New Evidence of Cannibalism in Andromeda

A survey of the nearby Andromeda galaxy and its surroundings has confirmed that the giant spiral is consuming a previously known satellite galaxy. In addition, the study found 14 clusters of stars that appear to be the cosmic fossils of other small galaxies long ago devoured.

The work supports the prevailing view that large modern galaxies, including our Milky Way, built their bulk through a form of cannibalism, acquiring the stars of smaller galaxies over billions of years.

Around Andromeda is a vast halo of stars is thought to be leftovers from the giant construction project. At first glance, the halo appears to have smooth structure, with stars evenly distributed. Upon closer inspection, the halo is riddled with substructure from past interactions with smaller galaxies.

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http://www.space.com/scienceastronomy/RAS_andromeda_canibal_040331.html

That was a very strange headline for that story. Things don't happen very quickly on that scale -- they have to be dramatized.

they're everywhere!