A giant stream of metal-rich stars in the halo of the galaxy M31

  title={A giant stream of metal-rich stars in the halo of the galaxy M31},
  author={Rodrigo A. Ibata and Michael Irwin and Geraint F. Lewis and Annette M. N. Ferguson and Nial Tanvir},
Recent observations have revealed streams of gas and stars in the halo of the Milky Way that are the debris from interactions between our Galaxy and some of its dwarf companion galaxies; the Sagittarius dwarf galaxy and the Magellanic clouds. Analysis of the material has shown that much of the halo is made up of cannibalized satellite galaxies, and that dark matter is distributed nearly spherically in the Milky Way. It remains unclear, however, whether cannibalized substructures are as common… 
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Galactic Halo Substructure in the Sloan Digital Sky Survey: The Ancient Tidal Stream from the Sagittarius Dwarf Galaxy
Two studies have recently reported the discovery of pronounced halo substructure in the Sloan Digital Sky Survey (SDSS) commissioning data. Here we show that this halo substructure is, almost in its
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THE presence of unseen haloes of 'dark matter' has long been inferred from the high rotation speeds of gas and stars in the outer parts of spiral galaxies1. The volume density of this dark matter
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We present a detailed prescription for how galaxy formation can be modelled in hierarchical theories of structure formation. Our model incorporates the formation and merging of dark matter halos, the
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Tidal disruption of the Magellanic Clouds by the Milky Way
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Stellar content of nearby galaxies. II. The Local Group dwarf elliptical galaxy M32
Using the CCD camera on the Canada-France-Hawaii Telescope, color-magnitude (C-M) diagrams were obtained for brightest stars of the Local Group dwarf elliptical galaxy M32. Both the I vs (V-I) and I
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The Disruption of the Sagittarius Dwarf Galaxy.
Numerical simulations of dwarf spheroidal galaxies undergoing several close encounters with the Milky Way are described. By comparing our models to observed properties of the recently discovered
Ring structure and warp of NGC 5907: Interaction with dwarf galaxies
The edge-on, nearby spiral galaxy NGC 5907 has long been used as the prototype of a “noninteracting” warped galaxy. We report here the discovery of two interactions with companion dwarf galaxies that