WASP-13 b
Astrophysical Synthesis & Habitability Characterization
WASP-13 b is a confirmed gas giant exoplanet orbiting the star WASP-13, located approximately 742.1 light-years (227.54 parsecs) from the Solar System. First announced in 2009 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 0.8374% across the stellar disk), this world measures 13.675 Earth radii (1.22 Jupiter radii) and has a measured mass of 114.419 Earth masses (0.36 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.25 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.61 g⊕ (5.98 m/s²), and an escape velocity of 32.4 km/s.
In its orbital architecture around WASP-13, WASP-13 b completes one full revolution every 4.353 Earth days at a semi-major axis of 0.05362 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 134 km/s (compared to Earth's 29.8 km/s). The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1531 K (+1258°C / +2296°F) and receiving 617.31 S⊕ (~840,158 W/m²), WASP-13 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-13 is classified as a stellar host with an effective photospheric temperature of 5,950 K, a radius of 1.37 R☉, a mass of 0.72 M☉, an estimated bolometric luminosity of 2.111 L☉. Stellar evolution modeling indicates an estimated stellar age of 5 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, WASP-13 shines at apparent V-band magnitude 10.424 (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-13 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,950 K |
| Stellar Radius | 1.3700 R☉ |
| Stellar Mass | 0.7200 M☉ |
| Bolometric Luminosity | 2.111 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 5.000 Gyr |
| Apparent Magnitude | V: 10.424 · G: 10.380 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.053620 AU |
| Orbital Period | 4.353 days |
| Mean Orbital Velocity | 134 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 85.4300° |
| Mean Bulk Density | 0.25 g/cm³ (32.4 km/s vesc) |
| Insolation Flux | 617.3090 S⊕ (~840,158 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 742.100 LY (227.537 pc) |