Kepler-286 d
Astrophysical Synthesis & Habitability Characterization
Kepler-286 d is a confirmed super-earth exoplanet orbiting the star Kepler-286, located approximately 4001.4 light-years (1226.85 parsecs) from the Solar System. First announced in 2014 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.02% across the stellar disk), this world measures 1.33 Earth radii and has a measured mass of 2.33 Earth masses. Combining its mass and radius yields a mean bulk density of 5.46 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.32 g⊕ (12.94 m/s²), and an escape velocity of 14.8 km/s.
In its orbital architecture around Kepler-286, Kepler-286 d completes one full revolution every 5.914 Earth days at a semi-major axis of 0.061 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 112.2 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 919 K (+646°C / +1195°F) and receiving 173.90 S⊕ (~236,678 W/m²), Kepler-286 d orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-286 is classified as a stellar host with an effective photospheric temperature of 5,580 K, a radius of 0.863 R☉, a mass of 0.83 M☉, an estimated bolometric luminosity of 0.648 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.75 Gyr and a metallicity of [Fe/H] = -0.25 dex (metal-poor relative to the Sun). From Earth, Kepler-286 shines at apparent V-band magnitude 15.863 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-286 system is a multi-planet architecture hosting 4 confirmed worlds, with Kepler-286 d sharing its stellar neighborhood alongside Kepler-286 b, Kepler-286 c, Kepler-286 e.
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-286 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,580 K |
| Stellar Radius | 0.8630 R☉ |
| Stellar Mass | 0.8300 M☉ |
| Bolometric Luminosity | 0.648 L☉ |
| Metallicity [Fe/H] | -0.250 dex |
| Stellar Age | 2.750 Gyr |
| Apparent Magnitude | V: 15.863 · G: 15.545 |
| System Architecture | 1 Star, 4 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.061000 AU |
| Orbital Period | 5.914 days |
| Mean Orbital Velocity | 112.2 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.8700° |
| Mean Bulk Density | 5.46 g/cm³ (14.8 km/s vesc) |
| Insolation Flux | 173.9000 S⊕ (~236,678 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 4001.400 LY (1226.850 pc) |