LS I +61 303
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 02h 40m 31.6644s |
| Declination | +61° 13′ 45.594″ |
| Apparent magnitude (V) | 10.61–10.83 |
| Characteristics | |
| Evolutionary stage | main sequence + pulsar |
| Spectral type | B0Ve |
| U−B color index | −0.34 |
| B−V color index | +0.86 |
| Variable type | High-mass X-ray binary |
| Astrometry | |
| Radial velocity (Rv) | +392.1 km/s |
| Proper motion (μ) | RA: −0.423 mas/yr Dec.: −0.256 mas/yr |
| Parallax (π) | 0.3776±0.0130 mas |
| Distance | 8,600 ± 300 ly (2,650 ± 90 pc) |
| Details | |
| Be star | |
| Mass | 14.6 M☉ |
| Radius | 6.9 R☉ |
| Luminosity | 50,000 L☉ |
| Surface gravity (log g) | 3.38 cgs |
| Temperature | 22,500 K |
| Other designations | |
| V615 Cas, 1RXS J024033.5+611358, TYC 4047-1917-1, HIP 12469 | |
| Database references | |
| SIMBAD | data |
LS I +61 303 is a binary system containing a massive star and a compact object. The compact object is a pulsar and the system is around 7,000 light-years away.