Transcription
Good evening folks. Today we're talking galactic astrophysics as it relates to the galactic current sheet. This year, we got the last piece of evidence needed to confirm that these central nodes of galaxies behave the way we expect. They noticed a magnetic reversal at an active nucleus in a galaxy, helping to confirm the Taurus jet and electric current sheet model.
Since our last summary video on the galactic current sheet physics, there's been a great deal of observations of its impact here in the solar system, how it's changing the magnetic and chemical composition of our local stellar neighborhood. And we've had even more observations of this spiral density wave electric field at other galaxies as well. We have seen more dust coming with the sheet in interplanetary space and at the sun, stuck to that electric field like dust sticks to your electrostatic duster in your home. There's more interstellar pickup ions (IPUs), more energetic neutral atoms than expected (ENAs), and magnetic pressure fronts encountered by the Voyager spacecraft.
What we're going to do now is watch parts of our last two summary videos on these observations and physics. The core evidence. There's only a bit of overlap between them. Hopefully, it's a good reminder, refresher, or maybe, if it's your first time seeing it, a good elucidation of what's going on here. Here we go. Let's see some of this evidence.
Starting in the realm of simulations of the fields, which when placing flows opposite and parallel, they want to form the ballerina skirt waviness that appears near the mid-plane in the newest galactic field simulation. Properly perpendicular to the fields, breaking up and down from the wave crests, lets you know they are solid in their theory. And of course, the newest electric field simulation of those parallel, oppositely flowing fields produces those endless ripplings.
In the realm of observations, these would include the gamma signatures where the current sheet crosses the higher plasma and dust density mid-plane, the galactic equator, or how they've known this cloud of dust and plasma is heading right at us for decades, and they just say it's a remnant of a past supernova. I love coincidences. Anyway, add on to the previous knowledge of the wave amplitude. We now also know the wavelength, tens of light years, putting us about 200 or so ripples out from the galactic center.
In terms of the electric field, it's another gem from the recent Voyager studies on the magnetic pressure fronts it's encountering. Also key is how it's driven by the rotation in the lab, in the solar system. Everywhere the central node wasn't spinning, the field would be flat. But you put a spin to her, and she happily abides by the physics of plasmas under the influence of that central node. This is the why to the ubiquitous observations, matching theory, matching math and simulations, and more observations: the rotation of the system.
Now to move on in asking what effect this impacting sheet has on the sun, we can ask what the sun, sheet, and interplanetary magnetic field (IMF) does to the Earth. In our textbook are numerous examples of how it forces not only the atmosphere but earthquake patterns as well. Since the book came out, we've seen a continued push from nearly the entire field of relevant journals to include the importance of this IMF to the geomagnetic indices most studied and used in these fields. In April, there was a surge in papers on this topic in a number of different journals. The future of space weather science has indeed been reshaped by our understanding of the geomagnetic importance of the sun's current sheet. The one not in print until June was also published online early in April. As someone who reads all that literature in this arena, it has been like watching a tsunami wash over the land, the importance of the interplanetary magnetic field.
And so now we wonder, what is a global magnetic disruption and a slew of electrodynamic effects of that current sheet going to do at the galactic level when it hits the sun? It is a galactic magnetic reversal, after all. But also, unlike the sun's current sheet, which has only minor plasma density shifts, the galaxy is dusty, gaseous, and not at all cleaned like the interior of our solar system. That plasma density of the galactic current sheet picks up the ambient dust and gas like an electrostatic duster in space.
The want for clarity is understandable. I checked the news concerning the revolution in galactic magnetic field theory and the existence of the galactic current sheet. It has been shared here in 19 different morning news shows over the last 22 months, with two more special videos. Now, that's a lot to remember, and a lot more if you have to go find them.
Just a few years ago, even though astronomers knew galaxies were threaded with magnetic fields, they believed them to be an incoherent mishmash of the fields, fueled by supernovae, randomly scattered about. But all that began to change as infrared and radio missions began returning better data on the galactic field, the central torus, and the cosmic jet. While the national labs were proving that cosmic jets could be created by the interaction of magnetic fields and electric currents, astronomers were seeing the large-scale structure of the galactic magnetic fields. They have studied from above and found the curved fields, just like in our sun's current sheet. They have mapped our own and others from an edge-on perspective, finding both the toroidal field shape and the central plane. They have found that magnetic reversals occur cyclically in the stream they see in the plane, indicating a sinusoidal pattern of magnetic field orientation. They've dug deeper using polarized light to reveal what proper motion sometimes cannot. And since the door to this new galactic magnetic field paradigm cracked open, a flood has begun. And no part of that flood has been more important than the discovery and confirmation, over and over, that the magnetic fields are streaming outward inside of the central current sheet plane. And these string-like features indeed go out throughout the mid-plane of the galaxy, where over 90 percent of the stars are actually found. There, in the plane, the field structure becomes more complex with criss-crossing returns and the data indicative of those magnetic field sectors throughout the plane.
Now, up close, we see the fine local detail of the interstellar fields. But perhaps this is actually too close for the moment. Indeed, they are modeling the galaxy as a scaled-up version of the solar system: electromagnetically powerful central engine with an ion wind, poloidal magnetic field structure with a central current sheet containing the magnetic fields. As you get further out, it ripples more and more, and the closer waves also have higher amplitude. This is all due to the bunching up, as you move out, of a much broader undulation close into the system. That goes for both the solar system and apparently the galaxy, where the wave amplitude follows that pattern, where a nearly 3x increase in that amplitude comes as you compare the interior to the exterior portions of the galactic mid-plane where the galactic sheet can be found. Recently, they even used gamma returns to catch nodes where the rippling sheet crosses the central plane of material and causes more interactions, as you might easily recognize if you can count. This is not spiral arm overdensities. We've never seen a galaxy with arms concentrically twisted that many times, especially on one half of the galaxy. Galactic nucleus is off the page to the right. Those nodes are indeed the sheet.
Now coming down to the level of the sun, astronomers' initial guesses were way off years ago in the mapping of local gas and dust, something where overdensities could be indicative of a nova remnant or the galactic current sheet wave. But scientists have run into problems, and none is bigger than the dust. It turns out that not only do we have a hard time spotting it, but it frustrates our ability to accurately measure the gaseous component of the sheet.
Now here's what we know. In terms of the waves emanating radially from the galactic center, there is a large wave behind us and one that appears to have begun engulfing our system now, which has considerable voids within it but is a large, coherent structure on the macro scale. We recently learned a lot more about the wave behind us, the Radcliffe wave, and while the scientists claim they can't figure out why it so nicely does a sine wave hugging the galactic equator, if you haven't slept through this video so far, I bet you've got some ideas.
So when it comes to this electromagnetic ripple, this curving wave, emits the waves, how do we characterize it? Well, to start, we'll go with the idealized plasma situation of a double layer, which the current sheet is. It is not sufficient to think of it as a single current sheet; the sun's isn't either. And the double layers we study in the lab and in geospace have boundaries of higher plasma density, like a ceiling and a floor, and the magnetic fields run within the room. That double layer, or tube, or sheet, or field between the layers. So forgive the crudeness of this, but picture an overdensity wave of gas, dust, and plasma, which has been attracted and stuck to the central current sheet and magnetic fields, double layer, through static and electromagnetic forces, stuck to both sides of it, creating the two layers, and then the actual current sheet and magnetic fields in the middle. The sheet will begin to affect a star system long before the crescendo, and that crescendo should be somewhere either in the interior of this sheet, not as soon as it starts to hit, or once that second layer has passed by. So the artistic liberty taken with poorly understood data notwithstanding, they really didn't get this image too bad, actually. Sure, they know a lot more about the Radcliffe wave now, and we are hoping to learn a lot more about the wave engulfing our system, although it is hard to see the forest, the entire forest, from within it.
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