R136a1
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Dorado |
| Right ascension | 5h 38m 42.39s |
| Declination | −69° 06′ 02.91″ |
| Apparent magnitude (V) | 12.23 |
| Characteristics | |
| Evolutionary stage | Wolf–Rayet star |
| Spectral type | WN5h |
| B−V color index | 0.03 |
| Astrometry | |
| Distance | 163,000 ly (49,970 pc) |
| Absolute magnitude (MV) | −8.18 |
| Details | |
| Mass | 196+34 −27 M☉ |
| Radius | 42.7 R☉ |
| Luminosity | 4,677,000 L☉ |
| Surface gravity (log g) | 3.65 cgs |
| Temperature | 46,000+1,250 −2,375 K |
| Rotational velocity (v sin i) | 160 km/s |
| Age | 1.14+0.17 −0.14 Myr |
| Other designations | |
| BAT99 108, RMC 136a1, HSH95 3, WO84 1b, NGC 2070 MH 498, CHH92 1, P93 954 | |
| Database references | |
| SIMBAD | data |
R136a1 (short for RMC 136a1) is one of the most massive and luminous stars known, at nearly 200 M☉ and nearly 4.7 million L☉, and is also one of the hottest, at around 46,000 K. It is a Wolf–Rayet star at the center of R136, the central concentration of stars of the large NGC 2070 open cluster in the Tarantula Nebula (30 Doradus) in the Large Magellanic Cloud. The cluster can be seen in the far southern celestial hemisphere with binoculars or a small telescope, at magnitude 7.25. R136a1 itself is 100 times fainter than the cluster and can only be resolved using speckle interferometry.