Kepler-1004 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1004 b is a confirmed gas giant exoplanet orbiting the star Kepler-1004, located approximately 3759.5 light-years (1152.68 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0288% across the stellar disk), this world measures 6.28 Earth radii (0.56 Jupiter radii) and has a measured mass of 32.5 Earth masses (0.1 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.72 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.82 g⊕ (8.04 m/s²), and an escape velocity of 25.4 km/s.

In its orbital architecture around Kepler-1004, Kepler-1004 b completes one full revolution every 5.288 Earth days at a semi-major axis of 0.06791 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 139.7 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 1661 K (+1388°C / +2530°F) and receiving 1,610.09 S⊕ (~2,191,328 W/m²), Kepler-1004 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1004 is classified as a stellar host with an effective photospheric temperature of 4,972 K, a radius of 3.39 R☉, a mass of 1.11 M☉, an estimated bolometric luminosity of 6.301 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.76 Gyr and a metallicity of [Fe/H] = -0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-1004 shines at apparent V-band magnitude 13.705 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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