Ontheotherhand， inhisaccuratesemi-analyticalsecularperturbationtheory (Laskar1988)， Laskarfindsthatlargeandirregularvariationscanappearintheeccentricitiesandinclinationsoftheterrestrialplanets， especiallyofMercuryandMarsonatime-scaleofseveral109yr (Laskar1996).TheresultsofLaskar'ssecularperturbationtheoryshouldbeconfirmedandinvestigatedbyfullynumericalintegrations.
Inthispaperwepresentpreliminaryresultsofsixlong-termnumericalintegrationsonallnineplanetaryorbits， coveringaspanofseveral109yr， andoftwootherintegrationscoveringaspanof ± 5 × 1010yr.Thetotalelapsedtimeforallintegrationsismorethan5yr， -termintegrationsisthatSolarsystemplanetarymotionseemstobestableintermsoftheHillstabilitymentionedabove， atleastoveratime-spanof ± ， inournumericalintegrationsthesystemwasfarmorestablethanwhatisdefinedbytheHillstabilitycriterion: notonlydidnocloseencounterhappenduringtheintegrationperiod， butalsoalltheplanetaryorbitalelementshavebeenconfinedinanarrowregionbothintimeandfrequencydomain， -termnumericalintegrations， ， wehavepreparedawebpage (access )， whereweshowraworbitalelements， theirlow-passfilteredresults， variationofDelaunayelementsandangularmomentumdeficit， andresultsofoursimpletimeCfrequencyanalysisonallofourintegrations.
