A Black Hole's Spinning Heart of Darkness

sciencehabit writes "Like all invisible things that are only partly understood, black holes evoke a sense of mystery. Astronomers know that the tremendous gravitational pull of a black hole sucks matter in, and that the material falling in causes powerful jets of particles to shoot out of the hole at nearly the speed of light. But how exactly this phenomenon occurs remains a matter of conjecture, because astronomers have never quite managed to observe the details – until now. Astrophysicists have taken the closest look to date at the region where matter swirls around a black hole. By measuring the size of the base of a jet shooting out of the supermassive black hole at the center of the M87 galaxy (abstract), the researchers conclude that the black hole must be spinning and that the material orbiting must also be swirling in the same direction. Some of the material from this orbiting 'accretion disk' is also falling into the black hole, like water swirling down a drain."

Comments

approximately 3 billion solar masses

[MRe_nl]

concentrated in a region at the galactic core that is only about the size of the Solar System.

http://csep10.phys.utk.edu/astr162/lect/active/smblack.html

Re:Fascinating

[Baloroth]

The jets don't come from inside the black hole at all, they are a result of the interaction of the black hole and the disk of matter falling into it. The exact mechanism for their production isn't certain yet, but the simple explanation is that as the matter gets close to the disk, it spins faster and faster while losing energy (since it is falling into a negative gravity well) which can be focused into some few particles (through magnetic effects or possible relativistic "frame dragging") that are then propelled outwards well before they reach the event horizon. The evaporation is more complex and I don't understand it so I won't try to explain it.

Attempting to explain the universe through electro-magnetism alone is... a useful exercise, but also really not true, and demonstrably so. Gravitation effects are radically different from electrical ones. You can alter electrical theory to fit the observations, but only if you introduce arbitrary new rules and exceptions, which is, if not exactly forbidden in science, at the least extremely questionable (and the more complexities you have to introduce the less likely your theory is to be accurate). Gravitational theory, on the other hand, proceeds from and naturally fits with the observations. Now, it is well known in physics that our understanding of gravity is incomplete (classical and quantum theories do not agree, for one thing, despite both seeming to be true on their respective scales), but to argue that because gravity is "weak" it cannot also be the strongest force en masse (so to speak) is, well, faulty logic. There are numerous examples of weak things aggregating to provide effects well outside their individual strength. When we say electrical forces are "stronger" than gravity, we mean only on a certain scale (atomic, to be specific). Over they scale of a few feet, the nuclear force is nonexistent, despite the fact it is even stronger than the electrical force on small scales.