Kepler-1276 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1276 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1276, located approximately 1756.3 light-years (538.48 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0081% across the stellar disk), this world measures 1.19 Earth radii and has a measured mass of 1.81 Earth masses. Combining its mass and radius yields a mean bulk density of 5.92 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.28 g⊕ (12.55 m/s²), and an escape velocity of 13.8 km/s.
In its orbital architecture around Kepler-1276, Kepler-1276 b completes one full revolution every 12.572 Earth days at a semi-major axis of 0.10863 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 94 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 886 K (+613°C / +1135°F) and receiving 139.77 S⊕ (~190,227 W/m²), Kepler-1276 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1276 is classified as a stellar host with an effective photospheric temperature of 6,188 K, a radius of 1.21 R☉, a mass of 1.14 M☉, an estimated bolometric luminosity of 1.926 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.09 Gyr and a metallicity of [Fe/H] = -0.02 dex (near-solar heavy-element abundance). From Earth, Kepler-1276 shines at apparent V-band magnitude 12.992 (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-1276 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,188 K |
| Stellar Radius | 1.2100 R☉ |
| Stellar Mass | 1.1400 M☉ |
| Bolometric Luminosity | 1.926 L☉ |
| Metallicity [Fe/H] | -0.020 dex |
| Stellar Age | 3.090 Gyr |
| Apparent Magnitude | V: 12.992 · G: 12.849 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.108630 AU |
| Orbital Period | 12.572 days |
| Mean Orbital Velocity | 94 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.2700° |
| Mean Bulk Density | 5.92 g/cm³ (13.8 km/s vesc) |
| Insolation Flux | 139.7700 S⊕ (~190,227 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1756.300 LY (538.481 pc) |