WASP-197 b
Astrophysical Synthesis & Habitability Characterization
WASP-197 b is a confirmed gas giant exoplanet orbiting the star WASP-197, located approximately 1577.5 light-years (483.68 parsecs) from the Solar System. First announced in 2025 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 0.3933% across the stellar disk), this world measures 14.448 Earth radii (1.29 Jupiter radii) and has a measured mass of 403.324 Earth masses (1.27 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.74 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.93 g⊕ (18.93 m/s²), and an escape velocity of 59.1 km/s.
In its orbital architecture around WASP-197, WASP-197 b completes one full revolution every 5.167 Earth days at a semi-major axis of 0.065 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 136.9 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 1665 K (+1392°C / +2538°F) and receiving 1,276.00 S⊕ (~1,736,636 W/m²), WASP-197 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-197 is classified as a stellar host with an effective photospheric temperature of 6,050 K, a radius of 2.112 R☉, a mass of 1.36 M☉, an estimated bolometric luminosity of 5.362 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.6 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, WASP-197 shines at apparent V-band magnitude 11.565 (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-197 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,050 K |
| Stellar Radius | 2.1120 R☉ |
| Stellar Mass | 1.3600 M☉ |
| Bolometric Luminosity | 5.362 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 2.600 Gyr |
| Apparent Magnitude | V: 11.565 · G: 11.237 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.065000 AU |
| Orbital Period | 5.167 days |
| Mean Orbital Velocity | 136.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.2900° |
| Mean Bulk Density | 0.74 g/cm³ (59.1 km/s vesc) |
| Insolation Flux | 1276.0000 S⊕ (~1,736,636 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1577.500 LY (483.675 pc) |