Kepler-1765 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1765 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1765, located approximately 2493.3 light-years (764.46 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0462% across the stellar disk), this world measures 2.495 Earth radii and has a measured mass of 6.78 Earth masses. Combining its mass and radius yields a mean bulk density of 2.41 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.09 g⊕ (10.69 m/s²), and an escape velocity of 18.4 km/s.

In its orbital architecture around Kepler-1765, Kepler-1765 b completes one full revolution every 10.419 Earth days at a semi-major axis of 0.0917 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 95.8 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 855 K (+582°C / +1080°F) and receiving 126.48 S⊕ (~172,139 W/m²), Kepler-1765 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1765 is classified as a stellar host with an effective photospheric temperature of 5,692 K, a radius of 1.064 R☉, a mass of 0.946 M☉, an estimated bolometric luminosity of 1.066 L☉. Stellar evolution modeling indicates an estimated stellar age of 11.9 Gyr and a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-1765 shines at apparent V-band magnitude 15.04 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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