对火星轨道变化问题的最后解释
作者君在作品相关中其实已经解释过这个问题。
不过仍然有人质疑——“你说得太含糊了”,“火星轨道的变化比你想象要大得多!”
那好吧,既然作者君的简单解释不够有力,那咱们就看看严肃的东西,反正这本书写到现在,嚷嚷着本书bug一大堆,用初高中物理在书中挑刺的人也不少。
以下是文章内容:
long-teraryorbitsinoursolarsystem
abstract
,atleastinoursis,±5x–plutosystemhavebeenmaintainedoverthe1011-yrtime-span.
1introduction
thequestionofthestabilityofoursolarsystersystem.
admp;amp;boss1996;itoamp;amp;tanikawa1999).,about±,.ofcoursethisstatementcannotbesimplyappliedtosystemswithstableorbitalresonancessuchastheneptune–plutosystem.
inadditiontothevaguenessoftheconceptofstability,theplanetsinoursolarsystearysystesforaperiodcoveringseveral10gyrtothoroughlyunderstandthelong-teraryorbits,sincechaoticdynamicalsystemsarecharacterizedbytheirstrongdependenceoninitialconditions.
fros,whichcoveraspanof~,butitseesalsoreroscillations.
ontheotherhand,inhisaccurateses,especiallyofskar1996).theresultsoflaskarssecularperturbationtheoryshouldbeconfirmedandinvestigatedbyfullynumericalintegrations.
inthispaperwepresentpreliaryorbits,coveringaspanofseveral109yr,andoftwootherintegrationscoveringaspanof±5x,,atleastoveratiaryorbitaleleunayelermomentumdeficit,andresultsofoursimpletime–frequencyanalysisonallofourintegrations.
insection2webrieflyexplainourdynasthatspans±5x.
2descriptionofthenumericalintegrations
(本部分涉及比较复杂的积分计算,作者君就不贴上来了,贴上来了起点也不一定能成功显示。)
weutilizeasecond-orderwisdom–holmansymplecticmapasourmainintegrationmethodwithaspecialstart-upproceduretoreducethetruncationerrorofanglevariables,‘warmstart’.
thestepsizeforthenuparetheseintegrationssimplyintermsofstepsizes.
intheintegrationoftheouterfiveplanets,wefixedthestepsizeat400d.
weadoptgaussfandgfunctionsinthesymplecticmaptogetherwiththethird-orderhalleymethodsmethodis15,buttheyneverreachedthemaximuminanyofourintegrations.
theintervalofthedataoutputisdforthecalculationsofallnineplanets,andaboutdfortheintegrationoftheouterfiveplanets.
althoughnooutputfilteringwasdonewhenthenumericalintegrationswereinprocess,.
accordingtooneofthebasicpropertiesofsyrngulartiveerrorintotalenergybyaboutoneorderofmagnitudeormore.
relativenungularngularmomentum,respectively,.
notethatdifferentoperatingsysternungularmomentum,whichshouldberigorouslypreserveduptomachine-eprecision.
sincethesyparethetestintegrationwiththetedtothevalue~8700°,about25rotationsofearthafter5gyr,,thelongitudeerrorofplutocanbeestimatedas~12°.thisvalueforplutoismuchbetterthantheresultinkinoshitaamp;amp;nakaiwherethedifferenceisestimatedas~60°.
3numericalresults–
:noorbitalcrossingsnorcloseencountersbetweenanypairofplanetstookplace.
first,,orbitalpositionsoftheterrestrialplanetsdifferlittlebetweentheinitialandfinalpartofeachnuaryorbitalmotionremainnearlythesameastheyareatpresent.
verticalviewofthefourinnerplanetaryorbitstheinitialpartofn+1.thefinalpartofn+1.theinitialpartofn?1.thefinalpartofn?1.ineachpanel,x.
thevariationofeccentricitiesandorbitalinclinationsfortheinnerfourplanetsintheinitialandfinalpartoftheintegrationn+,thecharacterofthevariationofplanetaryorbitaleles;s,.
theorbitalsseeroverthistime-span.
–frequencymaps
althoughtheplanetaryrlyinthecaseofearth,canpotentiallyhaveasignificanteffectonitssurfaceclirinsolationvariation().
togiveanoverviewofthelong-teraryorbitalskarsfrequencyanalysis.
.
eachfragrgeoverlappingpart:forexample,whentheithdatabeginsfromt=tiandendsatt=ti+t,thenextdatasegmentrangesfromti+δt≤ti+δt+t,whereδt?+treachesthetotalintegrationlenh.
weapplyanffttoeachofthedatafragments,andobtainnfrequencydiagrams.
ineachfrequencydiagracedbyagrey-scalechart.
weperforcexisrepresentstheperiodoftheoscillationoforbitalelements.
wehaveadoptedanfftbecauseofitsoverwhelposedintofrequencyponentsisterriblyhuge.
atypicalexabyplanetandelementbyelement.
wecalculateverylong-periodicvariationandexchangeofplanetaryorbitalenergyandangularunayelementsl,g,=?,,suchasymptomofinstabilityisnotprominentinourlong-termintegrations.
,thetotalorbitalenergyandangularponent,g0,,.
cosandallnineplanets,itisapparentthattheasares::,,wecannotneglectthecontributionfros,aswewillseeinsubsequentsections.
+1andn?,,,wecanseethatarysubsystem.
itisnotclearatthearyorbitalenergy.hence,theeccentricitiesofvenusandearthcanbedisturbedeasilybyjupiterandsaturn,,–earthpair,whichresultsinanegativecorrelationintheexchangeoforbitalenergyinthepair.
asfortheouterjovianplanetarysubsysteparedwiththatofthevenus–earthpair.
5±5x1010-yrintegrationsofouterplanetaryorbits
sincethejovianplanetaryarys.,thetypicalfrequencyoftheorbitaloscillationofplutoandtheotherouterplanetsisalmostconstantduringtheseverylong-termintegrationperiods,whichisdemonstratedinthetime–frequencymapsonourwebpage.
inthesetwointegrations,therelativenungularmomentumwas~10?10.
–plutosystem
kinoshitaaaryorbitsover±x,,λdenotesthemeanlongitude,Ωisthelongitudeoftheascendingnodeand?.
rgumentθ1=3λp?2λn??plibratesaround180°withanamplitudeofabout80°andalibrationperiodofabout2x104yr.
theargumentofperihelionofplutowp=θ2=?p?Ωplibratesaround90°x.
thelongitudeofthenodeofplutoreferredtothelongitudeofthenodeofneptune,θ3=Ωp?Ωn,,,theinclinationofplutobecoeses90°.whenθ3becoeseses90°;aterconfirni,nobiliamp;amp;carpino.
anargumentθ4=?p??n+3libratesaround180°withalongperiod,~x108yr.
inournurgurduringthewholeintegrationperiod.however,thefourthresonanceappearstobedifferent:thecriticalargutionovera1010-yrtime-scaleshorterintegrationswerenotabletodisclose.
6discussion
whatkindofdynaarysystearysystearysubsystearyseparationsbythesaregreaterthan26rh,,,.
,thewideseparationandsrendersthedisturbanceineffective;thedegreeofdisturbancebyjovianplanetsiso.heighteningofeccentricity,forexampleo~,.
althoughournursystem,.
——以上文段引自ito,;tanikawa,,483–500
这只是作者君参考的一篇文章,关于太阳系的稳定性。
还有其他论文,不过也都是英文的,相关课题的中文文献很少,那些论文下载一篇要九美元(《nature》真是暴利),作者君写这篇文章的时候已经回家,不在检测中心,所以没有数据库的使用权,下不起,就不贴上来了。