Kepler-1535 b

Astrophysical Synthesis & Habitability Characterization

Kepler-1535 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1535, located approximately 2928 light-years (897.73 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0444% across the stellar disk), this world measures 2.55 Earth radii and has a measured mass of 7.04 Earth masses. Combining its mass and radius yields a mean bulk density of 2.34 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.08 g⊕ (10.59 m/s²), and an escape velocity of 18.6 km/s.

In its orbital architecture around Kepler-1535, Kepler-1535 b completes one full revolution every 138.944 Earth days at a semi-major axis of 0.5329 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 41.7 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 384 K (+111°C / +232°F) and receiving 5.38 S⊕ (~7,328 W/m²), Kepler-1535 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star Kepler-1535 is classified as a stellar host with an effective photospheric temperature of 6,021 K, a radius of 1.11 R☉, a mass of 1.08 M☉, an estimated bolometric luminosity of 1.453 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.47 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, Kepler-1535 shines at apparent V-band magnitude 14.385 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.

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