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Formation of Super-Earths

  • Hilke E. Schlichting
Living reference work entry

Abstract

Super-Earths are the most abundant planets known to date and are characterized by having sizes between that of Earth and Neptune, typical orbital periods of less than 100 days, and gaseous envelopes that are often massive enough to significantly contribute to the planet’s overall radius. Furthermore, super-Earths regularly appear in tightly packed multiple-planet systems, but resonant configurations in such systems are rare. This chapter summarizes current super-Earth formation theories. It starts from the formation of rocky cores and subsequent accretion of gaseous envelopes. We follow the thermal evolution of newly formed super-Earths and discuss their atmospheric mass loss due to disk dispersal, photoevaporation, core-cooling, and collisions. We conclude with a comparison of observations and theoretical predictions, highlighting that even super-Earths that appear as barren rocky cores today likely formed with primordial hydrogen and helium envelopes and discuss some paths forward for the future.

Keywords

Planet formation Gas accretion Giant impacts Shocks Resonances Super-earth Mini-neptune Exoplanets Envelope evolution Atmospheric mass loss 

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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.University of CaliforniaLos AngelesUSA
  2. 2.Massachusetts Institute of TechnologyCambridgeUSA

Section editors and affiliations

  • Ralph Pudritz
    • 1
  1. 1.Origins InstituteMcMaster UniversityHamiltonCanada

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