WR 31a
WR 31a is surrounded by a blue bubble nebula created by a powerful stellar wind impacting material expelled during earlier stages of the star's life. Credit: ESA/Hubble & NASA; Acknowledgement: Judy Schmidt | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Carina |
| Right ascension | 10h 53m 59.5777s |
| Declination | −60° 26′ 44.361″ |
| Apparent magnitude (V) | 10.85 |
| Characteristics | |
| Evolutionary stage | Wolf–Rayet |
| Spectral type | WN11h |
| Apparent magnitude (B) | 11.64±0.10 |
| Apparent magnitude (V) | 10.85±0.08 |
| Apparent magnitude (R) | 10.56±0.02 |
| Apparent magnitude (G) | 10.033±0.004 |
| Apparent magnitude (J) | 7.323±0.024 |
| Apparent magnitude (H) | 6.72±0.05 |
| Apparent magnitude (K) | 6.097±0.021 |
| Apparent magnitude (g) | 11.53±0.32 |
| B−V color index | 0.79 |
| V−R color index | 0.29 |
| R−I color index | 0.5 |
| J−H color index | 0.603 |
| J−K color index | 1.226 |
| Variable type | cLBV |
| Astrometry | |
| Proper motion (μ) | RA: −5.890 mas/yr Dec.: 2.842 mas/yr |
| Parallax (π) | 0.1152±0.0131 mas |
| Distance | approx. 28,000 ly (approx. 8,700 pc) |
| Absolute magnitude (MV) | −6.71 |
| Details | |
| Mass | 17+7 −4 M☉ |
| Radius | 29.8+11.9 −6.1 R☉ |
| Luminosity | 1,820,000 L☉ |
| Temperature | 30,200 (1985–1992) 27,500 (1991) K |
| Other designations | |
| WR 31a, Hen 3-519, He 3-519, 2MASS J10535958-6026444, GSC 08958-01166, GSC2 S1113013697, UCAC2 5308747, UCAC4 148-066854, IRAS 10520-6010, TYC 8928-1166-1, AAVSO 1050–59, MSX5C G288.9347-00.8046 | |
| Database references | |
| SIMBAD | data |
WR 31a, commonly referred to as Hen 3-519, is a Wolf–Rayet (WR) star in the southern constellation of Carina that is surrounded by an expanding Wolf–Rayet nebula. It is not a classical old stripped-envelope WR star, but a young massive star which still has some hydrogen left in its atmosphere.