Kepler-625 c
Astrophysical Synthesis & Habitability Characterization
Kepler-625 c is a confirmed terrestrial exoplanet orbiting the star Kepler-625, located approximately 2481.1 light-years (760.71 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0101% across the stellar disk), this world measures 1.05 Earth radii and has a measured mass of 1.16 Earth masses. Combining its mass and radius yields a mean bulk density of 5.53 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 11.8 km/s.
In its orbital architecture around Kepler-625, Kepler-625 c completes one full revolution every 4.165 Earth days at a semi-major axis of 0.05379 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 140.5 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 1048 K (+775°C / +1427°F) and receiving 932.13 S⊕ (~1,268,632 W/m²), Kepler-625 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-625 is classified as a stellar host with an effective photospheric temperature of 5,789 K, a radius of 0.96 R☉, a mass of 1.04 M☉, an estimated bolometric luminosity of 0.929 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.51 Gyr and a metallicity of [Fe/H] = 0.1 dex (metal-rich relative to the Sun). From Earth, Kepler-625 shines at apparent V-band magnitude 13.395 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-625 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-625 c sharing its stellar neighborhood alongside Kepler-625 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-625 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,789 K |
| Stellar Radius | 0.9600 R☉ |
| Stellar Mass | 1.0400 M☉ |
| Bolometric Luminosity | 0.929 L☉ |
| Metallicity [Fe/H] | 0.100 dex |
| Stellar Age | 1.510 Gyr |
| Apparent Magnitude | V: 13.395 · G: 13.264 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.053790 AU |
| Orbital Period | 4.165 days |
| Mean Orbital Velocity | 140.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 87.8300° |
| Mean Bulk Density | 5.53 g/cm³ (11.8 km/s vesc) |
| Insolation Flux | 932.1320 S⊕ (~1,268,632 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2481.100 LY (760.708 pc) |