11 points

Okā€¦ soā€¦

  • Pull you in with the power of gravity

Does not ā€˜suckā€™ you in with the power of a vacuumā€¦

About right?

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1 point

You fall into gravity wells, they donā€™t suck you.

Best way to understand is to get the mental image of spacetime as a 3d sheet like grid, where each object pushes down on it and creates a pit, or well. The bigger the object the deeper the well, and the more force you will need to stop yourself from sliding towards the object and propelling yourself back up the slope.

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9 points
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Eh thats kinda nitpicky. For non physics people ā€œsucking in with lots of forceā€ is good enough to describe ā€œabsurdly strong gravitational pullā€. Its not a myth, its an over simplification.

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3 points
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I think the point the article was trying to make is that ā€œsucking in with lots of forceā€ does not really happen any differently outside the event horizon of a black hole than it would in the proximity of any other star (or object) with the same mass.

So itā€™s addressing the ā€œmythā€ that being in the proximity of a black hole would inevitably suck you inā€¦ however, odds are that if you are not directly aiming for the black hole, even if you did not resist, you would just end up entering an orbit around it, the same way we are currently orbiting the Sun. Or maybe even be catapulted out of it, instead of sucked in.

The difference would be that past the event horizon you would be torn apart by the space distortion (instead of being cooked alive if it were a star). But theoretically if you can avoid crashing into a star, then you can avoid entering a black hole.

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2 points

does not really happen any differently outside the event horizon of a black hole

I mean, thatā€™s a pretty big caveat, given that strength of the gravitational force in the object was big enough to create the event horizon in the first place

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2 points
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Yes, but thatā€™s very localized and itā€™s not the same as the image some people have of black holes characterizing themselves for instantly sucking it all in its vecinity.

If the teachings donā€™t reach outside the classroom, you wouldnā€™t say that people outside can learn more standing there than they would from any other similarly looking room. For a black hole, the gravitational pull over everything that you can see around it is the exact same as it would for a lower density equivalent mass you might be orbiting.

And we know there are stars heavier than some black holes, which actually would have a stronger pull to things in their proximity than if they were a black hole with smaller mass. Also Stephen Hawkins introduced the concept of micro/mini black holes. He theorized that the minimum mass for a black hole is in the order of 0.00000001 Kg. What makes a black hole have a singularity has more to do with its density than its mass, so if you could smash together a mass with enough strength you could cause it to collapse.

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2 points
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Itā€™s exactly the same gravitational pull as the star that previously collapsedā€¦ (And Iā€™ve not read the article (yet), this is just a personal nitpick that Iā€™ve had for a LONG time).

ā€“edit after reading the articleā€“

In terms of inevitably falling into a black hole, itā€™s only the material that formed interior to three times the event horizon radiusā€Šā€”ā€Šinterior to whatā€™s known as the innermost stable circular orbit (ISCO) in general relativityā€Šā€”ā€Šthat would inexorably get sucked into it. Compared to what actually falls into the event horizon in our physical reality, the purported ā€œsuckingā€ effects are nowhere to be found. In the end, we have only the force of gravity, and the curved spacetime that would result from the presence of these masses, affecting the evolution of objects located in space at all. The idea that black holes suck anything in is arguably the biggest myth about black holes of all. They grow due to gravitation, and nothing more. In this Universe, thatā€™s more than enough to account for all the phenomena we observe.

That summary explains it better than I can.

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1 point

I disagree. It is more than just a nitpick. Saying black holes suck things in implies that they are doing something different than any other mass. Which they are not. Would you say a star sucks in stuff around it? Or a planet? Or moon? No. That sounds absurd. It makes it sound like blackholes are doing something different to everything else - which is miss-leading at best. They way things are described matter as it paints a very different picture to the layman.

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1 point

Would you say a star sucks in stuff around it? Or a planet? Or moon?

For a star, I absolutely would. For a planet or moon, it depends on the context.

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0 points
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Would you say our planet is currently being sucked in by the Sun? or would you rather say that we are just orbiting the Sun?

Because odds are that if you approach a black hole without aiming directly for it, you might just end up in an orbit around it, not unlike we currently are around the Sun. Or you might even be catapulted out, instead of being ā€œsucked inā€ in the popular sense.

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6 points

Pedantry, thy name is this article.

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:nerd:

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5 points

Well there goes my dream of getting sucked off by a black hole!

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3 points

and donā€™t dismiss the bragging rights for being that guy with the longest penis ever

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3 points

Universeā€™s longest needle dick.

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Sounds like you can still get pulled by a black hole though!

Pulling, when done well, can be as nice and effective as sucking, and Iā€™m sure black holes have a lot of experience in pulling things.

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5 points

Anyone else get the impression itā€™s a slow news day?

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