近日，法国巴黎城市大学Sébastien Charnoz团队报道了第一批太阳系固体的非平衡凝结。相关论文于2026年4月22日发表在《自然》杂志上。

原始陨石（球粒陨石）由太阳星云形成过程中处于非平衡态组合的矿物组成。由于其在前行星盘或小行星母体中经历了后续改造，其前体物质的形成条件仍不清楚。球粒陨石分为三大类：顽火辉石球粒陨石、普通球粒陨石和碳质球粒陨石，它们具有不同的总体成分和氧化状态。尽管平衡凝结模型解释了其中某些难熔组分的成分，但未能解释这三种矿物学类别的成因。此外，形成中的原行星盘内压力低、温度梯度陡峭、动力学输运时间尺度短，这些因素很可能阻碍了平衡过程。

研究组检验了以下假说：球粒陨石的前体是通过动力学非平衡凝结形成的。利用一个新的时间依赖凝结模型，研究组发现改变冷却速率和压力仅能产生三种矿物学类型。偏离平衡会导致矿物学向更氧化和含水的方向演化。将预测结果投影到尤里-克雷格图上时，这些矿物学类型的氧化还原状态接近顽火辉石球粒陨石、普通球粒陨石和碳质球粒陨石。这些结果表明，球粒陨石的矿物学多样性可能在部分程度上反映了局部的凝结动力学，这为氧化条件的大范围变化假说提供了一种替代解释。

附：英文原文

Title: Non-equilibrium condensation of the first Solar System solids

Author: Charnoz, Sbastien, Alon, Jrme, Chaussidon, Marc, Sossi, Paolo A., Marrocchi, Yves, Franco, Patrick

Issue&Volume: 2026-04-22

Abstract: Primitive meteorites (chondrites) consist of an out-of-equilibrium assemblage of minerals formed during the assembly of our solar nebula1. The conditions under which their precursors condensed remain unclear as a result of subsequent reprocessing in the protoplanetary disk or in asteroidal parent bodies. Chondrites are classified into three main classes—enstatite, ordinary and carbonaceous—and these are distinguished by different bulk composition and oxidation state2. Although equilibrium condensation models explain the composition of some of their refractory components3,4, they do not explain the emergence of three mineralogical classes. Moreover, the low pressures, steep temperature gradients and short dynamical transport timescales in forming protoplanetary discs probably hindered equilibrium. Here we test the hypothesis that chondrite precursors formed via kinetic non-equilibrium condensation. Using a new time-dependent condensation model, we show that varying the cooling rate and pressure produce only three types of mineralogies. Departure from equilibrium yields increasingly oxidized and hydrous mineralogies. When projected into a Urey–Craig diagram, the predicted mineralogical types fall close to the redox states of enstatite, ordinary and carbonaceous chondrites. These results suggest that the mineralogical diversity of chondrites may reflect, in part, local condensation kinetics, offering an alternative to large-scale variations of oxidation conditions.

DOI: 10.1038/s41586-026-10257-5

Source: https://www.nature.com/articles/s41586-026-10257-5