Effects of Mg/Si on Exoplanetary Refractory Oxygen Budget

By Keith Cowing
Press Release
April 28, 2016
Filed under
Effects of Mg/Si on Exoplanetary Refractory Oxygen Budget

Solar photospheric abundances of refractory elements mirror the Earth’s to within ~10 mol% when normalized to the dominant terrestrial planet-forming elements Mg, Si and Fe. This allows for the adoption of Solar composition as an order-of-magnitude proxy for Earth’s.

It is not known, however, the degree to which this mirroring of stellar and terrestrial planet abundances holds true for other star-planet systems without determination of the composition of initial planetesimals via condensation sequence calculations and post condensation processes. We present the open-source Arbitrary Composition Condensation Sequence calculator (ArCCoS) to assess how the elemental composition of a parent star affects that of the planet-building material, including the extent of oxidation within the planetesimals.

We demonstrate the utility of ArCCoS by showing how variations in stellar refractory elements Mg and Si affect the condensation of oxygen, which directly lead to the resulting core to silicate ratio in exoplanets. This, thereby, removes significant degeneracy in the interpretation of the structures of exoplanets as well as providing observational tests for the validity of this model.

Cayman T. Unterborn, Wendy R. Panero
(Submitted on 28 Apr 2016)

Comments: 9 Pages, 4 figures, 7 Tables
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1604.08309 [astro-ph.EP] (or arXiv:1604.08309v1 [astro-ph.EP] for this version)
Submission history
From: Cayman Unterborn
[v1] Thu, 28 Apr 2016 05:41:32 GMT (219kb)

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