Kepler-1126 c
Astrophysical Synthesis & Habitability Characterization
Kepler-1126 c is a confirmed super-earth exoplanet orbiting the star Kepler-1126, located approximately 2073.5 light-years (635.74 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0208% across the stellar disk), this world measures 1.45 Earth radii and has a measured mass of 2.7 Earth masses. Combining its mass and radius yields a mean bulk density of 4.88 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.28 g⊕ (12.55 m/s²), and an escape velocity of 15.3 km/s.
In its orbital architecture around Kepler-1126, Kepler-1126 c completes one full revolution every 199.669 Earth days at a semi-major axis of 0.6193 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 33.7 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.
✓ Classified as a Temperate Habitable Zone Candidate.
With an estimated equilibrium temperature of 305 K (+32°C / +90°F) and an incident stellar irradiance of 2.06 S⊕ (~2,804 W/m²), Kepler-1126 c orbits within the empirical circumstellar habitable zone where a rocky surface under sufficient atmospheric pressure can maintain liquid surface water.
The host star Kepler-1126 is classified as a stellar host with an effective photospheric temperature of 5,678 K, a radius of 0.921 R☉, a mass of 0.794 M☉, an estimated bolometric luminosity of 0.791 L☉. Stellar evolution modeling indicates an estimated stellar age of 12.3 Gyr and a metallicity of [Fe/H] = -0.4 dex (metal-poor relative to the Sun). From Earth, Kepler-1126 shines at apparent V-band magnitude 14.221 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-1126 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-1126 c sharing its stellar neighborhood alongside Kepler-1126 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-1126 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,678 K |
| Stellar Radius | 0.9210 R☉ |
| Stellar Mass | 0.7940 M☉ |
| Bolometric Luminosity | 0.791 L☉ |
| Metallicity [Fe/H] | -0.400 dex |
| Stellar Age | 12.300 Gyr |
| Apparent Magnitude | V: 14.221 · G: 14.021 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.619300 AU |
| Orbital Period | 199.669 days |
| Mean Orbital Velocity | 33.7 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.9800° |
| Mean Bulk Density | 4.88 g/cm³ (15.3 km/s vesc) |
| Insolation Flux | 2.0600 S⊕ (~2,804 W/m²) |
| Habitable Zone Status | ★ Temperate Zone |
| Celestial Distance | 2073.500 LY (635.736 pc) |