DeLuca, M. orcid.org/0000-0003-3207-6555, Sternovsky, Z. orcid.org/0000-0002-9658-1350, Armes, S.P. orcid.org/0000-0002-8289-6351 et al. (6 more authors) (2022) Differential ablation of organic coatings from micrometeoroids simulated in the laboratory. Journal of Geophysical Research: Planets, 127 (4). e2021JE007168. ISSN 2169-9097
Abstract
Micrometeoroids contain organic material that may undergo differential ablation during atmospheric entry, potentially depositing organic material into Earth's atmosphere and affecting the radar detectability of meteors. To investigate the differential ablation of organics, we used a dust accelerator to shoot submicron polypyrrole-coated olivine particles at speeds of 10–20 km/s into a gas target containing air. A set of biased electrodes placed along the path of the particles measured the charges generated when the particles ablated and the ablated molecules collided with gas molecules. We observed that the particles differentially ablate their organic polypyrrole coatings prior to their inorganic olivine cores, producing spikes in charge production, with charge yields of 104–105 C/kg even at relatively low speeds. These measurements suggest that large organic molecules survived ablation and are responsible for the observed charge production since small molecules either do not produce ions at those speeds or produce them in much lower quantities than observed. We modeled the ablation using basic meteor physics by assuming that the polypyrrole coating decomposes into pyrrole monomer. Extending these results to the ablation of micrometeoroids in the atmosphere indicates that organic coatings should ablate at high altitudes within relatively narrow altitude ranges, which has consequences for the detectability of meteors by radar. Since the ablated coatings generate relatively large molecules, the results also suggest that micrometeoroids can deliver complex organic material into planetary atmospheres by ablating them during entry, potentially serving as a source of prebiotic organics.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2022. American Geophysical Union. Reproduced in accordance with the publisher's self-archiving policy. |
Keywords: | micrometeoroids; ablation; organic materials; experimental studies |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > Department of Chemistry (Sheffield) |
Funding Information: | Funder Grant number ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL EP/R003009/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 07 Feb 2023 12:28 |
Last Modified: | 07 Feb 2023 22:09 |
Status: | Published |
Publisher: | American Geophysical Union (AGU) |
Refereed: | Yes |
Identification Number: | 10.1029/2021je007168 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:196078 |