A Hypothesis for the Rapid Formation of Planets

  title={A Hypothesis for the Rapid Formation of Planets},
  author={Susanne Pfalzner and Michele T. Bannister},
  journal={The Astrophysical Journal Letters},
The discovery of 1I/‘Oumuamua confirmed that planetesimals must exist in great numbers in interstellar space. Originally generated during planet formation, they are scattered from their original systems and subsequently drift through interstellar space. As a consequence they should seed molecular clouds with at least hundred-meter-scale objects. We consider how the galactic background density of planetesimals, enriched from successive generations of star and system formation, can be… 

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