Kepler-1515 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1515 b is a confirmed gas giant exoplanet orbiting the star Kepler-1515, located approximately 1759 light-years (539.32 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.3856% across the stellar disk), this world measures 9.55 Earth radii (0.85 Jupiter radii) and has a measured mass of 66.2 Earth masses (0.21 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.42 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.73 g⊕ (7.16 m/s²), and an escape velocity of 29.5 km/s.

In its orbital architecture around Kepler-1515, Kepler-1515 b completes one full revolution every 214.311 Earth days at a semi-major axis of 0.75235 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 38.2 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 380 K (+107°C / +225°F) and receiving 6.02 S⊕ (~8,189 W/m²), Kepler-1515 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1515 is classified as a stellar host with an effective photospheric temperature of 6,511 K, a radius of 1.41 R☉, a mass of 1.3 M☉, an estimated bolometric luminosity of 3.206 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.82 Gyr and a metallicity of [Fe/H] = 0.07 dex (metal-rich relative to the Sun). From Earth, Kepler-1515 shines at apparent V-band magnitude 12.1 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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