Epsilon Andromedae

ε Andromedae

Location of ε Andromedae (lower left of center)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Andromeda
Right ascension	00h 38m 33.3458s
Declination	+29° 18′ 42.305″
Apparent magnitude (V)	4.37
Characteristics
Spectral type	G6IIIFe-3CH1
U−B color index	+0.47
B−V color index	+0.87
V−R color index	0.6
R−I color index	+0.51
Astrometry
Radial velocity (Rv)	−83.6 ± 0.9 km/s
Proper motion (μ)	RA: −229.42 mas/yr Dec.: −254.09 mas/yr
Parallax (π)	19.34 ± 0.76 mas
Distance	169 ± 7 ly (52 ± 2 pc)
Absolute magnitude (MV)	0.8
Details
Mass	2.4 M☉
Radius	9.8 R☉
Luminosity	52 L☉
Temperature	4930 K
Rotational velocity (v sin i)	9 km/s
Age	650 Myr
Other designations
ε And, Epsilon Andromedae, Epsilon And, 30 Andromedae, 30 And, BD+28 103, FK5 19, GC 759, HD 3546, HIP 3031, HR 163, LTT 10215, NLTT 2065, PPM 90002, SAO 74164.
Database references
SIMBAD	data

Epsilon Andromedae (Epsilon And, ε Andromedae, ε And) is a G-type giant star in the constellation of Andromeda. It has an apparent visual magnitude of approximately 4.37.

ε Andromedae is believed to be a red clump star which is fusing helium in its core. Its orbit in the Milky Way is highly eccentric, causing it to move rapidly relative to the Sun and its neighboring stars.

Naming

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism consisting of ε Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, δ Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, ε Andromedae itself is known as 奎宿四 (Kuí Sù sì, English: the Fourth Star of Legs.)

External links

• Image Epsilon Andromedae