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Friday, 20 March 2015

And Yet It Moves, Quite A Lot Like That

Is our Solar System a vortex ? No, says Phil Plait. "Err, not quite", says I.

If you've just wandered in off the street and have no idea what I'm talking about, here's the short version. Some time back, this gif and video were doing the rounds on the internet. Like a bad penny, they still keep turning up from time to time, with an astonishing capacity to go viral almost whenever they appear.

What Plait (quite correctly) describes is that the model of the Solar System this video promotes is utter nonsense. What I (also quite correctly) pointed out is that yes, the model is wrong, but the planets trace out helical paths through space even so. I even made a (much crappier) version of the gif to illustrate this. I gave the planets the correct 60 degree tilt relative to the direction of motion (which makes barely any difference at all) and put them in the correct order, just for the hell of it.

I've always maintained that it's that aspect of the video (showing our motion through space) that assures its popularity, rather than the alternative (wholly wrong) model it tried to promote. I did, of course, get extremely annoyed by the promotion of this nonsensical alternative model, but I wanted to make it absolutely clear that this helical-path business is perfectly correct.

I'm extremely pleased to tell you that I've just had a delightful conversation with DJSadhu, creator of the original video. I'll admit to a great deal of trepidation about even opening the email. After all, I wasn't particular polite in the original article, and I was fully expecting yet another angry email from a pseudoscientific nutcase. I get such things frequently enough that I strongly considered just deleting the email without even reading it.

Well, let me say this in no uncertain terms : I was wrong. Sadhu has listened to the critics and made a new video. Gone are the claims that the heliocentric model is wrong. Gone are the links to any alternative model of the Solar System created by someone who doesn't believe CFCs are the cause of the ozone hole. And gone are the links to the Fibonacci sequence as a fingerprint of God. What remains are some very nice graphics and a catchy soundtrack. The whole thing looks really well done to me.

When I watched it, I don't mind admitting that I was very pleasantly surprised indeed. I really can't find any show-stoppers with this at all. Really, if there are any inaccuracies in this one, I think this would be nit-picking.

As I pointed out in the first article, I couldn't see any hint of the Sun moving ahead of the planets, despite Phil Plait's claims (but keep reading) which would have been horrendous. Sadhu explicitly confirmed that to me :

"Again, the sun is not leading here, still not convinced it does. Although Bhat's paper put me on the "helical track", I do not take his "cone shaped model" as absolute fact... I've had of discussions with viewers, noobs, trolls, haters, lovers, and scientists, and I kind of doubt the cone shape model to put it mildly."

Seriously, what more can one ask for ? He freely admitted that his second video does show this Sun-leading model, but here he couldn't be any more clear : he's not trying to show that with this video.

Sadhu asked :

"And how come, even though the standard model is 'correct' and 'complete'... you had to come up with a completely new animation to show the old model is okay ?
Because there was no such video... and that's what I find annoying.
"Science" quickly jumps onto the "it's all wrong" bandwagon... and then you have to go and tinker to personally make the first "correct" version (oh the angle is a bit different)
The complete model should have been out there all along!!!!  

Noo, let's debunk DjSadhu, and then make the correct version - for the first time !"

I can see his point. There certainly wasn't a standard-model video out there - at least, certainly not one that's anything like as pretty or as popular. It would definitely seem very unfair to debunk the person who made such a successful video demonstrating (pretty much for the first time) the motion of the Solar System through space.

My response was to explain in some long-winded detail why the the standard-model video didn't previously exist, and what it was about the original that had got some people (myself very much included) riled up. I'll try and keep things a bit briefer here.

First, why there wasn't a video already. Any object moving on a circular path that's simultaneously moving forward must trace out a helical path. This ought to be incredibly obvious, but here's a simple demonstration you can try at home, provided you have at least one functional finger.

Hold your hand out and point one finger to the left. Now move your finger in a circle, and move your hand to the left. You'll see your finger traces out a helical path. There's nothing the slightest bit mysterious or profound about it - it's simple, basic geometry. No-one ever felt the need to make a video claiming "your finger is a vortex !"... err, well, on second thought maybe they did, but I'm not into that sort of thing, thank you very much.

Next. repeat the experiment but this time move your head at the same speed as your finger. The helices disappear ! Your head is now in the same "reference frame" as your finger - that's the heliocentric model, the standard diagrams of the Solar System you're probably familiar with. The heliocentric model is neither wrong nor incomplete, it's simply a choice of reference frame. And at this point, to demonstrate the fact that we've been aware of the motion of the Solar System for some time, here's the Galaxy Song again. Yes, I used this last time... but come on, it's a very good song.

However, while it may be completely obvious to me that the Solar System moves like this, it clearly isn't obvious to a lot of people. So I have to concede - empirical evidence demands it - that Sadhu's video (notwithstanding the alternative model, which we'll get back to shortly) is beneficial in that it does a good job of illustrating this fact.

The second point - it wasn't the video that got me riled up, it was what it was promoting. My response (shortened slightly) was as follows :
  • "First, you presented the idea of helical paths as though it were some revolutionary new model. You could have very easily checked with more or less any astronomer who would have told you that we already know this is the case. 
  • Second, I completely agree with Plait about Bhat - I think he's nuts. His document put me in mind of Moon landing conspiracy theorists and Hollow Earth believers.... Your claim was not, "hey everyone, in this reference frame we're moving on a helical path !" (which would have had people saying, "pretty neat !") but instead, "hey, this totally ludicrous model claims we're moving on a helical path, so I've overturned heliocentricism" (which has people thinking you're mad).
  • Third, you seemed to be strongly implying that you didn't believe the 60 degree tilt of the ecliptic was even possible, because you thought it would mean that sometimes the planets are moving faster than the Sun. Plait's analogy of swinging a ball on a string while walking down the street is correct - this poses no problem whatsoever for classical mechanics.
  • Fourth, you were claiming that in the classical model the planets should be eclipsed by the Sun once per year. This does not happen, simply because the orbits aren't all perfectly in the same plane. An alternative model is not necessary to explain this.
  • Fifth, I don't think it's fair to say that discrediting the other stuff on your website was not relevant. You made quite an explicit link between the motion of the planets and DNA and other organic structures. In effect, you claimed that your alternative source model provides evidence for a pseudoscientific idea about the Fibonacci sequence. That was never going to go down well."

Sadhu's response was pretty much everything I could have hoped for. I've re-arranged his response a little, for reasons that will become apparent soon enough. It deserves to be quoted at length.

"About two years ago I heard of this "Bhat model", the cone shaped, helical solar system. It fired up my enthusiasm and I started making these videos. Frankly I was a bit pissed about the 'standard model' (as you can tell by the claims in the first video), because it just did not show properly how things work. For me personally, the difference between a stationary looking dinner plate model and this dynamic, spiralling model was huge. So I made the videos, the first one (solar system) just showed this helical model, and the second one (our galaxy) showed this cone shape and the helical pathway of the sun, and lots of other debatable details. Especially that second video was reason for most resistance and criticism from the scientific community, but it affected how both videos were regarded.

Anyway, that was how it worked back then. Now, two years later, I'm certain of one thing: the huge difference between the stationary looking dinner plate model and the helical model remains.

As long as I leave out the wacky stuff, the cone shaped stuff, leave Bhat out, do not argue about the shape of the sun's path, it could easily be accepted.

So that is kind of what I decided, I want to make this "Solar System 2.0" video, with no outrageous claims, none of the disputable stuff, just the best representation of the helical model that I can make. And make it art.

The video does not claim that the heliocentric model is 'wrong', it puts it into perspective. For most people a new one. Also, the cone shaped stuff is not in the video, not important, and should certainly not ruin the message.

I'm not after words, but after images. So I left the words out. Vortex/helix, wrong/incomplete, all those terms are vulnerable ingredients in a video, and they are not the point !

The point is how people 'see' the solar system. Although the helical paths may have been known to astronomers and astrophysicists (and part of the public), what people 'see' when they think about the solar system is in my opinion incomplete."

It would be pretty damn tough for me to disagree with any of that. In fact, let me state it more explicitly : bravo, Sadhu, I salute you.

He did, however, make two statements I dispute - one is pretty minor, the other major but not as bad as you may at first think.

The minor point : "The only bold move I made was to 'blame' the upward angle in the sun's path for the difference between 90 and 60 degrees. "

I'd say the fact that the planets don't move at 90 degrees to the direction of motion is simply chance - they could be oriented at any angle. A more interesting, related point that someone mentioned to me elsewhere is that there's no reason the plane of the ecliptic (the narrow "sheet" in which the planets orbit the Sun) should always be at the same angle relative to the direction of the Sun's motion around the center of the galaxy.

That's a little bit complicated a statement, so probably an illustration will help. Here's what you might interpret Sadhu's video as showing (he confirmed to me that this is not what he's trying to show, however) :

Here the Sun (yellow circle) and the orbits of the planets (white lines) are shown at different points in their orbit around the galaxy (obviously they're not to scale). If they orbited like this, the paths of the planets would always trace out neat helical paths.

That might not be the case though. The plane of the ecliptic could keep the same angle throughout its orbit around the Galaxy.

In this case, the neat helical paths would only result at two points in the orbit (those at the extreme left and right in the above image). The result of the time there'd still be helices, but they'd be distorted.


At the other extremes (the top and bottom in the image), the planets would trace out something more like a flat, spirograph pattern than a 3D helix :


Which is correct ? Actually, I don't know. Or even care very much - and that's where Sadhu and I have a more profound disagreement. For me, the motion of the Solar System through space is neither very interesting scientifically nor philosophically*. For Sadhu, however, things are different :

* Personally I'd rather there was more interest in my hydrogen sky video or giant nuclear spaceship or exploding galaxy renders, which were far more interesting, labour-intensive projects.

"Yes, in my personal experience the helical paths, DNA, life, Universe is all connected. Hell, I would not be surprised if one day the discovery is made that the entire Universe is conscious."

Sadhu and I are never going to agree on that. And you know what ? That's absolutely fine. I have stated several times previously that I have no problem with people holding irrational beliefs, I don't see them as inherently wrong or amoral. What Sadhu is doing here is making a very clear distinction between his unscientific opinions and objective facts. That is commendable. If more people could do this, the world would be a happier place.


I still stand by my original article. I don't think I was wrong to debunk the claims against heliocentricism at all. As I said, the problems with the original video were minor, but what it was promoting deserved to be shot down.

Sadhu is no longer using his talents to promote anything remotely unscientific. True, he does still have unscientific opinions (and a brief glance at his website shows him to be interested in things I profoundly disagree with). Some of what he says is "disputed" I would say "no, that's just wrong" - but come on, there's no point being a jerk about it. For me to fail to publically acknowledge the virtues of this video, would, I think, make me a complete arsehole.

People, this should be seen as a win-win scenario. The essence of Sadhu's original video was correct, and he's publically declaring skepticism for the second one. His new effort has none of the quackery associated with the first. To me, that seems like the best of all possible outcomes. Demonising your opponents is no way to win them over - and sometimes, it turns out they were saying something valuable all along.


  1. I was actually one of the first folks who sniffed out Sadhu's original video and helped to make it go viral the first time around. While I used to major in Astrophysics, I didn't have too much of a problem with it not being perfectly accurate. That being said, I was happy that some folks (you and Phil in particular) made an extra effort to correct the animator on the actual science, and am pretty stoked Sadhu has corrected it as much as he has. That shows some real character.

    1. I agree that his response is commendable. However, I disagree that the issues in his first two videos were minor (as he and others say).

      There's a difference between errors of detail and fundamental errors. If you animate a bullet coming out of a gun with no spin, or even spinning opposite to the spin the very visible rifling would give it (which I've seen before), those are "errors in detail", that can be glossed over. But if you animate the bullet remaining in place after being fired and the gun spiraling towards the target, that is a fundamental "error in type". Most of his errors were like this. Bicycles wouldn't work, tops wouldn't stand up, we'd be in a universe without gravity, but have some other exotic force instead... His 3rd video has several errors in detail (the sun isn't rotating), but more importantly he animated it in such a way that the errors that stem from his fundamental misunderstandings / disagreements with the science can now be interpreted as errors in detail.

  2. Just like Star Trek, there are always a ton of white dots which I suppose simulate stars. There is no way that many single, planetless stars could pass by so quickly and so closely. Remove the starfield completely, and it would be close to realistic. Then diminish the "tails" in both length and intensity, on Sol and the planets, since they are currently overwhelming and only there for visual effect. IMHO
    I do appreciate the effort. Amazing video. Thanks.

    1. Umm.... gotta say that one confuses me.

      Stars look quite a lot like white dots in real life. Have a look at the sky sometime. What makes you think they are single and/or planetless, or passing by quickly and closely ??

      Of course the tails are only there for visual effect. That's the whole point.

    2. Rhys, I think Anonymous is referring to the way nearby stars whiz past the animated solar system. In reality, all nearby stars are ALSO orbiting the galactic center, and in the same direction as the sun. Sadhu's second video makes it look like every other star in the galaxy is stationary, and the sun travels among them.

    3. For the record, in my animation the stars don't actually move at all. Strictly speaking the Solar System does move relative to them very slightly, however this is negligible. Any appearance of them rushing past is an illusion.

  3. Plait in his article wrote that the sun "does in fact bob up and down" as it orbits the core of the galaxy, and we know that the tilt of the solar system is (currently?) 60 degrees or so relative to the plane of the galaxy, and that the planets spin around the sun, so it seems intuitive that the gyroscopic effect would be in play here. If this is the case then would it not make sense that the tilt of the solar system would change over time, that it would wobble? And if it did wobble as it moved through space would it not be forced to move from side to side as it moved up and down? It seems that the gyroscopic effect would cause the sun to essentially cork screw around the galaxy just as the video depicts.

    1. The plane of the planets around the Sun most likely does indeed alter over time. The planets do have an effect on the Sun and make it wobble, but not to anything remotely likely what's shown in the second video. There the Sun _and_ the planets were shown corkscrewing around some other common center, which is simply not the case.

    2. Can a rotating solar system act like and be acted upon like a gyroscope? This topic got me thinking today so I took a wheel from my bicycle and attached a rope to it. I spun the wheel and then caused it to orbit around a central point in the same direction of the spinning wheel. When I kept the wheel on a level plane the spinning wheel was very stable and maintained a vertical orientation, but when I caused it to move up and down I not only observed it's axis tilting but it also oscillated on the vertical plane, moving closer to me and then farther away. The combination of movements clearly resulted in a cork screw trajectory. Interestingly, when I caused the wheel to orbit in the opposite direction of the spin a violent flipping of the axis occurred. What I am asking is, can this happen on the scale of a solar system? It seems that, if the sun moves up and down relative to the galactic plane and it is spinning while on a circular course around the galaxy, would we not be able to observe the same motion as I did standing on the surface of our planet? What I'm suggesting is that the current tilt of the solar system is not static, but rather is fluid and is acting similar to a gyroscope. If this were the case, the axis of the solar system as a whole would precess as one unit along with the sun, and the angular momentum would carry the solar disk in one direction as the disk dropped below galactic equator, and in the other as it rose above, just as my Gyroscope did in my simplistic experiment.

    3. Well, probably... but to be blunt, the precise details of how the Solar System moves don't interest me.

      My point is only that the _entire_ Solar System moving in a corkscrew motion (like this : is not correct. Gyroscopic effects can't cause this (if you bicycle wheel IS doing something like this, I'd like to see it !).

    4. But what if it's movement in this way was a clue to proving the existence of Dark Matter, especially if, as theorized, that there may be large concentrations of this stuff in a halo surrounding the galaxy, then would it be interesting? And how about the Lense-Thirring Effect? Which bringsto mind something else Plait said in his argument about not having to account for the movement of the Solar system through space when calculating a trajectory to another planet, but I see the solar system as one unit moving through space, so we do not have to take into consideration the direction and speed of the solar system any more than we would if we were on an airplane plotting our course to the lavatory,

  4. Roger, your experiment with a bike wheel sounds fascinating, but I can't see it in my imagination. Where did you attach the rope to the wheel? I often use a bike wheel in classroom demonstrations of the gyroscopic effect because you can get a fair amount of angular momentum with them, especially older, heavier ones with solid tires. But if you're going to suspend or swing it on a rope, where you attach the rope makes all the difference!

    1. I did not have the time and materials handy to set this experiment up properly but if I had this is what I would do: I would affix a pole in the vertical plane, attach a lever to the top of the pole in a manner that would allow it to be rotated around an axis as the lever is used to move the wheel up and down. At the long end of the lever I would attach a rope or chain (or even better, a rod with articulating joints on each end) sufficient in length to allow a bicycle wheel suspended from its axle to have a full range of motion (slightly longer than the radius of the wheel). Then we spin the wheel, and using the lever, cause the wheel to orbit the pole and to travel up and down simultaneously. The combination of the spin, rotation, and alternating vertical movement will result in the wheel precessing, and the precession will cause the wheel to move horizontally. We should be able to witness a helical path of the wheel through space. The experiment should be attempted while spinning the wheel in the same direction as the rotation and again spinning the wheel counter to rotation. Be careful though, the counter rotating wheel may brake the machine if it is not sturdy enough because the wheel will want to flip over when when the rotation is accelerated sufficiently.

  5. My question is: How do we know the motion of the solar system around the galaxy? Isn't the timescale so great and the duration of our sample (the time that all human measuring has occurred, a few thousand years at most) so relatively brief, that we have a very incomplete picture of galactic movement?

    I guess I already know that, due to our short time of measurement, our models must necessarily be quite fuzzy.

    What I'd like to know is: are there techniques to overcome that limitation? Is there math that gives us a more accurate picture that our limited time can allow? Is it all just computer simulations?


    1. It's not easy, but it can be done. Fortunately it doesn't depend on waiting long enough to actually see things move - it turns out you just need to know the distance to nearby stars and their velocity towards or away from us. Distance is difficult to get but can be directly measured with parallax :
      Line of sight velocity is, fortunately, much easier to measure :

      Then there's some ugly mathematical jiggey-pokery which eventually gives you the speed of the Sun around the galaxy :

      So, it's not at all easy, and there will be some considerable error in all this, but it's possible.

      I don't know how much it will improve our estimates of the Sun's motion specifically, but for measuring the movements of stars in general in our Galaxy, the Gaia mission will be nothing less than revolutionary :

  6. "... Hell, I would not be surprised if one day the discovery is made that the entire Universe is conscious."

    Got news for you Rhys (if you haven't figured it out by now), *we [humans] are the Universe manifest conscious, getting to know itself.*
    So in a way, the Universe is conscious and we are [so far as we're aware] the only senses it perceives itself through.
    That doesn't imply any sense of superiority or selfish arrogance to think *we are the only ones.* It merely is a statement of present observable fact.

  7. The existence of conscious humans doesn't have anything to do with the whole universe being conscious. That's like saying that the existence of jelly means the entire Universe is jelly. You could say that we are the conscious component of the Universe, just as a bowl of jelly is the Universe's jelly component, but it's not the same as saying the whole thing is conscious (or jelly, or conscious jelly).

  8. Hmm... I think you may be having two different conversations. The jelly analogy breaks down because the jelly component can't observe the rest of the universe, so jelly isn't a way for the universe to experience itself. Human consciousness IS (a part of) the universe able to observe itself in a way not possible with rocks, stars, and jelly. If I understand WorknPlay's point, when it's a universe we're talking about you can't really separate the part from the whole, because you can't get outside the universe and look back at it. Like part of a glass hologram. The universe observes itself through human consciousness, which emerged from and is integral with, that same universe. This doesn't necessarily imply anything about the non-human parts of the universe being conscious, just that "as a whole" it is now self-conscious, self-aware. I hope I'm not putting words in either of your mouths, just trying to explore where my viewpoint aligns (or doesn't) with both of yours.

    1. "The jelly analogy breaks down because the jelly component can't observe the rest of the universe, so jelly isn't a way for the universe to experience itself."

      Well, no, it's an analogy. Jelly is a component of the Universe just as consciousness is a component of the Universe. We don't say, "heck, I would not be surprised if the whole Universe is jelly !", so why should we say, "heck, I would not be surprised if the whole Universe is conscious !" ? Sadhu's point was that it is the entire system of the Universe which is conscious, not some small component of it - and that's what I don't agree with.

  9. How does one know what it is like to be conscious? How would you know self without other? The difference between hot and cold? Wet and dry? You cant have the one without the other. You wouldn't know self without first knowing that there is someone other than the self . You couldn't experience hot unless you experienced what cold was like. You cant have the one without the other. Its transactional, its like buying and selling. You cant have a buyer without a seller nor a seller without a buyer. They go together. Wouldn't you agree that before we existed the universe was working in harmony to create the planet we now reside on? Just like an apple is the product of an apple tree wouldn't you agree your a product of this universe. In other words you are the universe. If the Apple is systematic of the apple tree then we are too. So now that im done going in circles like djsadhu's. No offense loved your presentation its a bit rudimentary but your certainly on to something. And as for your comment on the universe being "conscious" well of course ;-)

  10. Hey Mr. Taylor, I wonder if you can help me with a question. When I googled 'direction of Sun's path in galaxy' this post came up. I'm trying to confirm or correct an idea I've gotten into my head; from fiddling with Stellarium it looks like Earth will be lined up (between the galactic plane and the Sun) with the Sun and the galactic north pole this (2015) Oct 6. In other words it looks like we will be under the Sun on our way back up in our yearly path above and below the Sun in the galaxy.

    1. I am not quite sure what you mean. Could you post a screenshot ? Do you mean that we will line up with the Sun and the center of the galaxy, or something else ?

      Sorry to take so long to respond, I'm on holiday.

  11. I made a quick post on my blog with the screenshot....I can't figure out how to get the image into this comment box. Now if this link will work. Thanks for responding! I'm trying to make sure I've git this picture right- that Earth is between the Sun and the galactic plane, at the bottom of the cycle going up and down around the Sun in the galaxy.

    1. Thanks ! I'm not familiar with Stellarium so I used Microsoft's World Wide Telescope instead. It's nice because it allows you to use, galactic, equatorial and/or alt-az coordinates.

      As far as I can tell there's no particular significance (in Galactic terms) about October 6th. There is an alignment between between your meridian, the pole, and the Sun at that time, but the meridian depends on your longitude; I guess you'll be at 4 degrees 30 minutes west. From anywhere else there's no alignment.

      For example here's the view from Prague :
      The green is the alt-az coordinate system and the blue is the Galactic coordinate grid.

  12. Thank you! I will study this and see if I can figure out the correct date.

  13. Hi Rhys, being a DJ Sadhu fan myself, I like your article on the topic. I found this page via a link mentioned on a recent forbes article titled "How Fast Does Earth Move Through The Universe?" which i saw in a flipboard magazine. What got my attention was your gif animation showing helical orbits. Interesting that you are an astrophysicist with CGI experience. If time permits, do read my article on some topics which might interest you :
    You might find the writing style familiar, although more blunt :D

  14. "However, while it may be completely obvious to me that the Solar System moves like this, it clearly isn't obvious to a lot of people."

    It wasn't obvious to me. I've always been taught the Earth's path through space is an ellipse, and didn't really think more on it, until a few days ago when I was thinking about time travel. I suddenly realized that if I zipped back in time one year, the Sun and its planets would have moved on without me. If the orbit was truly an ellipse, I would be pretty damn close to my original spot. So I went googling, thinking "surely someone smarter than me has thought of this", and found your page. But many other resources online still insist that Earth traces an ellipse through space, even in textbooks.

  15. I came to a similar model of the solar systems movement on my own without understanding any of the science. I too took this motion from the shape of the spiral and the DNA strand. It seems to me that all motion is a sort of wave not really a straight line for the same reason. When we view a coordinate system it is only 2 dimensional with a two dimensional line and point system. Seems logically as we are 3D that each point is really a sphere and each line is this a spiral shape moving in a direction. When I understood these concepts all science made sense and I independently understood science and math stuff that I could look up and confirm. I think if this video was any indication that Astroscientists should make more visual models, they say a picture is with a thousand words so videos must be worth thousands of words.