The HD 2638 members A and BC have a projected separation of about25.5±1.9 AU and thus an orbital period of around 130 years.[4] They have a combinedstellar classification of K1V.[3] The primary component is aG-type main-sequence star with a class of G8V.[4] It is smaller and less massive than the Sun, and has a lower luminosity.[6] The secondary is a binary consisting of twored dwarf stars on close orbit with combined mass less than half the mass of the primary, and a composite spectral class of M1V.[4]
^abHouk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars".Michigan Spectral Survey.5.Bibcode:1999MSS...C05....0H.
^abcRoberts Jr, Lewis C.; Tokovinin, Andrei; Mason, Brian D.; Riddle, Reed L.; Hartkopf, William I.; Law, Nicholas M.; Baranec, Christoph (2015), "Know the Star, Know the Planet. III. Discovery of Late-Type Companions to Two Exoplanet Host Stars",The Astronomical Journal,149 (4): 118,arXiv:1503.01211,Bibcode:2015AJ....149..118R,doi:10.1088/0004-6256/149/4/118,S2CID30908636
^Tsantaki, M.; Sousa, S. G.; Adibekyan, V. Zh.; Santos, N. C.; Mortier, A.; Israelian, G. (2013). "Deriving precise parameters for cool solar-type stars. Optimizing the iron line list".Astronomy and Astrophysics.555.arXiv:1304.6639.Bibcode:2013A&A...555A.150T.doi:10.1051/0004-6361/201321103.
