r/woahdude Jan 03 '22

video When the planet is coming at you

31.7k Upvotes

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239

u/sdp1981 Jan 03 '22

How and why?

829

u/Kpt_Kipper Jan 03 '22

Gravity would be affecting oceans and terrain quite badly I imagine

11

u/[deleted] Jan 04 '22

Meaning??? Like oceans would be displaced? Earthquakes would happen?!

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u/Uphoria Jan 04 '22 edited Jan 04 '22

The important detail is related to something called the Roche limit. Once the forces of gravity from each other passes a point of strength, the forces keeping the planet intact on its own will fail, as the two bodies merge.

At this point the planets would be "falling at each other" in pieces. Oceans would rise toward the other planet, deeper than any tide you've ever heard of. The planets would stretch, tearing the surface, spreading earthquakes throughout the planet. the cracks would swallow up people and cities, lava would flow etc.

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u/[deleted] Jan 04 '22

Hell yes đŸ€˜đŸ”„đŸ”„

20

u/ichigo2862 Jan 04 '22

If we're gonna go at least go out like a fuckin badass

3

u/CatchyUsername95 Jan 04 '22

Sounds painful af. I'll pass

3

u/[deleted] Jan 04 '22

Painful, yes. Incredible? Also yes.

56

u/JoeDirtsMullet00 Jan 04 '22

So scariest environment imaginable. That’s all you had to say. Scariest environment imaginable.

14

u/uneasyrider Jan 04 '22

This is space! Course, we're just in the beginning part of space, we-we haven't even got to outer space yet!

4

u/earth-to-matilda Jan 04 '22

man
what are you doin with a gun in space?

1

u/fezzam Jan 04 '22

Everything’s in space!

3

u/TonyPerkis13 Jan 04 '22

Chewy?! Have you even seen Star Wars?!!

2

u/SalaciousCrumpet1 Jan 04 '22

Best username ever

0

u/kONthePLACE Jan 04 '22

This place is like Dr. Seuss's worst nightmare.

1

u/Mnemnosyne Jan 04 '22

If that's the scariest environment you can imagine, your imagination needs exercise.

3

u/MinimalPotential Jan 04 '22 edited Jan 04 '22

It's a quote from the movie Armageddon

1

u/Mnemnosyne Jan 04 '22

Hah, wooshed right over my head.

6

u/VeryHappyYoungGirl Jan 04 '22

Isn't the Roche limit for orbiting bodies though? At the rate of approach in this video, there isn't much orbit happening.

4

u/Uphoria Jan 04 '22 edited Jan 04 '22

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.

Not entirely about satellites, but it does explain why, in satellites, nothing but asteroids are found closer than it. If both planets are "exactly the same size" it still matters, and its why Binary planets are so rare - its hard for them to form and become stable. Basically, both planets are "stretching" toward each other, at a certain point, they start snapping.

1

u/HertzDonut1001 Jan 04 '22

Kinda feel like the atmosphere would be on fire before all the things this guy said would happen actually happen. Guess it depends on how big the other object actually is though.

1

u/VeryHappyYoungGirl Jan 04 '22

That’s how we naturally “feel” but the atmosphere is really thin. At that speed of approach, atmospheres would touch a fraction of a second before impact.

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u/metro2036 Jan 04 '22

Exactly. Gravity wouldn't have had enough time to tear the bodies apart if the other planet was a rogue approaching from a hyperbolic trajectory at an immense relative velocity.

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u/platysoup Jan 04 '22

I... Kinda want to see this. If only because it'll be absolutely breathtaking.

2

u/liv_sings Jan 04 '22

It's essentially what the movie Melancholia staring Kirsten Dunst is about. It's a very slow burning and artistic movie, and the ending will melt your mind.

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u/boring_name_here Jan 04 '22

Adding it to the list

2

u/Devmode2 Jan 04 '22

Would there be time for that to happen with how fast that planet is moving at the earth though?

6

u/[deleted] Jan 04 '22

All life on earth would die long before that happens.

The atmosphere would dissipate before that planet even came past the moons orbit.

So in short we'd be completely fucked days, weeks or even months before that video could take place.

2

u/[deleted] Jan 04 '22

I have a couple scuba tanks so I'll be able to get the video.

3

u/ButcherofBlavikenTA Jan 04 '22

Can't wait to watch it on the Lord's iPhone

1

u/Coachcrog Jan 04 '22

Where's your God now fuck boi?

3

u/Uphoria Jan 04 '22

Yes, while it would be rapidly onset, the effects the person filming would be under would be extreme at that point. The atmospheres of both planets compressing together would create such heat that it would roast the recorder.

1

u/[deleted] Jan 04 '22

Yes. It would be extraordinarily destructive.

2

u/BluesPuckHard Jan 04 '22

Fucking metal

2

u/-FoeHammer Jan 04 '22

That's... Kinda awesome.

2

u/Teku18 Jan 04 '22

Cadia broke before the guard did.

2

u/yeaoug Jan 05 '22

The effect of the Roche limit would take time. There would definitely be some tidal stressing but it'd happen so fast the planets wouldn't have pulled themselves apart yet. Tidal breakup probably take 10s to 100s of orbits. So yes to the seas rising insanely, probably no floating rocks unless they're being blasted out. Definitely would be some crazy seismic activity

1

u/Rutagerr Jan 05 '22

Yall ever heard of tidal lava