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.
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