HD_19467_B
HD 19467
Star in the constellation Eridanus
HD 19467 is a star with an orbiting brown dwarf companion in the equatorial constellation of Eridanus. It has an apparent visual magnitude of 6.97,[1] which is a challenge to view with the naked eye. The system is located at a distance of 104.5 light years based on parallax measurements,[2] and is drifting further away with a radial velocity of 7 km/s.[5] It has a high proper motion, traversing the celestial sphere at an angular rate of 0.258 arcsec yr−1.[11] Based on the motion and chemical abundances of this star it has been considered a likely member of the Wolf 630 group of co-moving stars, although its age estimate is inconsistent with that assignment.[12]
The spectrum of HD 19467 presents as a G-type main-sequence star with a stellar classification of G3 V.[4] It has been identified as a solar twin based on the similarity of its physical properties to the Sun.[13] This is an older star,[6] with age estimates range from 5.4[3] up to 10.1 billion years,[8] depending on the study. It is considered a thin disk star, which should theoretically limit the age to no more than 8 billion years.[6] The spin rate is correspondingly low with a rotation period of 29.5 days.[6] Based on the abundance of iron, the metallicity is lower than solar.[14][6] The level of magnetic activity in the star's chromosphere as well as X-ray emission are at most below the equivalent level in the Sun.[3]