WASP-104 b
Astrophysical Synthesis & Habitability Characterization
WASP-104 b is a confirmed gas giant exoplanet orbiting the star WASP-104, located approximately 606.4 light-years (185.93 parsecs) from the Solar System. First announced in 2014 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.4722% across the stellar disk), this world measures 12.745 Earth radii (1.14 Jupiter radii) and has a measured mass of 404.263 Earth masses (1.27 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.08 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 2.49 g⊕ (24.42 m/s²), and an escape velocity of 63 km/s.
In its orbital architecture around WASP-104, WASP-104 b completes one full revolution every 1.755 Earth days at a semi-major axis of 0.02918 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 180.8 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 1516 K (+1243°C / +2269°F) and receiving 867.74 S⊕ (~1,180,989 W/m²), WASP-104 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-104 is classified as a solar-type yellow star of spectral type G8 with an effective photospheric temperature of 5,475 K, a radius of 0.963 R☉, a mass of 1.076 M☉, an estimated bolometric luminosity of 0.748 L☉. Stellar evolution modeling indicates an estimated stellar age of 3 Gyr and a metallicity of [Fe/H] = 0.32 dex (metal-rich relative to the Sun). From Earth, WASP-104 shines at apparent V-band magnitude 11.779 (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-104 |
| Spectral Type | G8 |
| Effective Temp (Teff) | 5,475 K |
| Stellar Radius | 0.9630 R☉ |
| Stellar Mass | 1.0760 M☉ |
| Bolometric Luminosity | 0.748 L☉ |
| Metallicity [Fe/H] | 0.320 dex |
| Stellar Age | 3.000 Gyr |
| Apparent Magnitude | V: 11.779 · G: 11.593 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.029180 AU |
| Orbital Period | 1.755 days |
| Mean Orbital Velocity | 180.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.6300° |
| Mean Bulk Density | 1.08 g/cm³ (63 km/s vesc) |
| Insolation Flux | 867.7365 S⊕ (~1,180,989 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 606.400 LY (185.932 pc) |