The Smith Cloud: A High-Velocity Cloud Colliding with the Milky Way

@article{Lockman2008TheSC,
  title={The Smith Cloud: A High-Velocity Cloud Colliding with the Milky Way},
  author={Felix J. Lockman and Robert A. Benjamin and A. J. Heroux and Glen I. Langston},
  journal={The Astrophysical Journal Letters},
  year={2008},
  volume={679},
  pages={L21 - L24}
}
New 21 cm H I observations made with the Green Bank Telescope show that the high-velocity cloud known as the Smith Cloud has a striking cometary appearance and many indications of interaction with the Galactic interstellar medium. The velocities of interaction give a kinematic distance of 12.4 ± 1.3 kpc, consistent with the distance derived from other methods. The Cloud is >3 × 1 kpc in size, and its tip at (l, b) ≈ 39°, –13° is 7.6 kpc from the Galactic center and 2.9 kpc below the Galactic… 

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