this post was submitted on 17 Aug 2023
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Astronomy

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The largest Black Hole compared to Our Solar System

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[–] [email protected] 16 points 1 year ago (1 children)

Is there a banana for scale or does Lemmy use a different model for scale? Beans?

[–] [email protected] 27 points 1 year ago (1 children)

I think all the bananas (and beans) are already in the picture

[–] [email protected] 4 points 1 year ago

Well, even the picture is in the picture..

[–] [email protected] 14 points 1 year ago (2 children)

And it has a density of only about 3g per cubic meter. It's not much denser than a vacuum made with a mechanical pump.

[–] [email protected] 7 points 1 year ago (1 children)

That's the thing about black holes that always blows my mind. I don't understand how the larger a black hole is, the less dense that it is. In my mind, I always think of black holes as super dense objects containing so much matter in such a little space that the gravity is crazy strong. How can something so not dense be a black hole? It doesn't make sense to me!

[–] [email protected] 7 points 1 year ago (1 children)

To be fair, the density is calculated from the event horizon, which is a somewhat arbitrary boundary. All the mass is still concentrated at the singularity which is still infinitely dense, just... a bit more so.

[–] [email protected] 5 points 1 year ago

Ah, I didn't realize that. I guess that's a little more terrifying. Sounds like you could pass the event horizon and not be instantly crushed, but would have no way of ever escaping. You'd just eventually get sucked into the singularity.

[–] [email protected] 4 points 1 year ago (1 children)

Hiw stable is this kind of density? Is it going to shrink over time?

[–] [email protected] 6 points 1 year ago (1 children)

Not really. If more material falls in, its mass and size increases (the volume increases faster than the mass, which is why it's so unexpectedly low density in the first place), but otherwise it just sort of sits there.

Over the very long term, it will evaporate away by Hawking radiation. But that's a very very slow process. Like, long after everything else in the universe has ended.

[–] [email protected] 1 points 1 year ago (1 children)
[–] [email protected] 4 points 1 year ago (1 children)
[–] [email protected] 3 points 1 year ago

...and thennnn??

[–] [email protected] 5 points 1 year ago (1 children)

That's actually smaller than I would have thought. I wouldn't have expected our solar system to even be visible in comparison.

[–] [email protected] 12 points 1 year ago (1 children)

What the hell are you talking about, that thing is beyond comprehension.

[–] [email protected] 8 points 1 year ago (1 children)

We shouldn't downvote people when they realize they have been thinking about something the wrong way and admit it.

[–] [email protected] 1 points 1 year ago (1 children)

Did I miss something? I didn't down vote them

[–] [email protected] 1 points 1 year ago

Not you I'm sure, but they were at 0 when I posted, so thought I'd note it.

[–] [email protected] 4 points 1 year ago

Lucky for us, it is to far away.

[–] [email protected] 4 points 1 year ago (2 children)

How big is this, in real numbers?

[–] [email protected] 11 points 1 year ago (1 children)
[–] [email protected] 3 points 1 year ago

That's technically correct.

[–] [email protected] 6 points 1 year ago (1 children)