Kepler-913 c
Astrophysical Synthesis & Habitability Characterization
Kepler-913 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-913, located approximately 3234.2 light-years (991.62 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0387% across the stellar disk), this world measures 3.858 Earth radii (0.34 Jupiter radii) and has a measured mass of 14.2 Earth masses. Combining its mass and radius yields a mean bulk density of 1.36 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.95 g⊕ (9.32 m/s²), and an escape velocity of 21.5 km/s.
In its orbital architecture around Kepler-913, Kepler-913 c completes one full revolution every 5.939 Earth days at a semi-major axis of 0.0699 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 128 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 1357 K (+1084°C / +1983°F) and receiving 122.82 S⊕ (~167,158 W/m²), Kepler-913 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-913 is classified as a stellar host with an effective photospheric temperature of 6,068 K, a radius of 1.797 R☉, a mass of 1.294 M☉, an estimated bolometric luminosity of 3.928 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.62 Gyr and a metallicity of [Fe/H] = 0.16 dex (metal-rich relative to the Sun). From Earth, Kepler-913 shines at apparent V-band magnitude 15.522 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-913 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-913 c sharing its stellar neighborhood alongside Kepler-913 b.
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-913 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,068 K |
| Stellar Radius | 1.7970 R☉ |
| Stellar Mass | 1.2940 M☉ |
| Bolometric Luminosity | 3.928 L☉ |
| Metallicity [Fe/H] | 0.160 dex |
| Stellar Age | 5.620 Gyr |
| Apparent Magnitude | V: 15.522 · G: 15.739 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.069900 AU |
| Orbital Period | 5.939 days |
| Mean Orbital Velocity | 128 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.7000° |
| Mean Bulk Density | 1.36 g/cm³ (21.5 km/s vesc) |
| Insolation Flux | 122.8200 S⊕ (~167,158 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3234.200 LY (991.618 pc) |