Capturing the oxidation of silicon carbide in rocky exoplanetary interiors

Kaustubh Hakim, Wim Van Westrenen, Carsten Dominik

Research output: Contribution to JournalArticleAcademicpeer-review

Abstract

Context. Theoretical models predict the condensation of silicon carbide around host stars with C/O ratios higher than 0.65 (cf. C/OSun = 0.54), in addition to its observations in meteorites, interstellar medium and protoplanetary disks. Consequently, the interiors of rocky exoplanets born from carbon-enriched refractory material are often assumed to contain large amounts of silicon carbide. Aims. Here we aim to investigate the stability of silicon carbide in the interior of carbon-enriched rocky exoplanets and to derive the reaction leading to its transformation. Methods. We performed a high-pressure high-Temperature experiment to investigate the reaction between a silicon carbide layer and a layer representative of the bulk composition of a carbon-enriched rocky exoplanet. Results. We report the reaction leading to oxidation of silicon carbide producing quartz, graphite, and molten iron silicide. Combined with previous studies, we show that in order to stabilize silicon carbide, carbon saturation is not sufficient, and a complete reduction of Fe2+ to Fe0 in a planetary mantle is required, suggesting that future spectroscopic detection of Fe2+ or Fe3+ on the surface of rocky exoplanets would imply the absence of silicon carbide in their interiors.

Original languageEnglish
Article numberL6
Pages (from-to)1-5
Number of pages5
JournalAstronomy and Astrophysics
Volume618
Early online date22 Oct 2018
DOIs
Publication statusPublished - Oct 2018

Fingerprint

silicon carbides
silicon
oxidation
extrasolar planets
carbon
planetary mantles
refractory materials
protoplanetary disks
meteorites
graphite
meteorite
condensation
quartz
saturation
mantle
iron
stars
experiment

Keywords

  • Methods: laboratory: molecular
  • Planets and satellites: composition
  • Planets and satellites: interiors
  • Planets and satellites: surfaces
  • Planets and satellites: Terrestrial planets

Cite this

@article{e09ed5557b7144cc8e530228c241c04e,
title = "Capturing the oxidation of silicon carbide in rocky exoplanetary interiors",
abstract = "Context. Theoretical models predict the condensation of silicon carbide around host stars with C/O ratios higher than 0.65 (cf. C/OSun = 0.54), in addition to its observations in meteorites, interstellar medium and protoplanetary disks. Consequently, the interiors of rocky exoplanets born from carbon-enriched refractory material are often assumed to contain large amounts of silicon carbide. Aims. Here we aim to investigate the stability of silicon carbide in the interior of carbon-enriched rocky exoplanets and to derive the reaction leading to its transformation. Methods. We performed a high-pressure high-Temperature experiment to investigate the reaction between a silicon carbide layer and a layer representative of the bulk composition of a carbon-enriched rocky exoplanet. Results. We report the reaction leading to oxidation of silicon carbide producing quartz, graphite, and molten iron silicide. Combined with previous studies, we show that in order to stabilize silicon carbide, carbon saturation is not sufficient, and a complete reduction of Fe2+ to Fe0 in a planetary mantle is required, suggesting that future spectroscopic detection of Fe2+ or Fe3+ on the surface of rocky exoplanets would imply the absence of silicon carbide in their interiors.",
keywords = "Methods: laboratory: molecular, Planets and satellites: composition, Planets and satellites: interiors, Planets and satellites: surfaces, Planets and satellites: Terrestrial planets",
author = "Kaustubh Hakim and {Van Westrenen}, Wim and Carsten Dominik",
year = "2018",
month = "10",
doi = "10.1051/0004-6361/201833942",
language = "English",
volume = "618",
pages = "1--5",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",

}

Capturing the oxidation of silicon carbide in rocky exoplanetary interiors. / Hakim, Kaustubh; Van Westrenen, Wim; Dominik, Carsten.

In: Astronomy and Astrophysics, Vol. 618, L6, 10.2018, p. 1-5.

Research output: Contribution to JournalArticleAcademicpeer-review

TY - JOUR

T1 - Capturing the oxidation of silicon carbide in rocky exoplanetary interiors

AU - Hakim, Kaustubh

AU - Van Westrenen, Wim

AU - Dominik, Carsten

PY - 2018/10

Y1 - 2018/10

N2 - Context. Theoretical models predict the condensation of silicon carbide around host stars with C/O ratios higher than 0.65 (cf. C/OSun = 0.54), in addition to its observations in meteorites, interstellar medium and protoplanetary disks. Consequently, the interiors of rocky exoplanets born from carbon-enriched refractory material are often assumed to contain large amounts of silicon carbide. Aims. Here we aim to investigate the stability of silicon carbide in the interior of carbon-enriched rocky exoplanets and to derive the reaction leading to its transformation. Methods. We performed a high-pressure high-Temperature experiment to investigate the reaction between a silicon carbide layer and a layer representative of the bulk composition of a carbon-enriched rocky exoplanet. Results. We report the reaction leading to oxidation of silicon carbide producing quartz, graphite, and molten iron silicide. Combined with previous studies, we show that in order to stabilize silicon carbide, carbon saturation is not sufficient, and a complete reduction of Fe2+ to Fe0 in a planetary mantle is required, suggesting that future spectroscopic detection of Fe2+ or Fe3+ on the surface of rocky exoplanets would imply the absence of silicon carbide in their interiors.

AB - Context. Theoretical models predict the condensation of silicon carbide around host stars with C/O ratios higher than 0.65 (cf. C/OSun = 0.54), in addition to its observations in meteorites, interstellar medium and protoplanetary disks. Consequently, the interiors of rocky exoplanets born from carbon-enriched refractory material are often assumed to contain large amounts of silicon carbide. Aims. Here we aim to investigate the stability of silicon carbide in the interior of carbon-enriched rocky exoplanets and to derive the reaction leading to its transformation. Methods. We performed a high-pressure high-Temperature experiment to investigate the reaction between a silicon carbide layer and a layer representative of the bulk composition of a carbon-enriched rocky exoplanet. Results. We report the reaction leading to oxidation of silicon carbide producing quartz, graphite, and molten iron silicide. Combined with previous studies, we show that in order to stabilize silicon carbide, carbon saturation is not sufficient, and a complete reduction of Fe2+ to Fe0 in a planetary mantle is required, suggesting that future spectroscopic detection of Fe2+ or Fe3+ on the surface of rocky exoplanets would imply the absence of silicon carbide in their interiors.

KW - Methods: laboratory: molecular

KW - Planets and satellites: composition

KW - Planets and satellites: interiors

KW - Planets and satellites: surfaces

KW - Planets and satellites: Terrestrial planets

UR - http://www.scopus.com/inward/record.url?scp=85056490391&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85056490391&partnerID=8YFLogxK

U2 - 10.1051/0004-6361/201833942

DO - 10.1051/0004-6361/201833942

M3 - Article

VL - 618

SP - 1

EP - 5

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - L6

ER -