M87 possesses an enormous number of tightly packed star clusters called globulars. Whereas the Milky Way has about 160 known globular clusters M87 boasts some 10,000. Moreover, M87’s center has a black hole that dwarfs the Milky Way’s, weighing six billion to seven billion times more than the sun, over a thousand times as massive as the four-million–solar mass black hole occupying the Milky Way’s center…

If M87’s black hole actually consists of two black holes orbiting each other, they could fling away a star cluster that strayed too near. The cluster’s gravity causes the two black holes to get a little closer together, making them lose orbital energy that gets transferred to the star cluster.

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