Andromeda has an extended halo of red stars, Puragra (Raja) Guhathakurta of the University of California, Santa Cruz, announced at an American Astronomical Society meeting in Seattle.
Galaxies have a central bulge, which falls away fairly rapidly, & a ring (disc) of stars around that, & finally a “stellar halo” with a much wider distribution.
Astronomers have been looking for “halo” stars like this for quite some time, & Andromeda seems to have come good for them, big time.
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