Iota Ceti (ι Cet, ι Ceti) is the Bayer designation for a star system in the equatorial constellation of Cetus. It has the traditional name Deneb Kaitos Shemali.[9] The name was from the Arabic word ذنب قيطس الشمالي - dhanab qayṭas al-shamālī, meaning the northern tail of the sea monster. it is visible to the naked eye with an apparent visual magnitude of 3.562.[2] Based upon an annual parallax shift of 11.88 mas,[1] it lies around 275 light years from the Sun.
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Cetus |
Right ascension | 00h 19m 25.67416s[1] |
Declination | −08° 49′ 26.1111″[1] |
Apparent magnitude (V) | 3.562[2] |
Characteristics | |
Spectral type | K1.5 III[3] or K1 II + (K)[4] |
U−B color index | +1.278[2] |
B−V color index | +1.212[2] |
Variable type | Suspected[5] |
Astrometry | |
Radial velocity (Rv) | +19.35±0.17[6] km/s |
Proper motion (μ) | RA: −15.15[1] mas/yr Dec.: −37.11[1] mas/yr |
Parallax (π) | 11.88 ± 0.18 mas[1] |
Distance | 275 ± 4 ly (84 ± 1 pc) |
Absolute magnitude (MV) | −1.2[7] |
Details[6] | |
Mass | 2.78[3] M☉ |
Radius | 34 R☉ |
Luminosity | 398 L☉ |
Surface gravity (log g) | 2.1 cgs |
Temperature | 4,446±18 K |
Metallicity [Fe/H] | −0.09 dex |
Rotational velocity (v sin i) | 0.4 km/s |
Age | 2.23[3] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
In Chinese, 天倉 (Tiān Cāng), meaning Square Celestial Granary, refers to an asterism consisting of ι Ceti, η Ceti, θ Ceti, ζ Ceti, τ Ceti and 57 Ceti.[10] Consequently, the Chinese name for ι Ceti itself is 天倉一 (Tiān Cāng yī, English: the First Star of Square Celestial Granary.)[11]
This is an MK-standard star with a stellar classification of K1.5 III,[12] indicating that it is an evolved K-type giant star. However, Houk and Swift (1999) list a classification of K1 II,[4] which would indicate this is a bright giant. It is a suspected variable with a visual amplitude of around 0.05 magnitude.[5] The star has about 2.8[3] times the mass of the Sun, 34 times the Sun's radius, and radiates 398 times the solar luminosity from its outer atmosphere at an effective temperature of 4,446 K.[6]
Iota Ceti forms a wide astrometric pair with a common proper motion companion,[13] a magnitude 10.40 star at an angular separation of 106.4 arcseconds along a position angle of 191° (as of 2014).[14] This companion may be a K-type star.[4]