Importance of Biologically Active Aurora-like Ultraviolet Emission: Stochastic Irradiation of Earth and Mars by Flares and Explosions

  title={Importance of Biologically Active Aurora-like Ultraviolet Emission: Stochastic Irradiation of Earth and Mars by Flares and Explosions},
  author={David S. Smith and John Michael Scalo and J. Craig Wheeler},
  journal={Origins of life and evolution of the biosphere},
Habitable planets will be subject to intense sources of ionizing radiation and fast particles from a variety of sources - from the host star to distant explosions - on a variety of timescales. Monte Carlo calculations of high-energy irradiation suggest that the surfaces of terrestrial-like planets with thick atmospheres (column densities greater than about 100 g cm-2) are well protected from directly incident X-rays and γ-rays, but we find that sizeable fractions of incident ionizingradiation… 
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