2011 HM102
Discovery[1][2] | |
---|---|
Discovered by | New Horizons KBO Search |
Discovery site | Las Campanas Obs. |
Discovery date | 29 April 2011 (first observed only) |
Designations | |
2011 HM102 | |
Orbital characteristics[1] | |
Epoch4 September 2017 (JD2458000.5) | |
Uncertainty parameter6 | |
Observation arc | (354 days) |
Aphelion | 32.778AU |
Perihelion | 27.660 AU |
30.219 AU | |
Eccentricity | 0.0847 |
166.12yr(60,675 days) | |
33.571° | |
0° 0m21.24s/ day | |
Inclination | 29.348° |
100.97° | |
151.24° | |
Physical characteristics | |
Dimensions | 100 km(est. at0.10)[4] |
8.1[1] | |
2011 HM102is the ninthNeptune trojandiscovered. It was first observed on 29 April 2011, during theNew Horizons KBO Search(268) using theMagellan II (Clay) TelescopeatLas Campanas Observatoryin Chile.[2][5]It has the same orbital period asNeptuneand orbits at theL5Lagrangian pointabout 60°backwards of Neptune.[3]
Orbit and classification[edit]
Neptune trojans areresonant trans-Neptunian objects(TNO) in a1:1mean-motionorbital resonancewith Neptune. These Trojans have asemi-major axis(a) very similar Neptune's (30.10 AU).
2011 HM102orbits the Sun with a semi-major axis of 30.219AUat a distance of 27.7–32.8 AU once every 166 years and 1 month (60,675 days). Its orbit has aneccentricityof 0.08 and aninclinationof 29°with respect to theecliptic.[1]Among the first 17 Neptune trojans discovered so far, it is the one with the highest inclination.[3]
Physical properties[edit]
Diameter and albedo[edit]
Based on a generic magnitude-to-diameter conversion, it measures approximately 100 kilometers in diameter using anabsolute magnitudeof 8.1 and an assumedalbedoof 0.10.[4]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).[3][4]
Surface[edit]
Observations withNIRSpecshowed that the spectrum of 2011 HM102does not exhibit clearTriton-likeice tholinfeatures. The surface is likely covered in a thin layer ofwater iceandCO2ice.Due to the variable color classification of this object, it is suspected that inhomogeneities in the surface composition exist.[6]
Numbering and naming[edit]
Due to itsorbital uncertainty,thisminor planethas not been numbered and its officialdiscoverershave not been determined.[1][2]If named, it will follow the naming scheme already established with385571 Otrera,which is to name these objects after figures related to theAmazons,an all-female warrior tribe that fought in theTrojan Waron the side of the Trojans against the Greek.[7]
Exploration[edit]
In October 2012,2011 HM102was the closest known object of any kind to theNew Horizonsspacecraft.[8]In mid- to late 2013,New Horizonspassed within 1.2 AU of2011 HM102,where it would be detectable with one of the onboard instruments.[5]An observation fromNew Horizonswould measure thephase curveof2011 HM102at phase angles unobtainable fromEarth.TheNew Horizonsteam eventually decided that they would not target2011 HM102for observations because the preparations for the Pluto approach took precedence.[9]
See also[edit]
References[edit]
- ^abcdef"JPL Small-Body Database Browser: (2011 HM102)"(2012-04-17 last obs.).Jet Propulsion Laboratory.Retrieved4 August2017.
- ^abcd"2011 HM102".Minor Planet Center.Retrieved4 August2017.
- ^abcd"List Of Neptune Trojans".Minor Planet Center.10 July 2017.Retrieved4 August2017.
- ^abc"Asteroid Size Estimator".CNEOS/JPL.Retrieved4 August2017.
- ^abParker, Alex H.; Buie, Marc W.; Osip, David J.; Gwyn, Stephen D. J.; Holman, Matthew J.; Borncamp, David M.; et al. (April 2013)."2011 HM102: Discovery of a High-inclination L5 Neptune Trojan in the Search for a Post-Pluto New Horizons Target".The Astronomical Journal.145(4): 96, 6 pp.arXiv:1210.4549v2.Bibcode:2013AJ....145...96P.doi:10.1088/0004-6256/145/4/96.S2CID119267735.Retrieved4 August2017.
- ^Markwardt, Larissa; Holler, Bryan J.; Lin, Hsing Wen; Gerdes, David W.; Adams, Fred C.; Malhotra, Renu; Napier, Kevin J. (6 October 2023). "First Near-IR Spectroscopic Survey of Neptune Trojans with JWST: Distinct Surface Compositions of Red vs Ultra-Red Neptune Trojans".arXiv:2310.03998[astro-ph.EP].
- ^Ticha, J.; et al. (10 April 2018)."DIVISION F / Working Group for Small Body Nomenclature Working Group for Small Body Nomenclature. THE TRIENNIAL REPORT (2015 Sept 1 - 2018 Feb 15)"(PDF).IAU.Retrieved25 August2018.
- ^Alex Parker (9 October 2012)."Citizen" Ice Hunters "help find a Neptune Trojan target for New Horizons".The Planetary Society.Retrieved4 August2017.
- ^Alex Parker (30 April 2013)."2011 HM102: A new companion for Neptune".The Planetary Society.Retrieved4 August2017.
External links[edit]
- A. Parker –2011 HM102:A new companion for Neptune – TPS
- MPEC 2012-T05:2011 HM102
- YouTube video showing the orbital evolution
- Discoverer comments
- AstDyS-2about2011 HM102
- 2011 HM102atAstDyS-2, Asteroids—Dynamic Site
- 2011 HM102at theJPL Small-Body Database