Kepler-1026 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1026 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1026, located approximately 1145.6 light-years (351.24 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.073% across the stellar disk), this world measures 2.21 Earth radii and has a measured mass of 5.52 Earth masses. Combining its mass and radius yields a mean bulk density of 2.82 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.13 g⊕ (11.08 m/s²), and an escape velocity of 17.7 km/s.
In its orbital architecture around Kepler-1026, Kepler-1026 b completes one full revolution every 36.516 Earth days at a semi-major axis of 0.1977 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 58.9 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.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 425 K (+152°C / +306°F) and receiving 5.99 S⊕ (~8,150 W/m²), Kepler-1026 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1026 is classified as a stellar host with an effective photospheric temperature of 4,948 K, a radius of 0.75 R☉, a mass of 0.79 M☉, an estimated bolometric luminosity of 0.303 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.57 Gyr and a metallicity of [Fe/H] = -0.02 dex (near-solar heavy-element abundance). From Earth, Kepler-1026 shines at apparent V-band magnitude 14.463 (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-1026 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,948 K |
| Stellar Radius | 0.7500 R☉ |
| Stellar Mass | 0.7900 M☉ |
| Bolometric Luminosity | 0.303 L☉ |
| Metallicity [Fe/H] | -0.020 dex |
| Stellar Age | 4.570 Gyr |
| Apparent Magnitude | V: 14.463 · G: 14.202 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.197700 AU |
| Orbital Period | 36.516 days |
| Mean Orbital Velocity | 58.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.1100° |
| Mean Bulk Density | 2.82 g/cm³ (17.7 km/s vesc) |
| Insolation Flux | 5.9880 S⊕ (~8,150 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1145.600 LY (351.239 pc) |