Kepler-1977 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1977 b is a confirmed super-earth exoplanet orbiting the star Kepler-1977, located approximately 1933.2 light-years (592.71 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0489% across the stellar disk), this world measures 1.66 Earth radii and has a measured mass of 3.39 Earth masses. Combining its mass and radius yields a mean bulk density of 4.09 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-1977, Kepler-1977 b completes one full revolution every 4.537 Earth days at a semi-major axis of 0.0486 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 116.5 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 798 K (+525°C / +977°F) and receiving 95.61 S⊕ (~130,125 W/m²), Kepler-1977 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1977 is classified as a stellar host with an effective photospheric temperature of 4,805 K, a radius of 0.688 R☉, a mass of 0.769 M☉, an estimated bolometric luminosity of 0.226 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.3 Gyr and a metallicity of [Fe/H] = -0.06 dex (near-solar heavy-element abundance). From Earth, Kepler-1977 shines at apparent V-band magnitude 16.047 (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-1977 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,805 K |
| Stellar Radius | 0.6880 R☉ |
| Stellar Mass | 0.7690 M☉ |
| Bolometric Luminosity | 0.226 L☉ |
| Metallicity [Fe/H] | -0.060 dex |
| Stellar Age | 1.300 Gyr |
| Apparent Magnitude | V: 16.047 · G: 15.654 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.048600 AU |
| Orbital Period | 4.537 days |
| Mean Orbital Velocity | 116.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 87.1400° |
| Mean Bulk Density | 4.09 g/cm³ (16 km/s vesc) |
| Insolation Flux | 95.6100 S⊕ (~130,125 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1933.200 LY (592.711 pc) |