HD 43197 b is an extrasolar planet which orbits the G-type main sequence or subgiant star HD 43197, located approximately 204 light years away in the constellation Canis Major. This planet has a minimum mass 55% that of Jupiter and takes 0.85 years to orbit the star at a semimajor axis of 0.882 AU.[2] Its has a high eccentricity of 0.74, but its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.

HD 43197 b / Equiano
Discovery
Discovered byNaef et al.
Discovery siteLa Silla Observatory
Discovery dateOctober 19, 2009
radial velocity (HARPS)
Orbital characteristics[1]
0.882+0.035
−0.039
 AU
Eccentricity0.742+0.017
−0.018
308.9+2.3
−2.8
 d
2452535.102+17.503
−14.898
268.525°+3.824°
−4.523°
Semi-amplitude25.439+1.472
−1.121
 m/s
StarHD 43197
Physical characteristics[1]
Mass≥0.553+0.052
−0.048

In 2022, a second super-Jovian planet was discovered orbiting HD 43197 using a combination of radial velocity and astrometry. Assuming HD 43197 b shares the outer planet's orbital inclination, its true mass would be about 4 MJ.[1]

The planet HD 43197 b is named Equiano. The name was selected in the NameExoWorlds campaign by Nigeria, during the 100th anniversary of the IAU. Olaudah Equiano was a writer and abolitionist from Ihiala, Nigeria who fought injustice and for the elimination of the slave trade.[3][4]

References edit

  1. ^ a b c Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.
  2. ^ Naef, Dominique; Mayor, Michel; Lo Curto, Gaspare; Bouchy, François; Lovis, Christophe; Moutou, Claire; Benz, Willy; Pepe, Francesco; Queloz, Didier; Santos, Nuno C.; Ségransan, Damien; Udry, Stéphane; Bonfils, Xavier; Delfosse, Xavier; Forveille, Thierry; Hébrard, Guillaume; Mordasini, Christoph; Perrier, Christian; Boisse, Isabelle; Sosnowska, Danuta (2010). "The HARPS Search for Southern Extrasolar Planets XXIII. 8 Planetary Companions to Low-activity Solar-type Stars". Astronomy and Astrophysics. 523: A15. arXiv:1008.4600. Bibcode:2010A&A...523A..15N. doi:10.1051/0004-6361/200913616. S2CID 118845989.
  3. ^ "Approved names". NameExoworlds. Retrieved 2020-01-02.
  4. ^ "International Astronomical Union | IAU". www.iau.org. Retrieved 2020-01-02.