Kepler-756 b
Astrophysical Synthesis & Habitability Characterization
Kepler-756 b is a confirmed terrestrial exoplanet orbiting the star Kepler-756, located approximately 2778.8 light-years (852 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0169% across the stellar disk), this world measures 1.12 Earth radii and has a measured mass of 1.46 Earth masses. Combining its mass and radius yields a mean bulk density of 5.73 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.16 g⊕ (11.38 m/s²), and an escape velocity of 12.8 km/s.
In its orbital architecture around Kepler-756, Kepler-756 b completes one full revolution every 1.225 Earth days at a semi-major axis of 0.0219 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 194.5 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 1741 K (+1468°C / +2674°F) and receiving 2,174.33 S⊕ (~2,959,263 W/m²), Kepler-756 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-756 is classified as a stellar host with an effective photospheric temperature of 5,282 K, a radius of 0.79 R☉, a mass of 0.82 M☉, an estimated bolometric luminosity of 0.436 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.47 Gyr and a metallicity of [Fe/H] = -0.19 dex (metal-poor relative to the Sun). From Earth, Kepler-756 shines at apparent V-band magnitude 15.986 (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-756 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,282 K |
| Stellar Radius | 0.7900 R☉ |
| Stellar Mass | 0.8200 M☉ |
| Bolometric Luminosity | 0.436 L☉ |
| Metallicity [Fe/H] | -0.190 dex |
| Stellar Age | 4.470 Gyr |
| Apparent Magnitude | V: 15.986 · G: 15.391 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.021900 AU |
| Orbital Period | 1.225 days |
| Mean Orbital Velocity | 194.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.9400° |
| Mean Bulk Density | 5.73 g/cm³ (12.8 km/s vesc) |
| Insolation Flux | 2174.3300 S⊕ (~2,959,263 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2778.800 LY (852.000 pc) |