Epsilon Ceti, Latinized from ε Ceti, is the Bayer designation for a binary star system located in the equatorial constellation of Cetus. It is faintly visible to the naked eye with an apparent visual magnitude of +4.84.[2] Based upon an annual parallax shift of 14.58 mas,[1] it is located around 98 light-years away from the Sun.

This is a line-width spectroscopic binary star system. It has an orbital period of 2.65 years and an eccentricity of 0.23. The semimajor axis is 0.11 AU, or 11% of the distance between the Sun and the Earth, and the orbital plane is inclined at an angle of 24.2°.The primary member, component A, is an F-type main-sequence star with a stellar classification of F2 V. The spectrum of the secondary, component B, can not be readily separated from that of the primary, so its type can only be estimated as a main-sequence star lying in the range between F7 V and G4 V.[3] The system is estimated to be 1.8 billion years old,[5] with the primary having 1.4 times the mass of the Sun and the secondary being about equal to the Sun's mass.[3]

Name

This star, along with π Cet, ρ Cet and σ Cet, was Al Sufi's Al Sadr al Ḳaiṭos, the Whale's Breast.[7]

According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Sadr al Ḳaiṭos were the title for four stars: ρ Cet as Al Sadr al Ḳaiṭos I, σ Cet as Al Sadr al Ḳaiṭos II, this star (ε Cet) as Al Sadr al Ḳaiṭos III and π Cet as Al Sadr al Ḳaiṭos IV.[8]

In Chinese, 芻蒿 (Chú Hāo), meaning Hay, refers to an asterism consisting of ε Ceti, ρ Ceti, 77 Ceti, 67 Ceti, 71 Ceti and HD 14691.[9] Consequently, the Chinese name for ε Ceti itself is 芻蒿六 (Chú Hāo liù, English: the Sixth Star of Celestial Meadows).[10]

References