HD 3322
HD 3322 is a binary star system in the northern constellation of Andromeda. With an apparent visual magnitude of 6.51, it lies below the nominal brightness limit for visibility with the normal naked eye, but it is still possible to see the star with excellent vision under ideal seeing conditions. An annual parallax shift of 4.59±0.65 mas provides a distance estimate of roughly 700 light years.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 00h 36m 20.09863s |
| Declination | +27° 15′ 17.1519″ |
| Apparent magnitude (V) | 6.51 |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | B8.5 IIIp HgMn |
| B−V color index | −0.070±0.011 |
| Variable type | α2 CVn |
| Astrometry | |
| Radial velocity (Rv) | +4.0±7.4 km/s |
| Proper motion (μ) | RA: +15.96 mas/yr Dec.: −11.11 mas/yr |
| Parallax (π) | 4.59 ± 0.65 mas |
| Distance | approx. 700 ly (approx. 220 pc) |
| Absolute magnitude (MV) | −0.13 |
| Orbit | |
| Period (P) | 399.6±2.1 d |
| Eccentricity (e) | 0.57±0.09 |
| Periastron epoch (T) | 2440462.38 ± 6.05 JD |
| Argument of periastron (ω) (secondary) | 304±11° |
| Semi-amplitude (K1) (primary) | 8.07±1.07 km/s |
| Details | |
| HD 3322 A | |
| Mass | 3.68±0.21 M☉ |
| Radius | 4.8 R☉ |
| Luminosity | 246+91 −66 L☉ |
| Surface gravity (log g) | 3.821±0.056 cgs |
| Temperature | 12,882+90 −88 K |
| Rotational velocity (v sin i) | 14 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a single-lined spectroscopic binary star system with an orbital period of around 400 days and an eccentricity of 0.57. The visible component has a stellar classification of B8.5 IIIp HgMn, matching a chemically peculiar B-type giant mercury-manganese star. Catalano and Leone (1991) found it to be a α2 CVn variable with a period of 4.6904 days, and thus it received the variable star designation PY And. It has an estimated 3.7 times the mass of the Sun and about 4.8 times the Sun's radius. It is radiating around 246 times the Sun's luminosity from its photosphere at an effective temperature of 12,882 K.