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arXiv · 2108.08383

Compositional Diversity of Rocky Exoplanets

Keith Putirka·Caroline Dorn·Natalie Hinkel·Cayman Unterborn
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Abstract

Star compositions are essential for examining densities and compositional ranges of rocky exoplanets, testing their similarity to Earth. Stellar elemental abundances and planetary orbital data show that of the ~5000 known minerals, exoplanetary silicate mantles will contain mostly olivine, orthopyroxene, and clinopyroxene, $\pm$ quartz, and magnesiuwustite at the extremes; wholly exotic mineralogies are likely absent. Understanding these exotic geological systems requires a better marriage of geological insights to astronomical data. The study of exoplanets is like a mirror, reflecting our incomplete understanding of Earth and neighboring planets; new geological/planetary experiments, informed by exoplanet studies, are needed for effectual progress.

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Keith Putirka, Caroline Dorn, Natalie Hinkel, Cayman Unterborn. 2021-08-18. Compositional Diversity of Rocky Exoplanets. https://arxiv.org/abs/2108.08383

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