From my understanding, black holes are extremely dense collapsed held together by gravity. They grow by taking in more mass, which increases their gravity. However, this intook material, and already existing material within the black hole still hold magnetic properties, and these materials are often tightly packed with other materials they would usually repel. (Think of it as holding two north sides of magnets together). The only thing that keeps these particles from flinging each other apart is the force of the gravity field, which holds everything together. However, black holes lose mass through Hawking Radiation, which means that they lose gravity as well. Eventually, the gravitational force of a black hole will begin to equal or become less than the magnetic forces, in which case the black hole will fling itself apart in a Alderaan-esque explosion.(This process takes a while, however. A LONG while.)

So, in essence, that’s how stuff can escape a black hole. Also, there is no universal speed limit.

I recommend “The Universe in a Nutshell”, by the way. Not exactly a cosmology book, but it’s VERY helpful.

There are a few things I don’t understand. Nothing is supposed to escape the gravity of a black hole, not even light. How do they explain “cosmic jets erupting from a supermassive black hole” and “particle jets that emanate from the black hole”.

This quote might be a more accurate description: “These jets arise as infalling matter approaches the black hole”

And the mass, 55 million stars worth. Where did that come from if a black hole is the result of the collapse of a single massive star? 55 million stars are the equivalent of 550 globular clusters at around 100,000 stars each. This thing must have been sucking up matter for a very long time.

When black holes were first theorized, it was said that their mass was equal to 50,000 tons- in a matchbox. I think it’s much more than that now. It boggles the mind.

Time to buy a ‘current’ cosmology book.

No. The Edit wasn’t there, either. So we have to refresh the page by clicking on the Forum name to make Edit appear and allow our posts to open up. But it still doesn’t explain why, when I clicked reply to ER’s post, it went up under my original one. Maybe I goofed. I’ll watch that in future and see if it happens again.

It has something to do with conservation of angular momentum in spinning bodies. I never understood the math myself, but I believe that the multiple collisions of particles in gravitationally collapsing discs tends to smooth out the velocity distributions of the component particles into two distinct groups, those in the plane or rotation, and those at right angles to it. The latter (the jets) is bi-modal, one up and one down.

I’m not quite sure how or why this happens, but I understand it is simple Newtonian mechanics at work, no fancy relativistic effects are involved.