Kepler-718 b

Astrophysical Synthesis & Habitability Characterization

Kepler-718 b is a confirmed gas giant exoplanet orbiting the star Kepler-718, located approximately 4247.6 light-years (1302.33 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 1.3639% across the stellar disk), this world has a measured radius of 16.56 Earth radii (1.48 R♃), though radial-velocity mass constraints remain unmeasured in the current composite catalogue.

In its orbital architecture around Kepler-718, Kepler-718 b completes one full revolution every 2.052 Earth days at a semi-major axis of 0.0322 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 170.7 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 1497 K (+1224°C / +2235°F) and receiving 1,324.20 S⊕ (~1,802,236 W/m²), Kepler-718 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-718 is classified as a stellar host with an effective photospheric temperature of 6,191 K, a radius of 1.3 R☉, a mass of 1.18 M☉, an estimated bolometric luminosity of 2.228 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.57 Gyr and a metallicity of [Fe/H] = 0.06 dex (metal-rich relative to the Sun). From Earth, Kepler-718 shines at apparent V-band magnitude 15.399 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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