Coreless terrestrial exoplanets

Linda Elkins-Tanton, Sara Seager

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Differentiation in terrestrial planets is expected to include the formation of a metallic iron core. We predict the existence of terrestrial planets that have differentiated but have no metallic core, planets that are effectively a giant silicate mantle. We discuss two paths to forming a coreless terrestrial planet, whereby the oxidation state during planetary accretion and solidification will determine the size or existence of any metallic core. Under this hypothesis, any metallic iron in the bulk accreting material is oxidized by water, binding the iron in the form of iron oxide into the silicate minerals of the planetary mantle. The existence of such silicate planets has consequences for interpreting the compositions and interior density structures of exoplanets based on their mass and radius measurements.

Original languageEnglish (US)
Pages (from-to)628-635
Number of pages8
JournalAstrophysical Journal
Volume688
Issue number1
DOIs
StatePublished - Nov 20 2008
Externally publishedYes

Fingerprint

terrestrial planets
extrasolar planets
silicates
planet
iron
planets
planetary mantles
iron oxides
silicate
solidification
Earth mantle
mantle
minerals
silicate mineral
oxidation
radii
iron oxide
water
accretion

Keywords

  • Accretion
  • Accretion disks
  • Planets and satellites: formation
  • Solar system: formation

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Coreless terrestrial exoplanets. / Elkins-Tanton, Linda; Seager, Sara.

In: Astrophysical Journal, Vol. 688, No. 1, 20.11.2008, p. 628-635.

Research output: Contribution to journalArticle

Elkins-Tanton, Linda ; Seager, Sara. / Coreless terrestrial exoplanets. In: Astrophysical Journal. 2008 ; Vol. 688, No. 1. pp. 628-635.
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