6 Serpentis
Star in the constellation Serpens
From Wikipedia, the free encyclopedia
6 Serpentis is a binary star[3] system in the constellation Serpens. It has a combined apparent visual magnitude of 5.382,[2] which is bright enough to be faintly visible to the naked eye. The distance to this system, based upon an annual parallax shift of 13.63±0.73 mas,[1] is about 240 light years. It is moving further from the Sun with a heliocentric radial velocity of +10 km/s.[4]
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 21m 01.99609s[1] |
| Declination | +00° 42′ 55.2213″[1] |
| Apparent magnitude (V) | 5.382[2] (5.54 + 9.42)[3] |
| Characteristics | |
| Spectral type | K3 III[2] |
| B−V color index | 1.224[2] |
| Astrometry | |
| Radial velocity (Rv) | +9.7±0.3[4] km/s |
| Proper motion (μ) | RA: −42.36[1] mas/yr Dec.: −103.14[1] mas/yr |
| Parallax (π) | 13.63±0.73 mas[1] |
| Distance | 240 ± 10 ly (73 ± 4 pc) |
| Absolute magnitude (MV) | 1.03[5] |
| Details[2] | |
| 6 Ser A | |
| Mass | 1.27 M☉ |
| Radius | 12[6] R☉ |
| Luminosity | 55 L☉ |
| Surface gravity (log g) | 2.4[6] cgs |
| Temperature | 4,417±17 K |
| Metallicity [Fe/H] | −0.02[7] dex |
| Rotational velocity (v sin i) | 2.4[6] km/s |
| Age | 6.03 Gyr |
| Other designations | |
| 6 Ser, BD+01°3067, HD 136514, HIP 75119, HR 5710, SAO 120955, ADS 9596, WDS J15210+0043[8] | |
| Database references | |
| SIMBAD | data |
The primary, component A, is an evolved red giant of spectral type K3III,[2] a star that has used up its core hydrogen and has expanded. At the age of around six billion years it is a red clump star,[7][9] indicating it is on the horizontal branch and is generating energy through helium fusion at its core. The star has 1.27[2] times the mass of the Sun and has expanded to 12[6] times the Sun's radius. It is radiating 55[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,417 K.[2]
As of 2005, the magnitude 9.42[3] secondary, component B, was at an angular separation of 3.329″±0.017″ along a position angle of 21.8°±0.3°.[10]