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Can a Black Hole Swallow a Galaxy?

-- | December 15, 2012

Question: I know that black holes are very dense and their gravitational pull is so strong no one really knows what they look like because they don’t come out alive. I have read that there might be one in the center of galaxies well why doesn’t it suck the Milky way galaxy in? — Lily

Answer: It is a matter of relative scale. Galaxies are quite large; many kiloparsecs in size, while black holes are quite small, only a few millionths of a parsec (a parsec is about 206265 Astronomical Units, where an Astronomical Unit is the distance from the Earth to the Sun). A single Black Hole, even one at the center of our Milky Way galaxy, is just too small to eat an entire galaxy.

Jeff Mangum

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