Kepler-1105 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1105 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1105, located approximately 1037.2 light-years (318 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0734% across the stellar disk), this world measures 2.01 Earth radii and has a measured mass of 4.7 Earth masses. Combining its mass and radius yields a mean bulk density of 3.19 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.16 g⊕ (11.38 m/s²), and an escape velocity of 17.1 km/s.
In its orbital architecture around Kepler-1105, Kepler-1105 b completes one full revolution every 4.422 Earth days at a semi-major axis of 0.0471 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 115.9 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 729 K (+456°C / +853°F) and receiving 47.18 S⊕ (~64,212 W/m²), Kepler-1105 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1105 is classified as a stellar host with an effective photospheric temperature of 4,299 K, a radius of 0.68 R☉, a mass of 0.71 M☉, an estimated bolometric luminosity of 0.142 L☉. Stellar evolution modeling indicates an estimated stellar age of 8.71 Gyr and a metallicity of [Fe/H] = 0.28 dex (metal-rich relative to the Sun). From Earth, Kepler-1105 shines at apparent V-band magnitude 15.315 (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-1105 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,299 K |
| Stellar Radius | 0.6800 R☉ |
| Stellar Mass | 0.7100 M☉ |
| Bolometric Luminosity | 0.142 L☉ |
| Metallicity [Fe/H] | 0.280 dex |
| Stellar Age | 8.710 Gyr |
| Apparent Magnitude | V: 15.315 · G: 15.142 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.047100 AU |
| Orbital Period | 4.422 days |
| Mean Orbital Velocity | 115.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 84.3400° |
| Mean Bulk Density | 3.19 g/cm³ (17.1 km/s vesc) |
| Insolation Flux | 47.1800 S⊕ (~64,212 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1037.200 LY (318.004 pc) |