Challenges of identifying putative planetary-origin meteorites composed of non-igneous material

TL;DR

This paper reviews the challenges in identifying non-igneous, sedimentary-origin meteorites of planetary origin, emphasizing the importance of multiple evidence types beyond isotopic tests.

Contribution

It highlights the complexity of confirming extraterrestrial sedimentary meteorites and proposes a comprehensive approach considering various physical and chemical signatures.

Findings

Candidate parent bodies include Earth, Mars, Enceladus, Ganymede, Europa, and hypothetical planets.

Terrestrial contamination affects isotopic signatures, complicating origin identification.

Signs like hypervelocity impact, fusion crust, and shock features are key indicators of meteoritic origin.

Abstract

This concept article discusses the challenges of identifying planetary-origin meteorites of non-igneous composition, primarily of sedimentary origin, distinct from SNC meteorites. The paper reviews evidence on putative sedimentary-origin meteorites and potential parent bodies for sedimentary meteorites. Authors conclude that the list of candidate parent bodies for sedimentary meteorites includes, but is not limited by the Earth, Mars, Enceladus, Ganymede, Europa, and hypothetical planets that could exist between orbits of Mars and Jupiter in the past. Authors argue that extraterrestrial origin and a parent body for meteoritic sedimentary rocks may be identified based on the entire body of evidence which is not limited solely by tests of oxygen and noble gas isotopes whose signatures may undergo terrestrial contamination and may exhibit significant heterogeneity within the Solar system and within the parent cosmic bodies. Observed fall of a cosmic body, evidence of hypervelocity fall, signs of impact in target, and the presence of fusion crust, melting, and/or shock deformation features in the fragments should be considered as priority signs of meteoritic origin.