Kepler-779 b

Astrophysical Synthesis & Habitability Characterization

Kepler-779 b is a confirmed terrestrial exoplanet orbiting the star Kepler-779, located approximately 923.5 light-years (283.16 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0367% across the stellar disk), this world measures 0.92 Earth radii and has a measured mass of 0.721 Earth masses. Combining its mass and radius yields a mean bulk density of 5.11 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 0.85 g⊕ (8.34 m/s²), and an escape velocity of 9.9 km/s.

In its orbital architecture around Kepler-779, Kepler-779 b completes one full revolution every 7.097 Earth days at a semi-major axis of 0.0533 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 81.7 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 425 K (+152°C / +306°F) and receiving 15.03 S⊕ (~20,453 W/m²), Kepler-779 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-779 is classified as a stellar host with an effective photospheric temperature of 3,804 K, a radius of 0.44 R☉, a mass of 0.46 M☉, an estimated bolometric luminosity of 0.036 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.89 Gyr and a metallicity of [Fe/H] = -0.43 dex (metal-poor relative to the Sun). From Earth, Kepler-779 shines at apparent V-band magnitude 16.303 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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