A pebble accretion model for the formation of the terrestrial planets in the solar system

Research output: Contribution to journalJournal articleResearchpeer-review

Pebbles of millimeter sizes are abundant in protoplanetary discs around young stars. Chondrules inside primitive meteorites-formed by melting of dust aggregate pebbles or in impacts between planetesimals-have similar sizes. The role of pebble accretion for terrestrial planet formation is nevertheless unclear. Here, we present a model where inward-drifting pebbles feed the growth of terrestrial planets. The masses and orbits of Venus, Earth, Theia (which later collided with Earth to form the Moon), and Mars are all consistent with pebble accretion onto proto-planets that formed around Mars' orbit and migrated to their final positions while growing. The isotopic compositions of Earth and Mars are matched qualitatively by accretion of two generations of pebbles, carrying distinct isotopic signatures. Last, we show that the water and carbon budget of Earth can be delivered by pebbles from the early generation before the gas envelope became hot enough to vaporize volatiles.

Original languageEnglish
Article number0444
JournalScience Advances
Volume7
Issue number8
Number of pages13
ISSN2375-2548
DOIs
Publication statusPublished - 17 Feb 2021

ID: 260357868