In celestial mechanics, the Roche limit, also called Roche radius, is the distance from a celestial body within which a second celestial body, held together only by its own force of gravity, will disintegrate because the first body’s tidal forces exceed the second body’s gravitational self-attraction. Inside the Roche limit, orbiting material disperses and forms rings, whereas outside the limit, material tends to coalesce. The Roche radius depends on the radius of the first body and on the ratio of the bodies’ densities.

The term is named after Édouard Roche, the French astronomer who first calculated this theoretical limit in 1848.

Explanation

The Roche limit typically applies to a satellite’s disintegrating due to tidal forces induced by its primary, the body around which it orbits. Parts of the satellite that are closer to the primary are attracted more strongly by gravity from the primary than parts that are farther away; this disparity effectively pulls the near and far parts of the satellite apart from each other, and if the disparity (combined with any centrifugal effects due to the object’s spin) is larger than the force of gravity holding the satellite together, it can pull the satellite apart. Some real satellites, both natural and artificial, can orbit within their Roche limits because they are held together by forces other than gravitation. Objects resting on the surface of such a satellite would be lifted away by tidal forces. A weaker satellite, such as a comet, could be broken up when it passes within its Roche limit.

Since, within the Roche limit, tidal forces overwhelm the gravitational forces that might otherwise hold the satellite together, no satellite can gravitationally coalesce out of smaller particles within that limit. Indeed, almost all known planetary rings are located within their Roche limit. (Notable exceptions are Saturn’s E-Ring and Phoebe ring. These two rings could possibly be remnants from the planet’s proto-planetary accretion disc that failed to coalesce into moonlets, or conversely have formed when a moon passed within its Roche limit and broke apart.)

The Roche limit is not the only factor that causes comets to break apart. Splitting by thermal stress, internal gas pressure and rotational splitting are other ways for a comet to split under stress.

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I can write stupid fanfiction right?

Im not above fanfiction? Id be lying if I said I didn’t want to

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People write a lot of bad shit. Write your shit, it’ll probably be better than average

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True, very true. I mean, its just wholesome stuff, revolution (lmao depression), and governments stuff. And its fun for me, so yeah. Im just overreacting lol.

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It’s easy to shoot yourself down, it’s hard to ignore the impulse to do so

I want you to write your fanfiction so that you do better than I do in dealing with those feelings

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Write it and also share it with me I wanna read

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:hahaha: IM NEVER GOING TO FINISH BECAUSE MY STANDARDS ARE IMPOSSIBLY HIGH!!!

NYAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

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:screm:

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12 points

All fiction is fanfiction. No one has had an original idea for a novel since the Epic of Gilgamesh.

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thats…

wow

you’re right lol

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10 points

yeah. fanfiction is cool. what do you want to write?

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fanfic for a show named “amphibia”, Im in the current habit of inserting my far-left ideology into absolutely everything. I can go into more detail if you’d like, but yeah. I just feel bad that I’m not reading theory, or history, or watching. Just being unproductive and writing random shit about revolution.

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5 points

hell yeah! sneak in leftist propaganda to the children. or just have a good time. or both!

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I wrote one for the Netflix cartoon Dogs in Space and I just lifted that copy pasta about Yuri Gagarin.

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Do it, be cringe! Embrace it!

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5 points

i started writing fanfiction this year and it’s so much fun

do it!!

:duck-dance:

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4 points
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Deleted by creator
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:wojak-nooo:

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29 points
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New Megathread Nerds!!! :posting: doing homework thats due in 1 hour while vibing to kirby music :cat-vibing:

@aaaaaaadjsf @Abraxiel @Acute_Engles @AnarchaPrincess @Antilope @Alaskaball @BrookeBaybee @bbnh69420 @buh @CARCOSA @cawsby @CDommunist @Cheesewizzard @Cherufe @ClathrateG @ClimateChangeAnxiety @clover @comi @Commander_Data @COMMENT @ComradeCmdrPiggy @ComradeEchidna @context @congressbaseballfan @corgiwithalaptop @crime @Cromalin @CyborgMarx @Dawn_Beveridge @DinosaurThussy @Diogenes_Barrel @Dirt_Owl @Donut @drinkinglakewater @Eco @ella @ElGosso @el_principito @EmmaGoldman @FidelCashflow @Flinch @flowernet @forcequit @Frogmanfromlake @GalaxyBrain @ghosts @Goadstool @GorbinOutOverHere @GoroAkechi @Grownbravy @GVAGUY3 @HarryLime @hexaflexagonbear @HoChiMaxh @Hohsia @Ideology @JamesConeZone @Kanna @Kaputnik @Koa_lala @kristina @KiraNerys @LesbianLiberty @marxisthayaca
@MaxOS @MaybeNickCage @MelaniaTrump @Mindfury @Nakoichi @Ness @PM_ME_YOUR_FOUCAULTS @PorkrollPosadist @President_Obama @PurrLure @Ram_The_Manparts @Redcuban1959 @REallyN @RNAi @RoseColoredVoid @solaranus @SorosFootSoldier @Sickos @silent_water @Sphere @Spike @spring_rabbit @take_five_seconds @TankieTanuki @Tervell
@TheSpectreOfGay @ThisMachinePostsHog @ultraviolet @UlyssesT @Venustum @viva_la_juche @WhyEssEff @WIIHAPPYFEW @wtypstanaccount04 @Yanqui_UXO @Zoift

@thelastaxolotl @WhoaSlowDownMaurice @Quimby @Lydia

Remember nerds, no current struggle session discussion here on the general megathread, i will ban you from the comm and remove your comment, have a good day/night :meow-coffee:

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Kirby is my all time favorite game character I think

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6 points

Howdy :deng-cowboy:

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Hi from Eugene, Oregon!

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6 points

:debs:

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:andropov-wave:

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4 points

:congratulations:

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3 points
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Been touching grass the past few days with a local org and it’s been nice! I’ll be back to horror movie posting tomorrow <3

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new mega noice

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3 points
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Is this game any good?

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23 points

Its cool that celestial bodies arent solid wholes, but rather a goopy mess of stuff thats only solid because it’s all held together by its own gravity pulling everything together. Neat

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15 points

same tbh

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17 points

Lmaooo vibes

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Thats basically all matter

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5 points

I relate

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23 points

:NOOOOO: :We… We are Breaking Bad™.

:jesse-wtf: :We Better Call Saul™.

Bravo Vince Gilligan :amerikkka-clap:

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22 points
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CoD games do be getting more and more insane, Iran is controlled by Al-Qaeda and are connected to Mexican drug cartels smuggling weapons in the Netherlands? :wut:

You shoot up a street in Amsterdam, point guns at civillains to “de-escalate”.

Also, the evil Russia is working with Iran obviously.

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12 points
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12 points

Are we just gonna gloss over the intro literally being a proxy for the murder of Soleimani?

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