Kepler-1608 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1608 b is a confirmed super-earth exoplanet orbiting the star Kepler-1608, located approximately 2713.6 light-years (832 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0485% across the stellar disk), this world measures 1.73 Earth radii and has a measured mass of 3.64 Earth masses. Combining its mass and radius yields a mean bulk density of 3.88 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.22 g⊕ (11.96 m/s²), and an escape velocity of 16.2 km/s.

In its orbital architecture around Kepler-1608, Kepler-1608 b completes one full revolution every 16.474 Earth days at a semi-major axis of 0.1126 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 74.4 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 612 K (+339°C / +642°F) and receiving 33.22 S⊕ (~45,212 W/m²), Kepler-1608 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1608 is classified as a stellar host with an effective photospheric temperature of 4,992 K, a radius of 0.72 R☉, a mass of 0.75 M☉, an estimated bolometric luminosity of 0.289 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.13 Gyr and a metallicity of [Fe/H] = -0.24 dex (metal-poor relative to the Sun). From Earth, Kepler-1608 shines at apparent V-band magnitude 16.265 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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