WASP-154 b
Astrophysical Synthesis & Habitability Characterization
WASP-154 b is a confirmed gas giant exoplanet orbiting the star WASP-154, located approximately 702.9 light-years (215.5 parsecs) from the Solar System. First announced in 2025 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.437% across the stellar disk), this world measures 10.761 Earth radii (0.96 Jupiter radii) and has a measured mass of 198.961 Earth masses (0.63 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.88 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.72 g⊕ (16.87 m/s²), and an escape velocity of 48.1 km/s.
In its orbital architecture around WASP-154, WASP-154 b completes one full revolution every 3.812 Earth days at a semi-major axis of 0.044 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 125.6 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 994 K (+721°C / +1330°F) and receiving 162.00 S⊕ (~220,482 W/m²), WASP-154 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-154 is classified as a stellar host with an effective photospheric temperature of 4,774 K, a radius of 0.823 R☉, a mass of 0.8 M☉, an estimated bolometric luminosity of 0.316 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.2 dex (metal-rich relative to the Sun). From Earth, WASP-154 shines at apparent V-band magnitude 13.191 (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-154 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,774 K |
| Stellar Radius | 0.8230 R☉ |
| Stellar Mass | 0.8000 M☉ |
| Bolometric Luminosity | 0.316 L☉ |
| Metallicity [Fe/H] | 0.200 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 13.191 · G: 12.834 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.044000 AU |
| Orbital Period | 3.812 days |
| Mean Orbital Velocity | 125.6 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 88.4600° |
| Mean Bulk Density | 0.88 g/cm³ (48.1 km/s vesc) |
| Insolation Flux | 162.0000 S⊕ (~220,482 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 702.900 LY (215.501 pc) |