WASP-25 b
Astrophysical Synthesis & Habitability Characterization
WASP-25 b is a confirmed gas giant exoplanet orbiting the star WASP-25, located approximately 689.5 light-years (211.42 parsecs) from the Solar System. First announced in 2010 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 2.051% across the stellar disk), this world measures 13.809 Earth radii (1.23 Jupiter radii) and has a measured mass of 179.255 Earth masses (0.56 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.38 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.94 g⊕ (9.22 m/s²), and an escape velocity of 40.3 km/s.
In its orbital architecture around WASP-25, WASP-25 b completes one full revolution every 3.765 Earth days at a semi-major axis of 0.0473 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 136.7 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 1217 K (+944°C / +1731°F) and receiving 341.00 S⊕ (~464,101 W/m²), WASP-25 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-25 is classified as a stellar host with an effective photospheric temperature of 5,697 K, a radius of 0.884 R☉, a mass of 0.962 M☉, an estimated bolometric luminosity of 0.739 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.9 Gyr and a metallicity of [Fe/H] = -0.2 dex (metal-poor relative to the Sun). From Earth, WASP-25 shines at apparent V-band magnitude 11.875 (faint and requiring research-grade or CCD telescopic photometry) in the Southern 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-25 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,697 K |
| Stellar Radius | 0.8840 R☉ |
| Stellar Mass | 0.9620 M☉ |
| Bolometric Luminosity | 0.739 L☉ |
| Metallicity [Fe/H] | -0.200 dex |
| Stellar Age | 1.900 Gyr |
| Apparent Magnitude | V: 11.875 · G: 11.689 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.047300 AU |
| Orbital Period | 3.765 days |
| Mean Orbital Velocity | 136.7 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 88.1900° |
| Mean Bulk Density | 0.38 g/cm³ (40.3 km/s vesc) |
| Insolation Flux | 341.0000 S⊕ (~464,101 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 689.500 LY (211.416 pc) |