn’s moons).
A secular resonance occurs when the precession of two orbits is synchronised (usually a precession of the perihelion or ascending node). A small body in secular resonance with a much larger one (e.g. a planet) will preecess at the same rate as the large body. Over long times (a million years, or so) a secular resonance will change the eccentricity and inclination of the small body.
I note in passing that “forcing” is starting to show up here, as well. IFF they mean “force” they ought to say so. If they mean a mathematical “forcing function” they ought to say that instead (and state the “given function” so we know what function they are talking about…)
Several prominent examples of secular resonance involve Saturn. A resonance between the precession of Saturn’s rotational axis and that of Neptune’s orbital axis (both of which have periods of about 1.87 million years) has been identified as the likely source of Saturn’s large axial tilt (26.7°). Initially, Saturn probably had a tilt closer to that of Jupiter (3.1°). The gradual depletion of the Kuiper belt would have decreased the precession rate of Neptune’s orbit; eventually, the frequencies matched, and Saturn’s axial precession was captured into the spin-orbit resonance, leading to an increase in Saturn’s obliquity. (The angular momentum of Neptune’s orbit is 104 times that of that of Saturn’s spin, and thus dominates the interaction.)
So Saturn’s ’tilt’ is being driven by the coupling of its spin to Neptune’s orbital precession.
I’m sure there are many more to be found, now that the jargon mismatch has been found out. Now that we see that in astronomy it’s called ‘resonance’ while everyone else calls it ‘spin orbit coupling’.
Some Notes On Angular Momentum
The wiki on Angular Momentum makes it clear why this all matters.
They also have a less math heavy and less technical intro to angular momentum here:
In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system. The angular momentum L of a particle with respect to some point of origin is
L = r x p
L = r x mv
where r is the particle’s position from the origin, p = mv is its linear momentum, and × denotes the cross product.
The key bits are that it’s a conserved property. That means angular momentum doesn’t just go away. You’ve got to turn it into something else. That it is directly proportional to radius (distance from the origin) means that smaller things can have a lot of angular momentum if they are a long ways away. Yes, Mass (m) matters, but make that Radius (r) longer and the mass can be smaller with the same impact. So the sun has a whole lot of Mass, but it’s Radius of orbit about the barycenter is very small. Saturn is much smaller, but oh does it have a long lever arm to work through.
The angular momentum of a system of particles (e.g. a rigid body) is the sum of angular momenta of the individual particles. For a rigid body rotating around an axis of symmetry (e.g. the fins of a ceiling fan), the angular momentum can be expressed as the product of the body’s moment of inertia I (a measure of an object’s resistance to changes in its rotation rate) and its angular velocity ω:
In this way, angular momentum is sometimes described as the rotational analog of linear momentum.
Angular momentum is conserved in a system where there is no net external torque, and its conservation helps explain many diverse phenomena. For example, the increase in rotational speed of a spinning figure skater as the skater’s arms are contracted is a consequence of conservation of angular momentum. The very high rotational rates of neutron stars can also be explained in terms of angular momentum conservation. Moreover, angular momentum conservation has numerous applications in physics and engineering (e.g. the gyrocompass).
There is just no getting away from the need to conserve angular momentum. Period. Also notice the emphasis on ‘rigid body’. But the sun is not rigid. I suspect that is the great mistaken simplification.
So when the solar masses change their positions relative to the barycenter (center of rotation of the combined solar system and the center of the sun’s “orbit”) the sun suffers a change of Angular Momentum as it’s Radius (r) has changed. And that must show up somewhere.
The question now becomes “Where does it go?”…
As the coupling can, per all I can find, happen at any scale and distance, there are many places it can go. But there is one place it can not go, and that is ‘away’. I suppose it could even end up in subatomic spin (though I can’t imagine how) or out in the outer planets as orbital perturbations. My ‘best guess’ would be that there is some minor change of the flow of “currents” on the Sun. Perhaps the Solar Conveyor Belt slowing down is the consequence? Or some other modulation such that the Landscheidt predictions have a direct mechanism.
The simple fact is that the sun is about 1 % of the solar system angular momentum. The changes “out there” are far larger and more important than its whole package. And everyone is simply ignoring that.
Though I do note that this page on the formation of the solar system talks about angular momentum exchanges with some frequency:
Among the extrasolar planets discovered to date are planets the size of Jupiter or larger but possessing very short orbital periods of only a few days. Such planets would have to orbit very closely to their stars; so closely that their atmospheres would be gradually stripped away by solar radiation. There is no consensus on how to explain these so-called hot Jupiters, but one leading idea is that of planetary migration, similar to the process which is thought to have moved Uranus and Neptune to their current, distant orbit. Possible processes that cause the migration include orbital friction while the protoplanetary disc is still full of hydrogen and helium gas and exchange of angular momentum between giant planets and the particles in the protoplanetary disc.
For what it’s worth, looking at a google of “Solar orbital resonance” is more fruitful than the “spin orbit coupling” term, though it leads to a large number of articles describing the familiar cases such as orbital locking (The Moon always presenting the same face to earth).
has an abstract for a paper from Cornell University Library:
Orbital Resonance and Solar Cycles
(Submitted on 29 Mar 2009)
We present an analysis of planetary moves, encoded in DE406 ephemerides.
We show resonance cycles between most planets in Solar System, of differing quality. The most precise resonance – between Earth and Venus, which not only stabilizes orbits of both planets, locks planet Venus rotation in tidal locking, but also affects the Sun:
This resonance group (E+V) also influences Sunspot cycles – the position of syzygy between Earth and Venus, when the barycenter of the resonance group most closely approaches the Sun and stops for some time, relative to Jupiter planet, well matches the Sunspot cycle of 11 years, not only for the last 400 years of measured Sunspot cycles, but also in 1000 years of historical record of “severe winters”. We show, how cycles in angular momentum of Earth and Venus planets match with the Sunspot cycle and how the main cycle in angular momentum of the whole Solar system (854-year cycle of Jupiter/Saturn) matches with climatologic data, assumed to show connection with Solar output power and insolation. We show the possible connections between E+V events and Solar global p-Mode frequency changes.
We futher show angular momentum tables and charts for individual planets, as encoded in DE405 and DE406 ephemerides. We show, that inner planets orbit on heliocentric trajectories whereas outer planets orbit on barycentric trajectories.
That looks to me like it might be this paper:
Claims to find an Earth / Venus spin orbit resonance and that it influences solar cycles.
Has a nice long list of many known and some speculated solar cycles.
Shifting the search terms over to “Solar orbital resonance sunspot” you can even find an ‘electric universe’ explanation of what they think is going on:
OK, I’m not going to settle anything tonight. Just show you what pops up when using ‘resonance’ instead of spin-orbit coupling. They are not exactly the same things, but related via the angular momentum of the solar system.
And that is the whole point here. To show that the conservation and swapping about of angular momentum in the solar system is not a new idea. It’s fundamental. And it can not be ignored in explaining the behavior of the sun. In my opinion, the “simplified cases” that work well in describing a planet in the context of the sun are not suited to the sun itself. Why? Because it IS so massive, it is NOT a point mass, it is NOT a rigid body, the percentage of change of the radius of rotation is so large, and the external angular momentum that can act on it is so much larger than the percentage of the angular momentum in the sun now. Basically, all the things that make simplifications work for small planets far from the sun make those simplifications wrong in the context of the sun itself.
In the end, just recognizing that spin-orbit coupling is not just for subatomic particles is a big step forward. And it is not just the ‘spin locking’ of a moon to its planets either. Perhaps best put another way. The simple case that says A moon can lock to its planet implies that a nearly chaotic and constantly changing set of forces from ALL the planets acting on the sun will assure it can NOT lock, but will always be a bit ‘off kilter’… but those forces can move mass around inside the sun.