Details

Autor(en) / Beteiligte

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

Titel

A 1.9 EARTH RADIUS ROCKY PLANET AND THE DISCOVERY OF A NON-TRANSITING PLANET IN THE KEPLER-20 SYSTEM

Ist Teil von

• The Astronomical journal, 2016-12, Vol.152 (6), p.160

Ort / Verlag

United States

Erscheinungsjahr

2016

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• ABSTRACT Kepler-20 is a solar-type star ( V = 12.5) hosting a compact system of five transiting planets, all packed within the orbital distance of Mercury in our own solar system. A transition from rocky to gaseous planets with a planetary transition radius of ∼1.6 has recently been proposed by several articles in the literature. Kepler-20b (  ∼ 1.9 ) has a size beyond this transition radius; however, previous mass measurements were not sufficiently precise to allow definite conclusions to be drawn regarding its composition. We present new mass measurements of three of the planets in the Kepler-20 system that are facilitated by 104 radial velocity measurements from the HARPS-N spectrograph and 30 archival Keck/HIRES observations, as well as an updated photometric analysis of the Kepler data and an asteroseismic analysis of the host star (  =  and  =  ). Kepler-20b is a planet in a 3.7 day period with a mass of , resulting in a mean density of , indicating a rocky composition with an iron-to-silicate ratio consistent with that of the Earth. This makes Kepler-20b the most massive planet with a rocky composition found to date. Furthermore, we report the discovery of an additional non-transiting planet with a minimum mass of and an orbital period of ∼34 days in the gap between Kepler-20f ( P  ∼ 11 days) and Kepler-20d ( P  ∼ 78 days).