Kepler-1240 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1240 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1240, located approximately 2812.1 light-years (862.19 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0121% across the stellar disk), this world measures 1.15 Earth radii and has a measured mass of 1.6 Earth masses. Combining its mass and radius yields a mean bulk density of 5.8 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.21 g⊕ (11.87 m/s²), and an escape velocity of 13.2 km/s.
In its orbital architecture around Kepler-1240, Kepler-1240 b completes one full revolution every 4.866 Earth days at a semi-major axis of 0.05791 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 129.5 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 1121 K (+848°C / +1558°F) and receiving 539.13 S⊕ (~733,755 W/m²), Kepler-1240 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1240 is classified as a stellar host with an effective photospheric temperature of 5,682 K, a radius of 0.96 R☉, a mass of 0.98 M☉, an estimated bolometric luminosity of 0.862 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.07 Gyr and a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, Kepler-1240 shines at apparent V-band magnitude 14.092 (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-1240 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,682 K |
| Stellar Radius | 0.9600 R☉ |
| Stellar Mass | 0.9800 M☉ |
| Bolometric Luminosity | 0.862 L☉ |
| Metallicity [Fe/H] | 0.040 dex |
| Stellar Age | 4.070 Gyr |
| Apparent Magnitude | V: 14.092 · G: 13.961 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.057910 AU |
| Orbital Period | 4.866 days |
| Mean Orbital Velocity | 129.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.3800° |
| Mean Bulk Density | 5.8 g/cm³ (13.2 km/s vesc) |
| Insolation Flux | 539.1290 S⊕ (~733,755 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2812.100 LY (862.186 pc) |