Kepler-135 c
Astrophysical Synthesis & Habitability Characterization
Kepler-135 c is a confirmed terrestrial exoplanet orbiting the star Kepler-135, located approximately 2028.2 light-years (621.86 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.007% across the stellar disk), this world measures 1.16 Earth radii and has a measured mass of 1.65 Earth masses. Combining its mass and radius yields a mean bulk density of 5.83 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.23 g⊕ (12.06 m/s²), and an escape velocity of 13.3 km/s.
In its orbital architecture around Kepler-135, Kepler-135 c completes one full revolution every 11.449 Earth days at a semi-major axis of 0.103 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 97.9 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 975 K (+702°C / +1296°F) and receiving 209.97 S⊕ (~285,765 W/m²), Kepler-135 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-135 is classified as a stellar host with an effective photospheric temperature of 6,090 K, a radius of 1.275 R☉, a mass of 1.047 M☉, an estimated bolometric luminosity of 2.006 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.62 Gyr and a metallicity of [Fe/H] = -0.105 dex (metal-poor relative to the Sun). From Earth, Kepler-135 shines at apparent V-band magnitude 12.794 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-135 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-135 c sharing its stellar neighborhood alongside Kepler-135 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-135 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,090 K |
| Stellar Radius | 1.2750 R☉ |
| Stellar Mass | 1.0470 M☉ |
| Bolometric Luminosity | 2.006 L☉ |
| Metallicity [Fe/H] | -0.105 dex |
| Stellar Age | 2.620 Gyr |
| Apparent Magnitude | V: 12.794 · G: 12.679 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.103000 AU |
| Orbital Period | 11.449 days |
| Mean Orbital Velocity | 97.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 85.4200° |
| Mean Bulk Density | 5.83 g/cm³ (13.3 km/s vesc) |
| Insolation Flux | 209.9670 S⊕ (~285,765 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2028.200 LY (621.855 pc) |