Epsilon 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[1] |
| Declination | +29° 18′ 42.305″[1] |
| Apparent magnitude (V) | 4.37[1] |
| Characteristics | |
| Spectral type | G6IIIFe-3CH1[2] |
| U−B color index | +0.47[2] |
| B−V color index | +0.87[2] |
| V−R color index | 0.6[1] |
| R−I color index | +0.51[2] |
| Astrometry | |
| Radial velocity (Rv) | −83.6 ± 0.9[1] km/s |
| Proper motion (μ) | RA: −229.42[1] mas/yr Dec.: −254.09[1] mas/yr |
| Parallax (π) | 19.34 ± 0.76[1] mas |
| Distance | 169 ± 7 ly (52 ± 2 pc) |
| Absolute magnitude (MV) | 0.8[3] |
| Details | |
| Mass | 2.4[4] M☉ |
| Radius | 9.8[5] R☉ |
| Luminosity | 52[4] L☉ |
| Temperature | 4930[4] K |
| Rotational velocity (v sin i) | 9[2] km/s |
| Age | 650[4] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Coordinates: 
00h 38m 33.3458s, +29° 18′ 42.305″
Epsilon Andromedae (Epsilon And, ε Andromedae, ε And) is a G-type giant star in the constellation of Andromeda.[1] It has an apparent visual magnitude of approximately 4.37.[1]
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.[4]
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.)[6]
References
- 1 2 3 4 5 6 7 8 9 10 11 NLTT 2065 -- High proper-motion Star, database entry, SIMBAD. Accessed on line August 28, 2008.
- 1 2 3 4 5 HR 163, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line August 28, 2008.
- ↑ From parallax and apparent magnitude.
- 1 2 3 4 5 Epsilon Andromedae, Stars, Jim Kaler. Accessed on line August 28, 2008.
- ↑ Nordgren, Tyler E.; et al. (December 1999), "Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer", The Astronomical Journal, 118 (6): 3032–3038, Bibcode:1999AJ....118.3032N, doi:10.1086/301114
- ↑ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日