Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan
Hosting a ∼1.5 bar N2 atmosphere and reducing atmospheric composition, Titan has the energy sources needed to drive disequilibrium chemistry and hosts an aerosol layer which shields the surface from incident UV radiation. This world draws parallels to an early Earth-like world (although ∼200 K coole...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-09-01
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| Series: | Frontiers in Astronomy and Space Sciences |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fspas.2022.823227/full |
| _version_ | 1828378007465623552 |
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| author | Danica Adams Yangcheng Luo Yuk L. Yung Yuk L. Yung |
| author_facet | Danica Adams Yangcheng Luo Yuk L. Yung Yuk L. Yung |
| author_sort | Danica Adams |
| collection | DOAJ |
| description | Hosting a ∼1.5 bar N2 atmosphere and reducing atmospheric composition, Titan has the energy sources needed to drive disequilibrium chemistry and hosts an aerosol layer which shields the surface from incident UV radiation. This world draws parallels to an early Earth-like world (although ∼200 K cooler), and the atmospheric chemistry may be capable of forming relevant prebiotic species. Exo-Titan worlds at close-in orbits host photochemistry relevant to habitability with rich hydrocarbon chemistry. We investigate the effect of stellar type of the host star, equilibrium temperature, incident radiation, and vertical transport efficiency on the production of higher-order hydrocarbons. We find a greater incident radiation (a closer orbit) increases the rate of methane photolysis as well as photolysis of hydrocarbons. A larger H2 abundance and warmer temperature increases the rate of the back reaction H2 + CH3 → CH4 + H, and the temperature dependence is so great that CH3 recycles back into CH4 instead of forming C2H6. A larger H2 abundance and warmer temperature also encourages interesting cycling between C2H2, C2H3, and C2H4via reactions with atomic H. |
| first_indexed | 2024-04-14T08:19:30Z |
| format | Article |
| id | doaj.art-b27c96e0df93498698ed853897b0c21c |
| institution | Directory Open Access Journal |
| issn | 2296-987X |
| language | English |
| last_indexed | 2024-04-14T08:19:30Z |
| publishDate | 2022-09-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Astronomy and Space Sciences |
| spelling | doaj.art-b27c96e0df93498698ed853897b0c21c2022-12-22T02:04:16ZengFrontiers Media S.A.Frontiers in Astronomy and Space Sciences2296-987X2022-09-01910.3389/fspas.2022.823227823227Hydrocarbon chemistry in the atmosphere of a Warmer Exo-TitanDanica Adams0Yangcheng Luo1Yuk L. Yung2Yuk L. Yung3Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United StatesDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United StatesDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United StatesJet Propulsion Laboratory, La Cañada Flintridge, CA, United StatesHosting a ∼1.5 bar N2 atmosphere and reducing atmospheric composition, Titan has the energy sources needed to drive disequilibrium chemistry and hosts an aerosol layer which shields the surface from incident UV radiation. This world draws parallels to an early Earth-like world (although ∼200 K cooler), and the atmospheric chemistry may be capable of forming relevant prebiotic species. Exo-Titan worlds at close-in orbits host photochemistry relevant to habitability with rich hydrocarbon chemistry. We investigate the effect of stellar type of the host star, equilibrium temperature, incident radiation, and vertical transport efficiency on the production of higher-order hydrocarbons. We find a greater incident radiation (a closer orbit) increases the rate of methane photolysis as well as photolysis of hydrocarbons. A larger H2 abundance and warmer temperature increases the rate of the back reaction H2 + CH3 → CH4 + H, and the temperature dependence is so great that CH3 recycles back into CH4 instead of forming C2H6. A larger H2 abundance and warmer temperature also encourages interesting cycling between C2H2, C2H3, and C2H4via reactions with atomic H.https://www.frontiersin.org/articles/10.3389/fspas.2022.823227/fullhydrocarbonexoplanet atmospheretitanphotochemistryexoplanet astronomy |
| spellingShingle | Danica Adams Yangcheng Luo Yuk L. Yung Yuk L. Yung Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan Frontiers in Astronomy and Space Sciences hydrocarbon exoplanet atmosphere titan photochemistry exoplanet astronomy |
| title | Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan |
| title_full | Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan |
| title_fullStr | Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan |
| title_full_unstemmed | Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan |
| title_short | Hydrocarbon chemistry in the atmosphere of a Warmer Exo-Titan |
| title_sort | hydrocarbon chemistry in the atmosphere of a warmer exo titan |
| topic | hydrocarbon exoplanet atmosphere titan photochemistry exoplanet astronomy |
| url | https://www.frontiersin.org/articles/10.3389/fspas.2022.823227/full |
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