Xi Arietis

Xi Arietis is a binary star^[9] system in the northern constellation of Aries. Its name is a Bayer designation that is Latinized from ξ Arietis, and abbreviated Xi Ari or ξ Ari. This system has an apparent visual magnitude of 5.46,^[2] and so is dimly visible to the naked eye. Based upon an annual parallax shift of 3.74±0.29 mas as seen from Earth, it is 770 ± 30 light-years (236.1 ± 9.2 parsecs) distant from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.24 due to interstellar dust.^[5] The proximity of this system to the ecliptic means it is subject to lunar occultations.^[10]

Xi Arietis

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Aries
Right ascension	02h 24m 49.058s[1]
Declination	+10° 36′ 38.01″[1]
Apparent magnitude (V)	+5.46[2]
Characteristics
Spectral type	B7 IV[3]
U−B color index	−0.48[2]
B−V color index	−0.10[2]
Astrometry
Radial velocity (Rv)	−0.5±2.8[4] km/s
Proper motion (μ)	RA: +20.979 mas/yr[1] Dec.: −15.022 mas/yr[1]
Parallax (π)	4.2483±0.1511 mas[1]
Distance	770 ± 30 ly (235 ± 8 pc)
Absolute magnitude (MV)	−0.43[5]
Details
Mass	4.85±0.13[6] M☉
Luminosity	1,000+186 −157[6] L☉
Surface gravity (log g)	3.897±0.017[7] cgs
Temperature	13,627±100[7] K
Rotational velocity (v sin i)	164±8[7] km/s
Age	195[5] Myr
Other designations
ξ Ari, ψ Ceti, 24 Arietis, BD+09°316, FK5 2164, GC 2901, HD 14951, HIP 11249, HR 702, SAO 92932, PPM 118200[8]
Database references
SIMBAD	data

This is a double-lined spectroscopic binary.^[9] The spectrum matches a stellar classification of B7 IV,^[3] which suggests a subgiant star that has exhausted the supply of hydrogen at its core and is in the process of evolving into a giant star. Xi Arietis was once a designation for Psi Ceti (ψ Cet, ψ Ceti), and was later recognized to be a duplicate by Bayer.^[11]