Kepler-788 b

Astrophysical Synthesis & Habitability Characterization

Kepler-788 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-788, located approximately 5791.9 light-years (1775.8 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0361% across the stellar disk), this world measures 2.55 Earth radii and has a measured mass of 7.04 Earth masses. Combining its mass and radius yields a mean bulk density of 2.34 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.08 g⊕ (10.59 m/s²), and an escape velocity of 18.6 km/s.

In its orbital architecture around Kepler-788, Kepler-788 b completes one full revolution every 8.398 Earth days at a semi-major axis of 0.0835 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 108.2 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 984 K (+711°C / +1312°F) and receiving 357.19 S⊕ (~486,137 W/m²), Kepler-788 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-788 is classified as a stellar host with an effective photospheric temperature of 6,159 K, a radius of 1.23 R☉, a mass of 1.16 M☉, an estimated bolometric luminosity of 1.953 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.02 Gyr and a metallicity of [Fe/H] = 0.05 dex (near-solar heavy-element abundance). From Earth, Kepler-788 shines at apparent V-band magnitude 15.45 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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