Kepler-76 b
Astrophysical Synthesis & Habitability Characterization
Kepler-76 b is a confirmed gas giant exoplanet orbiting the star Kepler-76, located approximately 2684.1 light-years (822.96 parsecs) from the Solar System. First announced in 2013 by Kepler using the Orbital Brightness Modulation detection technique, this world measures 15.244 Earth radii (1.36 Jupiter radii) and has a measured mass of 638.838 Earth masses (2.01 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.99 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 2.75 g⊕ (26.97 m/s²), and an escape velocity of 72.4 km/s.
In its orbital architecture around Kepler-76, Kepler-76 b completes one full revolution every 1.545 Earth days at a semi-major axis of 0.0274 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 192.9 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 2140 K (+1867°C / +3393°F) and receiving 3,583.67 S⊕ (~4,877,379 W/m²), Kepler-76 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-76 is classified as a warm F-type star of spectral type F with an effective photospheric temperature of 6,409 K, a radius of 1.32 R☉, a mass of 1.2 M☉, an estimated bolometric luminosity of 2.638 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.62 Gyr and a metallicity of [Fe/H] = -0.1 dex (near-solar heavy-element abundance). From Earth, Kepler-76 shines at apparent V-band magnitude 13.474 (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-76 |
| Spectral Type | F |
| Effective Temp (Teff) | 6,409 K |
| Stellar Radius | 1.3200 R☉ |
| Stellar Mass | 1.2000 M☉ |
| Bolometric Luminosity | 2.638 L☉ |
| Metallicity [Fe/H] | -0.100 dex |
| Stellar Age | 0.620 Gyr |
| Apparent Magnitude | V: 13.474 · G: 13.276 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.027400 AU |
| Orbital Period | 1.545 days |
| Mean Orbital Velocity | 192.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 77.5500° |
| Mean Bulk Density | 0.99 g/cm³ (72.4 km/s vesc) |
| Insolation Flux | 3583.6730 S⊕ (~4,877,379 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2684.100 LY (822.960 pc) |