Ask Ethan: Why Doesn’t Every Galaxy Have A Supermassive Black Hole?“[You’ve said
Ask Ethan: Why Doesn’t Every Galaxy Have A Supermassive Black Hole? “[You’ve said] that most galaxies have a supermassive black hole at the center. I heard the same statement on television this morning. But why would any galaxy not have a supermassive black hole? Do astronomers know for certain that some galaxies lack a black hole at the center – that there’s a hole (so to speak) where the black hole ought to be?” Every galaxy, at least at one point, had gas, stars, and had those early stars die. Stellar deaths lead to black holes, and black holes accrete matter, grow, merge, and sink to the centers of galaxies, where they grow further. After billions of years of cosmic history, there should be at least one black hole within each galaxy that’s gotten very large.Therefore, every galaxy that exists today should have at least one supermassive black hole, right? No, not right. Come find out the fascinating story behind why. -- source link
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