Discovery of an unusual dwarf galaxy in the outskirts of the Milky Way

@article{Irwin2007DiscoveryOA,
  title={Discovery of an unusual dwarf galaxy in the outskirts of the Milky Way},
  author={Michael J. Irwin and Vasily A Belokurov and N. Wyn Evans and Emma V. Ryan-Weber and Jelte T.A. de Jong and Sergey E. Koposov and Daniel B. Zucker and Simon T. Hodgkin and Gerry F. Gilmore and Paresh Prema and Leslie Hebb and Ayesha Begum and Michael Fellhauer and Paul C. Hewett and Robert C. Kennicutt and Jr. and Mark I. Wilkinson and Daniel M. Bramich and Simon Vidrih and Hans-Walter Rix and Timothy C. Beers and John C. Barentine and Howard J. Brewington and Michael Harvanek and Jurek Krzesinski and Daniel C. Long and Atsuko Nitta and S. A. Snedden Cambridge and Mpia and Stephen K. Andrews and Msu and Apo and Cracow and Gemini},
  journal={The Astrophysical Journal},
  year={2007},
  volume={656}
}
We announce the discovery of a new dwarf galaxy, Leo T, in the Local Group. It was found as a stellar overdensity in the Sloan Digital Sky Survey Data Release 5 (SDSS DR5). The color-magnitude diagram of Leo T shows two well-defined features, which we interpret as a red giant branch and a sequence of young, massive stars. As judged from fits to the color-magnitude diagram, it lies at a distance of ~420 kpc and has an intermediate-age stellar population with a metallicity of [Fe/H] = -1.6… Expand

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