Reduced Atmospheres of Post-Impact Worlds: Hiding Reducing Power in the Planet Core
Creators
- 1. Institute of Astronomy, University of Cambridge
- 2. Department of Earth Sciences, University of Cambridge
- 3. Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London
Description
Reduced surface environments are required for many prebiotic chemical pathways. Large impacts onto Hadean Earth have been suggested as scenarios able to generate such environments on a global scale. Physical and chemical processes that occur shortly after impact can, however, limit the reducing power that is available at planet surface. Here, we present impact simulations and chemical calculations that demonstrate the efficient loss of reducing power from the post-impact planetary surface. This loss occurs via the dynamic escape of impactor core material, or the sinking of this material to the planet core, during impact, and through interactions between the atmosphere and the impact-generated melt phase. We suggest that post-impact surface environments are sufficiently reduced that species important to prebiotic chemistry can form (e.g., HCN, HCCCN). Additionally, the formation of a reduced impact-generated melt phase allows for reducing power to be stored in the planet mantle, where it can degas to the surface on geologic timescales.
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ESA_poster_A0.pdf
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Additional details
Funding
- STFC Cambridge IoA 2019 DTP ST/T505985/1
- UK Research and Innovation
References
- Wünnemann, K., Collins, G. S., & Osinski, G. R. (2008). Numerical modelling of impact melt production in porous rocks. Earth and Planetary Science Letters, 269(3-4), 530-539.
- Bottke, W. F., Walker, R. J., Day, J. M., Nesvorny, D., & Elkins-Tanton, L. (2010). Stochastic late accretion to Earth, the Moon, and Mars. science, 330(6010), 1527-1530.
- Day, J. M., Brandon, A. D., & Walker, R. J. (2016). Highly siderophile elements in Earth, Mars, the Moon, and asteroids. Reviews in Mineralogy and Geochemistry, 81(1), 161-238.
- Genda, H., Brasser, R., & Mojzsis, S. J. (2017). The terrestrial late veneer from core disruption of a lunar-sized impactor. Earth and Planetary Science Letters, 480, 25-32.
- Marchi, S., Canup, R. M., & Walker, R. J. (2018). Heterogeneous delivery of silicate and metal to the Earth by large planetesimals. Nature geoscience, 11(1), 77-81.
- Benner, S. A., Bell, E. A., Biondi, E., Brasser, R., Carell, T., Kim, H. J., ... & Trail, D. (2020). When did life likely emerge on Earth in an RNA‐first process?. ChemSystemsChem, 2(2), e1900035.
- Zahnle, K. J., Lupu, R., Catling, D. C., & Wogan, N. (2020). Creation and evolution of impact-generated reduced atmospheres of early Earth. The Planetary Science Journal, 1(1), 11.
- Citron, R. I., & Stewart, S. T. (2022). Large impacts onto the early Earth: planetary sterilization and iron delivery. The Planetary Science Journal, 3(5), 116.
- Itcovitz, J. P., Rae, A. S., Citron, R. I., Stewart, S. T., Sinclair, C. A., Rimmer, P. B., & Shorttle, O. (2022). Reduced atmospheres of post-impact worlds: The early Earth. The Planetary Science Journal, 3(5), 115.