Kepler-329 c
Astrophysical Synthesis & Habitability Characterization
Kepler-329 c is a confirmed super-earth exoplanet orbiting the star Kepler-329, located approximately 1434.2 light-years (439.72 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1145% across the stellar disk), this world measures 1.93 Earth radii and has a measured mass of 4.38 Earth masses. Combining its mass and radius yields a mean bulk density of 3.36 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.18 g⊕ (11.57 m/s²), and an escape velocity of 16.9 km/s.
In its orbital architecture around Kepler-329, Kepler-329 c completes one full revolution every 18.685 Earth days at a semi-major axis of 0.113 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 65.8 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 402 K (+129°C / +264°F) and receiving 11.87 S⊕ (~16,154 W/m²), Kepler-329 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-329 is classified as a stellar host with an effective photospheric temperature of 4,257 K, a radius of 0.523 R☉, a mass of 0.602 M☉, an estimated bolometric luminosity of 0.081 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.47 Gyr and a metallicity of [Fe/H] = -0.44 dex (metal-poor relative to the Sun). From Earth, Kepler-329 shines at apparent V-band magnitude 15.886 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-329 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-329 c sharing its stellar neighborhood alongside Kepler-329 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-329 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,257 K |
| Stellar Radius | 0.5230 R☉ |
| Stellar Mass | 0.6020 M☉ |
| Bolometric Luminosity | 0.081 L☉ |
| Metallicity [Fe/H] | -0.440 dex |
| Stellar Age | 3.470 Gyr |
| Apparent Magnitude | V: 15.886 · G: 15.431 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.113000 AU |
| Orbital Period | 18.685 days |
| Mean Orbital Velocity | 65.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.3500° |
| Mean Bulk Density | 3.36 g/cm³ (16.9 km/s vesc) |
| Insolation Flux | 11.8690 S⊕ (~16,154 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1434.200 LY (439.719 pc) |