K2-286 b
Astrophysical Synthesis & Habitability Characterization
K2-286 b is a confirmed sub-neptune exoplanet orbiting the star K2-286, located approximately 248.4 light-years (76.15 parsecs) from the Solar System. First announced in 2018 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0964% across the stellar disk), this world measures 2.1 Earth radii and has a measured mass of 5.06 Earth masses. Combining its mass and radius yields a mean bulk density of 3.01 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.15 g⊕ (11.28 m/s²), and an escape velocity of 17.4 km/s.
In its orbital architecture around K2-286, K2-286 b completes one full revolution every 27.359 Earth days at a semi-major axis of 0.1768 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 70.3 km/s (compared to Earth's 29.8 km/s).
ℹ️ Thermal & Atmospheric Regime: Current photometric and spectroscopic constraints for K2-286 b place it outside the conservative habitable zone definition pending further atmospheric characterization.
The host star K2-286 is classified as a low-mass red dwarf of spectral type M0 V with an effective photospheric temperature of 3,926 K, a radius of 0.62 R☉, a mass of 0.64 M☉, an estimated bolometric luminosity of 0.082 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, K2-286 shines at apparent V-band magnitude 12.881 (faint and requiring research-grade or CCD telescopic photometry) in the Southern 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: K2 · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | K2-286 |
| Spectral Type | M0 V |
| Effective Temp (Teff) | 3,926 K |
| Stellar Radius | 0.6200 R☉ |
| Stellar Mass | 0.6400 M☉ |
| Bolometric Luminosity | 0.082 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.881 · G: 12.165 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.176800 AU |
| Orbital Period | 27.359 days |
| Mean Orbital Velocity | 70.3 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.6700° |
| Mean Bulk Density | 3.01 g/cm³ (17.4 km/s vesc) |
| Insolation Flux | 2.8792 S⊕ (~3,919 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 248.400 LY (76.149 pc) |