(612243) 2001 QR322

Neptune trojan February 2022 yes (612243) 2001 QR 322 #C2E0FF File:Орбита астероида 2001 QR322.png M. W. Buie (DES) Cerro Tololo Obs. 21 August 2001 (612243) 2001 QR 322 Neptune trojanTNOdistant 4 September 2017 (JD 2458000.5) 3 12.26 yr (4,479 days) 30.968 AU 29.262 AU 30.115 AU 0.0283 165.27 yr (60,363 days) 86.551° 0.0060 ms / day 1.3250° 151.75° 151.11° 132 km 0.058 22.5 8.12 (612243) 2001 QR 322 is a minor planet and the first Neptune trojan discovered, by American astronomer Marc Buie of the Deep Ecliptic Survey at Cerro Tololo Observatory in Chile on 21 August 2001. It orbits ahead of Neptune at its Lagrangian point and measures approximately 132 km mi off 2 us in diameter. Other Neptune trojans have been discovered since. A study by American astronomers Scott Sheppard and Chad Trujillo from the Carnegie Institution suggests that Neptune could possibly have twenty times more trojans than Jupiter. Orbit 2001 QR 322 orbits the Sun with a semi-major axis of 30.115 AU at a distance of 29.3–31.0 AU once every 165 years and 3 months (60,363 days). Its orbit has an eccentricity of 0.03 and an inclination of 1° with respect to the ecliptic. Dynamical stability Early studies of the dynamical stability of 2001 QR 322, which used a small number of test particles spread over the uncertainties of just a few orbital parameters that were derived from a limited observation arc, suggested that 2001 QR 322 is on a remarkably stable orbit, because most test particles remained on trojan orbits for 5 Gyr. Thereafter, the stability of Neptune trojans was simply assumed. A more recent study, which used a very large number of test particles spread over the 3σ uncertainties in all six orbital parameters derived from a longer observational arc, has indicated that 2001 QR 322 is far less dynamically stable than previously thought. The test particles were lost exponentially with a half life of 553 Myr. Further observations can determine whether 2001 QR 322's orbit is actually within the dynamically stable or within the unstable part. The stability is strongly dependent on semi-major axis, with a≥30.30 AU being far less stable, but only very weakly dependent on the other orbital parameters. This is because those with larger semi-major axes have larger libration amplitudes, with amplitudes ~70° and above being destabilized by secondary resonances between the trojan motion and the dynamics of at least Saturn, Uranus, and Neptune. Secular resonances were found not to contribute to the dynamical stability of 2001 QR 322. Numbering and naming This minor planet was numbered and its discoverer determined by the Minor Planet Center on 28 March 2022 (M.P.C. 139893). If named, it will follow the naming scheme already established with 385571 Otrera, which is to name these objects after figures related to the Amazons, an all-female warrior tribe that fought in the Trojan War on the side of the Trojans against the Greek. Physical characteristics The discoverers estimate that the body has a mean diameter of 132 kilometers with a low albedo of 0.058 at an absolute magnitude of 8.12. It has a visual magnitude of 22.5. References 30em 2013-11-25 last obs. JPL Small-Body Database Browser: (2001 QR322) http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3092453 https://web.archive.org/web/20200901181006/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3092453 dead 1 September 2020 Jet Propulsion Laboratory 5 August 2017 (612243) 2001 QR322 Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=612243 8 April 2022 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 8 April 2022 Rules and Guidelines for naming non-cometary small Solar-System bodies – v1.0 Working Group Small Body Nomenclature PDF 20 December 2021 https://www.wgsbn-iau.org/documentation/NamesAndCitations.pdf#page=8 List of Neptune Trojans Minor Planet Center 10 July 2017 http://www.minorplanetcenter.org/iau/lists/NeptuneTrojans.html 4 August 2017 J. Horner P. S. Lykawka June 2010 2001 QR322: a dynamically unstable Neptune Trojan? Monthly Notices of the Royal Astronomical Society 405 1 49–56 2010MNRAS.405...49H 10.1111/j.1365-2966.2010.16441.x free 1002.4699 119241123 2008-07-21 using 26 of 26 observations Orbit Fit and Astrometric record for 01QR322 Marc W. Buie SwRI (Space Science Department) http://www.boulder.swri.edu/~buie/kbo/astrom/01QR322.html 2009-09-03 Neptune May Have Thousands of Escorts Space.com 30 January 2007 http://www.space.com/scienceastronomy/070130_st_neptune_trojans.html 2009-09-04 Lakdawalla Emily 2008 LC15, the first Trojan asteroid discovered in Neptune's L5 point 13 August 2010 The Planetary Society http://www.planetary.org/blogs/emily-lakdawalla/2010/2623.html 8 April 2022 List of Known Trans-Neptunian Objects Johnston's Archive 2 January 2022 Johnston Wm. Robert http://www.johnstonsarchive.net/astro/tnoslist.html External links 2001QR322 612243 (612243) 2001 QR 322 612243 612243 20010821