Tau5 Serpentis
Star in the constellation Serpens
From Wikipedia, the free encyclopedia
Tau5 Serpentis, Latinized from Ï5 Serpentis, is a star in the constellation of Serpens. The Flamsteed designation for this star is 18 Serpentis.[3] It has an apparent visual magnitude of 5.93,[1] which is bright enough to be dimly visible to the naked eye. The star is located at a distance of 169 light years from the Sun based on parallax measurements.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Serpens[1] |
| Right ascension | 15h 36m 29.240s[2] |
| Declination | +16° 07â² 08.70â³[2] |
| Apparent magnitude (V) | 5.93[1] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | F3V[3] |
| UâB color index | +0.04[4] |
| BâV color index | +0.354±0.004[1] |
| Astrometry | |
| Radial velocity (Rv) | â2.0±3.7[5] km/s |
| Proper motion (μ) | RA: 72.175 mas/yr[2] Dec.: â5.217 mas/yr[2] |
| Parallax (Ï) | 19.2694±0.0392 mas[2] |
| Distance | 169.3 ± 0.3 ly (51.9 ± 0.1 pc) |
| Absolute magnitude (MV) | +2.35[1] |
| Details | |
| Mass | 1.54[5] Mâ |
| Luminosity | 10[1] Lâ |
| Surface gravity (log g) | 3.96[5] cgs |
| Temperature | 6,903±80[5] K |
| Metallicity [Fe/H] | â0.20[5] dex |
| Rotational velocity (v sin i) | 88±10[6] km/s |
| Age | 1.90[5] Gyr |
| Other designations | |
| Ï5 Ser, 18 Serpentis, BD+16°2807, GC 20985, HD 139225, HIP 76424, HR 5804, SAO 101642, PPM 131544[3] | |
| Database references | |
| SIMBAD | data |
The stellar classification of this star is F3V,[3] matching an F-type main-sequence star. It has 1.54 times the mass of the Sun[5] and is radiating 10[1] times the Sun's luminosity from its photosphere at an effective temperature of 6,903 K.[5] The star has an estimated age of 1.9 billion years[5] and is spinning with a projected rotational velocity of about 88 km/s.[6] It is metal poor, which means the abundance of iron in the stellar atmosphere is lower than in the Sun.[5]
