A possible correlation between planetary radius and orbital period for small planets

Ravit Helled, Michael Lozovsky, Shay Zucker

Research output: Contribution to journalArticlepeer-review


We suggest the existence of a correlation between the planetary radius and orbital period for planets with radii smaller than 4 R⊕. Using the Kepler data, we find a correlation coefficient of 0.5120, and suggest that the correlation is not caused solely by survey incompleteness. While the correlation coefficient could change depending on the statistical analysis, the statistical significance of the correlation is robust. Further analysis shows that the correlation originates from two contributing factors. One seems to be a power-law dependence between the two quantities for intermediate periods (3-100 d), and the other is a dearth of planets with radii larger than 2 R⊕ in short periods. This correlation may provide important constraints for small-planet formation theories and for understanding the dynamical evolution of planetary systems.

Original languageEnglish
Pages (from-to)L96-L98
JournalMonthly Notices of the Royal Astronomical Society: Letters
Issue number1
StatePublished - 2016


  • planets and satellites: detection
  • planets and satellites: dynamical evolution and stability
  • planets and satellites: formation
  • planets and satellites: fundamental parameters


Dive into the research topics of 'A possible correlation between planetary radius and orbital period for small planets'. Together they form a unique fingerprint.

Cite this