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I have watched the following video (How Earth Moves by Vsauce) regarding how earth moves:

Here are some screenshots:

Text

Text

I have some questions:

  1. Does the earth spiral around the sun's path as it is shown in the video (exact time is 19:49) and screenshots? Is the spiraling movement caused by sun movement (on its path shown above) where the sun is dragging the earth (and other planets).
  2. Does the earth go in front of the sun then back, then fourth and back like it is shown on the video? I see both the sun and earth racing with each overtaking the other over and over. Is this assumption true? In this manner, would earth, at one point in time, be closer to the destination where the solar system is heading (I think they call the destination Vega) than the sun?
  3. I am working on a poetry piece. If I mention that earth and sun are locked in a never ending race with each taking the lead (earth moving in front of the sun's path / winning) and earth actually dropping out of the race (spiraling/moving out the race and falling behind), that they are destined to never meet (collide), would I be correct?

P.S. My knowledge of astronomy/physics is very limited. I have tried my best to be as clear as possible. Sorry for any confusion. Thanks.

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    $\begingroup$ It is incorrect (It's not even a theory, it is a known falsehood). See the other question. In the picture that happens, but this is a consequence of the choice of frame of reference, in other words it is not a physical fact, but an effect of how it is drawn. $\endgroup$ – James K Jan 5 at 7:16
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    $\begingroup$ It's a straight dupe "1. Is the 'heliacal model correct'" is the same question as "Is the heliacal model wrong". Heliacal model = Vortex theory, they are the same thing. $\endgroup$ – James K Jan 5 at 10:19
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    $\begingroup$ @uhoh I appreciate your interest in the question, but you're emphasizing a distinction which the two video authors ignored. $\endgroup$ – Mike G Jan 5 at 14:01
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    $\begingroup$ @JamesK Thanks for the comments. I just started reading them a few minutes, ago. My knowledge of physics is very limited. My question was regarding the spiraling movement of earth around the sun's path in the video. I posted some comments on uhoh answer to clear things up. $\endgroup$ – knowledgeseeker Jan 5 at 14:27
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    $\begingroup$ Hi, knowledgeseeker, and welcome to Astronomy Stack Exchange. We prefer that askers edit their initial posts rather than asking them again, for the sake of clarity. I've deleted the second version of your post but edited the salient details into this one - feel free to edit again if I've missed something or made an error. $\endgroup$ – HDE 226868 Jan 5 at 16:15
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Does the earth spiral around the sun's path as it is shown in the video (exact time is 19:49) and screenshots?

The Earth does spiral around the Sun's path, but not quite as it's shown in the video.

  1. It isn't clear if the video accounts for the 60 degree tilt of the Solar System with respect to the galactic plane.

  2. The sizes and distances are not to scale. The Sun and the Earth are depicted far too large with respect to their distance from one another.

  3. The relative motion is not to scale. The distance from one side of the spiral to the other side should be about 2 AU, or 3x10^8km. But the Sun is moving at about 200km/s around the galaxy, or 6.3x10^9km per year. So the distance between two consecutive spirals should be more than 20 times the distance from one side of the spiral to the other! This can be visualized as an overextended slinky.

Is the spiraling movement caused by sun movement (on its path shown above) where the sun is dragging the earth (and other planets)?

No, the Sun's and the Earth's mutual gravity cause the Earth to rotate around the Sun. The Milky Way's gravity causes our Solar System to revolve around the galactic center. The Sun and the Earth are on the same plane and moving through the galaxy together. The Earth would still rotate around the center of the Milky Way if the Sun magically disappeared.

Does the earth go in front of the sun then back, then fourth and back like it is shown on the video? I see both the sun and earth racing with each overtaking the other over and over. Is this assumption true? In this manner, would earth, at one point in time, be closer to the destination where the solar system is heading (I think they call the destination Vega) than the sun?

If you consider a plane tangent to the Sun's velocity vector, then the Earth will pass across that plane twice per year, appearing "in front of" and then "behind" the Sun. This is simply a geometric result since the Earth and Sun share another plane. I wouldn't call any future position of the Solar System a "destination" without evidence the Solar System was sentient, but I am not a philosopher.

I am working on a poetry piece. If I mention that earth and sun are locked in a never ending race with each taking the lead (earth moving in front of the sun's path / winning) and earth actually dropping out of the race (spiraling/moving out the race and falling behind), that they are destined to never meet (collide), would I be correct?

We haven't ruled out the possibility that the Sun may someday envelope the Earth: What will "the Earth being consumed by the Sun" look like?. Also, the Earth isn't likely to leave its orbit before that time, but the Solar System is chaotic on long time scales. However, your poem would be consistent with current models, and we (humans) don't conclusively know how the Solar System will end. So my two cents is that your poem doesn't contradict modern astronomy. Besides, what's the use of a poetic license if you don't use it?

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    $\begingroup$ Thank you so much for the valuable information. I appreciate it. I have a couple of questions. You don't have to answer them if it is a bother. You said that if the sun disappeared, the earth would still rotate around the galaxy. With the absence of the sun, will the earth stop revolving on its own axis? Also, is there a possible non-extinction force that would make the earth stop revolving on its own axis over time. Thanks. $\endgroup$ – knowledgeseeker Jan 11 at 5:44
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    $\begingroup$ @knowledgeseeker The Earth would continue to rotate around its own axis without the Sun due to conservation of angular momentum. Tidal forces are causing the Earth's rotation rate to decrease, but most astronomers agree that the Earth won't cease to rotate until it ceases to exist. Related: astronomy.stackexchange.com/questions/40768/… $\endgroup$ – Connor Garcia Jan 11 at 17:00
  • $\begingroup$ @Connor Garcia: VSauce states that the sun is heading for the Great Attractor, in your answers to the questions of knowledge seeker you state that the sun is heading for the black hole in our galaxy. I wonder what is the case and why. See also youtube.com/watch?v=rztU-jnmcdg for a stunning animation of magnetic directions in the observable universe. $\endgroup$ – A.C.M.Meijer Feb 10 at 0:23
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  1. Is the helical or spiral model shown in the video real or just a theory.

It's sort-of real but not necessarily the way it's shown. The Earth orbits the Sun in roughly a circle, and the solar system is moving relative to the center of the galaxy in roughly a straight line (on the time scale of thousands of years and more) but those squiggles shown representing the motion of a point on the Earth are horrible!

The graphic makes it look like it has convex and concave points but that's only because the scale is messed up by ten thousand times! For more on this see this answer to Why is there no concavity in the orbit of the moon around the Sun? A sampling:

Here's a video and a GIF from this answer

Read more about the tools used to make this video in this answer.

GIF below: Screenshots from the YouTube video lagrange points animation.

[Screenshots from the YouTube video lagrange points animation


Bad VSauce! Naughty VSauce Not as Bad VSauce! Not as Naughty VSauce

Left is messed up, however right is roughly correct. (click for full size)


  1. In the model described (even if it is disproved), does the earth go in front of the sun and then back, then forth and back like it is shown on the video? I see both the sun and earth racing with each overtaking the other over and over. Am I seeing an illusion?

When motion is involved, it can look very different depending on what frame you are in. It's not "an illusion", instead it's just that motion has to be definied relative to something and it looks different depending on what frame you choose.

Richard Feynman mentions the ball in the wagon. While it's not the same scenario it may help us to start thinking about what "moves relative to" means.

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    $\begingroup$ Am I right? I am working on a poetry piece. If I mention that the earth and the sun are locked in a never ending race with each taking the lead (earth moving in front of the sun path / winning) and earth actually dropping out of the race (spiraling/moving out the race and falling behind), that they would never meet, would I be correct? $\endgroup$ – knowledgeseeker Jan 5 at 14:16
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    $\begingroup$ @knowledgeseeker that's different than the question that you've posted but it's close enough that I can coment. The Sun and Earth can be though of as moving in spirals; they move in circles around their common center of gravity, and if you count the solar system's motion in the galaxy each of their paths are spirals. But hopefully they will continue to spiral for a long time and neither will drop out! $\endgroup$ – uhoh Jan 5 at 14:21
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    $\begingroup$ @knowledgeseeker Your question was quickly closed because somebody proposed you were asking something else, that you clearly weren't asking and decided not to give you enough time to reply. At this point if you would like others to have a chance to answer, it's best if you make an edit to your question and add "My question was regarding the spiraling movement of earth around the sun's path in the video." as you wrote in the comment. That will trigger the reopen process and five more votes will set things back to normal. Normally things are pretty smooth here, but once in a while this happens. $\endgroup$ – uhoh Jan 5 at 15:51
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    $\begingroup$ @knowledgeseeker motion is relative: from the point of view of one object moving with respect to the solar system, the sun and Earth can appear to be moving on helical paths. From another, they could be moving within a plane, each moving ahead of the other. From a rotating frame, they would appear to be spiraling around the observer. None of these are very useful for understanding the physics of the motion, for that you generally want to use a frame of reference that moves along with the system, where they move elliptical orbits around each other. $\endgroup$ – Christopher James Huff Jan 5 at 22:03
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    $\begingroup$ @uhoh Thank you so much for all the help above and here. I appreciate it. I have edited my question title and text to be able as clear as possible. I have also added what you proposed in summary. Is there anything else I need to do to have my question reopened? $\endgroup$ – knowledgeseeker Jan 6 at 0:30

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