论文标题
在后期的行星轰炸中充实木星的气氛
Enrichment of Jupiter's atmosphere by late planetesimal bombardment
论文作者
论文摘要
与原始极性相比，木星的大气富含大约3倍。这种富集的起源及其是否代表行星包络的大量组成仍然未知。木星的内部结构模型表明，其包膜与深内部分开，并且行星没有完全混合。这意味着木星的气氛在其形成结束之前充满了沉重的元素。这种富集可能是地球后期积聚的结果。但是，原位木星形成模型表明，随着行星质量的增加，积聚率下降，这无法解释木星的大气富集。在这项研究中，我们对木星的形成进行了建模，并表明原始jupiter从$ \ sim $ 20 au迁移到当前的位置可能会导致后期的地球增生和大气富集。如果原始jupiter仅迁移几个AU，则不会发生晚期的积聚。我们建议，如果木星的最外层完全混合并且相对较薄（最多$ \ sim $ 20 \％的质量），那么这种晚期积聚可以解释其测得的大气组成。因此，木星有可能经历了明显的轨道迁移，然后进行了晚期的积聚。
Jupiter's atmosphere is enriched with heavy elements by a factor of about 3 compared to proto-solar. The origin of this enrichment and whether it represent the bulk composition of the planetary envelope remain unknown. Internal structure models of Jupiter suggest that its envelope is separated from the deep interior and that the planet is not fully mixed. This implies that Jupiter's atmosphere was enriched with heavy elements just before the end of its formation. Such enrichment can be a result of late planetesimal accretion. However, in-situ Jupiter formation models suggest the decreasing accretion rate with increasing planetary mass, which cannot explain Jupiter's atmospheric enrichment. In this study, we model Jupiter's formation and show that an migration of proto-Jupiter from $\sim$ 20 AU to its current location can lead to a late planetesimal accretion and atmospheric enrichment. Late planetesimal accretion does not occur if proto-Jupiter migrates only a few AU. We suggest that if Jupiter's outermost layer is fully-mixed and is relatively thin (up to $\sim$ 20\% of its mass), such late accretion can explain its measured atmospheric composition. It is therefore possible that Jupiter underwent significant orbital migration followed by late planetesimal accretion.
