WASP-76 b
Astrophysical Synthesis & Habitability Characterization
WASP-76 b is a confirmed gas giant exoplanet orbiting the star WASP-76, located approximately 634.2 light-years (194.46 parsecs) from the Solar System. First announced in 2016 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.1771% across the stellar disk), this world measures 20.781 Earth radii (1.85 Jupiter radii) and has a measured mass of 284.139 Earth masses (0.89 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.17 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.66 g⊕ (6.47 m/s²), and an escape velocity of 41.4 km/s.
In its orbital architecture around WASP-76, WASP-76 b completes one full revolution every 1.81 Earth days at a semi-major axis of 0.033 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 198.4 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 2228 K (+1955°C / +3551°F) and receiving 4,104.00 S⊕ (~5,585,544 W/m²), WASP-76 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-76 is classified as a warm F-type star of spectral type F7 with an effective photospheric temperature of 6,329 K, a radius of 1.756 R☉, a mass of 1.458 M☉, an estimated bolometric luminosity of 4.439 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.816 Gyr and a metallicity of [Fe/H] = 0.366 dex (metal-rich relative to the Sun). From Earth, WASP-76 shines at apparent V-band magnitude 9.518 (accessible to binoculars and small amateur telescopes) 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-76 |
| Spectral Type | F7 |
| Effective Temp (Teff) | 6,329 K |
| Stellar Radius | 1.7560 R☉ |
| Stellar Mass | 1.4580 M☉ |
| Bolometric Luminosity | 4.439 L☉ |
| Metallicity [Fe/H] | 0.366 dex |
| Stellar Age | 1.816 Gyr |
| Apparent Magnitude | V: 9.518 · G: 9.395 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.033000 AU |
| Orbital Period | 1.81 days |
| Mean Orbital Velocity | 198.4 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.6230° |
| Mean Bulk Density | 0.17 g/cm³ (41.4 km/s vesc) |
| Insolation Flux | 4104.0000 S⊕ (~5,585,544 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 634.200 LY (194.459 pc) |