Kepler-1328 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1328 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1328, located approximately 2653.4 light-years (813.54 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0082% across the stellar disk), this world measures 0.98 Earth radii and has a measured mass of 0.904 Earth masses. Combining its mass and radius yields a mean bulk density of 5.3 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 0.94 g⊕ (9.22 m/s²), and an escape velocity of 10.7 km/s.
In its orbital architecture around Kepler-1328, Kepler-1328 b completes one full revolution every 4.522 Earth days at a semi-major axis of 0.052 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 125.1 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 1214 K (+941°C / +1726°F) and receiving 545.67 S⊕ (~742,660 W/m²), Kepler-1328 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1328 is classified as a stellar host with an effective photospheric temperature of 5,780 K, a radius of 0.99 R☉, a mass of 1 M☉, an estimated bolometric luminosity of 0.981 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.57 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, Kepler-1328 shines at apparent V-band magnitude 13.969 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.
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-1328 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,780 K |
| Stellar Radius | 0.9900 R☉ |
| Stellar Mass | 1.0000 M☉ |
| Bolometric Luminosity | 0.981 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 4.570 Gyr |
| Apparent Magnitude | V: 13.969 · G: 13.803 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.052000 AU |
| Orbital Period | 4.522 days |
| Mean Orbital Velocity | 125.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 88.8200° |
| Mean Bulk Density | 5.3 g/cm³ (10.7 km/s vesc) |
| Insolation Flux | 545.6720 S⊕ (~742,660 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2653.400 LY (813.543 pc) |