Chiron-type comet

A Chiron-type comet (CTC) is a member of a small family of comets defined as having a semi-major axis larger than that of Jupiter (5.2 AU) and a Tisserand's parameter with respect to Jupiter (TJupiter) of more than 3.[1][2]

The family is named after its largest and most prominent member 2060 Chiron, officially designated as both a comet (95P/Chiron) and a minor planet of the centaur-class, which blurs the line between the two groups.

There are four numbered comets considered to be classical members of this family: 39P/Oterma, 165P/LINEAR, 166P/NEAT, and 167P/CINEOS.[2]

CTCs are distinct from the Encke-type comets (ETC) and Jupiter-family comets (JFC). Contrary to the Chiron-type comets, JFCs have a TJupiter of less than 3 (typically with a period of less than 20 years), while the ETCs have a semi-major axis smaller than that of Jupiter.[1] Another group, the Halley-type comets (HTC), only have a classical definition, that is a period between 20 and 200 years. Members of the CTC family have a dynamical lifetime of 6.5 million years, much longer than the 50,000 years attributed to the Jupiter-family comets.[3]

References

  1. ^ a b "NASA PDS: Small Bodies Node – Object Classifications". NASA PDS –Planetary Data System. Retrieved 18 July 2019.
  2. ^ a b "JPL Small-Body Database Browser – Orbit Classification – Chiron-type Comet". Jet Propulsion Laboratory. Retrieved 18 July 2019.
  3. ^ Tiscareno, Matthew S.; Malhotra, Renu (December 2003). "The Dynamics of Known Centaurs". The Astronomical Journal. 126 (6): 3122–3131. arXiv:astro-ph/0211076. Bibcode:2003AJ....126.3122T. doi:10.1086/379554. S2CID 8177784.