HD 223960
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 23h 53m 49.98300s |
| Declination | +60° 51′ 12.2438″ |
| Characteristics | |
| Evolutionary stage | blue supergiant |
| Spectral type | B9Ia |
| U−B color index | −0.050 |
| B−V color index | +0.715 |
| Variable type | α Cyg |
| Astrometry | |
| Radial velocity (Rv) | −48.1 km/s |
| Proper motion (μ) | RA: −3.009 mas/yr Dec.: −2.205 mas/yr |
| Parallax (π) | 0.3413±0.0147 mas |
| Distance | 9,600 ± 400 ly (2,900 ± 100 pc) |
| Absolute magnitude (MV) | −6.9 |
| Details | |
| Mass | 19.2 M☉ |
| Radius | 89 R☉ |
| Luminosity | 315,000+99,000 −75,000 L☉ |
| Surface gravity (log g) | 1.48±0.10 cgs |
| Temperature | 10,700±200 K |
| Metallicity [Fe/H] | +0.02 dex |
| Rotational velocity (v sin i) | 32 km/s |
| Other designations | |
| V819 Cassiopeiae, BD+60°2636, HD 223960, HIP 117830 | |
| Database references | |
| SIMBAD | data |
HD 223960 is a supergiant star in the northern constellation Cassiopeia. Its brightness varies slightly around apparent magnitude 7 which makes it hard to be seen by the naked eye even from dark skies. Parallax measurements by the Gaia spacecraft suggest a distance of around 9,600 light years.
HD 223960 is tentatively classified as an α Cygni variable; its brightness changes erratically by less than a tenth of a magnitude with a primary period of about two days. It is a hot supergiant star with a luminosity several hundred thousand times higher than the Sun's.