Long-Period Comets and the Oort Cloud

@article{Fernndez2000LongPeriodCA,
  title={Long-Period Comets and the Oort Cloud},
  author={Julio A. Fern{\'a}ndez},
  journal={Earth, Moon, and Planets},
  year={2000},
  volume={89},
  pages={325-343}
}
Long-period (LP) comets, Halley-type (HT) comets, and even some comets of the Jupiter family, probably come from the Oort cloud, a huge reservoir of icy bodies that surrounds the solar system. Therefore, these comets become important probes to learn about the distant Oort cloud population. We review the fundamental dynamical properties of LP comets, and what is our current understanding of the dynamical mechanisms that bring these bodies from the distant Oort cloud region to the inner planetary… 
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