Unexpected stellar velocity distribution in the warped Galactic disk

  title={Unexpected stellar velocity distribution in the warped Galactic disk},
  author={R. L. Smart and Ronald Drimmel and Mario Gilberto Lattanzi and James Binney},
It is now over 40 years since radio observations of neutral hydrogen revealed the gaseous disk of our Galaxy to be warped. Subsequently, the warp has been detected in the distribution of Galactic dust, molecular clouds, and luminous stars,. Roughly half of all spiral galaxies have similarly warped disks, which suggests that warps are a common and long-lived phenomenon. However, there is still no consensus as to what induces galactic disks to become warped: intergalactic winds, tidal… 
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