Kepler-1687 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1687 b is a confirmed super-earth exoplanet orbiting the star Kepler-1687, located approximately 1360.1 light-years (417.01 parsecs) from the Solar System. First announced in 2020 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0437% across the stellar disk), this world measures 1.656 Earth radii and has a measured mass of 3.38 Earth masses. Combining its mass and radius yields a mean bulk density of 4.1 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-1687, Kepler-1687 b completes one full revolution every 5.78 Earth days at a semi-major axis of 0.0532 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 100.1 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 598 K (+325°C / +617°F) and receiving 30.22 S⊕ (~41,129 W/m²), Kepler-1687 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1687 is classified as a stellar host with an effective photospheric temperature of 4,132 K, a radius of 0.7261 R☉, a mass of 0.65 M☉, an estimated bolometric luminosity of 0.138 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.73 Gyr and a metallicity of [Fe/H] = -0.14 dex (metal-poor relative to the Sun). From Earth, Kepler-1687 shines at apparent V-band magnitude 15.928 (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-1687 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,132 K |
| Stellar Radius | 0.7261 R☉ |
| Stellar Mass | 0.6500 M☉ |
| Bolometric Luminosity | 0.138 L☉ |
| Metallicity [Fe/H] | -0.140 dex |
| Stellar Age | 3.730 Gyr |
| Apparent Magnitude | V: 15.928 · G: 15.473 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.053200 AU |
| Orbital Period | 5.78 days |
| Mean Orbital Velocity | 100.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 82.1300° |
| Mean Bulk Density | 4.1 g/cm³ (16 km/s vesc) |
| Insolation Flux | 30.2200 S⊕ (~41,129 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1360.100 LY (417.014 pc) |