HD 28254
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HD 28254 is a binary star system located 180 light-years away in the constellation Dorado. The primary component is an 8th magnitude G-type main-sequence star. This star is larger, cooler, brighter, and more massive than the Sun, and its metal content is 2.3 times as much as the Sun. In 2009, a gas giant exoplanet was found in orbit around the star.
HD 28254 is a G-type star with a spectral type G1IV/V,[2] indicating that it has begun its evolution off the main sequence. It is estimated to have a mass 11% larger than the Sun's, a radius 57% larger, and an age around 7.8 billion years. It has a luminosity of 1.57 times the solar luminosity and an effective temperature of about 5,600 K.[4] HD 28254 has a low activity level and a larger metallicity than the Sun, with 2.3 times the solar iron abundance.[2]
HD 28254 is the brighter component of a visual binary. Its companion, HD 28254 B, has a visual apparent magnitude of 13.8 and is located at a separation of 4.3 arcseconds. The two stars have maintained the same separation through time, indicating that they form a physical binary system.[6] Furthermore, the radial velocity of the primary shows signs of orbital motion. From its brightness, the companion star is probably a red dwarf with spectral type between M0V and M2V, with about 48% the solar mass. The projected separation between the stars is 235 AU, corresponding to an orbital period of more than 1,000 years.[2]
