Hot Jupiters are not rare, but there is no other one that orbits its sun in less than one Earth day. How do the tidal forces even allow such a situation?
A planet the size of 10 Jupiter masses has been discovered that revolves around its parent star in less than a day (Yammat KDA).
The discovery, published in the journal Nature by Koel Helier and colleagues from Keele University in the UK, poses a challenge to our understanding of tidal forces in planetary systems.
The planet WASP-18b belongs to the category of planets outside the solar system called "hot Jupiters" - massive planets that probably formed far from their mother star, and migrated over time to their current location. WASP-18b is so large, and so close to its parent star, that the tidal forces between the star and the planet should cause the planet to spin forward and cause its destruction in less than a thousandth of the parent star's lifetime.
However, as Leyer and his colleagues show, WASP-18b's parent star is about a billion years old. If so, either WASP-18b is in a rare state of extremely short life span, or the tidal forces in the entire system (and possibly other hot Jupiter-type systems as well) are much weaker than in the Solar System.
53 תגובות
Yael: Thank you.
Michael: I didn't have a conversation, I just asked. And I explained to the point that he simply did not understand my question. And besides, I already mentioned that you answered me.
Isaac:
Although your response is annoying, it only betrays your lack of understanding.
Yes. Wikipedia also says otherwise.
Actually in every text that discusses the theory of relativity it is written differently.
Newton's equations are still a good approximation, but precisely their deviation from the findings on the orbit of the planet Mercury was one of the decisive proofs of the superiority of general relativity over Newton's theory of gravity.
Besides - even if your words were true - they don't take your words into account.
I just pointed out the fact that the questions of a white blood were actually about general relativity and not about Newton's theory, and this had nothing to do with the results of the calculations.
Continue to stew in your hatred
Michael, when it comes to planets, classical mechanics and with it Newton's equations are all still correct. Or maybe Wikipedia says otherwise?
Yael:
I don't know who you tried to answer, but if it is a conversation between a white blood and a dot, then the discussion between them does not concern Newton's mechanics but general relativity.
White blood - as I said - it's a shame that you have conversations about the subject before you learn a little more about it.
When a planet revolves around a star, it means that there is a (simulated) centrifugal force that pulls the planet out, and it is perpendicular to the centripetal force that pulls it in, and since the forces are perpendicular, the size of the centrifugal force does not change, thus maintaining the balance that causes the planet to rotate in a certain radius.
point:
You did not understand;
I didn't ask how the curvature causes gravity or the spiral rotation, I asked if this is really the reason, so how come it doesn't continue the rotation until it "crashes" into the star, but stops the attraction process suddenly and then just continues to rotate in the same fixed orbit.
But Michael already answered me
Higgs:
Instead of regretting, it is better that you litigate with due seriousness.
I don't understand why we both understand, rather I have to insist that your words be comprehensible.
If you don't want them to understand - why did you write them?!
It's not like you didn't say anything.
One of your responses, which seemed very confusing to me at first reading, implies a correct idea (in general) but does not explain its connection to the current situation.
I will allow myself to present the idea that is hidden in your response 37 in a way that will also allow others to understand it and point out what bothers me about its association with the current case.
An important element of this idea is the following fact:
Equilibrium situations in nature can be divided into two types.
Stable equilibrium and unstable equilibrium.
Obviously, the chance that we will naturally encounter an unstable equilibrium is zero, and therefore it is quite safe to base ourselves on the assumption that if we encountered any equilibrium, then it is a stable equilibrium.
What makes such a stable equilibrium?
This is done by something in the dynamics of the system that tends to "correct" small errors (ie - if we deviated slightly from the equilibrium due to one reason or another - there is something in the system that will pull us towards the equilibrium).
This is what causes the ball at the bottom of the bowl to be in stable equilibrium.
As long as he doesn't catch a bomb that will throw him out of the bowl, he will stay at the bottom of it even if he takes small hits from time to time.
A synchronization equilibrium between two systems is such.
For example - the moon is completely synchronized with the earth in the same type of synchronization that you are talking about, only in the more impressive ratio of 1:1 (not in the ratio that there is room for thinking that it might be a point of 2:3) and we really know that this situation was created due to the "correction" ability of the system: the same system of forces that brought about the synchronization (tidal forces) also maintains it and any small deviation is corrected by negative feedback.
Therefore, dynamic systems, part of whose dynamics is based on stable synchronization, can, sometimes, overcome small problems and preserve the dynamics despite the disturbances.
For example - even if we put a one-way race track on the moon and run a racing car on it in a fixed direction without stopping - the moon will still "succeed" in maintaining the state where its fixed side is facing us.
So far so good, so it makes sense to claim that synchronization modes between systems - even those with less impressive synchronization, tend towards stability.
So what's my problem?
As I mentioned - it consists of several sub-problems, none of which you gave an answer to.
One is that, contrary to what you say - the existence of additional bodies is of crucial importance in maintaining the stability of suborbital-orbital synchronization in a value different from 1:1 and in our case no such bodies were discovered.
The second is a matter of magnitude and context. For example - if we place a small clock on a huge and unstable system, then the existence of synchronization in the clock will not stabilize the system (this is the matter of order of magnitude). Even if we put a huge clock on it, it won't have an effect in many cases. For example - a mechanical watch, no matter how big it is, will not curb electronic instability (that's the point of the context)
The third is that we have counterexamples to the ability of sub-track synchronization to maintain a constant distance, so even though in the song "only the moon shines", in reality it is not only the moon that escapes.
The fourth (I remembered it now although I should have mentioned it as a second section) is that the existence of suborbital synchronization requires a stable non-uniformity in the internal structure - something that is very unlikely in a star orbiting the Sun at such great proximity.
As long as you do not answer all these problems, it will not be possible to see your words as an explanation.
Michael
sorry too bad
Higgs:
I was desperate.
White blood, a simple explanation for your question about how the spatial distortion causes bodies to rotate.
Just take a gulahao each small ball and send it to the sink, pay attention to the path the ball takes...
Michael
Today it is known that chaotic systems can be brought into resonant states quite easily. Several such states can live simultaneously in one chaotic system. There are materials about it on the internet I think. Although it is possible that these things are a bit complex. All in all, I tried to enrich the base with additional things. What is interesting is why here you insist on seeing complete proofs, while in topics such as the monkey experiment there is no need to observe mitzvot compared to humans. You do not require it.
Higgs:
What do you mean by "no point"?
Do you want them to believe you just like that without substantiating things?
As you have seen, it is possible to describe such things (when they are correct) even without mathematics.
I did not understand what Wikipedia has to do with the matter.
Michael
These are areas that I deal with in my work and there is no point in writing the math here.
There is much more to Nonlinear Dynamic Systems than Wikipedia.
Higgs:
You didn't say anything except to say that it is well established.
To see what I mean by the word "foundation" (it really surprises me that this is necessary) I suggest you read my responses 5, 6, 8 and 9.
Hand waving is not grounding.
Michael
It is fully established and found in many dynamic processes with non-linear characteristics. When noise is introduced into them and cyclical movements of different types are added to the same system. See for example the wiki. About Stochastic resonance. And that's just the tip of the iceberg. Such a method is used, for example, to amplify lasers or to characterize their frequency dynamically, etc.
Higgs:
You gave no explanation.
Is there a possibility that something?
Maybe. You have not shown this and no article you have provided claims this.
Your last comment somewhat reminds me of the Sokel case:
http://en.wikipedia.org/wiki/Sokal_affair
Michael
Only part of the disturbances is due to other stars, the rest is due to a more repeated curvature of space according to general relativity in the Sun's environment. The deviation of the perihelion is affected by this. This also manifests part of the resonance.
I refer to resonance as the ability of a system to absorb and integrate into it any external or internal disturbances.
in a way that enriches the fluctuations of the general dynamics of the system. That is, there are potential elements within the system that are reflected in additional movement of various types following the contribution of the disturbances.
In resonance the dynamics become richer. Then there are two options or it will contribute to the stabilization of the system. Like adding more instruments to an orchestra. Or the system will exceed a certain saturation limit and then lose stability and fade away.
cute 🙂
Oh sorry… 🙂
white blood:
Have you decided to call me Yael?
Thanks Yael, I will read
But hey, that's what I'm here for, right? – to be educated 🙂
Higgs:
I see you didn't read Wikipedia as I suggested.
Read the last paragraph in the Spin-Orbit Resonance chapter of the Mercury article.
It is written there that the special resonance of 2:3 is obtained as a result of the fact that, thanks to the involvement of other stars, the planet's orbit becomes very elliptical in certain periods and that otherwise it would have reached Tidal Locking, i.e. a ratio of 1:1 as satellites usually reach.
In any case - in none of the links you provided does it say that this fact contributes to the stability of the track.
The only thing required to explain its stability is this ratio of 2:3 which in any normal situation would fade to 1:1 (and as mentioned does not do so because of the involvement of other stars).
Michael
The involvement of other stars in the resonance of Hema is negligible. Although it is the giver, that is, there is a tendency to create resonance in star systems precisely as a result of the addition of permanent disturbances to an orbit that has a tendency to be non-linear.
Below is a nice link with a drawing depicting the orbital resonance of the planet Hema.
The nomenclature in the English source "Mercury's Orbital Resonance" uses the word orbital.
http://www.windows.ucar.edu/tour/link=/mercury/News_and_Discovery/Merc_orbit_reson.html
Michael
Ok, I'll give you up on the word "orbital", my main intention was the existence of a resonance that maintains stability over time precisely due to the constant contributions of the disturbances as a result of the high strength of the field.
As we know, the curvature of the orbit of the planet Hema is completely consistent with general relativity precisely because the relatively high strength of the curvature of space is reflected here.
These disturbances in the example of the above article may contribute to the state of resonance and stability of the system despite the rapid rotation of that very large Jupiter.
By the way, if you read on Wikipedia about the planet Mercury, you will see that this resonance of two thirds was created in it due to the involvement of other planets.
Nothing is written here about the stabilization of the route either
I'm sorry, Higgs, but here we are not talking about an orbital resonance, but a resonance between the self-rotation and the time of revolution, which is precisely the carrier of the tidal forces that I spoke about in the first explanation.
Michael please
This is the planet Hema which is in a stable orbital resonance with the Sun when the disturbances of the gravitational force cause the stabilization of the resonance. In the article below, for example, the sums of states were calculated using the Hamiltonian method below.
http://www.springerlink.com/content/g36k7046q0688715/
Higgs:
I wrote my previous comment before I saw your last comment.
I still stick to it. I only brought Wiki as an example, but you know what? You are welcome to bring one source that talks about the same type of "orbital resonance" you are talking about.
Alternatively - you are welcome to explain the physics of the orbital resonance mechanism you are talking about.
Higgs:
What happened to you?
When one orbits the other it is exactly the same as both orbiting a common center of gravity only viewed from a different coordinate system.
In any case - in all these situations - the cycle time of the two bodies is the same.
It just doesn't belong in orbital resonance.
Maybe you can tell me why all the charts on Wikipedia include more bodies? After all, the fewer bodies there are in the diagram, the simpler the explanation should be.
The reason is of course that orbital resonance does not exist when there are only two bodies nor when there is only one body. So the simplest example involves two planets around one parent star.
It's also starting to get funny because you just used the word and didn't give an explanation.
Even if I gave you up on the wrong use of the word - I would not be able to get any explanation from you.
Michael
The key sentence in the quote as a major cause of resonance is:
exert a regular, periodic gravitational influence on each other
There are other sources for the matter other than wiki, check.
Michael
Clean resonance occurs between a pair of bodies and it is not necessary that they both orbit a different center of gravity. But even if both surround each other and also if one surrounds the other. Precisely when they are very close and close in mass, a resonance will be created.
Higgs:
It was I who said.
In order for an orbital resonance to occur, two bodies are needed to orbit the sun, not one.
If you look at the diagrams on the wiki - you will see that this is what it is about, but it can also be understood from the wording of your quote.
How can different cycle times be possible when it comes to two bodies revolving around a common center of gravity?
Of course, the cycle times of both are the same, so it is clear that this is not the case.
Michael
Quoted from Wiki
In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other, usually due to their orbital periods being related by a ratio of two small integers.
Michael Rothschild
Orbital resonance between two bodies is very common and precisely when there is a strong gravity that contributes to permanent corrections in the orbit. Check please.
Haim:
Higgs is right and wrong.
He is right that these are different phenomena.
He is wrong in that his explanation is relevant.
Orbital resonance is a phenomenon that exists between two bodies revolving around a third body (for example - two moons of Jupiter or two planets) and has nothing to do with the described situation.
It is also unlikely that there is another significant body in the system because they would also have discovered him on the same occasion.
Life
You protect Michael's honor well and he definitely deserves it for me as well
But orbital resonance is another matter.
Invites you to browse Wikipedia as usual.
Higgs boson! There is no need to repeat in Chinese what Michael explained so well in Hebrew
Error correction and clarification
1. Michal Chal Michael. Forgiveness is with you.
2. "Simple" - means explanation. The process is complicated.
To a container
Thank you for the excellent explanation. Simple and clear.
It is possible that the two bodies are in stable orbital resonance. The size and short distance contribute to an extremely strong gravitational field. And it is possible that this is what contributes to suitable offsets in the track and its stability.
Mickey:
I did not understand what you were saying.
You should also notice that systems in nature are not created under any assumption. They are created because of the laws of nature.
Raphael:
Please tell me if you understand.
??
According to what it sounds like, these are weaker forces, because the entire system was created under the assumption that the centers of mass at the time of the system's formation were in such a special state...
Just another little note:
A tide does not require water or any liquid.
The land also "rises" (less than the water, but still something).
Every body has a certain elasticity that allows it to "rise".
In fact, it is not real elasticity and the body suffers as a result of the movement of the tides from internal friction that causes it to heat up (and of course, later on, to emit the generated heat).
Raphael:
Here are all the details:
http://en.wikipedia.org/wiki/Tidal_acceleration
I am afraid, however, that precisely because of too many details you may have difficulty seeing the forest, so I will add a few words that make it possible to understand the matter "in the big picture".
The moon causes tides on the earth.
I won't explain the whole process right now (I explained it in other comments before and it's not really important for this explanation) but the tide moves on the surface of the earth and at each stage it settles so that the height peaks of the water are at the point closest to the moon and at the farthest point from it.
Since the Moon orbits the Earth further away from the geosynchronous orbit, it rotates around us at a smaller angular speed than the rotation of the Earth on its axis.
Therefore the tide created by the moon at a certain moment is pushed by the rotation of the earth and tends to "catch up" with the moon due to this push.
This means that the moon has to "drag" her back to align with him.
That is - the moon "drags" the tide in a direction that is opposite to the direction of the earth's rotation and to the direction of the moon's rotation around the earth.
Since every action has a reaction (as we hope Hamas and Hezbollah have already learned), the tide pulls the moon in the opposite direction to the direction it pulls it - that is - it accelerates its motion in orbit.
As we know - faster movement in orbit - "throws" the moon into a more distant orbit.
If the moon were closer to the earth than the geosynchronous orbit, it would "catch up" with the tide and therefore it would pull it "back", that is, slow it down and cause it to approach the earth.
I hope the explanation is clear now.
If not - I'm here.
"This is why the moon is gradually moving away from us"
Can I get more details?
Some emphasis:
If the parent star rotates very quickly then the planet may even spin away from it and not align
Yael:
"swirl in" and not "swirl forward"
white blood:
You usually express yourself intelligently but your questions about gravitation are really confusing and indicate that you have never read anything about general relativity.
Please: read a little about the matter http://en.wikipedia.org/wiki/General_relativity
Yigal C and Blood White:
A star that revolves around the sun usually formed together with you and did not come to it from a distance.
A star that comes from afar - returns and moves away from the sun and even if it is captured by its gravity - its orbit is very elliptical and its orbit takes a long time.
Everyone:
If you look at the planet as a point body moving in space without energy loss then there is actually no reason for it to fall in the direction of the sun. In such a situation he would continue circling her forever on the same course he was in from the beginning.
What changes the situation is the tidal forces.
Each star has a radius at which the stars that move are "stationary" or "synchronous" in relation to it - that is - they are always at the same point in the sky (the orbit corresponding to this radius in relation to the Earth is populated by the geostationary satellites).
The relevant radius is a function of the star's mass and its rotation speed.
A planet that rotates below this orbit gradually falls (in a spiral orbit) towards the mother star and a more distant planet - gradually moves away.
A planet that is right there…. stayed there
This is why the moon is gradually moving away from us.
It could also provide some explanation for the planet staying in orbit longer: perhaps the sun it orbits rotates exactly as fast as it orbits it and then tidal forces have no effect on its orbit.
I have ignored here the energy loss that is assumed to be caused by the gravitational waves created in the process because they are supposed to be quite weak in this case.
Look.. what Einstein claimed is a different thing. He claimed that it is not that the bodies attract each other, but that each of them affects the space-time in a way that distorts it. We see and feel this curvature as gravitation.
Imagine a stretched sheet, on which a basketball is placed. The sheet is space-time space. Basketball will be in the role of the sun.
The ball creates a dent (=curvature) in the sheet. Now, suppose a sphere (represent the Earth) is some distance from the sphere. What will happen is that the gula will "sail" on the sheet along the curve. What's more, the marble creates curvature on the sheet, which affects the ball somewhat (but not too much). But if we were to put handball (a bigger star) then we would certainly see the effect on basketball (the sun).
This is briefly what Einstein claimed. Now just try to imagine the sheet surrounding you from all sides and in every direction. And the ball twists the sheet in every direction at the same time.
I hope I shed some light (what do you think, Yael?)
white blood,
The movement of the type you describe (the approach of two large bodies moving towards each other) is never a spiral and not in a straight line, and this is because each of them begins its movement when it already has some velocity that is in a different direction from the line connecting the two bodies. Combining this speed with the acceleration caused by the pull of the two bodies creates an accelerated helical motion and it is possible that what is observed here is the last stages of such a motion before impact. My guess is that it is an extremely small ("sun") star, so the system is more like a double star than a star
for a planet-planet system.
This brings me back to my question in the previous article:
If it is the curvature of space that creates gravity, and in addition the planet Hagar moves from a distant place - to the vicinity of the sun [due to gravity, I assume(?)] then how is it that it does not continue to move in the same direction and crash into the sun?
I think this is indeed the rare case of watching a planet on the verge of collapsing with its parent star.
It is necessary that out of all observed cases, we occasionally observe rare cases.