WASP-59 b
Astrophysical Synthesis & Habitability Characterization
WASP-59 b is a confirmed gas giant exoplanet orbiting the star WASP-59, located approximately 378.1 light-years (115.94 parsecs) from the Solar System. First announced in 2012 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.688% across the stellar disk), this world measures 8.687 Earth radii (0.78 Jupiter radii) and has a measured mass of 274.276 Earth masses (0.86 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.31 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 3.63 g⊕ (35.6 m/s²), and an escape velocity of 62.9 km/s.
In its orbital architecture around WASP-59, WASP-59 b completes one full revolution every 7.92 Earth days at a semi-major axis of 0.0697 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 95.7 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.1 carries the world between 0.0627 AU at periapsis and 0.0767 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 670 K (+397°C / +747°F) and receiving 38.03 S⊕ (~51,763 W/m²), WASP-59 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-59 is classified as an orange K-type star of spectral type K5 V with an effective photospheric temperature of 4,650 K, a radius of 0.613 R☉, a mass of 0.719 M☉, an estimated bolometric luminosity of 0.158 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.5 Gyr and a metallicity of [Fe/H] = -0.15 dex (metal-poor relative to the Sun). From Earth, WASP-59 shines at apparent V-band magnitude 12.659 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: SuperWASP · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | WASP-59 |
| Spectral Type | K5 V |
| Effective Temp (Teff) | 4,650 K |
| Stellar Radius | 0.6130 R☉ |
| Stellar Mass | 0.7190 M☉ |
| Bolometric Luminosity | 0.158 L☉ |
| Metallicity [Fe/H] | -0.150 dex |
| Stellar Age | 0.500 Gyr |
| Apparent Magnitude | V: 12.659 · G: 12.314 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.069700 AU |
| Orbital Period | 7.92 days |
| Mean Orbital Velocity | 95.7 km/s |
| Orbital Eccentricity (e) | 0.10000 |
| Orbital Inclination (i) | 89.2700° |
| Mean Bulk Density | 2.31 g/cm³ (62.9 km/s vesc) |
| Insolation Flux | 38.0328 S⊕ (~51,763 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 378.100 LY (115.936 pc) |