WASP-11 b
Astrophysical Synthesis & Habitability Characterization
WASP-11 b is a confirmed gas giant exoplanet orbiting the star WASP-11, located approximately 406.8 light-years (124.73 parsecs) from the Solar System. First announced in 2008 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.6426% across the stellar disk), this world measures 12.442 Earth radii (1.11 Jupiter radii) and has a measured mass of 251.086 Earth masses (0.79 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.72 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.62 g⊕ (15.89 m/s²), and an escape velocity of 50.3 km/s.
In its orbital architecture around WASP-11, WASP-11 b completes one full revolution every 3.722 Earth days at a semi-major axis of 0.0435 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 127.1 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 992 K (+719°C / +1326°F) and receiving 184.99 S⊕ (~251,769 W/m²), WASP-11 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-11 is classified as an orange K-type star of spectral type K3 V with an effective photospheric temperature of 4,800 K, a radius of 0.89 R☉, a mass of 1.42 M☉, an estimated bolometric luminosity of 0.377 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.6 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, WASP-11 shines at apparent V-band magnitude 11.567 (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-11 |
| Spectral Type | K3 V |
| Effective Temp (Teff) | 4,800 K |
| Stellar Radius | 0.8900 R☉ |
| Stellar Mass | 1.4200 M☉ |
| Bolometric Luminosity | 0.377 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 7.600 Gyr |
| Apparent Magnitude | V: 11.567 · G: 11.554 |
| System Architecture | 3 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.043500 AU |
| Orbital Period | 3.722 days |
| Mean Orbital Velocity | 127.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.8000° |
| Mean Bulk Density | 0.72 g/cm³ (50.3 km/s vesc) |
| Insolation Flux | 184.9880 S⊕ (~251,769 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 406.800 LY (124.730 pc) |