Kepler-700 b

Astrophysical Synthesis & Habitability Characterization

Kepler-700 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-700, located approximately 4865.5 light-years (1491.76 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.3272% across the stellar disk), this world measures 5.99 Earth radii (0.53 Jupiter radii) and has a measured mass of 30 Earth masses (0.09 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.77 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.84 g⊕ (8.24 m/s²), and an escape velocity of 25 km/s.

In its orbital architecture around Kepler-700, Kepler-700 b completes one full revolution every 80.872 Earth days at a semi-major axis of 0.3577 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 48.1 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 452 K (+179°C / +354°F) and receiving 12.07 S⊕ (~16,429 W/m²), Kepler-700 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-700 is classified as a stellar host with an effective photospheric temperature of 5,692 K, a radius of 0.96 R☉, a mass of 0.98 M☉, an estimated bolometric luminosity of 0.868 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.37 Gyr and a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-700 shines at apparent V-band magnitude 15.202 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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