Feige 55 is a hot white dwarf approximately 650 light-years away from the Sun in the constellation of Ursa Major. The star is likely a post-AGB star with relatively high luminosity for a standard white dwarf. It is also in a close binary system with orbital period of 1.4933 days.[3]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 12h 04m 38.5357s[1] |
| Declination | +60° 32′ 08.0865″[1] |
| Apparent magnitude (V) | +13.45 |
| Characteristics | |
| Spectral type | DAO+M5.5V |
| Astrometry | |
| Proper motion (μ) | RA: −54.744±0.065[1] mas/yr Dec.: −34.855±0.061[1] mas/yr |
| Parallax (π) | 5.0141 ± 0.0419 mas[1] |
| Distance | 650 ± 5 ly (199 ± 2 pc) |
| Details | |
| Mass | 0.486/0.3 M☉ |
| Radius | 0.0345/0.33? R☉ |
| Luminosity | 10.7/0.0079 L☉ |
| Temperature | 56,300/3000? K |
| Other designations | |
| Database references | |
| SIMBAD | data |