Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Andromeda |
Right ascension | 00h 21m 07.26896s[1] |
Declination | +37° 58′ 06.9727″[1] |
Apparent magnitude (V) | +5.19[2] |
Characteristics | |
Spectral type | F5IV-V[3] |
U−B color index | +0.039[2] |
B−V color index | +0.424[2] |
Astrometry | |
Radial velocity (Rv) | +10.4±0.6[4] km/s |
Proper motion (μ) | RA: +57.599[1] mas/yr Dec.: –38.378[1] mas/yr |
Parallax (π) | 20.1874 ± 0.1179 mas[1] |
Distance | 161.6 ± 0.9 ly (49.5 ± 0.3 pc) |
Absolute magnitude (MV) | +1.73[5] |
Details | |
Radius | 3.37+0.07 −0.03[1] R☉ |
Luminosity | 17.93±0.13[1] L☉ |
Surface gravity (log g) | 3.84[6] cgs |
Temperature | 6,471+25 −66[1] K |
Metallicity [Fe/H] | –0.09[6] dex |
Rotational velocity (v sin i) | 44[6] km/s |
Age | 1.3[5] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Rho Andromedae, Latinized from ρ Andromedae, is the Bayer designation for a star in the northern constellation of Andromeda. It has an apparent visual magnitude of +5.19,[2] which, according to the Bortle Dark-Sky Scale, is bright enough to be seen with the naked eye from dark suburban skies. Based upon parallax measurements, this star is at a distance of approximately 162 light-years (50 parsecs) from the Sun.[1] It is drifting further away with a radial velocity of +10 km/s.[4]
The stellar classification of this star is F5IV-V,[3] showing mixed spectral features of a main sequence and subgiant stage. It is about 1.3[5] billion years old with 3.4[1] times the girth of the Sun and is spinning with a projected rotational velocity of 44 km/s.[6] The outer envelope is radiating around 18 times the luminosity of the Sun from its photosphere at an effective temperature of 6,471 K,[1] giving it the yellow-white hue of an F-type star.[8] X-ray emissions were detected from this star during the EXOSAT mission.[9]
In Chinese, 天廄 (Tiān Jiù), meaning Celestial Stable, refers to an asterism consisting of ρ Andromedae, θ Andromedae and σ Andromedae. Consequently, the Chinese name for ρ Andromedae itself is 天廄二 (Tiān Jiù èr, English: the Second Star of Celestial Stable.)[10]