I'm not in any way qualified to comment on black holes, but it was my understanding that nothing could escape its grasp, including light. (hence the black hole) So what gives, how can it emanate sound waves?
The Hole is not emananting souds waves per se. Material hitting the event horizon does so with enormous energy, some of that causes huge shock waves in surrounding gas/dust. This is what Chandra is seeing.
This wave is coming from the edge of the black hole? So there is a point where matter can escape. This must be similar to the images of a black hole venting. The force of the excess matter being shifted aside must be greater then the force drawing the rest in.
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