Kepler-662 b

Astrophysical Synthesis & Habitability Characterization

Kepler-662 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-662, located approximately 2660.2 light-years (815.64 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0729% across the stellar disk), this world measures 2.18 Earth radii and has a measured mass of 5.39 Earth masses. Combining its mass and radius yields a mean bulk density of 2.87 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.13 g⊕ (11.08 m/s²), and an escape velocity of 17.6 km/s.

In its orbital architecture around Kepler-662, Kepler-662 b completes one full revolution every 21.677 Earth days at a semi-major axis of 0.1408 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 70.7 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 530 K (+257°C / +495°F) and receiving 23.82 S⊕ (~32,424 W/m²), Kepler-662 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-662 is classified as a stellar host with an effective photospheric temperature of 4,897 K, a radius of 0.74 R☉, a mass of 0.79 M☉, an estimated bolometric luminosity of 0.283 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.63 Gyr and a metallicity of [Fe/H] = -0.03 dex (near-solar heavy-element abundance). From Earth, Kepler-662 shines at apparent V-band magnitude 15.598 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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