Final Stages of Planet Formation

  title={Final Stages of Planet Formation},
  author={Peter Goldreich and Yoram Lithwick and Re’em Sari},
  journal={The Astrophysical Journal},
We address three questions regarding solar system planets: What determined their number? Why are their orbits nearly circular and coplanar? How long did they take to form? Runaway accretion in a disk of small bodies resulted in a tiny fraction of the bodies growing much larger than all the others. These big bodies dominated the viscous stirring of all bodies. Dynamical friction by small bodies cooled the random velocities of the big ones. Random velocities of small bodies were cooled by… Expand
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Terrestrial planet formation in extra-solar planetary systems
  • S. Raymond
  • Physics
  • Proceedings of the International Astronomical Union
  • 2007
Abstract Terrestrial planets form in a series of dynamical steps from the solid component of circumstellar disks. First, km-sized planetesimals form likely via a combination of sticky collisions,Expand


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