About 2 billion years ago, the Andromeda galaxy cannibalized one of the largest galaxies in our galactic neighborhood, stripping it of over 90% of its mass (~23 billion solar masses) and leaving behind a dense core that is now known as M32.

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About 2 billion years ago, the Andromeda galaxy cannibalized one of the largest galaxies in our galactic neighborhood, stripping it of over 90% of its mass (~23 billion solar masses) and leaving behind a dense core that is now known as M32.