Assessing the solar radiation contribution to early atmospheric conditions for life
Abstract
Examination of the impact of energetic charged particle fluence on atmospheres of exoplanets orbiting Sun-like stars has suggested that persistent high-energy proton irradiation in the young Earth’s atmosphere may have produced some of the important building blocks for life. These protons were likely accelerated at the Sun in superflares and associated coronal mass ejections, many of which with energy content significantly greater than that of the Carrington event of 1859. Interactions of solar energetic particles with the early atmosphere could have resulted in higher populations of key molecules from which the requisite components for life were formed. As well as charged particles, superflares were also likely to produce high-energy gamma-rays and neutrons. Recently, dozens of solar flares have been identified with Fermi/LAT as sources of long-duration-gamma-ray-flare emission, high-energy penetrating emission that can last for many hours. Solar neutrons have also been associated with extreme solar flare events. Both of these could significantly affect the atmospheric chemistry of young Earth-sized exoplanets. Based on modern measurements, we have computed the total fluence and energy of gamma-rays, neutrons, and solar energetic particle (SEP) observations from PAMELA, one could expect from extreme events that would contribute to the production of basic life chemistry.
- Publication:
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Solar Heliospheric and INterplanetary Environment (SHINE 2019)
- Pub Date:
- May 2019
- Bibcode:
- 2019shin.confE.128M