09:42:35 And our last talk of the morning is given in lieu of Chris Jones by his young colleague, you can sign. 09:42:53 And you can did the PhD at Maryland has held various postdocs and has worked on various problems and nonlinear dynamics and vortex dynamics and turbulence, and he's going to talk about zonal flows of Jupiter in light of the Juno mission so you can please 09:43:17 let me share my screen. 09:43:26 Can you see the slide the title slide Yeah, sure. 09:43:30 So, well as Patrick mentioned, this is actually Chris talk. So, I'll try my best to reverse engineer what he wants to say from the slides. 09:43:47 I will start with a picture that you probably have seen a few times now, which is the Jupiter some flow pattern on the surface, and for some reason he's been rotated 90 degrees so movies at the bottom. 09:44:01 But it's okay. 09:44:03 And this has been measured with high resolution very, Very good accuracy, from previous mission dating back to the late 70s early 80s by the Voyager in other missions in the main point that I would like to draw attention to is that this pattern, the anti 09:44:23 symmetric property of this pattern. So at the north, you have strong Eastern jets, Eastern eastward kit and then in the Soviet strong with with Jeff and we will come back to this later. 09:44:36 And these days are usually mostly limited within the plus and minus 60 degree latitude. 09:44:45 In, we now know that beyond plus and minus 60 degree latitude, these jets transition to what it says. Thanks to the original mission. 09:44:54 So the, this is a beautiful picture, produced by a journal that shows the north pole of Jupiter we see this array of what is this. 09:45:05 In back in 1979. 09:45:09 He also suggested that these Jupiter jets may take the form of a PV staircase in. 09:45:21 And as far as I know, is what is at stake age has been found in show models, but for deep connection model is less clear example, these are these are two examples of connection trippin locating shell fluid in, but this has been fed relatively thin show 09:45:45 the inner radius to the outer radius ratio is point nine. 09:45:50 And these are some of the earliest simulation left one is by Hempel at all in 2005, this is what's next simulation. 09:45:59 And on the right we have been an elastic simulation which is an approximation to decompress donation have good boundaries. 09:46:07 And recently introduced a 1500 boys and updated more high higher resolution simulation using an elastic approximation, and then I think Peter, Peter he talks about his work. 09:46:21 Last week, where he used this a series of paper published by Peter and his collaborator, using the new generation of Jupiter GCM. 09:46:31 And if I understand these simulations correctly I think they all produce more projects. 09:46:38 Roughly resemble the pattern that you would see on Jupiter, but whether they are PVC staircase is less clear, and as Peter told to us he saw hypos take a structure in the simulation. 09:46:52 So at least I believe in this consideration, the staircase structure it exists, it's not as clean as sharp as this. 09:47:02 So, well so much for force surface pattern. What what we know is really about is to determine whether these jets, how deeply steps extend to the interior. 09:47:17 So back in 1995, the Galilean mission drop a probe into the atmosphere of Jupiter, trying to estimate the wind profile as a function of something. 09:47:33 And this is the results that the props and back. Though it. It dive into the chemistry of Jupiter in bravely text data for by an hour before we die, and it's what they send back. 09:47:48 And I think it's surprising at that time that they find out that the wind speed actually increased with Beth, and then it stayed, more or less constant. 09:47:59 And this is probably I believe the first claims of Jupiter wins believe, probably can observe, other servants. 09:48:09 However, because they don't they just drop a probe, so it's just a single letter to the job, cover it and then they go along a straight line. 09:48:18 And so it's only a single letter to you and and also where we only had an hour of life, fly, so it can only reach about 20 bar which is probably 160 kilometers. 09:48:32 In, after that, we don't know was, how was the structure of the velocity. Velocity beyond 160 kilometers from from this mission. 09:48:42 So, after many years to know is trying to answer that question 09:48:50 in a way that is trying to do it well there are two ways in the try to do it. The first one is by measuring the grip grip of gravity. Gravity few of Jupiter. 09:49:03 And then the second less direct method is to look at the secular variation of the magnetic field. So let's take a look at the first method first. 09:49:13 If you're standing outside Jupyter, then the competition potential expand in terms of the frequent Mannix expression written down here, expansion coefficient or this jnm. 09:49:30 And we will mainly focus, where we will only talk about jn, and we only talked about an M equals zero, and we call those coefficient jn, just to you. 09:49:42 And we mainly focus on the odd odd coefficients which those values are shown here they are, but they are small, but they are non zero, and then there's significant this because this coefficients this jn to efficient. 09:50:03 planet. They are related to the density of authentic food is integral. So if that's the robot and the computer cynical you get this script expansion very efficient. 09:50:11 And if the density is symmetric about the equator so if it is not self symmetric symmetry. Then, Jay. 09:50:26 And since the suffragettes. 09:50:28 And this metric me believe this anti symmetric, or at least non symmetric some objects will protect the density, which will give us in non symmetric role prime. 09:50:43 And this will show up in in this odd JJ 335 and seven. 09:50:50 And so, if we can somehow construct. Well, if we can somehow link this empty symmetric density to the solar jets, then we can get some information about the soldiers from this coefficients and. 09:51:09 And so we did, we need and we did an equation that the towers that tell us what row primary be if we, if we have an added measure component in the velocity and different possibilities and the simplest one is the femoral when equation which was written 09:51:27 down here. 09:51:41 So in here feed as they are useful usual polar coordinates the polar angle in the political direction, omega is the rotation rate of Jupiter in row prime is to population density. 09:51:46 We believe this is realistic in the model that we are going to consider is, is mainly due to the aunties metrics and we'll get you is the velocity that some of your lasting. 09:51:57 And so if we can construct a model for this velocity, new, we can calculate what kind of destiny professionally produced will prime. So we can plug it into this integral here, and we can calculate the port jn, and we can compare that to observations. 09:52:21 And hopefully for iterative scheme and optimization method, we can find a new that can produce a role prime, which leads to some jn that matched observation, the best. 09:52:35 And that's the procedures taken up by Casspi at all. 09:52:55 In 2018, and what they are taking for the model for you is like this. They take the pattern of the summer just on the surface, And then extend it inwards along the direction that's perpendicular to the, to the rotation excess of Jupiter, they multiply 09:53:05 And then they ask, what kind of qR will produce a jn that match. When we produce a free thought jn that mentioned observation the best. 09:53:19 And we've all going through the details. 09:53:22 I'll just tell you the results, we found that if QRD case to almost zero and the wrong with several thousand kilometres, let's say around 3000 kilometres, then they can pretty much get some tea and this this match the match observation within, within 09:53:43 hours. So from that they concluded the, the Jets. 09:53:47 Extend actually quite a bit into the interior of the, of the planet. 09:53:54 The radius of Jupiter is 770 thousand kilometres. So with extend to about 4500, kilometers so it's about point nine five, the radius of. 09:54:08 And this is much much deeper than the weather layer. 09:54:13 So this is the paper by Casspi at all. 2018. 09:54:25 But this is only one possibilities, it turns out 09:54:24 the thermal radiation which can be about 2018 use. 09:54:29 This is the standard textbook. 09:54:31 The movie equation. And if you think about this. 09:54:34 If you put up the density, then the gravitational field will be perturbed, too. So there should be a, an extra time anymore, to prime. 09:54:47 And if you put that term in, then you get a more complicated equation, but you can carry out the same procedures we can, no constructor will all see you and solve that complicated equations for all prime and once again calculate the otter chains in this 09:55:02 work. This paper Kong without penis 2018 need, and they use what they call the thermo gravitational being equation, so we include a term that's described to protect the gravity field. 09:55:20 First they try a similar procedures like the Casspi at all, 2018 to construct a model with deep jets, we've got the key function and they optimize it and they found that the Jets. 09:55:32 This goes to about, again, doesn't get on with this. 09:55:35 But in addition to that, they also found that you can you can actually produce some odd chant and match observation, with no deep jets. But, but if this is conducting flow. 09:55:47 So this is a slow conducting flow. 09:55:50 And this can actually give you some gn that match, based on was pretty well. 09:55:58 So, um, so the idea that the the soldiers is steep is only one, one possibility. So, but, but this flow here. 09:56:08 It's not, it's not us traffic we believe that the project is a rapidly rotating sphere. So we believe the flow is should be mostly Jones topic. So you expect it will variation along the rotation axis. 09:56:29 But this obviously is not what I saw. So I, I personally would think that the deep jet scenario is, is more plausible, but they could be other possibilities for example in the air cargo that we don't really know what the interior condition is. 09:56:43 So, this is, this cannot be ruled out. 09:56:47 And so this is how you use the gravity field to deduce the structure of the summer jets. 09:56:56 And I'll just quickly mention the other way to do it, which is looking at the secular variation of a magnetic field. 09:57:04 It just means that that where the magnetic field varies on the various low scale. 09:57:25 Like, bow. Well, they did. If you compare the observation that 1973 to what we observe now you can see say this spot treat just a little bit. 09:57:21 But the suggestion is here is that this drifting of is structured in the medical field is actually induced by the direction of the summer jets. 09:57:32 And this paper more 2019 they take up this proposal in the construct of flow model, again, based on what you observe at the surveys and extended inside. 09:57:44 And they found that if you extend this flow down to, once again, 3000, kilometers. And then they watch the magnetic field. Bye, bye This is model velocity feel they can get the pattern to match, they back periods observation, using the model, and they 09:58:05 can get what what we observe today. And so this provide in other evidence for for deep Sumerians in Jupiter. 09:58:17 So if you, if you believe the just do go down to 3000 kilometres. The naturally. The next question is to ask. So, why 3000 kilometres what what stop them there. 09:58:34 In for that. I need to go. 09:58:38 I need to tell you a little bit about the interior structure of Jupiter. 09:58:42 So tribute as many made up of helium in hydrogen in on the surface hydrogen is in this particular form so it's not conducting. But as we go deeper and deeper temperature and pressure increases and the hydrogen becomes conducting it becomes metallic hydrogen 09:59:00 is conducting, and is the connection is the motion of this metallic hydrogen that produce the magnetic field. 09:59:09 And interestingly that the conductivity of Jupiter. 09:59:12 Well, if you if you have a core of competence to it, and then you have the non converting basically solid, mental, but Jupiter is just a ball of fluid and conductivity various continuously with death like this picture here. 09:59:28 This is a theoretical calculation of the electrical conductivity interpreter, based on 09:59:36 quantum quantum calculation. 09:59:39 So inside. Okay, here is the origin and then as we move along this direction this is it's the base. So, inside the conductivity is fairly high close to the value of score. 09:59:54 And then at some point, you start to drop, because those metallic hydrogen is turning back to molecular hydrogen it drops. But the point is it dropped continuously, and it dropped, very quickly. 10:00:07 So there's a semi competing region, and then people and then after that this is just not conducting 10:00:14 in this theoretical study shows that the transition from conducting to non conducting, that is the location of the semi competing region is always around several thousand kilometres. 10:00:29 So it just happens to be where where the Jets. And so there are speculation that may be is the magnetic field that the stock the chance. 10:00:41 We don't know how 10:00:45 And, well, that's one possibility but there's another one that is not involved the magnetic field. 10:01:01 Another possible way to stop the Jets from getting any deeper, is that well as the Jupiter is made up of helium in hydrogen, and it's something if the temperature and pressure is just right, that somehow helium in hydrogen becomes miserable. 10:01:12 So the helium you separate the hydrogen, what we now call helium green. 10:01:18 So the heavier helium you fall down and form a stable layer, like like this picture here. So this is the molecular hydrogen. Here is the metallic hydrogen somewhere in between you have this labeled stable helium layer. 10:01:35 And this way in this way of the radio velocity is mostly. Well, this week in flow is is on the surface. 10:01:45 So, this could be another reason why they buy the Jets stop here. 10:01:52 And these two mechanism of stopping the Jets will be limited in these two different structure. 10:02:03 So on the left is the one is, there's no stable air. We believe the, the Genesis being stopped by the rain stores from the magnetic field. 10:02:27 free to do what they want to do. Inside here, the medical field stopped the Jets, and because of geography. 10:02:33 Not only inside the semi competing region, but also its whole column here. There's no differential rotation. So for this picture here, you have a deep, get around the equator, and then a higher led you to just shallow. 10:02:50 And there are some evidence that the highlighted agents are actually not quite the same as the equatorial GNC, go back to this picture here. 10:03:06 But you can you can argue that them this chance to actually looks more like like this staircase one shop at a peak and then probably at the bottom, where the one that's close to the equator, they don't look as much like the TV stick a structure. 10:03:20 So there's there is some evidence that maybe they get near the equator is not exactly. This is. 10:03:35 The other picture that we that the image. The dress is being stopped by by the stable layer. You look like this. 10:03:45 So what the staple a adults is inside we have is conducting fluid rotating in connecting producing the medical field. 10:03:56 But whatever the velocities here is being cut off from our society conducting life. So the stable layer, actually the couple. The foot inside, from the outside. 10:04:09 So now the Jets, where they this jazz can always go deep and now the highlighted you just can go to two. 10:04:17 In, we we don't know which which one is the correct picture, and these are just two proposal. 10:04:29 So just. 10:04:32 But this is just what I told you. 10:04:35 So here's the conclusion so we have not we should not look at the gravitational field of Jupiter, and it's possible to use that to reduce the extend way to just get go into the interior of Jupiter. 10:04:54 In the second iteration of the magnetic field also mentioned Petrillo can provide for the evidence of deep, the deep jet scenario. 10:05:00 In why the jet stop there is not known, possibly due to democratically just because the semiconductor region is right at where the Jets die and other possible reason could be this stable layer because of this helium, rain, and there are still a lot of 10:05:27 unknown here and there will be a lot of exciting research opportunities as Chris said. Thank you very much. 10:05:32 All right, thank you very much for an interesting talk and for doing this on short notice. 10:05:39 Questions for you can. 10:05:42 David Rachel. 10:05:44 I can see you after a while, 10:05:49 but I wanted to know if there, if there was a stable layer at this depth. 10:05:56 Do you think it's the top of it would be dynamically active is or is it so do you think it's like a bottom topography Could it be, what what's your view of the dynamics of of this interface between say the bottom the fluid. 10:06:14 The active fluid in the stable air 10:06:18 is modeling, what would we use. 10:06:25 What is everybody's case. Nobody knows But okay, from the modeling point of view, we're not going to actually put a stable layer there. We are going to manipulate the temperature. 10:06:38 the dynamics from there. Okay. Yeah, so, so for this Jupiter simulation we need to prescribe a equilibrium temperature which drops from interior high temperature interior and then too low to measure outside. 10:06:52 So this is our basic state. 10:06:54 So, we will manipulate this may SpaceX day so they reproduce a stable a for us. 10:07:00 And they already people doing that actually. 10:07:06 Thank you. 10:07:07 Thank you. 10:07:08 Okay, Brian. 10:07:11 Yeah, the, the whole word jets are stabilized by beta, the equatorial jet is in a region. 10:07:20 Beta zero. So, or were they were they were the strict polar regions have beta zero. So there's no stable Jetson the polar regions and beta is very large around the equator so that's the reason that you get that very large table jet so if you do the whole 10:07:39 problem on an equatorial beta plane, rather than a middle attitude data plane, you find oil jets which look correct. 10:07:48 Thank you. 10:07:50 Okay, I think, I'm next. So, I'm just interested in you, in the magnetic field effect on the story. 10:08:02 Is it a direct effect of the mean field or is it a modification of jet production due to magnetic fluctuations, which may then either produce a mag Maxwell's stress, which works against the Reynolds stress or D phase, the Reynolds stress. 10:08:25 In other words, there are many possibilities for for a magnetic field to screw up zonal flow production and it doesn't have to be a direct effect of a strong field is you're completely right into the honest and short answer is I have no idea. 10:08:45 I don't know it, like I said people suggest that the magnetic view is recent it's topical purely based on the coincidence of the numbers. 10:08:58 The weather is true. 10:09:00 All right, thank you and we'll give the last word of the morning to Professor huge. 10:09:16 You can you mentioned all the, the jets and things that low latitudes and mid-latitudes would you like to say anything about the water sees at the pole out what what's the current theories about or experimental data that how deep those go down Do you 10:09:25 know. 10:09:26 No, I don't know, I think you've done some work on how, what is this chain change to Jess, let's move. Oh, yeah yeah i mean that that's in a box, I just wondered about. 10:09:33 I was asking about the real thing, whether whether there was any, any day to, I guess, or anything, anything like you were doing for jets whether you could say anything. 10:09:51 Any, any quantitative data about the borders of spy I could be wrong, 10:09:58 but the bonuses are fairly new, we don't see it until until it you know picture a few years ago so, yeah. 10:10:07 Okay, thanks. 10:10:09 All right, let's thank you can again for a great talk, and they're under difficult circumstances which are interesting. 10:10:19 And I think that concludes our agenda for the day and, indeed, that concludes our agenda. Formal talks, and we enter a new phase of the program, Thursday at 9am, I believe. 10:10:38 When Pascal will lead her group on interfaces. So if you're looking for a change of pace, you'll get it. 10:10:47 So, hope we see you all then.