Kepler-240 b
Astrophysical Synthesis & Habitability Characterization
Kepler-240 b is a confirmed super-earth exoplanet orbiting the star Kepler-240, located approximately 2436.1 light-years (746.93 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0289% across the stellar disk), this world measures 1.37 Earth radii and has a measured mass of 2.45 Earth masses. Combining its mass and radius yields a mean bulk density of 5.25 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.31 g⊕ (12.85 m/s²), and an escape velocity of 15 km/s.
In its orbital architecture around Kepler-240, Kepler-240 b completes one full revolution every 4.144 Earth days at a semi-major axis of 0.048 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 126 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 864 K (+591°C / +1096°F) and receiving 142.74 S⊕ (~194,264 W/m²), Kepler-240 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-240 is classified as a stellar host with an effective photospheric temperature of 4,985 K, a radius of 0.739 R☉, a mass of 0.868 M☉, an estimated bolometric luminosity of 0.303 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.91 Gyr and a metallicity of [Fe/H] = 0.41 dex (metal-rich relative to the Sun). From Earth, Kepler-240 shines at apparent V-band magnitude 15.953 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-240 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-240 b sharing its stellar neighborhood alongside Kepler-240 c.
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-240 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,985 K |
| Stellar Radius | 0.7390 R☉ |
| Stellar Mass | 0.8680 M☉ |
| Bolometric Luminosity | 0.303 L☉ |
| Metallicity [Fe/H] | 0.410 dex |
| Stellar Age | 1.910 Gyr |
| Apparent Magnitude | V: 15.953 · G: 15.662 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.048000 AU |
| Orbital Period | 4.144 days |
| Mean Orbital Velocity | 126 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.9900° |
| Mean Bulk Density | 5.25 g/cm³ (15 km/s vesc) |
| Insolation Flux | 142.7360 S⊕ (~194,264 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2436.100 LY (746.927 pc) |