The Demographics of Long-Period Comets

@article{Francis2005TheDO,
  title={The Demographics of Long-Period Comets},
  author={Paul J. Francis},
  journal={The Astrophysical Journal},
  year={2005},
  volume={635},
  pages={1348-1361}
}
  • P. Francis
  • Published 5 September 2005
  • Physics
  • The Astrophysical Journal
The absolute magnitude and perihelion distributions of long-period comets are derived, using data from the Lincoln Near-Earth Asteroid Research (LINEAR) survey. The results are surprising in three ways. Firstly, the flux of comets through the inner solar system is much lower than some previous estimates. Secondly, the expected rise in comet numbers to larger perihelia is not seen. Thirdly, the number of comets per unit absolute magnitude does not significantly rise to fainter magnitudes. These… 
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A numerical simulation of the Oort cloud is used to explain the observed orbital distributions and numbers of Jupiter-family and Halley-type shortperiod comets. Comets are given initial orbits with
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