Signatures of the M31-M32 Galactic Collision

  title={Signatures of the M31-M32 Galactic Collision},
  author={M. Dierickx and Laura Blecha and Abraham Loeb},
  journal={The Astrophysical Journal},
The unusual morphologies of the Andromeda spiral galaxy (M31) and its dwarf companion M32 have been characterized observationally in great detail. The two galaxies' apparent proximity suggests that Andromeda's prominent star-forming ring as well as M32's compact elliptical (cE) structure may result from a recent collision. Here we present the first self-consistent model of the M31-M32 interaction that simultaneously reproduces observed positions, velocities, and morphologies for both galaxies… 

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