WASP-74 b
Astrophysical Synthesis & Habitability Characterization
WASP-74 b is a confirmed gas giant exoplanet orbiting the star WASP-74, located approximately 486.7 light-years (149.22 parsecs) from the Solar System. First announced in 2015 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 0.9686% across the stellar disk), this world measures 15.244 Earth radii (1.36 Jupiter radii) and has a measured mass of 228.838 Earth masses (0.72 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.36 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.98 g⊕ (9.61 m/s²), and an escape velocity of 43.3 km/s.
In its orbital architecture around WASP-74, WASP-74 b completes one full revolution every 2.138 Earth days at a semi-major axis of 0.03443 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 175.2 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 1865 K (+1592°C / +2898°F) and receiving 531.16 S⊕ (~722,907 W/m²), WASP-74 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-74 is classified as a warm F-type star of spectral type F9 with an effective photospheric temperature of 5,990 K, a radius of 1.42 R☉, a mass of 0.98 M☉, an estimated bolometric luminosity of 2.329 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.49 Gyr and a metallicity of [Fe/H] = 0.39 dex (metal-rich relative to the Sun). From Earth, WASP-74 shines at apparent V-band magnitude 9.75 (accessible to binoculars and small amateur telescopes) 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-74 |
| Spectral Type | F9 |
| Effective Temp (Teff) | 5,990 K |
| Stellar Radius | 1.4200 R☉ |
| Stellar Mass | 0.9800 M☉ |
| Bolometric Luminosity | 2.329 L☉ |
| Metallicity [Fe/H] | 0.390 dex |
| Stellar Age | 3.490 Gyr |
| Apparent Magnitude | V: 9.750 · G: 9.572 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.034430 AU |
| Orbital Period | 2.138 days |
| Mean Orbital Velocity | 175.2 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 79.8100° |
| Mean Bulk Density | 0.36 g/cm³ (43.3 km/s vesc) |
| Insolation Flux | 531.1590 S⊕ (~722,907 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 486.700 LY (149.216 pc) |