107 Piscium is a single star in the constellation of Pisces. This star is faintly visible to the naked eye with an apparent visual magnitude that has been measured varying between 5.14 and 5.26. However, that finding of variation was not confirmed by subsequent observations and is most likely spurious data. It is located at a distance of about away from the Sun. 107 Piscium is drifting closer to the Sun with a radial velocity of −33.6, and is predicted to come as close as in around 135,800 years.
Nomenclature 107 Piscium is the star's Flamsteed designation. John Flamsteed numbered the stars of Pisces from 1 to 113, publishing his Catalogus Britannicus in 1725. He accidentally numbered 107 Piscium twice, as he also allocated it the designation of 2 Arietis.
In Chinese astronomy, this was historically identified as the determinative star of the asterism Yòu Gēng (, Official in Charge of Pasturing). Later versions of this asterism identified Rho Piscium as the first star.
Properties This object is a K-type main-sequence star with a stellar classification of K1V, indicating it is generating energy from core hydrogen fusion. It is somewhat older than the Sun—approximately 6 billion years old. The star has 86% of the mass, 80.8% of the radius of the Sun, shines with 44% of the Sun's luminosity and has an effective temperature of . It is rotating slowly with a period of . The abundance of elements other than hydrogen and helium—the star's metallicity—is slightly lower than that of the Sun. The level of chromospheric activity is similar to the Sun, and it shows a simple cycle of variation.
107 Piscium has been examined for the presence of an infrared excess caused by exozodiacal dust, but none was detected. The habitable zone for this star, defined as the locations where liquid water could be present on an Earth-like planet, is at a radius of 0.52– (AU), where is the average distance from the Earth to the Sun.
In 1997, based on data collected during the Hipparcos mission, the star was categorized as an astrometric binary with a period of . However, this result has not been confirmed.
See also Gliese 67 Gliese 69 List of nearest K-type stars
References NSV 600, database entry, New Catalogue of Suspected Variable Stars, the improved version, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 24, 2008.
HR 493, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 24, 2008.
Entry 01425+2016, The Washington Double Star Catalog , United States Naval Observatory. Accessed on line September 24, 2008.
HD 10476, database entry, The Geneva-Copenhagen Survey of Solar neighbourhood, J. Holmberg et al., 2007, CDS ID V/117A. Accessed on line November 19, 2008.
HD 10476, catalog entry, Fundamental parameters and elemental abundances of 160 F-G-K stars based on OAO spectrum database, Y. Takeda, CDS ID J/PASJ/59/335; see also Publications of the Astronomical Society of Japan 59, #2 (April 2007), pp. 335–356, .
External links SolStation article on 107 Piscium.