首页 死在火星上

第76章 对火星轨道变化问题的最后解释


tem.thesecondfeature,whichwethinkismoreimportantforthelong-termstabilityofourplanetarysystem,isthedifferenceindynamicaldistancebetweenterrestrialandjovianplanetarysubsystems(itotanikawa1999,2001).whenwemeasureplanetaryseparationsbythemutualhillradii(r_),separationsamongterrestrialplanetsaregreaterthan26rh,whereasthoseamongjovianplanetsarelessthan14rh.thisdifferenceisdirectlyrelatedtothedifferencebetweendynamicalfeaturesofterrestrialandjovianplanets.terrestrialplanetshavesmallermasses,shorterorbitalperiodsandwiderdynamicalseparation.theyarestronglyperturbedbyjovianplanetsthathavelargermasses,longerorbitalperiodsandnarrowerdynamicalseparation.jovianplanetsarenotperturbedbyanyothermassivebodies.
  thepresentterrestrialplanetarysystemisstillbeingdisturbedbythemassivejovianplanets.however,thewideseparationandmutualinteractionamongtheterrestrialplanetsrendersthedisturbanceineffective;thedegreeofdisturbancebyjovianplanetsiso(ej)(orderofmagnitudeoftheeccentricityofjupiter),sincethedisturbancecausedbyjovianplanetsisaforcedoscillationhavinganamplitudeofo(ej).heighteningofeccentricity,forexampleo(ej)~0.05,isfarfromsufficienttoprovokeinstabilityintheterrestrialplanetshavingsuchawideseparationas26rh.thusweassumethatthepresentwidedynamicalseparationamongterrestrialplanets(;26rh)isprobablyoneofthemostsignificantconditionsformaintainingthestabilityoftheplanetarysystemovera109-yrtime-span.ourdetailedanalysisoftherelationshipbetweendynamicaldistancebetweenplanetsandtheinstabilitytime-scaleofsolarsystemplanetarymotionisnowon-going.
  althoughournumericalintegrationsspanthelifetimeofthesolarsystem,thenumberofintegrationsisfarfromsufficienttofilltheinitialphasespace.itisnecessarytoperformmoreandmorenumericalintegrationstoconfirmandexamineindetailthelong-termstabilityofourplanetarydynamics.
  ——以上文段引自ito,t.tanikawa,.336,483–500(2002)
  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。m.XiApe.cOm
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