HD 158259 explained

HD 158259 is a main sequence star located 88lk=onNaNlk=on away in the constellation Draco. It hosts a system of at least five planets, discovered by the SOPHIE échelle spectrograph using the radial velocity method.

Characteristics

HD 158259 is a G0 star with a rotation period of days. More detailed analysis of the spectral assigns a class of G5V, but with the metal lines of an F9 star.

Planets

Five planets have been confirmed orbiting HD 158259, along with one unconfirmed planet. These planets were discovered by N.C. Hara et.al. by the radial velocity method, published in Astronomy & Astrophysics in April 2020.^[1] The innermost planet, HD 158259 b, was also observed to transit the star by TESS. The planets orbit in a nearly 3:2 orbital resonance, with the period ratios 1.5758, 1.5146, 1.5296, 1.5130, and 1.4480, respectively, starting from the innermost pairing. A dynamical analysis has shown that the system is stable. One of the planets, HD 158259 b, is a super-Earth; the rest, including the unconfirmed HD 158259 g, are mini-Neptunes.

See also

• List of exoplanets discovered in 2020 - HD 158259 b, c, d, e, and f

Notes and References

1. Hara . N. C. . Bouchy . F. . Stalport . M. . Boisse . I. . Rodrigues . J. . Delisle . J.-B. . Santerne . A. . Henry . G. W. . Arnold . L. . Astudillo-Defru . N. . Borgniet . S. . Bonfils . X. . Bourrier . V. . Brugger . B. . Courcol . B. . April 2020 . The SOPHIE search for northern extrasolar planets: XVI. HD 158259: A compact planetary system in a near-3:2 mean motion resonance chain . Astronomy & Astrophysics . 636 . L6 . 10.1051/0004-6361/201937254 . 0004-6361.