Astronomers Spot a Black Hole the Size of Jupiter Wandering Across our GalaxyComments
An_Old_Big_Tree OP wrote
They come way smaller! It says so in the article. Like a few kms across.
mofongo wrote
That's seriously compressed. I always thought black holes were star-sized at the minimum. I learned something now today 😄
sudo wrote
Yep. The size of a black hole depends directly on its mass. If you had a black hole that was the same mass as the Earth, it would be 1.77 centimeters from end to end.
And really, that's just what's called the "event horizon" of the black hole, which is the part where nothing can ever escape from. All of the mass is actually in the very center, and it's infinitely compressed. So, in that sense, black holes don't actually have any volume at all.
Here's the Wikipedia page on it, if you're interested.
mofongo wrote
That's quite small for a black hole.