Xi2 Ceti

Xi² Ceti, Latinized from ξ² Ceti, is a star located in the equatorial constellation of Cetus. It is visible to the naked eye with an apparent visual magnitude of +4.3.^[2] This star is located at a distance of approximately 197 light years from the Sun based on parallax, and is drifting further away with a radial velocity of 12 km/s.^[6] It made its closest approach some 2.7 million years ago at a distance of around 128 light-years.^[5]

For other stars with this Bayer designation, see ξ Ceti.

Xi² Ceti

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Cetus
Right ascension	02h 28m 09.55706s[1]
Declination	+08° 27′ 36.2168″[1]
Apparent magnitude (V)	+4.279[2]
Characteristics
Spectral type	B9.5III[3] or A0III-[4]
U−B color index	−0.137[5]
B−V color index	−0.053±0.003[5]
Astrometry
Radial velocity (Rv)	11.90±1.3[6] km/s
Proper motion (μ)	RA: 23.707±0.844[1] mas/yr Dec.: −4.787±0.778[1] mas/yr
Parallax (π)	16.5681±0.4608 mas[1]
Distance	197 ± 5 ly (60 ± 2 pc)
Absolute magnitude (MV)	+0.45[5]
Details
Mass	2.45[7] M☉
Radius	2.60±0.17[8] R☉
Luminosity	80.13[5] L☉
Surface gravity (log g)	4.00±0.25[8] cgs
Temperature	10,630±400[9] K
Metallicity [Fe/H]	−0.43±0.04[5] dex
Rotational velocity (v sin i)	55[7] km/s
Age	127[7] Myr
Other designations
ξ2 Cet, 73 Ceti, BD+07°388, HD 15318, HIP 11484, HR 718, SAO 110543
Database references
SIMBAD	data

Xi² Ceti is a spectrophotometric standard star.^[2] It displays a stellar classification of B9.5III,^[3] which suggests it has exhausted its core hydrogen, evolved away from the main sequence, and expanded to become a giant star, although still only 127 million years old.^[7] It has 2.45^[7] times the mass and 2.6^[8] times the radius of the Sun.

In Chinese, 天囷 (Tiān Qūn), meaning Circular Celestial Granary, refers to an asterism consisting of α Ceti, κ¹ Ceti, λ Ceti, μ Ceti, ξ¹ Ceti, ξ² Ceti, ν Ceti, γ Ceti, δ Ceti, 75 Ceti, 70 Ceti, 63 Ceti and 66 Ceti. Consequently, the Chinese name for Xi² Ceti itself is "the Sixth Star of Circular Celestial Granary", Tiān Qūn Liù.^[10]