Kepler-1265 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1265 b is a confirmed super-earth exoplanet orbiting the star Kepler-1265, located approximately 1903.6 light-years (583.64 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0322% across the stellar disk), this world measures 1.35 Earth radii and has a measured mass of 2.39 Earth masses. Combining its mass and radius yields a mean bulk density of 5.36 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.31 g⊕ (12.85 m/s²), and an escape velocity of 14.9 km/s.

In its orbital architecture around Kepler-1265, Kepler-1265 b completes one full revolution every 6.494 Earth days at a semi-major axis of 0.0612 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 102.5 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 732 K (+459°C / +858°F) and receiving 58.15 S⊕ (~79,142 W/m²), Kepler-1265 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1265 is classified as a stellar host with an effective photospheric temperature of 4,630 K, a radius of 0.69 R☉, a mass of 0.71 M☉, an estimated bolometric luminosity of 0.196 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.25 Gyr and a metallicity of [Fe/H] = -0.1 dex (near-solar heavy-element abundance). From Earth, Kepler-1265 shines at apparent V-band magnitude 16.024 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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