Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 +/- 0.054 Earth-radii and a mass of 0.546 +/- 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 +/- 2.165 grams per cubic centimeter-close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 +/- 5%, similar to that of Mercury's interior.

GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star

Gandolfi, Davide;Barragán, Oscar;Goffo, Elisa;Serrano, Luisa M;
2021-01-01

Abstract

Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 +/- 0.054 Earth-radii and a mass of 0.546 +/- 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 +/- 2.165 grams per cubic centimeter-close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 +/- 5%, similar to that of Mercury's interior.
2021
374
6572
1271
1275
https://www.science.org/doi/10.1126/science.aay3253
Lam, Kristine W F; Csizmadia, Szilárd; Astudillo-Defru, Nicola; Bonfils, Xavier; Gandolfi, Davide; Padovan, Sebastiano; Esposito, Massimiliano; Hellier, Coel; Hirano, Teruyuki; Livingston, John; Murgas, Felipe; Smith, Alexis M S; Collins, Karen A; Mathur, Savita; Garcia, Rafael A; Howell, Steve B; Santos, Nuno C; Dai, Fei; Ricker, George R; Vanderspek, Roland; Latham, David W; Seager, Sara; Winn, Joshua N; Jenkins, Jon M; Albrecht, Simon; Almenara, Jose M; Artigau, Etienne; Barragán, Oscar; Bouchy, François; Cabrera, Juan; Charbonneau, David; Chaturvedi, Priyanka; Chaushev, Alexander; Christiansen, Jessie L; Cochran, William D; De Meideiros, José R; Delfosse, Xavier; Díaz, Rodrigo F; Doyon, René; Eigmüller, Philipp; Figueira, Pedro; Forveille, Thierry; Fridlund, Malcolm; Gaisné, Guillaume; Goffo, Elisa; Georgieva, Iskra; Grziwa, Sascha; Guenther, Eike; Hatzes, Artie P; Johnson, Marshall C; Kabáth, Petr; Knudstrup, Emil; Korth, Judith; Lewin, Pablo; Lissauer, Jack J; Lovis, Christophe; Luque, Rafael; Melo, Claudio; Morgan, Edward H; Morris, Robert; Mayor, Michel; Narita, Norio; Osborne, Hannah L M; Palle, Enric; Pepe, Francesco; Persson, Carina M; Quinn, Samuel N; Rauer, Heike; Redfield, Seth; Schlieder, Joshua E; Ségransan, Damien; Serrano, Luisa M; Smith, Jeffrey C; Šubjak, Ján; Twicken, Joseph D; Udry, Stéphane; Van Eylen, Vincent; Vezie, Michael
File in questo prodotto:
File Dimensione Formato  
Lam_2021.pdf

Accesso aperto

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 4.38 MB
Formato Adobe PDF
4.38 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1948760
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 29
  • ???jsp.display-item.citation.isi??? 25
social impact