Kepler-10 c
Astrophysical Synthesis & Habitability Characterization
Kepler-10 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-10, located approximately 605 light-years (185.51 parsecs) from the Solar System. First announced in 2011 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0411% across the stellar disk), this world measures 2.355 Earth radii and has a measured mass of 11.29 Earth masses. Combining its mass and radius yields a mean bulk density of 4.77 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 2.04 g⊕ (20.01 m/s²), and an escape velocity of 24.5 km/s.
In its orbital architecture around Kepler-10, Kepler-10 c completes one full revolution every 45.294 Earth days at a semi-major axis of 0.241 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 57.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.136 carries the world between 0.2082 AU at periapsis and 0.2738 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 579 K (+306°C / +583°F) and receiving 18.30 S⊕ (~24,906 W/m²), Kepler-10 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-10 is classified as a stellar host with an effective photospheric temperature of 5,708 K, a radius of 1.065 R☉, a mass of 0.91 M☉, an estimated bolometric luminosity of 1.08 L☉. Stellar evolution modeling indicates an estimated stellar age of 10.6 Gyr and a metallicity of [Fe/H] = -0.15 dex (metal-poor relative to the Sun). From Earth, Kepler-10 shines at apparent V-band magnitude 11.043 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-10 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-10 c sharing its stellar neighborhood alongside Kepler-10 b, Kepler-10 d.
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-10 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,708 K |
| Stellar Radius | 1.0650 R☉ |
| Stellar Mass | 0.9100 M☉ |
| Bolometric Luminosity | 1.08 L☉ |
| Metallicity [Fe/H] | -0.150 dex |
| Stellar Age | 10.600 Gyr |
| Apparent Magnitude | V: 11.043 · G: 10.919 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.241000 AU |
| Orbital Period | 45.294 days |
| Mean Orbital Velocity | 57.9 km/s |
| Orbital Eccentricity (e) | 0.13600 |
| Orbital Inclination (i) | 89.6230° |
| Mean Bulk Density | 4.77 g/cm³ (24.5 km/s vesc) |
| Insolation Flux | 18.3000 S⊕ (~24,906 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 605.000 LY (185.506 pc) |