  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda[1] |
| Right ascension | 01h 30m 06.10151s[2] |
| Declination | +47° 00′ 26.1811″[2] |
| Apparent magnitude (V) | 5.269[3] |
| Characteristics | |
| Evolutionary stage | red clump[4] |
| Spectral type | K0 III[5] |
| B−Vcolor index | 0.993[3] |
| Astrometry | |
| Radial velocity (Rv) | −11.48[3] km/s |
| Proper motion (μ) | RA: −0.950mas/yr[2] Dec.: −42.638mas/yr[2] |
| Parallax (π) | 9.7947±0.1166 mas[2] |
| Distance | 333 ± 4 ly (102 ± 1 pc) |
| Absolute magnitude (MV) | 0.50[1] |
| Details | |
| Mass | 2.07[3] M☉ |
| Radius | 11[6] R☉ |
| Luminosity | 70.8[3] L☉ |
| Surface gravity (log g) | 2.30[4] cgs |
| Temperature | 4,879±106[3] K |
| Metallicity[Fe/H] | +0.020±0.04[4] dex |
| Rotational velocity (v sin i) | 2.0[7] km/s |
| Age | 1.75[3] Gyr |
| Other designations | |
| a And[8],49 And,BD+46°370,HD 9057,HIP 6999,HR 430,SAO 37275,PPM 44057,GSC 03282-02272[9] | |
| Database references | |
| SIMBAD | data |
49 Andromedae is astar in theconstellationAndromeda.[1]49 Andromedae is theFlamsteed designation (abbreviated49 And),[9] though it also bears theBayer designationa Andromedae.[8] It is visible to thenaked eye under good viewing conditions with anapparent visual magnitude of 5.269.[3] The distance to 49 Andromedae, as determined from its annualparallax shift of9.8 mas,[2] is around 333 light-years. It is drifting closer to theSun with a heliocentricradial velocity of −11.5 km/s.[3]
With an estimated age of1.75 Gyr[3] years, this is an agingred-clump[4]giant star with astellar classification of K0 III,[5] indicating it is generating energy byhelium fusion at itscore. Thespectrum displays "slightly strong"absorption lines ofcyanogen (CN).[5] It has 2.07[3] times themass of the Sun and has expanded to 11[6] times theSun's radius. The star is radiating 71[3] times theSun's luminosity from its enlargedphotosphere at aneffective temperature of4,879 K.[3] It is spinning with aprojected rotational velocity of2 km/s.[7]
This was one of the stars historically known asAdhil, from Arabicað-ðayl "thetrain [of a garment]", a name now applied toξ Andromedae.[10] In a 1971 NASA technical memorandum listing star names, 49 Andromedae was listed asThail, likely derived from the same Arabic name.[11]
