WASP-75 b
Astrophysical Synthesis & Habitability Characterization
WASP-75 b is a confirmed gas giant exoplanet orbiting the star WASP-75, located approximately 958.9 light-years (294 parsecs) from the Solar System. First announced in 2013 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.0728% across the stellar disk), this world measures 14.235 Earth radii (1.27 Jupiter radii) and has a measured mass of 340.06 Earth masses (1.07 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.65 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.68 g⊕ (16.48 m/s²), and an escape velocity of 54.7 km/s.
In its orbital architecture around WASP-75, WASP-75 b completes one full revolution every 2.484 Earth days at a semi-major axis of 0.0375 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 164.2 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 1710 K (+1437°C / +2619°F) and receiving 1,657.00 S⊕ (~2,255,177 W/m²), WASP-75 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-75 is classified as a warm F-type star of spectral type F9 with an effective photospheric temperature of 6,100 K, a radius of 1.26 R☉, a mass of 1.14 M☉, an estimated bolometric luminosity of 1.972 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.5 Gyr and a metallicity of [Fe/H] = 0.07 dex (metal-rich relative to the Sun). From Earth, WASP-75 shines at apparent V-band magnitude 11.591 (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-75 |
| Spectral Type | F9 |
| Effective Temp (Teff) | 6,100 K |
| Stellar Radius | 1.2600 R☉ |
| Stellar Mass | 1.1400 M☉ |
| Bolometric Luminosity | 1.972 L☉ |
| Metallicity [Fe/H] | 0.070 dex |
| Stellar Age | 3.500 Gyr |
| Apparent Magnitude | V: 11.591 · G: 11.335 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.037500 AU |
| Orbital Period | 2.484 days |
| Mean Orbital Velocity | 164.2 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 82.0000° |
| Mean Bulk Density | 0.65 g/cm³ (54.7 km/s vesc) |
| Insolation Flux | 1657.0000 S⊕ (~2,255,177 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 958.900 LY (294.001 pc) |