Kepler-322 c
Astrophysical Synthesis & Habitability Characterization
Kepler-322 c is a confirmed super-earth exoplanet orbiting the star Kepler-322, located approximately 1306.2 light-years (400.48 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0296% across the stellar disk), this world measures 1.67 Earth radii and has a measured mass of 3.43 Earth masses. Combining its mass and radius yields a mean bulk density of 4.06 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 16 km/s.
In its orbital architecture around Kepler-322, Kepler-322 c completes one full revolution every 4.337 Earth days at a semi-major axis of 0.051 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 127.9 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 996 K (+723°C / +1333°F) and receiving 203.41 S⊕ (~276,836 W/m²), Kepler-322 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-322 is classified as a stellar host with an effective photospheric temperature of 5,388 K, a radius of 0.89 R☉, a mass of 0.908 M☉, an estimated bolometric luminosity of 0.599 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.1 Gyr and a metallicity of [Fe/H] = 0.12 dex (metal-rich relative to the Sun). From Earth, Kepler-322 shines at apparent V-band magnitude 13.687 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-322 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-322 c sharing its stellar neighborhood alongside Kepler-322 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-322 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,388 K |
| Stellar Radius | 0.8900 R☉ |
| Stellar Mass | 0.9080 M☉ |
| Bolometric Luminosity | 0.599 L☉ |
| Metallicity [Fe/H] | 0.120 dex |
| Stellar Age | 1.100 Gyr |
| Apparent Magnitude | V: 13.687 · G: 13.503 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.051000 AU |
| Orbital Period | 4.337 days |
| Mean Orbital Velocity | 127.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.7700° |
| Mean Bulk Density | 4.06 g/cm³ (16 km/s vesc) |
| Insolation Flux | 203.4060 S⊕ (~276,836 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1306.200 LY (400.480 pc) |