52 Hydrae
52 Hydrae is a triple star system in the constellation Hydra. It has the Bayer designation l Hydrae; 52 Hydrae is the Flamsteed designation. This system is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.97. It is a probable (80% chance) member of the Sco OB2 moving group of stars, and is moving away from the Earth with a heliocentric radial velocity of 5 km/s.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hydra |
| Right ascension | 14h 28m 10.42638s |
| Declination | −29° 29′ 29.8884″ |
| Apparent magnitude (V) | 4.97 (5.70 + 5.70 + 10.00) |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | B7/8V |
| B−V color index | −0.074±0.003 |
| Astrometry | |
| Radial velocity (Rv) | 5.4±3.8 km/s |
| Proper motion (μ) | RA: −25.23 mas/yr Dec.: −23.03 mas/yr |
| Parallax (π) | 8.29 ± 0.28 mas |
| Distance | 390 ± 10 ly (121 ± 4 pc) |
| Absolute magnitude (MV) | −0.43 |
| Details | |
| 52 Hya A | |
| Mass | 3.82±0.06 M☉ |
| Luminosity | 310.5+24.5 −22.8 L☉ |
| Temperature | 12,853±89 K |
| Rotational velocity (v sin i) | 204 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
The primary component is a binary system consisting of two nearly equal components with an orbital period of around 15 years and an angular separation of 0.1″. It shows a combined stellar classification of B7/8V, which matches a B-type main-sequence star. The third component is a magnitude 10.0 star at a separation of 4.2″ with a mass similar to the Sun. It is orbiting the inner pair with a period of around 3,900 years.