HATS-50 b

Astrophysical Synthesis & Habitability Characterization

HATS-50 b is a confirmed gas giant exoplanet orbiting the star HATS-50, located approximately 2468.2 light-years (756.74 parsecs) from the Solar System. First announced in 2017 by HATSouth using the Transit detection technique (producing an estimated primary transit depth of 1.0807% across the stellar disk), this world measures 12.666 Earth radii (1.13 Jupiter radii) and has a measured mass of 123.954 Earth masses (0.39 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.34 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.77 g⊕ (7.55 m/s²), and an escape velocity of 35 km/s.

In its orbital architecture around HATS-50, HATS-50 b completes one full revolution every 3.83 Earth days at a semi-major axis of 0.05046 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 143.3 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.516, swinging from 0.0244 AU at periapsis out to 0.0765 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.

⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1275 K (+1002°C / +1836°F) and receiving 625.30 S⊕ (~851,036 W/m²), HATS-50 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star HATS-50 is classified as a stellar host with an effective photospheric temperature of 5,990 K, a radius of 1.117 R☉, a mass of 1.168 M☉, an estimated bolometric luminosity of 1.441 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.2 Gyr. From Earth, HATS-50 shines at apparent V-band magnitude 14.045 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere.

Discovery Facility: HATSouth · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).