Electrostatic activation of prebiotic chemistry in substellar atmospheres
Abstract
Charged dust grains in the atmospheres of exoplanets may play a key role in the formation of prebiotic molecules, necessary to the origin of life. Dust grains submerged in an atmospheric plasma become negatively charged and attract a flux of ions that are accelerated from the plasma. The energy of the ions upon reaching the grain surface may be sufficient to overcome the activation energy of particular chemical reactions that would be unattainable via ion and neutral bombardment from classical, thermal excitation. As a result, prebiotic molecules or their precursors could be synthesised on the surface of dust grains that form clouds in exoplanetary atmospheres. This paper investigates the energization of the plasma ions, and the dependence on the plasma electron temperature, in the atmospheres of substellar objects such as gas giant planets. Calculations show that modest electron temperatures of $\approx 1$ eV ($\approx 10^{4}$ K) are enough to accelerate ions to sufficient energies that exceed the activation energies required for the formation of formaldehyde, ammonia, hydrogen cyanide and the amino acid glycine.
Citation
Stark , C R , Helling , C , Diver , D A & Rimmer , P 2014 , ' Electrostatic activation of prebiotic chemistry in substellar atmospheres ' , International Journal of Astrobiology , vol. 13 , no. Special Issue 2 , pp. 165-172 . https://doi.org/10.1017/S1473550413000475
Publication
International Journal of Astrobiology
Status
Peer reviewed
ISSN
1473-5504Type
Journal article
Rights
This is the author's accepted version of this article. The published version copyright © Cambridge University Press 2014 is available from http://journals.cambridge.org
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