WASP-105 b

Astrophysical Synthesis & Habitability Characterization

WASP-105 b is a confirmed gas giant exoplanet orbiting the star WASP-105, located approximately 552.1 light-years (169.27 parsecs) from the Solar System. First announced in 2017 by SuperWASP-South using the Transit detection technique (producing an estimated primary transit depth of 1.2016% across the stellar disk), this world measures 10.761 Earth radii (0.96 Jupiter radii) and has a measured mass of 572.094 Earth masses (1.8 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.53 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 4.94 g⊕ (48.44 m/s²), and an escape velocity of 81.6 km/s.

In its orbital architecture around WASP-105, WASP-105 b completes one full revolution every 7.873 Earth days at a semi-major axis of 0.075 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 103.6 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 900 K (+627°C / +1161°F) and receiving 166.54 S⊕ (~226,657 W/m²), WASP-105 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star WASP-105 is classified as an orange K-type star of spectral type K2 with an effective photospheric temperature of 5,070 K, a radius of 0.9 R☉, a mass of 0.89 M☉, an estimated bolometric luminosity of 0.48 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.28 dex (metal-rich relative to the Sun). From Earth, WASP-105 shines at apparent V-band magnitude 12.049 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere.

Discovery Facility: SuperWASP-South · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).