112 Piscium, also named Zibbatu, is a star away in the constellation Pisces. With an apparent magnitude of 5.9, it is faintly visible to the naked eye under good viewing conditions. It appears near the brighter star Alpha Piscium (Alrescha) in the sky; the two are about apart.
Nomenclature 112 Piscium is the star's Flamsteed designation; other designations include HD 12235 in the Henry Draper Catalogue. The Akkadian zibbātu "tails" is a Babylonian name for the constellation Pisces, which was originally visualized as the tails of a swallow (SIM.MAḪ). The IAU Working Group on Star Names adopted the name Zibbatu for 112 Piscium on 17 September 2026.
Properties The stellar classification of 112 Piscium is G2IV, indicating that it is a G-type subgiant star that has evolved off the main sequence. Other sources classify it as G0V, matching a main-sequence star. Gaia DR3 supports a subgiant classification. This star has about 1.1 times the mass and 1.8 times the radius of the Sun, and is radiating 3.7 times the Sun's luminosity from its photosphere at an effective temperature of . Classified as a population I star, it is older than the Sun and has a somewhat higher metallicity (abundance of elements heavier than helium). It is thought to be a member of the HR 1614 group of stars that share a common motion through space.
Planetary system Two planetary companions to this star (HD 12235) were detected in 2022 using both radial velocity and astrometry. A companion was previously suspected. The inner planet has a minimum mass of about 10 Earth masses, making it a sub-Neptune; it orbits close to its star with a period of just 4.4 days. The outer planet is a super-Jupiter about 10 times the mass of Jupiter; it has a wide orbit with a period of about 100 years.
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