AM Herculis
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 18h 16m 13.255s |
| Declination | +49° 52′ 04.76″ |
| Apparent magnitude (V) | 12.30-15.7 |
| Characteristics | |
| Spectral type | pec + M4.5V |
| Variable type | AM/XRM+E |
| Astrometry | |
| Radial velocity (Rv) | -19.0 km/s |
| Proper motion (μ) | RA: −45.957 mas/yr Dec.: +28.046 mas/yr |
| Parallax (π) | 11.3953±0.0179 mas |
| Distance | 286.2 ± 0.4 ly (87.8 ± 0.1 pc) |
| Orbit | |
| Period (P) | 3.094 hours (variable) |
| Eccentricity (e) | 0.47±0.21 |
| Inclination (i) | 50° |
| Details | |
| White dwarf | |
| Mass | 0.6 - 0.7 M☉ |
| Red dwarf | |
| Mass | 0.26 M☉ |
| Radius | 0.32 R☉ |
| Other designations | |
| AN 1923.0028, GSC 3533.01105, X 18149+498 | |
| Database references | |
| SIMBAD | data |
AM Herculis is a binary variable star located in the constellation Hercules. This star, along with the star AN Ursae Majoris, is the prototype for a category of cataclysmic variable stars called polars, or AM Her type stars.