Xi Eridani

ξ Eridani (Latinised as Xi Eridani) is a solitary^[6] star in the constellation Eridanus. With an apparent visual magnitude of 5.17,^[2] it is faintly visible to the naked eye on a clear, dark night. Based upon an annual parallax shift of 0.00156 arcseconds,^[1] it is located around 209 light years from the Sun. The star is considered a member of the Sirius supercluster.^[5]

ξ Eridani

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Eridanus
Right ascension	04h 23m 40.85270s[1]
Declination	−03° 44′ 43.6771″[1]
Apparent magnitude (V)	5.17[2]
Characteristics
Spectral type	A2 V[3]
U−B color index	+0.08[2]
B−V color index	+0.08[2]
Astrometry
Radial velocity (Rv)	−11.0[4] km/s
Proper motion (μ)	RA: −47.36[1] mas/yr Dec.: −54.91[1] mas/yr
Parallax (π)	15.60±0.25 mas[1]
Distance	209 ± 3 ly (64 ± 1 pc)
Absolute magnitude (MV)	+1.59[5]
Details
Mass	2.29[6] M☉
Radius	2.2[7] R☉
Luminosity	27.6[8] L☉
Surface gravity (log g)	3.73[9] cgs
Temperature	8,400[8] K
Rotational velocity (v sin i)	194.3±2.3[3] km/s
Age	450[6] Myr
Other designations
ξ Eri, BD−04°818, 42 Eridani, FK5 1120, HD 27861, HIP 20507, HR 1383, SAO 131176[10]
Database references
SIMBAD	data

This is an ordinary A-type main sequence star with a stellar classification of A2 V,^[3] indicating that it is generating energy through the thermonuclear fusion of hydrogen into helium in its core region. It is around 450^[6] million years old and has a relatively high rate of rotation with a projected rotational velocity of 194 km/s.^[3] The star has about 2.3 times the mass of the Sun,^[6] 2.2 times the Sun's radius,^[7] and radiates 27.6^[8] times the solar luminosity from its outer atmosphere at an effective temperature of 8,400 K.^[8]