Bollard Jean, Connelly James N, Whitehouse Martin J, Pringle Emily A, Bonal Lydie, Jørgensen Jes K, Nordlund Åke, Moynier Frédéric, Bizzarro Martin
Centre for Star and Planet Formation, University of Copenhagen, Copenhagen, Denmark.
Department of Geosciences, Swedish Museum of Natural History, Stockholm, Sweden.
Sci Adv. 2017 Aug 9;3(8):e1700407. doi: 10.1126/sciadv.1700407. eCollection 2017 Aug.
The most abundant components of primitive meteorites (chondrites) are millimeter-sized glassy spherical chondrules formed by transient melting events in the solar protoplanetary disk. Using Pb-Pb dates of 22 individual chondrules, we show that primary production of chondrules in the early solar system was restricted to the first million years after the formation of the Sun and that these existing chondrules were recycled for the remaining lifetime of the protoplanetary disk. This finding is consistent with a primary chondrule formation episode during the early high-mass accretion phase of the protoplanetary disk that transitions into a longer period of chondrule reworking. An abundance of chondrules at early times provides the precursor material required to drive the efficient and rapid formation of planetary objects via chondrule accretion.
原始陨石（球粒陨石）中最丰富的成分是毫米大小的玻璃质球形球粒，它们是由太阳原行星盘中的瞬态熔化事件形成的。通过对22个单独球粒的铅-铅年代测定，我们发现太阳系早期球粒的主要生成过程仅限于太阳形成后的头一百万年，并且这些现存的球粒在原行星盘的剩余寿命中被反复利用。这一发现与原行星盘早期高质量吸积阶段的一次主要球粒形成事件相一致，该阶段随后转变为球粒再加工的较长时期。早期大量的球粒提供了通过球粒吸积驱动行星体高效快速形成所需的前体物质。
