Kepler-1285 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1285 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1285, located approximately 1377.3 light-years (422.27 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0048% across the stellar disk), this world measures 0.97 Earth radii and has a measured mass of 0.871 Earth masses. Combining its mass and radius yields a mean bulk density of 5.26 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 0.93 g⊕ (9.12 m/s²), and an escape velocity of 10.6 km/s.

In its orbital architecture around Kepler-1285, Kepler-1285 b completes one full revolution every 14.797 Earth days at a semi-major axis of 0.12758 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 93.8 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 874 K (+601°C / +1114°F) and receiving 181.59 S⊕ (~247,145 W/m²), Kepler-1285 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1285 is classified as a stellar host with an effective photospheric temperature of 6,170 K, a radius of 1.28 R☉, a mass of 1.2 M☉, an estimated bolometric luminosity of 2.13 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.75 Gyr and a metallicity of [Fe/H] = 0.16 dex (metal-rich relative to the Sun). From Earth, Kepler-1285 shines at apparent V-band magnitude 11.717 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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