3 Andromedae
3 Andromedae, abbreviated 3 And, is a single star in the northern constellation of Andromeda. 3 Andromedae is the Flamsteed designation. It is visible to the naked eye with an apparent visual magnitude of 4.64. The distance to this star, as determined from an annual parallax shift of 18 mas, is 181 light years. It is moving closer to the Earth with a heliocentric radial velocity of −35 km/s, and has a relatively large proper motion, traversing the celestial sphere at 0.236″·yr−1.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 23h 04m 10.98185s |
| Declination | +50° 03′ 07.5297″ |
| Apparent magnitude (V) | 4.64 |
| Characteristics | |
| Evolutionary stage | giant |
| Spectral type | K0 IIIb |
| B−V color index | 1.058±0.003 |
| Astrometry | |
| Radial velocity (Rv) | −34.7±0.3 km/s |
| Proper motion (μ) | RA: 166.374 mas/yr Dec.: 167.463 mas/yr |
| Parallax (π) | 17.9785 ± 0.1522 mas |
| Distance | 181 ± 2 ly (55.6 ± 0.5 pc) |
| Absolute magnitude (MV) | 0.97 |
| Details | |
| Mass | 1.71 M☉ |
| Radius | 10 R☉ |
| Luminosity | 49 L☉ |
| Surface gravity (log g) | 2.61±0.11 cgs |
| Temperature | 4,668±45 K |
| Metallicity [Fe/H] | −0.08 dex |
| Rotational velocity (v sin i) | 1.0 km/s |
| Age | 2.27 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved giant star with a stellar classification of K0 IIIb, where the 'b' suffix indicated a lower luminosity giant. It is a red clump star, which means it is generating energy through helium fusion at its core. This star has an estimated 1.7 times the mass of the Sun (M☉), and, at the age of 2.3 billion years, has expanded to 10 times the Sun's radius (R☉). It is radiating 49 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,668 K.