Edinburgh Research Explorer

The Mass of Kepler-93b and The Composition of Terrestrial Planets

Research output: Contribution to journalArticle

  • Courtney D. Dressing
  • David Charbonneau
  • Xavier Dumusque
  • Sara Gettel
  • Francesco Pepe
  • Andrew Collier Cameron
  • David W. Latham
  • Emilio Molinari
  • Stéphane Udry
  • Laura Affer
  • Aldo S. Bonomo
  • Lars A. Buchhave
  • Rosario Cosentino
  • Pedro Figueira
  • Aldo F. M. Fiorenzano
  • Avet Harutyunyan
  • Raphaëlle D. Haywood
  • John Asher Johnson
  • Mercedes Lopez-Morales
  • Christophe Lovis
  • Luca Malavolta
  • Michel Mayor
  • Giusi Micela
  • Fatemeh Motalebi
  • Valerio Nascimbeni
  • David F. Phillips
  • Giampaolo Piotto
  • Don Pollacco
  • Didier Queloz
  • Dimitar Sasselov
  • Damien Ségransan
  • Alessandro Sozzetti
  • Andrew Szentgyorgyi
  • Chris Watson

Related Edinburgh Organisations

Open Access permissions

Open

Documents

  • Download as Adobe PDF

    Final published version, 558 KB, PDF-document

    Licence: Creative Commons: Attribution-NonCommercial-ShareAlike (CC BY-NC-SA)

http://arxiv.org/abs/1412.8687
http://adsabs.harvard.edu/abs/2015ApJ...800..135D
Original languageEnglish
Pages (from-to)135
JournalAstrophysical Journal
Volume800
Issue number2
DOIs
StatePublished - 1 Feb 2015

Abstract

Kepler-93b is a 1.478 ± 0.019 R ⊕ planet with a 4.7 day period around a bright (V = 10.2), astroseismically characterized host star with a mass of 0.911 ± 0.033 M ⊙ and a radius of 0.919 ± 0.011 R ⊙. Based on 86 radial velocity observations obtained with the HARPS-N spectrograph on the Telescopio Nazionale Galileo and 32 archival Keck/HIRES observations, we present a precise mass estimate of 4.02 ± 0.68 M ⊕. The corresponding high density of 6.88 ± 1.18 g cm-3 is consistent with a rocky composition of primarily iron and magnesium silicate. We compare Kepler-93b to other dense planets with well-constrained parameters and find that between 1 and 6 M ⊕, all dense planets including the Earth and Venus are well-described by the same fixed ratio of iron to magnesium silicate. There are as of yet no examples of such planets with masses >6 M ⊕. All known planets in this mass regime have lower densities requiring significant fractions of volatiles or H/He gas. We also constrain the mass and period of the outer companion in the Kepler-93 system from the long-term radial velocity trend and archival adaptive optics images. As the sample of dense planets with well-constrained masses and radii continues to grow, we will be able to test whether the fixed compositional model found for the seven dense planets considered in this paper extends to the full population of 1-6 M ⊕ planets. Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundación Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.

    Research areas

  • planetary systems, planets and satellites: composition, stars: individual: Kepler-93 &equals KOI 69 &equals KIC 3544595, techniques: radial velocities

Download statistics

No data available

ID: 19673928