36 Serpentis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 51m 15.59418s |
| Declination | −03° 05′ 25.7938″ |
| Apparent magnitude (V) | 5.09 (5.2 + 7.8) |
| Characteristics | |
| Spectral type | A3Vn or A2IV-Vn (A7 + G0) |
| U−B color index | +0.07 |
| B−V color index | +0.12 |
| Astrometry | |
| Radial velocity (Rv) | −8 km/s |
| Proper motion (μ) | RA: −91.09 mas/yr Dec.: −28.21 mas/yr |
| Parallax (π) | 20.10±0.33 mas |
| Distance | 162 ± 3 ly (49.8 ± 0.8 pc) |
| Absolute magnitude (MV) | 1.61 |
| Orbit | |
| Primary | 36 Ser A |
| Companion | 36 Ser B |
| Period (P) | 1,073 days |
| Eccentricity (e) | 0.7 |
| Semi-amplitude (K1) (primary) | 6 km/s |
| Orbit | |
| Primary | 36 Ser AB |
| Companion | 36 Ser C |
| Period (P) | 50.6±1.5 yr |
| Semi-major axis (a) | 0.400±0.006″ |
| Eccentricity (e) | 0.8323±0.0047 |
| Inclination (i) | 98.08±0.31° |
| Longitude of the node (Ω) | 74.00±0.31° |
| Periastron epoch (T) | 2002.78±0.17 |
| Argument of periastron (ω) (secondary) | 72.84±0.91° |
| Details | |
| 36 Ser A | |
| Mass | 1.97 M☉ |
| Radius | 2.25 R☉ |
| Luminosity | 19.13 L☉ |
| Surface gravity (log g) | 3.89 cgs |
| Temperature | 8,213 K |
| Metallicity [Fe/H] | −2.00 dex |
| Rotational velocity (v sin i) | 229 km/s |
| Age | 710 Myr |
| 36 Ser B | |
| Mass | ≥0.37 and ≤0.50 M☉ |
| 36 Ser C | |
| Mass | 1.27 M☉ |
| Radius | 1.26 R☉ |
| Temperature | 6,255 K |
| Age | 710 Myr |
| Other designations | |
| b Ser, 36 Ser, BD−02°4058, FK5 2249, GC 4210, HD 141851, HIP 77660, HR 5895, SAO 140801, WDS J15513-0305 | |
| Database references | |
| SIMBAD | data |
36 Serpentis is a triple star system in the equatorial constellation of Serpens. It has the Bayer designation b Serpentis, while 36 Serpentis is the Flamsteed designation. The system is visible to the naked eye as a dim, white-hued point of light with a combined apparent visual magnitude of 5.09. It is located 162 light years away from the Sun based on parallax, and is moving closer with a radial velocity of −8 km/s.