Slormp, if you're reading this you should probably make a pinned comment issuing a correction that Lagrange points are NOT where the gravity of two orbital bodies cancel out. Rather, it is where the sum of the vectors of the planets gravity exactly equal the centrifugal force needed to maintain an orbit around the larger orbital body. Other than that, nice video.

mad respect for labeling the "Red Clickbait Arrow" on the thumbnail

watching him do a sun station landing attempt was amazing, lets be honest, we all tried it atleast 20 times

Cool space fact: the binary star system T Coronae Borealis is not only an example of this type of system, but it also is a recurrent nova! When the smaller dwarf absorbs enough material, it explodes all the excess into space with a very bright explosion. It's actually expected to happen again some time in the next few months, and for a few days it will be naked eye visible at night!

Hi! Since you talked about the gravity of the Hourglass Twins, have you ever noticed that it changes depending on the amount of sand on each planet? Since the Ash Twin is basically hollowed out, it goes from 0.8 to like a 0.4. Conversely, I'm pretty sure the extra mass from the sand makes the Ember Twin's gravity go above 1g. The physics of Outer Wilds are really cool.

my own headcanon for why the sand alternates between the two planets was always that it had to do with the gravity of the sun, which is so close by. basically, the gravitational force of the other twin isn't normally enough to pull the sand by itself. but when the planets rotate around each other until they're lined up with the sun, the gravity from both the sun and the other twin are acting in the same direction, and it's just barely enough to pull the sand off the planet. of course if this was actually the explanation, you'd probably expect the sand to kind of smoothly rise like a tide, rather than just switching on like a faucet, but hey this is a solar system where a planet can have a black hole at its center, so who are we to judge!

i wish more writers created this type of planetary duo for their fictional star systems i absolutely adore the idea of two planets that occasionally throw a vast amount of material from one to the other, can even get cool worldbuilding by just having it as decoration in a world's night sky but aside from things of my own creation i can literally think of 2 examples and i don't even know the second one's specifics the hourglass twins throwing their sand and a set that threw an ocean around from a disney cartoon i remember was on the tv for a little kid when i was visiting some family ages ago

Complex orbital mechanics and Outer Wilds, my two favorite things combined into one video! Incredibly cool vid!

Something that you didn’t consider: the sand exchange starts when the planet with all the sand is at its furthest part of its local orbit from the sun (and accordingly the planet without the sand is at its nearest point) so perhaps the sun initializes the transfer at which point the sand accumulating on the receiving planet pushes the L1 point away creating a siphon like effect

Dude! This is actually awesome! Complete hidden gem.

The main thing with these is that in reality you need extremely dense cores with an ephemeral mantle to support this situation for long periods. Pretty much all contact binary planets I've tried to create in simulations with realistic materials and size between that of the moon and Neptune collapse within hours.

The cutaway upon contacting the sun station followed by a cut back to vaporizing in the sun will never get old

Super cool video! I knew about mass transfer between stars but didn't realize that mass could be transferred back and forth in a cycle as the roche lobe changes size, so that was really interesting to learn

My personal theory is that the sand flow isn't caused by gravity, but by weather. Its basically a dust devil that happens to throw sand higher than their shared center of mass. Maybe there's just a solar flare that hits the (thin and unbreathable) atmosphere just the right way to get things spinning every once in a while. Who knows if it would actually be realistic, but at least it has a power source (the sun) so it's thermodynamically possible, and atmospheric dynamics are complicated enough that i can fool myself into thinking theres a way.

Actually, one of nomai writings in game points out that teleporters point not to the center of objects, but center of their mass, with inclination of 5 degrees. Thats why ATP teleporter turns on when pointed at ember twin.

More people need to watch this, very good

Subscribed. Your content is genuinely entertaining. It has a very classic jan misali/Vsauce type of vibe, and with the frequency you create these, I hope to see much more to come and look forward to watching you grow. :)

This is great, can tell you put a ton of effort in

Came for the red clickbait arrow, stayed for the planetary mechanics. A+

Great video and answers one of the questions I was thinking about when I played Outer Wilds. I've noticed that you have a pretty diverse content on your channel and so I don't know if there will be more content on Outer Wilds that I'm interested in. But if you do continue, I'll offer some ideas that could also be considered from a scientific perspective (contains spoilers): 1. Flying out into space and coming back in from Giant's Deep islands. Perhaps something similar exists with water geysers on icy planets (Titan, Enceladus, and Triton). 2. A planet that is constantly bombarded by its satellite, like Hollow's Lantern constantly bombarding Brittle Hollow. 3. The rupture of the core of the comet Interloper. We can understand that the core was blown apart by internal pressure and the matter moved (almost) instantaneously throughout the solar system. It's unlikely that it would work that way in reality, but what if it did?

such a good and interesting video! i'd wondered this myself a few times. very fascinating to hear all the explanations :)

*dope* vid, can tell you were up researching long past the need for sleep. thanks for teaching me about binary orbital mechanics!

I really like this video. I forgot how much I like nerdy gaming stuff. You deserve way more views and attention.

fun fact: the sand actually switches between the 2 twins in a cycle

Subscribing just because you actually put in the effort to subtitle your vid

Here are some ingredients to something more plausable: - Stars and planets have magnetic fields, that could alternate from time to time. - Iron can become a big magnet itself, when it is in a magnetic field. - Ironoxide can still hold magnetic properties. Even when mixed with Siliciumoxide. - Magnetism can reach far when connected. And thus can be stronger than gravity. So, this is what happens, the star switches its poles. The planets are somehow affected in the field as well. The sand is now attracted to the other planet. Since the magnetic pull is stronger than the gravity. Once a connection has been made, it goes very rapidly. Once the star switches poles again. The proces reverts.

thanks for pointing out the clickbait arrow i almost didnt see it

Now this is peak

Remember that inertia is a thing, so sand could move to the Lagrange point in the middle of the planet but inertia would keep it moving towards the red planet. And this is a chain reaction, because the more sand that moves towards the Lagrange point, the closer this point gets to the red planet eventually putting this point inside the planet and this sucking all the sand

ah so this was why one of your videos was recommended to me. it was because you just made this outer wilds video.

0:23 Ah i love the teem non-zero. It's always used for numbers like 0.0000000…1 so incredibly small that to humans it's basically zero.

The twins do not actually have roughly the same gravity. You can actually see the gravity counter decrease on the ash twin and increase on the ember twin over the course of the loop Great video tho

Bro’s asking the real questions.

Subbed around 6.16k Im investing in this channel before it gets famous

Man this game's soundtrack is absolutely perfect.

Pretty cool!

Hi, the backing music to this is nice, do you have a tracklistm (or just a general idea of what was used, or was it all just random royalty free music)

Something like the hourglass binary planets is super rare because the pillar itself would consume a huge amount of the orbital energy from friction, it would not be something you could see for very long unless the planets involved were basically made of diamond and only a superficial amount of material forming the bridge existed.

the first thing i thought of when seeing this was the roche limit and how one planet ripping another apart may resemble the hourglass twins, but that would be a 1 way transfer of mass

This is very cool

This is a very interesting physics problem, are you okay if I use your video as a source for an essay im writing on Astrophysics? @Slormp

One thing to note about this game is that all gravity, except the suns, is linear, unlike our more exponentially decaying gravity. This is so the planets can be so close without trying to murder each other.

ive never played outer wilds before but this is kool.

In game lore says the sand swaps planets, so if the cycle lasted longer. We could see sand go the otherway

I didn't finish it, but Robert L. Forward wrote a novel about a similar double planet called "Rocheworld."

I heard that outer wilds doesn’t have the planets just move around a set path but that they are on an actual orbit, they move on physics moving them, they are actually orbiting the star.

So, while it doesn't function like the hourglass twins, I think you should take a look at Arrokoth. Its a Kyper Belt object that is comprised of two objects that have come close enough to touch. And while there isn't anything flowing between the two objects, there seems to be a tendency for some materials to gather where the two lobes touch. Might be a fun read.

Thought of a possible solution while watching. They are the innermost planets of their system, and considering how even as far out as we are, the sun still has an influence on our tides, perhaps it could be reasonable for them to exchange matter, going from the planet furthest from the star at any moment in time to the one closest to the star at that moment in time, having the star's gravity assist with the mass transfer.

Hey can you provide the references for this video. I mean the formulae for Roche limit and roche spheres

Without watching the video I instantly thought of Pluto and its moon-satellite that gets frozen stuck to Pluto during methane spews sometimes. very neat stuff.

7:14 that gravity indicator isnt the most reliable thing, though i suppose its a matter of perspective, it updates in real time, im pretty sure as the sand goes down you can see the gravity go down and if the ember twin is directly underneath you it will display higher because embers gravity is helping to pull you down. Im not completely sure about that last one, needs testing.

7:24 interesting. so on Giant's Deep where the gravity intensity mattered mechanically, did you just go by feel?

Cool video man, I hope you get more exposure

I allways liked that idea of merged 2 planets. Its one of most unique and interresting imagined obcject that im preety sure was never made into sf, and if thats true then i think its missed opportunity for great worldbuilding.

Anyone else JUST NOW learning that Pluto has a twin that is NEVER talked about?

There's a classic sci-fi book about something like this. It's called Rocheworld

pluto is an honorary planet in my books.

Ah yes outer wilds, the game that impresses me so much and is my absolute favourite game of all time that also gives me deep feelings of existentialism and a constant reminder of the size and scale of the universe and it's horrifying void I remember after i beat the game i tried it out with the VR mod and holy shit.. it's terrifying

Tldr: you can stand next to the sand column in outerwilds nothing happens. You can even throw yourself off the ground in lockstep with the sand column and you'll end up thrown off course and not hit ember twin. Even if you got into the sand column if you turned off the friction the sand applies you would slip out of the path to ember twin. The physics just don't physic. A couple really big issues with this concepts: all the stuff that you talked about was for atmospheres. Gases have varrying internal speed (following the gauss distribution there are a lot at moderate speeds and smaller amount of particles as you go beyond the average-ish speed). If you put sand beyond the roche lobe of a planet... it wouldn't go anywhere because the gravity isn't strong enough to rip it off the surface only to provide the extra delta V the particle needs to reach the other body during the flight. That brings us to the second issue. If a planet was within the actual roche limit (the thing you would need to pull sand up) it would also rip off the entire atmosphere, oceans, and continents because the tidal forces are stronger than the planet's gravitational pull. Planets don't resist tidal pulls the way the interloper, space probes, and other objects held together by chemical bond. Instead they flex changing shape as the direction to the tide producing object changes. Planets may technically be held together by chemical bonds at the local level but it's basically never enough to resist the huge loads induced over anything larger than an asteroid. The real life size ash/ember twin would either shatter eachother into a minature planetary disk or one would rip the other apart into a new ring. That brings me to my final issue. Even if we make the rest of the planet have internal strength to resist bring torn apart (say some sort of constructed megastructure) and put that planet within the roche limit so the sand can be lifted off the planet. In fact the sand would form a ring around the planet it was orbiting with a buldge around the area of the megastructure the sand got pulled off of. The sand will never hit the other planet. This is why the in game sand column has a huge force of friction to force you to almost match its speed. If it didn't you'd just be thrown into orbit between the two planets when you got lifted up by the sabd column.

“I didn’t really believe the hourglass twins were possible, so I scoured the universe to find a real world example. And to my shock, I found hourglass twin stars”

well, firstly, for mimicking the hourglass twins, the overall density of the planet would need to shift aswell. having an impossibly dense core with low density sand would be a part of it, as well as a third body to overcome inevitable balances that form.

I might try make a model of this tbh. I think alternating sand could be done via orbit around a star. If the system has an eccentric orbit it Coyle possibly alternate which object has a stronger gravity Then again, in the outer wilds universe they have gravity manipulation which could be a factor in this tbh

wake up babe new peak just dropped

Dude, I need someone to make a simulation of this on Space Engine

As a Kirby fan, i am VERY familiar with the Roche Limit lol

Sorry man, but the thumbnail doesn’t have enough red circle to draw my attention to the 2 planets

Crazy how life in the universe and sand pillar planet have basically the same likelyhood

The red splotch on Charon is called Mordor

The asteroid Arrokoth (aka Ultima Thule) is basically this, two smaller asteroids that slowly got closer and finally "kissed"

Red Clickbait Arrow is the best

So isn’t the gravity reader based on Timber Hearths gravity? It may not line up with earths gravity and the metrics we use here, if the gravities of the twins were lower than you calculate would that make them more plausible?

good!

I think if you get a gas giant near a smaller moon (such that the L1 is sub surface to the smaller Moon) [pretty much the definition of a roche limit] it'll end up shredding the smaller moon and you'll end up with a ring system eventually. I enjoy the moon 'Pan' of Saturn, because it's sitting in the ring system absorbing some of the ring itself.

herm acxually a planet's definition is "A celestial body that orbits the sun, has sufficient mass to assume nearly a round shape, clears out dust and debris from the neighborhood around its orbit, and is not a satellite of another planet" meaning any celestial body outside the solar system is not considered a planet additionaly any bynary system is by default excluded from the definition due to not having cleared its orbit neighborhood

1:40 ouch

been a while since i played but i assumed the sand transfer was due to the energy being gathered from the sun energy has mass and all that meaning that a large enough collection of energy would generate gravity as well

Pluto was demoted from a planet to a dwarf planet because it had not cleared its neighborhood of other objects (like Charon). So I think part of the reason it’s a dwarf planet is because it is a binary planet system. There might be other objects too though.

7:55 you could also just see if you fly off into space by simply standing on the surface before the transfer begins since you don't, a loose particle wouldn't fly off due to gravitational forces

Im here for the red clickbait arrow tbh

Good shit

I don’t actually plan to stick around to watch this video, but I wanted to give you credit for the clickbait arrow in the thumbnail

i think due to how fast everything is moving in the game it doesnt really make sense. i imagine the only way would be the orbit of the planets around each other would have to be super slow and which ever side was closer to the star might create like a gravity multiplier to shift the sand torward which ever planet was closer to it in the orbit?

Thought it was Spore from the thumbnail lol

Hell yeah science

Couldn't we also take into account the gravity of the sun pulling on the sand? If we assume that the planets orbit each other slow enough that one planet remains closer to the sun for long enough that the planet farther away transfers its sand to the smaller planet, then as they continue to orbit around the sun and each other, the now smaller planet ends up closer to the sun, and it pulls the sand back.

There is a novel called “Rocheworld”

Clicked because of “red clickbait arrow” Bravo

i always assumed that outer wilds planet system was loosely based on the Trappist 1 system

Have you considered that the gravitational constant in the outer wilds universe is likely much larger? A few km large star can maintain fusion for example

I think that you could have this by having the planetcwith the sand spin on it's axis extremely fast. this would effectively lower the total gravity, allowign trhe other planet to pull the sand off of the spinning planet, and due to it's rotational speed, it loses momentum as sand is pulled off. the sand then adds very small amounts of momentum to the planet which the sand is going towards, which means that planet will end up spinning faster. this leads to the planet having enough rotational speed for this to occur again, and again, etc.

Idea, sand tide.

i read the title as "how realistic are the hourglass twinks?"...😶😭

Doesn't the Ash Twins change gravity depending on how much sand they have...?

' How terrifying would it be if Earth becomes an hourglass twin due to an incomprehensible planet of unknown compositions suddenly appearing right next to Earth without disrupting the whole solar system... It then begins to first extract all the resources that sustain life on Earth before extracting what is left of life to this unknown planet ' - Chrome

"Hmm, 2 planets constantly transmitting matter between one and the other in a video game, I think it will be an amazing idea to spend hours of my life doing the maths to see if it's possible." (jk the video is amazing)

I have access to matlab, ill run some numbers and look up the starcharts, maybe we will find the outer wilds solar system lmaooo.

Hello! Your immense inteligence does not tell you that the barycenter of the two objects possess an equalized gravity of both planets, meaning the gravitational force is zero between the two planets measured at the barycenter. This means by the time the pulled sand gets there, it might be able to pass the barycenter out of shear momentum, especialy if the barycenter's mass is closer to the other planet due to it pulling the sand in the first place. My other theory is that the sand is in a semi balanced state which can be pushed through by tidal effects, and in the moment the state breaks, the sand just launches towards the other planet due to for example magnetic sand maybe, i am no physicist. Also Earth in real life itself throws its atmosphere into the sky too, but i am not sure wether Moon falls into that immense jet sometimes, or not

fwiw, the gravity in-game probably isn't the *best* thing to gauge off of, because when you jetpack it claims you're in 0-gravity immediately, which is obviously false since you just fall back to the surface. But it's probably good enough to use anyway for a goofy theory like this.

Remember that's not Earth's gravity. But you could calculate it in comparison to Earth's. 7:29

Why can't I turn off the subtitles? Personally, they're distracting. Why not have them as part of the KZfaq subtitles system instead of part of the video?