Kepler-693 b

Astrophysical Synthesis & Habitability Characterization

Kepler-693 b is a confirmed gas giant exoplanet orbiting the star Kepler-693, located approximately 3755.7 light-years (1151.51 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 1.6802% across the stellar disk), this world measures 10.18 Earth radii (0.91 Jupiter radii) and has a measured mass of 73.8 Earth masses (0.23 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.39 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.71 g⊕ (6.96 m/s²), and an escape velocity of 30.1 km/s.

In its orbital architecture around Kepler-693, Kepler-693 b completes one full revolution every 15.376 Earth days at a semi-major axis of 0.1121 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 79.3 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 600 K (+327°C / +621°F) and receiving 31.64 S⊕ (~43,063 W/m²), Kepler-693 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-693 is classified as a stellar host with an effective photospheric temperature of 4,881 K, a radius of 0.72 R☉, a mass of 0.76 M☉, an estimated bolometric luminosity of 0.264 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.47 Gyr and a metallicity of [Fe/H] = -0.1 dex (near-solar heavy-element abundance). From Earth, Kepler-693 shines at apparent V-band magnitude 16.729 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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