HD 156091 is a double star in the southern constellation of Ara. The primary is a sixth magnitude giant star with stronger than normal lines of carbon, nitrogen, and barium in its spectrum.[8] The companion is a 13th magnitude star at an angular separation of 27.4″ along a position angle of 275°, as of 2000.[3]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ara |
| Right ascension | 17h 19m 12.50730s[1] |
| Declination | −59° 41′ 40.5989″[1] |
| Apparent magnitude (V) | 5.91[2] (5.91 + 13.00)[3] |
| Characteristics | |
| Spectral type | K2 IIICNIB/II[4] |
| B−V color index | 1.37[2] |
| Astrometry | |
| Radial velocity (Rv) | −5.0±0.4[5] km/s |
| Proper motion (μ) | RA: −3.15[1] mas/yr Dec.: −8.05[1] mas/yr |
| Parallax (π) | 1.31 ± 0.36 mas[1] |
| Distance | approx. 2,500 ly (approx. 800 pc) |
| Details | |
| Mass | 8.4±1.0[6] M☉ |
| Luminosity | 4,266[7] L☉ |
| Temperature | 4,306[7] K |
| Age | 33.7±8.6[6] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |