Neptune trojan

Neptune's L4 trojans with plutinos for reference.
  Neptune trojans (selection)
  · 2001 QR322
  · 2005 TN53
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Types of distant minor planets

Neptune trojans are bodies that orbit the Sun near one of the stable Lagrangian points of Neptune, similar to the trojans of other planets. They therefore have approximately the same orbital period as Neptune and follow roughly the same orbital path. Thirty-one Neptune trojans are currently known, of which 27 orbit near the Sun–Neptune L4 Lagrangian point 60° ahead of Neptune[1] and four orbit near Neptune's L5 region 60° behind Neptune.[1] The Neptune trojans are termed 'trojans' by analogy with the Jupiter trojans.

The discovery of 2005 TN53 in a high-inclination (>25°) orbit was significant, because it suggested a "thick" cloud of trojans[2] (Jupiter trojans have inclinations up to 40°[3]), which is indicative of freeze-in capture instead of in situ or collisional formation.[2] It is suspected that large (radius ≈ 100 km) Neptune trojans could outnumber Jupiter trojans by an order of magnitude.[4][5]

In 2010, the discovery of the first known L5 Neptune trojan, 2008 LC18, was announced.[6] Neptune's trailing L5 region is currently very difficult to observe because it is along the line of sight to the center of the Milky Way, an area of the sky crowded with stars.

  1. ^ a b Cite error: The named reference mpctrojans was invoked but never defined (see the help page).
  2. ^ a b Sheppard, Scott S.; Trujillo, Chadwick A. (June 2006). "A Thick Cloud of Neptune Trojans and Their Colors" (PDF). Science. 313 (5786): 511–514. Bibcode:2006Sci...313..511S. doi:10.1126/science.1127173. PMID 16778021. S2CID 35721399. Archived (PDF) from the original on 2010-07-16. Retrieved 2008-02-26.
  3. ^ Jewitt, David C.; Trujillo, Chadwick A.; Luu, Jane X. (2000). "Population and size distribution of small Jovian Trojan asteroids". The Astronomical Journal. 120 (2): 1140–7. arXiv:astro-ph/0004117. Bibcode:2000AJ....120.1140J. doi:10.1086/301453. S2CID 119450236.
  4. ^ E. I. Chiang and Y. Lithwick Neptune Trojans as a Testbed for Planet Formation, The Astrophysical Journal, 628, pp. 520–532 Preprint
  5. ^ David Powell (30 January 2007). "Neptune May Have Thousands of Escorts". Space.com. Archived from the original on 15 August 2008. Retrieved 2007-03-08.
  6. ^ Scott S. Sheppard (2010-08-12). "Trojan Asteroid Found in Neptune's Trailing Gravitational Stability Zone". Carnegie Institution of Washington. Archived from the original on 2010-08-15. Retrieved 2007-12-28.