terfiveplahefourjovianplaspluspluto).theresultsexhibittherigorousstabilityoftheouterplaarysystemoverthislongtime-span.orbitalfigurations(fig.12),andvariationofetricitiesandinations(fig.13)showthisveryloabilityoftheouterfiveplasinboththetimeandthefrequenains.althoughwedonotshoshere,thetypicalfrequencyoftheorbitaloscillationofplutoaherouterplasisalmoststantduringtheseverylong-termiionperiods,whichisdemonstratediime–frequencymapsonourwebpage.
iwoiions,therelativenumericalerrorialenergywas~10?6andthatofthetotalangularmomentumwas~10?10.
5.1resoheune–plutosystem
kinoshitanakai(1996)iedtheouterfiveplaaryorbitsover±5.5x109yr.theyfoundthatfourmajorresoweeuneandplutoaremaintainedduringthewholeiionperiod,andthattheresonancesmaybethemaincausesofthestabilityoftheorbitofpluto.themajorfourresonancesfoundinpreviousresearchareasfollows.inthefollowingdescriptioesthemeanlongitude,Ωisthelongitudeoftheasdingnodeand?isthelongitudeofperihelion.subscriptspaeplutoaune.
meanmotionresoweeuneandpluto(3:2).thecriticalargumentθ1=3λp?2λn??plibratesaround180°litudeofabout80°andalibrationperiodofabout2x104yr.
theargumentofperihelionofplutowp=θ2=?p?Ωplibratesaround90°eriodofabout3.8x106yr.thedominantperiodicvariationsoftheetricityandinationofplutoaresynizedwiththelibrationofitsargumentofperihelion.thisisanticipatedinthesecularperturbationtheorystructedbykozai(1962).
thelongitudeofthenodeofplutoreferredtothelongitudeofthenodeofune,θ3=Ωp?Ωn,circulatesandtheperiodofthiscirculationisequaltotheperiodofθ2libration.whenθ3beeszero,i.e.thelongitudesofasdingnodesofuneandplutooverlap,theinationofplutobeaximum,theetricitybeinimumandtheargumentofperihelionbees90°.whenθ3bees180°,theinationofplutobeinimum,theetricitybeaximumandtheargumentofperihelionbees90°again.williamsbenson(1971)anticipatedthistypeofresoerfirmedbymilani,nobilicarpino(1989).
anargumentθ4=?p??n 3(Ωp?Ωn)libratesaround180°withalongperiod,~5.7x108yr.
本章未完,点击下一页继续阅读