Kepler-576 b
Astrophysical Synthesis & Habitability Characterization
Kepler-576 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-576, located approximately 2014.2 light-years (617.55 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0955% across the stellar disk), this world measures 3.27 Earth radii (0.29 Jupiter radii) and has a measured mass of 10.7 Earth masses. Combining its mass and radius yields a mean bulk density of 1.69 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1 g⊕ (9.81 m/s²), and an escape velocity of 20.2 km/s.
In its orbital architecture around Kepler-576, Kepler-576 b completes one full revolution every 29.911 Earth days at a semi-major axis of 0.179 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 65.1 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 541 K (+268°C / +514°F) and receiving 16.82 S⊕ (~22,888 W/m²), Kepler-576 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-576 is classified as a stellar host with an effective photospheric temperature of 5,672 K, a radius of 0.97 R☉, a mass of 0.99 M☉, an estimated bolometric luminosity of 0.874 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.47 Gyr and a metallicity of [Fe/H] = 0.09 dex (metal-rich relative to the Sun). From Earth, Kepler-576 shines at apparent V-band magnitude 14.627 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-576 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,672 K |
| Stellar Radius | 0.9700 R☉ |
| Stellar Mass | 0.9900 M☉ |
| Bolometric Luminosity | 0.874 L☉ |
| Metallicity [Fe/H] | 0.090 dex |
| Stellar Age | 4.470 Gyr |
| Apparent Magnitude | V: 14.627 · G: 14.382 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.179000 AU |
| Orbital Period | 29.911 days |
| Mean Orbital Velocity | 65.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.9300° |
| Mean Bulk Density | 1.69 g/cm³ (20.2 km/s vesc) |
| Insolation Flux | 16.8170 S⊕ (~22,888 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2014.200 LY (617.550 pc) |