HD 74438
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Vela |
| Right ascension | 08h 41m 46.5806s |
| Declination | −52° 03′ 44.996″ |
| Apparent magnitude (V) | +7.59 (8.2/8.2/9.4/9.4) |
| Characteristics | |
| Spectral type | A2mA5-A8 |
| Astrometry | |
| Proper motion (μ) | RA: −17.745 mas/yr Dec.: +17.056 mas/yr |
| Parallax (π) | 6.9075±0.0755 mas |
| Distance | 472 ± 5 ly (145 ± 2 pc) |
| Absolute magnitude (MV) | +3.23 |
| Orbit | |
| Primary | AB |
| Name | CD |
| Period (P) | 2,074.2±3.5 days |
| Semi-major axis (a) | 5.54±0.04 au |
| Eccentricity (e) | 0.458±0.015 |
| Inclination (i) | 73.2 or 106.8° |
| Semi-amplitude (K1) (primary) | 12.8±0.3 km/s |
| Semi-amplitude (K2) (secondary) | 18.5±0.4 km/s |
| Orbit | |
| Primary | A |
| Name | B |
| Period (P) | 20.5729±0.0003 days |
| Semi-major axis (a) | 0.215±0.002 au |
| Eccentricity (e) | 0.3692±0.0001 |
| Inclination (i) | 52.5 or 127.5° |
| Semi-amplitude (K1) (primary) | 45.81±0.09 km/s |
| Semi-amplitude (K2) (secondary) | 50.77±0.09 km/s |
| Orbit | |
| Primary | C |
| Name | D |
| Period (P) | 4.4243±0.0001 days |
| Semi-major axis (a) | 0.0681±0.001 au |
| Eccentricity (e) | 0.1535±0.0003 |
| Inclination (i) | 84.0 or 96.0° |
| Semi-amplitude (K1) (primary) | 45.81±0.09 km/s |
| Semi-amplitude (K2) (secondary) | 50.77±0.09 km/s |
| Details | |
| A | |
| Mass | 1.70±0.06 M☉ |
| Radius | 1.46±0.15 R☉ |
| Luminosity | 8.87±1.40 L☉ |
| Temperature | 8,250±250 K |
| B | |
| Mass | 1.54±0.06 M☉ |
| Radius | 1.42±0.15 R☉ |
| Luminosity | 5.72±0.95 L☉ |
| Temperature | 7,500±250 K |
| C | |
| Mass | 0.96±0.14 M☉ |
| Radius | 0.84±0.36 R☉ |
| Luminosity | 0.64±0.51 L☉ |
| Temperature | 5,625±410 K |
| D | |
| Mass | 0.87±0.14 M☉ |
| Radius | 0.80±0.29 R☉ |
| Luminosity | 0.48±0.32 L☉ |
| Temperature | 5,375±410 K |
| Other designations | |
| HD 74438, CD−52°2497, SAO 236190 | |
| Database references | |
| SIMBAD | data |
HD 74438 is a spectroscopic quadruple stellar system composed of a pair of double star systems approximately 425 light years from Earth, located in the open cluster IC 2391. With an estimated age of 43+15
−7 million years, HD 74438 is the youngest quadruple star system known. The outer orbital period of the system, estimated at around 5.7 years, is also among the shortest of quadruple systems.
The HD 74438 system was confirmed to be a gravitationally bound quadruple system in 2017 from data collected in the Gaia-ESO Survey. In a paper published in 2022, HD 74438 was identified as a possible progenitor of a sub-Chandrasekhar Type Ia supernova.