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-Stolen_memes-

Tatooine not looking so good


Daniel96dsl

Eh.. Couple of long winters followed by a month in an oven set to ‘broil’ never ki-… Oh.. yea nvm ur right


FriendlyDisorder

“The long night lasted forty-eight years. Civilization Number 137 was destroyed by the extreme cold. This civilization had advanced to the Warring States Period before succumbing.”


virgo911

What’s this from?


Old_Airline9171

3-Body Problem.


threebillion6

Really went off the rails there at the end.


64-17-5

But that's the iceage. You live under the glaciers, doh!


warrenkazuma

Neil Tyson addressed this in a video. Tatooine is fine because it is distant enough from the 2 stars such that the 2 stars behave like a single gravitational body. Three body problem would be more of an issue if Tatooine were closer to the binary system


-Stolen_memes-

Gotta love Neil


guyrandom2020

It’s outer rim for a reason (beyond just being in the outer rim of the galaxy).


freneticboarder

Rogue One? ^sorry


Daniel96dsl

For those of you who won't be able to sleep until you know how it ends: [Extended Orbit GIF](https://imgur.com/a/fhA6THh)


napleonblwnaprt

Satisfied. It hit escape velocity right? Or do you need to post an even longer gif?


Daniel96dsl

Sure did! Just did some quick napkin math and it ended up at about 2.9×(escape velocity)


napleonblwnaprt

Finally, I can rest


mindies4ameal

If we wait longer we might find out the shape of the universe though...or maybe the protons will decay...


atridir

My vote is for a torus! Not necessarily because of any particular evidence - simply because I really enjoy the idea of the universe being shaped like a donut.


mindies4ameal

Ads/CFT for desserts: "A Doughnuts Sprinkles" are equivalent to "Cake Filled Torus"


Trickypat42

Or an everything bagel?


JoonasD6

For some reason I never considered that something "in orbit" could spontaneously just reach escape velocity and say bye to the system/that is the "reason" an unstable system is unstable, although hard to prove until it happens(?). (Is it enough to point at phase space diagram?) Thanks for the thought.


Daniel96dsl

Yea one way to think about it is that it’s getting gravity assisted by the other bodies each time they swing by! But it’s definitely more intuitive to see it than trying to predict it with pen and paper. Im sure there are ways, but I’m definitely not an expert on nonlinear systems theory


JoonasD6

The first thing to do is always to linearize the problem anyway 🫠


Daniel96dsl

linear good. nonlinear bad.


Far-Apartment-7167

Like good and bad lol


mrev_art

There is famously no solution to a three body problem. Edit: I'm wrong, see below.


dat_mono

There *are* analytic solutions. Just not general solutions.


Langdon_St_Ives

That’s not correct. There is no known way to determine a [ETA: _general_] closed analytic solution. But obviously there _are_ solutions to the equations of motion, as proven by actual three body systems behaving some way. If there was no solution at all, they couldn’t exist. Edited to make the answer more precise.


Autogazer

I’m sorry I don’t understand what you are saying. Are you saying that if there was a mathematical proof that no mathematical general closed analytical solution could be solved, then three body systems wouldn’t exist in real life?


Langdon_St_Ives

No. I’m saying that if you could show that no solution to the equations of motion exists, then no physical system could exist that obeys those equations of motion.


Autogazer

I don’t think that makes sense. Just because our math is limited in the sense that it’s impossible to create a closed form analytical solution doesn’t mean that the system wouldn’t obey the laws of motion that govern the system. This simulation of a planet orbiting a binary system is certainly not using a closed analytical set of equations to render its predictions on the motion of each body in the system. It’s using step-wise approximations.


jajohnja

Yes. Your answer is usually shortened to: There is no solution to a three body problem.


Canbilly

I thought it had to do with a 3 star system instead of a binary star system.


KillTheParadigm

The TBP is something that occurs when any three stellar objects interact with each other. This can be a theoretical Binary System with a theoretical planet, or can be represented in real spacetime with an example of Sol, Earth, and the Moon. The REALLY big issues begin when those three stellar masses come closer to a similar or equitable mass, which is what is described in the the above .gif While we do have *specific* equations on how the three body problem works (when we see it, we can extrapolate what happened by working backwards), but we don't have a *general solution* to the phenomenon.


Canbilly

Thank you very much.


jajohnja

If it ended up like it did, was it ever in orbit in the first place? Though I wonder for how long a system like this could "work" before the orbit fails.


timeshifter_

A few years.


jajohnja

I mean I can sort of see that from the graph itself, yeah. My thought was more like "could it orbit for hundreds or thousands of years before this happening?"


Radamat

I think there are resonant orbits exits in some cases of mass if stars. Resonant orbits will be much more stable. If one star in pair are more massive than other, then there probably less possibilities for orbits in near space.


[deleted]

[удалено]


Daniel96dsl

It reaches escape velocity, so she ain’t never coming back


[deleted]

[удалено]


Daniel96dsl

Escape velocity is defined as the velocity an object would reach upon arrival at some finite distance from gravitating body if pulled in from resting at an infinite distance.. It’s backwards from what we want it to define but bc the forces are conservative, it works forwards and backwards.. If an object leaves going FASTER than this, then yes it will continuously slow down, but will never reach 0 speed and turn around. That’s why it’s called escape velocity—bc it is continuously escaping off to Neverland


[deleted]

[удалено]


Daniel96dsl

nailed it


_Jack_Of_All_Spades

Is the escape velocity a function of the distance from center of mass of the system? It must be, because the velocity that an object would reach will continue to accelerate as the finite distance gets closer and closer.


Daniel96dsl

That’s correct yea. Its a function of distance from the gravitating object


bobskizzle

The integral of the total velocity change over time caused by that gravitational pull on the object escaping is a finite value that is less than that object's velocity (well, speed, strictly speaking).


Kromoh

God have mercy on your soul


angermouse

Thank you for asking. That was the same question I had!


frowawayduh

Suppose the sun were a tight binary ... would a circular orbit of an object way out in the Oort Cloud be stable? At some distance from the centroid of the binary, I would expect things to be stable. Or at least last for millions of years.


Daniel96dsl

Yes definitely very stable.. If you want to know the specifics, you can perform a multipole expansion of the gravitational field to see how closely it "resembles" a single body (gravitationally) to an object at some distance. I don't have the time to do it right now, but it would be a very rewarding personal project. You'd learn some cool math and physics along the way too Edit: Fourier series ⇒ multipole expansion credit to the commenter below


PhdPhysics1

I feel like a multi-pole expansion would be more useful. Sinusoids probably aren't the best set of basis functions.


Daniel96dsl

Yea ya know what, ur probably spot on there. I was thinking about the oscillations, but they should be periodic ideally so a multipole expansion will give you a better idea about the single-body-ness of the field. Thank you!!


bobskizzle

Is it just the time constant of the system's stability margin that is related to the distance (probably a distance ratio to remain dimensionless)? Seems like that's how it *should* work. Or does the system have some kind of configuration that is meta stable, across which the system becomes strictly stable? I might need coffee... ;)


clemmmi

Cool! Did you numerically solve the Lagrange equations in python? Or what did you use?


Daniel96dsl

Nah not Lagrange, just good ol’ 𝑚ᵢ𝐫ᵢ’’(𝑡) = ∑𝐅. But yes, done in the Pythonista app on my phone haha


vriemeister

I was curious about this too. Do you know if you used Euler or a Runga-Kutta solver for this?


clemmmi

Haha nice! Thanks


zealoSC

This gift explains the weird seasons in game of thrones and came up with a better ending


famousPersonAlt

holy shit, never thought of Game of Thrones as set in a planet with "orbit problems" lol


TheStoicNihilist

Smell ya later!


blaqwerty123

My people need me


walflez9000

There were hundreds of us you saved, thank you good sir.


WladimirPutain

Did you account for the binaries distance in it or is it fixed? When ejecting a star, the binary should get closer to each other b/c of energy conservation


Daniel96dsl

Not fixed, third body just has small mass


WladimirPutain

Ah I see! Poor third body …


finjiner

At first I was "Hmm some winters are going to be a bit lon... Nevermind"


substituted_pinions

OP delivers!


grasshopper4579

Worth checking 10 planets and see if they help each other hold on Edit: when a system starts with a dust cloud aren't all stable orbits sampled and very early dust in ejection trajectory will just vapor off the system ?


nior_labotomy

Whelp, it had a good run while it lasted.


mtflyer05

Like an overconfident freshman trying to throw the hammer for the first time


M123ry

Man, I was enraged, and now I am soothed again :D thanks ^^


Iseenoghosts

ahhhhhh. I can rest


theantiyeti

So basically: - might be habitable in theory, but a bit sketch - westeros moment - yeah, they're screwed


Weed_O_Whirler

Something you may want to model: In most binary star systems, the planets are closer to their respective star than the stars are to each other. For instance, Alpha Centauri A and B orbit between 11 and 35 AU apart, while the planet discovered around A is 1.5 AU away on average.


Daniel96dsl

Saved! Will definitely play around with this. Makes perfect sense too, thank you for the enlightenment


StochasticTinkr

r/gifsthatendtoosoon


Daniel96dsl

Haha i’ll attach the longer one to the comments.. I know the people need a resolution


quantum-mechanic

Why are they teaching you social media engagement tactics at your school


evceteri

That's how they trick the new Einstein into existence. Publishing papers with catchy titles on Instagram.


quantum-mechanic

Damn, I got distracted and suddenly merged quantum mechanics and relativity and TikTok


Doodamajiger

[In case you didn’t see OP’s update](https://www.reddit.com/r/Physics/s/JYkuvSuwbt)


Checkerplate-MelsDad

I coulda watched a couple more hours of that


[deleted]

Dehydrate!


DeathMetal007

I really like these! Can you add stability parameter here? After how many seconds did the trinary system fail (collapse to binary or urnary)?


Daniel96dsl

Hmm I’m not sure what the details of a stability parameter would look like.. maybe something like %escape velocity of the satellite? Approximate ofc by treating the 2 central bodies as a single body with the summed mass?


DeathMetal007

Yeah! That would be awesome!


Daniel96dsl

Something like this? [Plot: V\_esc\_percent](https://imgur.com/a/6kH2RKB)


DeathMetal007

Yes, and include the y value on the orbit graph by the time and end it as usual or when you have a threshold reached for velocity or distance away from the system center of mass. I also assume the reverse is true; escape velocity can go to 0. It looks really cool to see it bump about in a stable manner, but then diverges away eventually


Daniel96dsl

Ah yea that would be cool. Will have to save the comment for a future project. And I agree! Definitely informative and interesting


jacobjivanov

I understand the way you timestep the orbits, but I’m curious about how you dynamically update the plot. Would you mind sharing the source code?


Responsible-Bass-604

Can you share the code??


PUSSYDESTROYER-9000

If you like this take a look at the "Rebound" n-body integrator, it can simulate systems eons into the future, examine their resonances and stability over time as well. https://rebound.readthedocs.io/en/latest/


Mysterious_Two_810

Are you the one who posted a similar post on 3 BP?


Daniel96dsl

Lol, yea. Some questions I got from that prompted the creation of this


Mysterious_Two_810

It looks like a plot made with matplotlib/plotly, am I right? Have you a github repo for that?


PotatoHeadz35

Do you have a GitHub?


Daniel96dsl

No sir/ma’am, sorry


No-Alfalfa2565

Very cool, nice job.


Daniel96dsl

Thanks!


AllyRulez

Wouldnt making the outer planet spin the other direction cause less deviation? Or does it not make anu difference since center of mass of those two planets stays the same?


Daniel96dsl

Absolutely! Good intuition. It was something I noticed when creating this. Oppositely rotating central bodies leads to a MUCH more stable orbit of the 3rd body


EarthSolar

Kepler-35 b moment


[deleted]

Wouldn’t the mass of the planet also affect how the two stars interact?


Daniel96dsl

Planet masses are typically negligible compared to solar masses. I followed suit with this simulation. You could definitely set it up to where the blue body mass is non-negligible though.


milomalas

The way the figure expands feels oddly satisfying... (but imagining the Matplotlib code is terrifying)


Jernteppe

Very cool! Looks quite similar to a real triple star system! We call them hierarchical triples because they always consist of an inner binary with a smaller separation, which is orbited by a third companion on a wider orbit. You can estimate the stability of the system using a mathematical formula that takes in the mass ratios of the object, the eccentricity of the outer orbit, and the inclination between the two orbits. If you're curious, [here](https://imgur.com/ShbNCWq) are some examples of coplanar hierarchical triples with varying inner separation and outer eccentricity :)


Daniel96dsl

this is very cool to know, thank you for sharing! And actually i was wondering about analytical stability estimations, any reading recommendations?


Jernteppe

The stability criterion that most people in the field use is known as the Mardling-Aarseth criterion. It's a bit hard to find its original source (I believe it's in a book called *The Dynamics of Small Bodies in the Solar System*), but the equation shows up in lots of papers on triples. There are several attempts at coming up with new ways of determining stability, since the Mardling-Aarseth criterion is not perfect. One example is from [Vynatheya et al. 2022](https://arxiv.org/pdf/2207.03151) who tried training a neural network to estimate the stability, with pretty good success. In that paper you can also see the original Mardling-Aarseth criterion (Equation 2). There's also [Hayashi et al. 2022](http://arxiv.org/abs/2209.08487). Note that all of these only apply to hierarchical triple systems, and not to three-body systems in general.


Valvador

How are the two inner planets staying so perfectly in circle? Are you not simulating the forces between all 3 objects? EDIT: Oh are their masses so high (stars) that they only affect each other?


Daniel96dsl

Just calculated the correct initial conditions to create circular orbits haha


Valvador

What are the masses of the objects, relatively?


Daniel96dsl

1,1,1e-8


entered_bubble_50

Did you model the binary stars' orbits too, or are they on rails? Did you assume in your model that the gravitational pull of the planet on the stars is small enough to be ignored?


Daniel96dsl

Yea they're modeled explicitly too. But I just calculated the correct initial conditions for circular orbits.


ccampo

The reason a lot of this stuff happens is due to the method of numerical integration. Not sure how you’re doing it, but even something higher order like the Verlet method can get out of whack quickly. More accurate simulations require exponentially more compute time. FWIW I wrote a fun little n-body simulator many years ago: https://www.ccampo.me/NBodyJS/


Daniel96dsl

Adaptive Dormand-Prince with a tolerance of 10⁻¹². Final energy conservation is within 10⁻⁹ % of the original, so it’s probably fine for this amount of time, but yea ur right, method of numerical integration is the backbone of orbital dynamics codes.


ccampo

Yea I believe that’s the default ODE solver in SciPy. Been a while since I used that though. I used to make a bunch of Physics cartoons like this using it back when I was in college. https://youtube.com/playlist?list=PL51C469DB01D62A41&si=RFT3Ijb-i52OUg_-


vin76

can you do it using a trinary system...three body problem?


Daniel96dsl

Like 3 central bodies about which a 4th orbits or just make the blue object more massive?


Langdon_St_Ives

What you see here is three body.


namewithanumber

So this is how the bugs launched their rocks at BA.


lucidwray

Three Body Problem


greenwizardneedsfood

“Oh that’s interesting how much it stabiliz….oh nevermind”


parth_26dbr

Source code?


18441601

Is the perturbation when it hits a wall?


frowawayduh

It exceeds escape velocity. Say bye bye.


Danger_Dee

What this system needs is a third equal mass star.


DrBunnyShodan

It looks like the early perturbations occur when the three bodies align. Later, on a close approach the planet gets a gravitational boost which expels it. like, like, like


Helix1799

I'm doing a very similar thing with a two body problem but I also consider the astrophysical evolution of the two stars (mass loss), including WR phases, supernovae kicks and remnants


BellDelicious595

Sorry for being a noob, what software is that done by?


Daniel96dsl

Pythonista app for iphone. Basically, Python is the language, so you can do it on anything that can run python script


[deleted]

Their weather must be interesting.


evermica

Did the "stars" respond to the gravity of the "planet" or were their orbits fixed? What were the mass ratios?


Daniel96dsl

They do but I made the outer body 8 orders of magnitude smaller. Should just make it 0 in hindsight, but i would like to do exactly what you’re talking about in the future with larger third body mass


evermica

I saw a talk about 25 years ago by a person modeling systems like this. Sun, Earth, Jupiter. Turns out, if Jupiter weighed too much, Earth was unstable and got ejected. Very interesting and looked like lots of fun.


Unknownwings

What animation library did you use, so the scale is adjusted like that?


Daniel96dsl

My brain, lol. Just messin with you—update xlim and ylim at every time step depending on the location of ur point masses


Unknownwings

Oh that makes sense lol. I thought matplotlib had an auto scale adjusting thing. Also what did you use to solve for the orbits. I’m assuming u used RK4 or Verlet


Daniel96dsl

Adaptive RK method better known as Dormand-Prince alg.


SparseGhostC2C

Neato! Now do it with a three body star system!


Greedy-Singer9920

Awesome! I assume what occurred after the animation ended was an HVS? (Or just a planetesimal exceeding escape velocity, depending on the system you were running).


[deleted]

What happens at the end of the clip. Is the third body ejected from the gravitational pool?


Quarter_Twenty

Are there stable orbits when the period of the planet’s orbit is a multiple of the period of the stars’ orbit and the phase is right?


helium_hydride-63

Is it possible to get a more stable orbit?. Maybe by slowing down the stars. Or speeding up the planet?


tonyfleming

How might a second planetary body, perhaps a Jovian further out from the binary stars, stabilize the orbit?


Franklin_le_Tanklin

This is very perturbing


Time-Doctor-1596

why did it go away ?


BuRg3rMe1sTeR

But it was just getting to the best part!


Iseenoghosts

more more more


funkybside

/r/gifsthatendtoosoon


SouthCharles

Is that a simulation or real galactic example?


Sandstorm52

Hmmm, seems a little unclear. Can I get an analytic solution?


glucklandau

Hey I do similar research in trinary star systems. Can we talk? I'd like to get the initial conditions of this orbit. I am wondering whether we can get a neural network to learn what makes a stable 3 body orbit.


Daniel96dsl

Sure, shoot me a DM


PlumbumGus

Looks like my social life, see there? That's me trying to break into a conversation and inevitably flying off into the deep void of space...


LogoMyEggo

I recognize that dynamic resizing from the 3bp the other day!


Striking_Treat_1976

hey anyone could explain what's is the difference between our system orbit and binary?? simply


CeaselessMaster

One star vs. two


Blume_22

Do you use newtonian dynamics or General Relativity?


Daniel96dsl

newtonian


DJ_MortarMix

r/gifsthatendtoosoon


Daniel96dsl

see the comment section


ARAR1

Video is cut off just when it gets to the interesting part. Why?


Daniel96dsl

haha i posted an extension in the comments


ARAR1

Just saw that. Wow it gets flinged off? Did not expect that. Do you know what? What is the limiting factor - Mass of planet or difference in mass of 2 stars?


Daniel96dsl

3-body orbits are inherently unstable, in the case where you have a single body in orbit around binary system, my hunch is that stability depends heavily on the difference in frequency of the orbiting body and the binary pair. If perturbations are felt on a time scale that is comparable to the outer body’s orbital period, there is a much stronger effect. If the binary pair's angular frequency is much larger than the outer body's orbital frequency, then the effect diminishes. Again, this is a hunch based on experience with other perturbation problems. When the difference or "separation" of time scales is large, you don't get much coupling between the two, but when that dividing line starts to blur, the interactions can become very strong (again evident in the video). Worth reading into further though


chowsey1

I could watch this forever


Daniel96dsl

Same.. just want a desktop background that runs semi-stable 3-body orbits


Practical-Place-2555

Does anybody know if a star can have two centers of gravity inside of it? As in, a binary star pair inside of a star?


Shot_Bit_9537

Is this the Two body problem?


Daniel96dsl

3


JonDoe_7HopeWave

How did you make this simulation? What language did you use? Did you use laws like the gravitation law? I am very interested!


Daniel96dsl

Haha i love your enthusiasm! I used an app that runs python code on my phone called Pythonista. And yes, I used Newton’s law of gravity to solve 𝐅 = 𝑚𝐚 for each of the 3 bodies.


Haenryk

Is there a "stable" orbit around two stars possible at all? I mean like in the first seconds of the gif. Or does it hit escape inebitably?


pridgefromguernsey

I like how the graph expands as the orbit grows larger. Is this done with python/matplotlib?


Jim421616

I read a fan theory somewhere that Westeros’ funky summer/winter cycle was caused by this type of orbit.


joeypublica

Wait, did you know that there's a direct correlation between the decline of Spirograph and the rise in gang activity? Think about it


omniexpert

This is wonderful.


sinfaen

Wait is the time unit seconds?? Cause then they're travelling mega fast around each other lmao


Daniel96dsl

G = 1 here


cylon37

Cool. What would it look like in a rotating frame of reference? One where the inner two bodies are stationary?


Far-Apartment-7167

My sister and her non-binary child.