Kepler-74 b

Astrophysical Synthesis & Habitability Characterization

Kepler-74 b is a confirmed gas giant exoplanet orbiting the star Kepler-74, located approximately 3840.6 light-years (1177.55 parsecs) from the Solar System. First announced in 2013 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.7758% across the stellar disk), this world measures 10.76 Earth radii (0.96 Jupiter radii) and has a measured mass of 200.22 Earth masses (0.63 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.89 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.73 g⊕ (16.97 m/s²), and an escape velocity of 48.3 km/s.

In its orbital architecture around Kepler-74, Kepler-74 b completes one full revolution every 7.341 Earth days at a semi-major axis of 0.0781 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 115.7 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 1078 K (+805°C / +1481°F) and receiving 337.68 S⊕ (~459,585 W/m²), Kepler-74 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-74 is classified as a warm F-type star of spectral type F8 V with an effective photospheric temperature of 6,000 K, a radius of 1.12 R☉, a mass of 1.18 M☉, an estimated bolometric luminosity of 1.459 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.8 Gyr and a metallicity of [Fe/H] = 0.42 dex (metal-rich relative to the Sun). From Earth, Kepler-74 shines at apparent V-band magnitude 14.487 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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