Toward Planetesimals: Dense Chondrule Clumps in the Protoplanetary Nebula

  title={Toward Planetesimals: Dense Chondrule Clumps in the Protoplanetary Nebula},
  author={Jeffrey N. Cuzzi and Robert C. Hogan and Karim Shariff},
  journal={The Astrophysical Journal},
  pages={1432 - 1447}
We outline a scenario that traces a direct path from freely floating nebula particles to the first 10-100 km sized bodies in the terrestrial planet region, producing planetesimals that have properties matching those of primitive meteorite parent bodies. We call this “primary accretion.” The scenario draws on elements of previous work and introduces a new critical threshold for planetesimal formation. We presume the nebula to be weakly turbulent, which leads to dense concentrations of… 

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