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30942 Helicaon
30942 Helicaon /hɛlɪˈkeɪɒn/ is a Jupiter trojan from the Trojan camp, approximately 33 kilometers (21 miles) in diameter. It was discovered on 8 February 1994, by Belgian astronomer Eric Elst at ESO's La Silla Observatory in northern Chile.[1] The dark Jovian asteroid has a long rotation period of 44.8 hours.[6] It was named after the Trojan warrior Helicaon from Greek mythology.[1] Orbit and classificationAs all Jupiter trojan, Helicaon is in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's L5 Lagrangian point, 60° behind its orbit .[4] It is also a non-family asteroid of the Jovian background population.[5] It orbits the Sun at a distance of 4.8–5.5 AU once every 11 years and 10 months (4,314 days; semi-major axis of 5.19 AU). Its orbit has an eccentricity of 0.07 and an inclination of 23° with respect to the ecliptic.[3] The body's observation arc begins with its official discovery observation at La Silla in February 1994.[1] NamingThis minor planet was named from Greek mythology after the Trojan warrior Helicaon, son of Antenor and King Priam's daughter, Laodice.[1] The official naming citation was published by the Minor Planet Center on 26 July 2010 (M.P.C. 71349).[9] Physical characteristicsHelicaon is an assumed C-type asteroid, while most larger Jupiter trojans are D-types.[6] Rotation periodIn February 2015, a rotational lightcurve of Helicaon was obtained from photometric observations over at total of 12 nights of photometric observations by Robert Stephens at the Center for Solar System Studies in Landers, California. Lightcurve analysis gave a rotation period of 44.77±0.05 hours with a brightness amplitude of 0.18 magnitude (U=2).[8][a] While not being a slow rotator, Helicaon has a significantly longer period than most larger Jupiter trojans (see table below).[6] Diameter and albedoAccording to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Helicaon measures 32.54 kilometers in diameter and its surface has an albedo of 0.050,[7] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 30.59 kilometers based on an absolute magnitude of 11.3.[6]
100+ largest Jupiter trojans
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Index:
pl ar de en es fr it arz nl ja pt ceb sv uk vi war zh ru af ast az bg zh-min-nan bn be ca cs cy da et el eo eu fa gl ko hi hr id he ka la lv lt hu mk ms min no nn ce uz kk ro simple sk sl sr sh fi ta tt th tg azb tr ur zh-yue hy my ace als am an hyw ban bjn map-bms ba be-tarask bcl bpy bar bs br cv nv eml hif fo fy ga gd gu hak ha hsb io ig ilo ia ie os is jv kn ht ku ckb ky mrj lb lij li lmo mai mg ml zh-classical mr xmf mzn cdo mn nap new ne frr oc mhr or as pa pnb ps pms nds crh qu sa sah sco sq scn si sd szl su sw tl shn te bug vec vo wa wuu yi yo diq bat-smg zu lad kbd ang smn ab roa-rup frp arc gn av ay bh bi bo bxr cbk-zam co za dag ary se pdc dv dsb myv ext fur gv gag inh ki glk gan guw xal haw rw kbp pam csb kw km kv koi kg gom ks gcr lo lbe ltg lez nia ln jbo lg mt mi tw mwl mdf mnw nqo fj nah na nds-nl nrm nov om pi pag pap pfl pcd krc kaa ksh rm rue sm sat sc trv stq nso sn cu so srn kab roa-tara tet tpi to chr tum tk tyv udm ug vep fiu-vro vls wo xh zea ty ak bm ch ny ee ff got iu ik kl mad cr pih ami pwn pnt dz rmy rn sg st tn ss ti din chy ts kcg ve
