Epsilon Ceti is a binary star system located in the equatorial constellation of Cetus. Its name is a Bayer designation that is Latinized from õ Ceti and abbreviated Epsilon Cet or õ Cet. This system is faintly visible to the naked eye as a point of light with an apparent visual magnitude of +4.84. Based upon an annual parallax shift of , it is located around 79 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 , or 11% of the distance between the Sun and the Earth, and the orbital plane is inclined at an angle of 24.2ð to the plane of the sky.
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. The system is estimated to be 1.8 billion years old, with the primary having 1.4 times the mass of the Sun and the secondary being about equal to the Sun's mass.
This star, along with àCet, àCet and àCet, was Al Sufi's Al Sadr al Ḳaiá¹Âos, the Whale's Breast.
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Sadr al Ḳaiá¹Âos were the title for four stars: àCet as Al Sadr al Ḳaiá¹Âos I, àCet as Al Sadr al Ḳaiá¹Âos II, this star (õ Cet) as Al Sadr al Ḳaiá¹Âos III and àCet as Al Sadr al Ḳaiá¹Âos IV.
In Chinese, (), meaning Hay, refers to an asterism consisting of õ Ceti, àCeti, 77 Ceti, 67 Ceti, 71 Ceti and HD 14691. Consequently, the Chinese name for õ Ceti itself is (, ).