2011 HM102

Neptune trojan February 2018 yes 2011 HM 102 #C2E0FF 2011HM102 20190626 w84 i.png 2011 HM 102 as seen by the CTIO 4m Blanco Telescope 29 April 2011(first observed only) New Horizons KBO Search Las Campanas Obs. 2011 HM 102 Neptune trojan TNO distant 9 June 2026 (JD 2461200.5) 3 13.19 yr (4817 d) 32.3979 AU 27.6739 AU 30.0359 AU 0.07864 164.615 yr (60,126 d) 53.3142° 0.0059 ms / day 29.4240° 101.052° 151.019° 100 km (est. at 0.10) 8.1 2011 HM 102 is the ninth Neptune trojan discovered. It was first observed on 29 April 2011, during the New Horizons KBO Search 268 using the Magellan II (Clay) Telescope at Las Campanas Observatory in Chile. It has the same orbital period as Neptune and orbits at the Lagrangian point about 60° backwards of Neptune. Orbit and classification Neptune trojans are resonant trans-Neptunian objects (TNO) in a 1:1 mean-motion orbital resonance with Neptune. These trojans have a semi-major axis (a) very similar to Neptune's (30.10 AU). 2011 HM 102 orbits the Sun with a semi-major axis of 30.219 AU at a distance of 27.7–32.8 AU once every 166 years and 1 month (60,675 days). Its orbit has an eccentricity of 0.08 and an inclination of 29° with respect to the ecliptic. Among the first 17 Neptune trojans discovered so far, it is the one with the highest inclination. Physical properties Diameter and albedo Based on a generic magnitude-to-diameter conversion, it measures approximately 100 kilometers in diameter using an absolute magnitude of 8.1 and an assumed albedo of 0.10. It is an averaged-sized body among the first 17 Neptune trojans discovered so far, which measure between 60 and 200 kilometers (for an absolute magnitude of 9.3–6.6 and an assumed albedo of 0.10). Surface Observations with NIRSpec showed that the spectrum of 2011 HM102 does not exhibit clear Triton-like ice tholin features. The surface is likely covered in a thin layer of water ice and CO2 ice. Due to the variable color classification of this object, it is suspected that inhomogeneities in the surface composition exist.Markwardt Larissa Holler Bryan J. Lin Hsing Wen Gerdes David W. Adams Fred C. Malhotra Renu Napier Kevin J. 6 Oct 2023 First Near-IR Spectroscopic Survey of Neptune Trojans with JWST: Distinct Surface Compositions of Red vs Ultra-Red Neptune Trojans astro-ph.EP 2310.03998 Numbering and naming Due to its orbital uncertainty, this minor planet has not been numbered and its official discoverers have not been determined. 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.https://www.iau.org/static/science/scientific_bodies/working_groups/97/wg-sbn-triennial-report-2015-2018.pdf DIVISION F / Working Group for Small Body Nomenclature Working Group for Small Body Nomenclature. THE TRIENNIAL REPORT (2015 Sept 1 - 2018 Feb 15) 10 April 2018 25 August 2018 IAU Ticha, J. etal 25 August 2018 https://web.archive.org/web/20180825143250/https://www.iau.org/static/science/scientific_bodies/working_groups/97/wg-sbn-triennial-report-2015-2018.pdf dead Exploration In October 2012, 2011 HM 102 was the closest known object of any kind to the New Horizons spacecraft. In mid- to late 2013, New Horizons passed within 1.2 AU of 2011 HM 102, where it would be detectable with one of the onboard instruments. An observation from New Horizons would measure the phase curve of 2011 HM 102 at phase angles unobtainable from Earth. The New Horizons team eventually decided that they would not target 2011 HM 102 for observations because the preparations for the Pluto approach took precedence. See also List of New Horizons topics References 30em 2012-04-17 last obs. JPL Small-Body Database Browser: (2011 HM102) http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3609595 Jet Propulsion Laboratory 4 August 2017 2011 HM102 Minor Planet Center http://www.minorplanetcenter.net/db_search/show_object?object_id=2011+HM102 4 August 2017 List Of Neptune Trojans Minor Planet Center 10 July 2017 http://www.minorplanetcenter.org/iau/lists/NeptuneTrojans.html 4 August 2017 Asteroid Size Estimator CNEOS/JPL https://cneos.jpl.nasa.gov/tools/ast_size_est.html 4 August 2017 6 Alex H. Parker Marc W. Buie David J. Osip Stephen D. J. Gwyn Matthew J. Holman David M. Borncamp John R. Spencer Susan D. Benecchi Richard P. Binzel Francesca E. DeMeo Sébastian Fabbro Cesar I. Fuentes Pamela L. Gay J. J. Kavelaars Brian A. McLeod Jean-Marc Petit Scott S. Sheppard S. Alan Stern David J. Tholen David E. Trilling Darin A. Ragozzine Lawrence H. Wasserman the Ice Hunters April 2013 2011 HM102: Discovery of a High-inclination L5 Neptune Trojan in the Search for a Post-Pluto New Horizons Target http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2013AJ....145...96P The Astronomical Journal 145 4 96, 6 pp 2013AJ....145...96P 10.1088/0004-6256/145/4/96 1210.4549v2 119267735 4 August 2017 Citizen "Ice Hunters" help find a Neptune Trojan target for New Horizons Alex Parker The Planetary Society 9 October 2012 http://www.planetary.org/blogs/guest-blogs/20121009-parker-neptune-trojan-ice-hunters.html 4 August 2017 2011 HM102: A new companion for Neptune Alex Parker The Planetary Society 30 April 2013 http://www.planetary.org/blogs/guest-blogs/2013/0430-2011hm102-new-neptune-companion.html 4 August 2017 External links A. Parker – 2011 HM 102: A new companion for Neptune – TPS MPEC 2012-T05 : 2011 HM 102 YouTube video showing the orbital evolution Discoverer comments AstDyS-2 about 2011 HM 102 2011HM102 3609595 # Category:Minor planet object articles (unnumbered) # 20110429