From Stars To Diverse Mantles, Melts, Crusts And Atmospheres Of Rocky Exoplanets

This review is focused on describing the logic by which we make predictions of exoplanetary compositions and mineralogies, and how these processes could lead to compositional diversity among rocky exoplanets.

We use these predictions to determine the sensitivity of present-day and future observations to detecting compositional differences between rocky exoplanets and the four terrestrial planets. First, we review data on stellar abundances and infer how changes in composition may manifest themselves in the expected bulk compositions of rocky exoplanets (section 2).

Converting this information in mass-radius relationships requires calculation of the stable mineral assemblages at a given temperature-pressure-composition (T-P-X), an exercise we describe in section 3. Should the planet be hot enough to engender partial melting of the mantle, then these liquids are likely to rise to the surface and erupt to form planetary crusts; the possible compositional and mineralogical variability of which we examine in section 4. Finally, the expected spectroscopic responses of such crusts are examined in section 5.

Claire Marie Guimond, Haiyang Wang, Fabian Seidler, Paolo Sossi, Aprajit Mahajan, Oliver Shorttle

Comments: Chapter 8 accepted for publication in the Reviews in Mineralogy and Geochemistry (RiMG) Volume 90 on “Exoplanets: Compositions, Mineralogy, and Evolution” edited by Natalie Hinkel, Keith Putirka, and Siyi Xu; 40 pages, 11 figures, and 3 equations
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR); Geophysics (physics.geo-ph)
Cite as: arXiv:2404.15427 [astro-ph.EP] (or arXiv:2404.15427v1 [astro-ph.EP] for this version)
Submission history
From: Oliver Shorttle [via Natalie Hinkel as proxy]
[v1] Tue, 23 Apr 2024 18:19:11 UTC (3,326 KB)
https://arxiv.org/abs/2404.15427
Astrobiology, Astrochemistry, Astrogeology,