Burkhardt Christoph, Spitzer Fridolin, Morbidelli Alessandro, Budde Gerrit, Render Jan H, Kruijer Thomas S, Kleine Thorsten
Institut für Planetologie, University of Münster, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany.
Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d'Azur, Boulevard de l'Observatoire, 06304 Nice, Cedex 4, France.
Sci Adv. 2021 Dec 24;7(52):eabj7601. doi: 10.1126/sciadv.abj7601. Epub 2021 Dec 22.
Two fundamentally different processes of rocky planet formation exist, but it is unclear which one built the terrestrial planets of the solar system. They formed either by collisions among planetary embryos from the inner solar system or by accreting sunward-drifting millimeter-sized “pebbles” from the outer solar system. We show that the isotopic compositions of Earth and Mars are governed by two-component mixing among inner solar system materials, including material from the innermost disk unsampled by meteorites, whereas the contribution of outer solar system material is limited to a few percent by mass. This refutes a pebble accretion origin of the terrestrial planets but is consistent with collisional growth from inner solar system embryos. The low fraction of outer solar system material in Earth and Mars indicates the presence of a persistent dust-drift barrier in the disk, highlighting the specific pathway of rocky planet formation in the solar system.
岩石行星形成存在两种根本不同的过程，但尚不清楚是哪一种过程造就了太阳系的类地行星。它们要么是由内太阳系的行星胚胎相互碰撞形成，要么是通过吸积来自外太阳系向太阳方向漂移的毫米大小的“卵石”形成。我们表明，地球和火星的同位素组成受内太阳系物质（包括陨石未采样的最内盘物质）之间的两组分混合控制，而外太阳系物质的贡献按质量计仅限于百分之几。这反驳了类地行星的卵石吸积起源，但与内太阳系胚胎的碰撞生长相一致。地球和火星中外太阳系物质的低比例表明盘中存在持续的尘埃漂移屏障，突出了太阳系中岩石行星形成的特定途径。
Zotero 插件
