The hidden giant: discovery of an enormous Galactic dwarf satellite in Gaia DR2

@article{Torrealba2019TheHG,
  title={The hidden giant: discovery of an enormous Galactic dwarf satellite in Gaia DR2},
  author={G. Torrealba and Vasily A Belokurov and Sergey E. Koposov and T. S. Li and Matthew G. Walker and Jason L. Sanders and Alex Geringer-Sameth and Daniel B. Zucker and Kyler W. Kuehn and N. Wyn Evans and Walter Dehnen},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2019}
}
We report the discovery of a Milky Way satellite in the constellation of Antlia. The Antlia 2 dwarf galaxy is located behind the Galactic disc at a latitude of b ∼ 11° and spans 1.26°, which corresponds to ∼2.9 kpc at its distance of 130 kpc. While similar in spatial extent to the Large Magellanic Cloud, Antlia 2 is orders of magnitude fainter at MV = −9 mag, making it by far the lowest surface brightness system known (at ∼31.9 mag arcsec−2), ∼100 times more diffuse than the so-called ultra… 

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