Marchi Simone, Korenaga Jun
Southwest Research Institute, Boulder, CO, USA.
Yale University, New Haven, CT, USA.
Nature. 2025 May;641(8065):1111-1120. doi: 10.1038/s41586-025-08970-8. Epub 2025 May 28.
Terrestrial planets-Mercury, Venus, Earth and Mars-formed by the accretion of smaller objects. The Earth was probably the latest terrestrial planet to form and reached about 99% of its final mass within about 60-100 Myr after condensation of the first solids in the Solar System. This Review examines the disproportionate role of the last approximately 1% of planetary growth, or late accretion, in controlling the long-term evolution of the Earth and other terrestrial planets. Late accretion may have been responsible for shaping Earth's distinctive geophysical and chemical properties and generating pathways conducive to prebiotic chemistry. Differences in the late accretion of a planet may provide a rationale for interpreting the distinct properties of Venus and Earth (for example, tectonism, atmospheric composition, water content), the surface dichotomy of Mars and the high core-to-silicate mass ratio of Mercury. Large collisions and ensuing processes are likely to occur and modulate the evolution of rocky exoplanets as well, and they should be considered in our quest to find Earth-like worlds.
类地行星——水星、金星、地球和火星——是由较小天体的吸积作用形成的。地球可能是最晚形成的类地行星，在太阳系中第一批固体物质凝聚后的大约60 - 100百万年时间内，达到了其最终质量的约99%。本综述探讨了行星增长的最后约1%，即晚期吸积，在控制地球和其他类地行星长期演化过程中所起的不成比例的作用。晚期吸积可能塑造了地球独特的地球物理和化学性质，并产生了有利于前生物化学的途径。行星晚期吸积的差异可能为解释金星和地球的不同性质（例如构造活动、大气成分、含水量）、火星的表面二分性以及水星的高核与硅酸盐质量比提供了一个理由。大型碰撞及随后的过程很可能也会发生并调节岩石系外行星的演化，在我们寻找类地世界的过程中应该考虑这些因素。
