Kepler-377 b
Astrophysical Synthesis & Habitability Characterization
Kepler-377 b is a confirmed super-earth exoplanet orbiting the star Kepler-377, located approximately 2686.9 light-years (823.8 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0108% across the stellar disk), this world measures 1.39 Earth radii and has a measured mass of 2.51 Earth masses. Combining its mass and radius yields a mean bulk density of 5.15 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.3 g⊕ (12.75 m/s²), and an escape velocity of 15 km/s.
In its orbital architecture around Kepler-377, Kepler-377 b completes one full revolution every 12.51 Earth days at a semi-major axis of 0.109 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 94.8 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 875 K (+602°C / +1116°F) and receiving 139.11 S⊕ (~189,331 W/m²), Kepler-377 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-377 is classified as a stellar host with an effective photospheric temperature of 5,949 K, a radius of 1.224 R☉, a mass of 1.043 M☉, an estimated bolometric luminosity of 1.684 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.5 Gyr and a metallicity of [Fe/H] = 0.05 dex (near-solar heavy-element abundance). From Earth, Kepler-377 shines at apparent V-band magnitude 14.081 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-377 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-377 b sharing its stellar neighborhood alongside Kepler-377 c.
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-377 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,949 K |
| Stellar Radius | 1.2240 R☉ |
| Stellar Mass | 1.0430 M☉ |
| Bolometric Luminosity | 1.684 L☉ |
| Metallicity [Fe/H] | 0.050 dex |
| Stellar Age | 5.500 Gyr |
| Apparent Magnitude | V: 14.081 · G: 13.832 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.109000 AU |
| Orbital Period | 12.51 days |
| Mean Orbital Velocity | 94.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 88.3600° |
| Mean Bulk Density | 5.15 g/cm³ (15 km/s vesc) |
| Insolation Flux | 139.1120 S⊕ (~189,331 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2686.900 LY (823.804 pc) |