Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Andromeda |
Right ascension | 00h 57m 12.4000s[1] |
Declination | +23° 25′ 03.533″[1] |
Apparent magnitude (V) | 4.403[1] |
Characteristics | |
Spectral type | G8III-IV + G8III-IV[2] |
U−B color index | +0.69[3] |
B−V color index | +0.94[3] |
R−I color index | +0.48[3] |
Astrometry | |
η And A | |
Radial velocity (Rv) | −10.3 ± 0.9[1] km/s |
Proper motion (μ) | RA: −43.72[1] mas/yr Dec.: −46.06[1] mas/yr |
Parallax (π) | 13.44 ± 0.75 mas[1] |
Distance | 240 ± 10 ly (74 ± 4 pc) |
Absolute magnitude (MV) | 0.52 ± 0.06[2] |
η And B | |
Absolute magnitude (MV) | 1.07 ± 0.07[2] |
Orbit[2] | |
Period (P) | 115.72 ± 0.01 d |
Semi-major axis (a) | 10.37 ± 0.03 mas |
Eccentricity (e) | 0.006 ± 0.002 |
Inclination (i) | 30.5 ± 0.4° |
Longitude of the node (Ω) | 69.4 ± 0.5° |
Periastron epoch (T) | 48013 ± 1 MJD |
Argument of periastron (ω) (secondary) | 215 ± 4° |
Details | |
η And A | |
Mass | 2.6 ± 0.35[4] M☉ |
Luminosity (bolometric) | 65 ± 3[2] L☉ |
Surface gravity (log g) | 2.8[2] cgs |
Temperature | 4900[2] K |
Age | 800 Million years |
η And B | |
Mass | 2.3 ± 0.31[4] M☉ |
Luminosity (bolometric) | 39 ± 3[2] L☉ |
Surface gravity (log g) | 3.0[2] cgs |
Temperature | 4900[2] K |
Other designations | |
Database references | |
SIMBAD | data |
Eta Andromedae (Eta And, η Andromedae, η And) is a spectroscopic binary star in the constellation of Andromeda. It consists of two G-type subgiant or giant stars orbiting each other with a period of 115.7 days and has an overall apparent visual magnitude of approximately 4.403.[1][2]
wds
was invoked but never defined (see the help page).