High-Velocity Cloud Complex H: A Satellite of the Milky Way in a Retrograde Orbit?

  title={High-Velocity Cloud Complex H: A Satellite of the Milky Way in a Retrograde Orbit?},
  author={Felix J. Lockman},
  journal={The Astrophysical Journal},
  • F. Lockman
  • Published 21 May 2003
  • Physics
  • The Astrophysical Journal
Observations with the Green Bank Telescope of 21 cm H I emission from the high-velocity cloud complex H suggest that it is interacting with the Milky Way. A model in which the cloud is a satellite of the Galaxy in an inclined, retrograde circular orbit reproduces both the cloud's average velocity and its velocity gradient with latitude. The model places complex H at R = 33 ± 9 kpc from the Galactic center on a retrograde orbit inclined ≈45° to the Galactic plane. At this location, it has a mass… 

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