Kepler-1086 c
Astrophysical Synthesis & Habitability Characterization
Kepler-1086 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-1086, located approximately 1520.2 light-years (466.08 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1668% across the stellar disk), this world measures 2.94 Earth radii and has a measured mass of 8.96 Earth masses. Combining its mass and radius yields a mean bulk density of 1.94 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.04 g⊕ (10.2 m/s²), and an escape velocity of 19.5 km/s.
In its orbital architecture around Kepler-1086, Kepler-1086 c completes one full revolution every 161.516 Earth days at a semi-major axis of 0.503 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 33.9 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.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 2.940 R⊕, Kepler-1086 c exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star Kepler-1086 is classified as a stellar host with an effective photospheric temperature of 4,350 K, a radius of 0.66 R☉, a mass of 0.7 M☉, an estimated bolometric luminosity of 0.14 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.88 Gyr and a metallicity of [Fe/H] = 0.06 dex (metal-rich relative to the Sun). From Earth, Kepler-1086 shines at apparent V-band magnitude 16.002 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-1086 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-1086 c sharing its stellar neighborhood alongside Kepler-1086 b.
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-1086 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,350 K |
| Stellar Radius | 0.6600 R☉ |
| Stellar Mass | 0.7000 M☉ |
| Bolometric Luminosity | 0.14 L☉ |
| Metallicity [Fe/H] | 0.060 dex |
| Stellar Age | 2.880 Gyr |
| Apparent Magnitude | V: 16.002 · G: 15.555 |
| System Architecture | 2 Stars, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.503000 AU |
| Orbital Period | 161.516 days |
| Mean Orbital Velocity | 33.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 90.0000° |
| Mean Bulk Density | 1.94 g/cm³ (19.5 km/s vesc) |
| Insolation Flux | 0.5190 S⊕ (~706 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1520.200 LY (466.084 pc) |