WASP-8
WASP-8 is a binary star system 294 light-years (90 parsecs) away. The star system is much younger than the Sun at 300 million to 1.2 billion years age, and is heavily enriched in heavy elements, having nearly twice the concentration of iron compared to the Sun.
Artist's impression of a star like WASP-8 | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sculptor |
| Right ascension | 23h 59m 36.07119s |
| Declination | −35° 01′ 52.9236″ |
| Apparent magnitude (V) | 9.87 |
| Characteristics | |
| WASP-8A | |
| Evolutionary stage | main-sequence |
| Spectral type | G8V |
| WASP-8B | |
| Spectral type | M |
| Astrometry | |
| Radial velocity (Rv) | −1.38±0.26 km/s |
| Proper motion (μ) | RA: 109.752 mas/yr Dec.: 7.615 mas/yr |
| Parallax (π) | 11.1052 ± 0.0175 mas |
| Distance | 293.7 ± 0.5 ly (90.0 ± 0.1 pc) |
| Position (relative to WASP-8A) | |
| Component | WASP-8B |
| Epoch of observation | 2016 |
| Angular distance | 4.520±0.005″ |
| Position angle | 170.9±0.1° |
| Projected separation | 408 AU |
| Details | |
| WASP-8A | |
| Mass | 1.093±0.024 M☉ |
| Radius | 0.976±0.020 R☉ |
| Luminosity | 0.79 L☉ |
| Surface gravity (log g) | 4.498±0.018 cgs |
| Temperature | 5600±80 K |
| Metallicity [Fe/H] | 0.29±0.03 dex |
| Rotational velocity (v sin i) | 1.90±0.05 km/s |
| Age | 0.3+0.9 −0.1 Gyr |
| WASP-8B | |
| Mass | 0.53±0.02 M☉ |
| Temperature | 3758+47 −43 K |
| Other designations | |
| Database references | |
| SIMBAD | A |
| B | |
The primary, WASP-8A, is a magnitude 9.9 main-sequence yellow dwarf star. It is reported to be a G-type star with a temperature of 5600 K and has a mass 1.093±0.024, a radius 0.976±0.020 and a luminosity of 0.79 times that of the Sun. There is a companion star WASP-8B located 4.5 arcseconds away with the same proper motion, indicating a stellar binary system. The binarity was confirmed in 2020. The axis orientation of the primary star is uncertain, but it is close to pointing one of the poles to the Earth.