Q&A: Black Holes

Q:
I have a question on the latest explanation on the black hole NGC 3783 and surrounding gas. How can the gas fall into the black hole while it is blown away from it at high speed? It looks more like a "white hole" where matter is ejected

A:
Life is complicated, and so are galaxies with black holes in them. The material near the event horizon, say a few (~10) Schwarzchild radii, or in this case, about the radius of the Earth's orbit around the Sun, is probably in a disk that is feeding the black hole. The energy from this accretion process generates an enormous amount of power in the form of X rays and other type so light. This radiation flows out in all directions. A portion of it is absorbed in a gas cloud that is about a million Schwarzchild radii away (about a light year, or 100,000 times the radius of the Earth's orbit), and causes this cloud to expand. So, material close in to the black hole is falling in, and generating power that causes material farther out to expand.