A black hole with three billion times the mass of the Sun has been found hurtling out of its parent galaxy at 8 million kilometers per hour! What could give it that kind of incredible boost? Turns out, it’s something even more incredible: the two supermassive black holes that merged to form it in the first place.
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In astronomy, you deal with a lot of ridiculously violent cosmic phenomena. Stars explode, asteroids collide, whole galaxies smash together. When you look at the math and physics, when you actually grasp the levels of power involved, it’ll make the hair on the back of your neck stand up. It’s chaos wielded on a mind-crushing scale.

And then there’s the “two supermassive black holes colliding and merging and then launching the resulting even larger billion-solar-mass black hole out of a galaxy at nearly 8 million kilometers per hour due to gravitational waves” scale of immensity.

Source: A 3 billion solar mass black hole rockets out of a galaxy at 8 million kilometers per hour. Yes, seriously.