A CHEMICAL KINETICS NETWORK FOR LIGHTNING AND LIFE IN PLANETARY ATMOSPHERES

Journal Article · Sun May 01 00:00:00 EDT 2016 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.3847/0067-0049/224/1/9· OSTI ID:22661076

Rimmer, P. B.; Helling, Ch ^[1]

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1. School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS (United Kingdom)

There are many open questions about prebiotic chemistry in both planetary and exoplanetary environments. The increasing number of known exoplanets and other ultra-cool, substellar objects has propelled the desire to detect life and prebiotic chemistry outside the solar system. We present an ion–neutral chemical network constructed from scratch, Stand2015, that treats hydrogen, nitrogen, carbon, and oxygen chemistry accurately within a temperature range between 100 and 30,000 K. Formation pathways for glycine and other organic molecules are included. The network is complete up to H6C2N2O3. Stand2015 is successfully tested against atmospheric chemistry models for HD 209458b, Jupiter, and the present-day Earth using a simple one-dimensional photochemistry/diffusion code. Our results for the early Earth agree with those of Kasting for CO{sub 2}, H{sub 2}, CO, and O{sub 2}, but do not agree for water and atomic oxygen. We use the network to simulate an experiment where varied chemical initial conditions are irradiated by UV light. The result from our simulation is that more glycine is produced when more ammonia and methane is present. Very little glycine is produced in the absence of any molecular nitrogen and oxygen. This suggests that the production of glycine is inhibited if a gas is too strongly reducing. Possible applications and limitations of the chemical kinetics network are also discussed.

• OSTI ID: 22661076
• Journal Information: Astrophysical Journal, Supplement Series, Vol. 224, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
AMMONIA
ATMOSPHERIC CHEMISTRY
CARBON
CARBON DIOXIDE
CARBON MONOXIDE
DIFFUSION
ENVIRONMENT
GLYCINE
HYDROGEN
IRRADIATION
JUPITER PLANET
METHANE
NITROGEN
OXYGEN
PHOTOCHEMISTRY
PLANETARY ATMOSPHERES
SOLAR SYSTEM
ULTRAVIOLET RADIATION