WR 128
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sagitta |
| Right ascension | 19h 48m 32.19674s |
| Declination | +18° 12′ 03.6956″ |
| Apparent magnitude (V) | 10.51 |
| Characteristics | |
| Evolutionary stage | Wolf-Rayet |
| Spectral type | WN4(h)-w |
| U−B color index | −0.89 |
| B−V color index | −0.02 |
| Astrometry | |
| Radial velocity (Rv) | 100.00 km/s |
| Proper motion (μ) | RA: −0.233 mas/yr Dec.: −5.455 mas/yr |
| Parallax (π) | 0.2836±0.0202 mas |
| Distance | 2,900+540 −390 pc |
| Absolute magnitude (MV) | −3.27 |
| Details | |
| Mass | 11 M☉ |
| Radius | 2.69 R☉ |
| Luminosity | 166,000 L☉ |
| Temperature | 70,800 K |
| Other designations | |
| QT Sagittae, HD 187282, WR 128, HIP 97456, 2MASS J19483219+1812036 | |
| Database references | |
| SIMBAD | data |
WR 128 is a Wolf–Rayet star located about 9,500 light years away in the constellation of Sagitta. A member of the WN class, WR 128's spectrum resembles that of a WN4 star, but hydrogen is clearly present in the star (hence the h in its spectrum), making it the only known hydrogen-rich WN4 star in the galaxy. However, similar H-rich very early WN stars can be found in the LMC and especially in the SMC, but the only other galactic examples of this are WR 3 and WR 152.