Does the Evolution of Complex Life Depend on the Stellar Spectral Energy Distribution?

  title={Does the Evolution of Complex Life Depend on the Stellar Spectral Energy Distribution?},
  author={Jacob D. Haqq-Misra},
  • J. Haqq-Misra
  • Published 17 May 2019
  • Physics, Chemistry, Medicine
  • Astrobiology
This article presents the proportional evolutionary time (PET) hypothesis, which posits that the mean time required for the evolution of complex life is a function of stellar mass. The "biological available window" is defined as the region of a stellar spectrum between 200 and 1200 nm that generates free energy for life. Over the ∼4 Gyr history of Earth, the total energy incident at the top of the atmosphere and within the biological available window is ∼1034 J. The hypothesis assumes that the… Expand
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